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Sample records for beta receptor blockade

  1. Vasodilatory mechanisms of beta receptor blockade.

    OpenAIRE

    Rath, Géraldine; Balligand, Jean-Luc; Dessy, Chantal

    2012-01-01

    Beta-blockers are widely prescribed for the treatment of a variety of cardiovascular pathologies. Compared to traditional beta-adrenergic antagonists, beta-blockers of the new generation exhibit ancillary properties such as vasodilation through different mechanisms. This translates into a more favorable hemodynamic profile. The relative affinities of beta-adrenoreceptor antagonists towards the three beta-adrenoreceptor isotypes matter for predicting their functional impact on vasomotor contro...

  2. Antithrombotic effects of beta2-adrenergic receptor blockade on top of beta1-receptor blockade in patients with acute coronary syndrome or heart failure : a systematic review

    NARCIS (Netherlands)

    De Peuter, O.R.; Lussana, F.; Peters, R.J.; Büller, H.R.; Kamphuisen, P.W.

    2009-01-01

    Background: Non-selective beta1 + 2 blockers may have specific antithrombotic effects not present in eta1-blockers, due to a eta2-specific effect on sympathetic activity. Our aim was to assess the influence of eta2-receptor suppression on top of selective beta1-receptor blockade on the occurrence of

  3. Metabolic consequences of beta-adrenergic receptor blockade for the acutely ischemic dog myocardium

    Energy Technology Data Exchange (ETDEWEB)

    Westera, G.; Hollander, W. den; Wall, E.E. van der; Eenige, M.J. van; Scholtalbers, S.; Visser, F.C.; Roos, J.P.

    1984-02-01

    In an experimental study in 50 dogs the myocardial uptake of free fatty acids (FFAs) after beta-blockade was determined using radioiodinated heptadecanoic acid as a metabolic tracer. All 4 beta-blockers used (metoprolol, timolol, propranolol and pindolol) lowered the uptake of FFAs in the normal canine heart. Uptake of FFAs was also diminished after coronary artery occlusion per se, but administration of beta-blockers exerted little additional influence on the uptake of FFAs. This observation was qualitatively parallelled by the uptake of /sup 201/Tl in concomitant experiments. Plasma FFA levels were increased by pindolol (non-selective with intrinsic sympathomimetic activity), not changed by metoprolol (a cardioselective betablocking agent) and lowered by timolol and propranolol (both non-selective compounds). The extent of ischemic tissue, as reflected by uptake of iodoheptadecanoic acid and /sup 201/Tl, was diminished by metoprolol but not by other beta-blockers. Regional distribution of both tracers, as shown in the endo-epicardial uptake ratios, was hardly influenced by beta-blockade, except for a small increase of /sup 201/Tl uptake in non-occluded endocardium. Uptake of /sup 201/Tl as well as of iodoheptadecanoic acid in the ischemic area was increased by metoprolol, timolol and propranolol and decreased by pindolol. We conclude that beta-blocking agents confer different effects on myocardial uptake and metabolism of FFAs which might possibly be related to their different inherent properties.

  4. Normotensive sodium loading in conscious dogs: Regulation of renin secretion during beta receptor blockade

    DEFF Research Database (Denmark)

    Bie, Peter; Mølstrøm, Simon; Wamberg, Søren

    2009-01-01

    that in this setting, renin secretion and renin-dependent sodium excretion are controlled by via the renal nerves and therefore eliminated or reduced by blocking the action of norepinephrine on the juxtaglomerular cells with the beta1-receptor antagonist metoprolol. This was tested in conscious dogs by infusion of NaCl...... (20 micromol/kg/min for 180 min, NaLoad) during regular or low-sodium diet (0.03 mmol/kg/d, LowNa) with and without metoprolol (2 mg/kg plus 0.9 mg/kg/h). Vasopressin V2 receptors were blocked by Otsuka compound OPC31260 to facilitate clearance measurements. Body fluid volume was maintained by servo...

  5. Effect of beta blockade and beta stimulation on stage fright.

    Science.gov (United States)

    Brantigan, C O; Brantigan, T A; Joseph, N

    1982-01-01

    Stage fright, physiologically the "fight or flight" reaction, is a disabling condition to the professional musician. Because it is mediated by the sympathetic nervous system, we have investigated the effects of beta blockade on musical performance with propranolol in a double blind fashion and the effects of beta stimulation using terbutaline. Stage fright symptoms were evaluated in two trials, which included a total of 29 subjects, by questionnaire and by the State Trai Anxiety Inventory. Quality of musical performance was evaluated by experienced music critics. Beta blockade eliminates the physical impediments to performance caused by stage fright and even eliminates the dry mouth so frequently encountered. The quality of musical performance as judged by experienced music critics is significantly improved. This effect is achieved without tranquilization. Beta stimulating drugs increase stage fright problems, and should be used in performing musicians only after consideration of the detrimental effects which they may have on musical performance. PMID:6120650

  6. The second Lilly Prize Lecture, University of Newcastle, July 1977. beta-Adrenergic receptor blockade in hypertension, past, present and future.

    Science.gov (United States)

    Prichard, B N

    1978-01-01

    All beta-adrenoceptor blocking drugs that have been described share the common property of being competitive inhibitors. They differ in their associated properties, the presence or absence of cardioselectivity, membrane stabilizing activity, and partial agonist activity. Recently some beta-adrenoceptor blocking drugs have been reported which also possess alpha-adrenoceptor blocking activity. The associated properties have been used as a basis for classifying beta-adrenoceptor blocking drugs (Fitzgerald, 1969, 1972). The presence or absence of cardioselectivity is most useful for dividing beta-adrenoceptor blocking drugs. The non-selective drugs (Division I) can be further divided according to the presence or absence of intrinsic sympathomimetic activity (ISA) and membrane stabilizing activity (Fitzgerald's groups I-IV). Group I possess both membrane activity and ISA, e.g. alprenolol, oxprenolol, group II just membrane action, e.g. propanolol, group III ISA but no membrane action, e.g. pindolol. Fitzgerald placed pindolol in group I but should be placed in group III as it possesses a high degree of beta-adrenoceptor blocking potency in relation to its membrane activity (Prichard, 1974). Finally drugs in group IV have neither ISA nor membrane action, e.g. sotalol, timolol. The cardioselective drugs (Division II) can be similarly sub-divided into groups I-IV according to the presence or absence of ISA or membrane action (Fitzgerald grouped all these together as group V). Lastly there are new beta-adrenergic receptor blocking drugs which in addition have alpha- adrenergic receptor blocking properties (Division III). PMID:26370

  7. The second Lilly Prize Lecture, University of Newcastle, July 1977. beta-Adrenergic receptor blockade in hypertension, past, present and future.

    Science.gov (United States)

    Prichard, B N

    1978-05-01

    All beta-adrenoceptor blocking drugs that have been described share the common property of being competitive inhibitors. They differ in their associated properties, the presence or absence of cardioselectivity, membrane stabilizing activity, and partial agonist activity. Recently some beta-adrenoceptor blocking drugs have been reported which also possess alpha-adrenoceptor blocking activity. The associated properties have been used as a basis for classifying beta-adrenoceptor blocking drugs (Fitzgerald, 1969, 1972). The presence or absence of cardioselectivity is most useful for dividing beta-adrenoceptor blocking drugs. The non-selective drugs (Division I) can be further divided according to the presence or absence of intrinsic sympathomimetic activity (ISA) and membrane stabilizing activity (Fitzgerald's groups I-IV). Group I possess both membrane activity and ISA, e.g. alprenolol, oxprenolol, group II just membrane action, e.g. propanolol, group III ISA but no membrane action, e.g. pindolol. Fitzgerald placed pindolol in group I but should be placed in group III as it possesses a high degree of beta-adrenoceptor blocking potency in relation to its membrane activity (Prichard, 1974). Finally drugs in group IV have neither ISA nor membrane action, e.g. sotalol, timolol. The cardioselective drugs (Division II) can be similarly sub-divided into groups I-IV according to the presence or absence of ISA or membrane action (Fitzgerald grouped all these together as group V). Lastly there are new beta-adrenergic receptor blocking drugs which in addition have alpha- adrenergic receptor blocking properties (Division III).

  8. Benefits and harms of perioperative beta-blockade

    DEFF Research Database (Denmark)

    Wetterslev, Jørn; Juul, Anne Benedicte

    2006-01-01

    randomized trials. However, confidence intervals of the intervention effects in the meta-analyses are wide, leaving room for both benefits and harms. The largest observational study performed suggests that perioperative beta-blockade is associated with higher mortality in patients with low cardiac risk...

  9. H2-receptor blockade and exercise-induced asthma.

    OpenAIRE

    Nogrady, S G; Hahn, A G

    1984-01-01

    While in vitro studies suggest that H2-receptor blockade enhances mediator release from bronchial mast cells and leads to bronchoconstriction, in vivo studies have given conflicting results. Eight asthmatic subjects were given cimetidine 800 mg and placebo double-blind on different days. Baseline values of forced expiratory volume in one second (FEV1) were obtained before an 8 min standardized exercise test using a bicycle ergometer. Subjects inhaled cold, dry air and exercise on cimetidine a...

  10. Presynaptic snake beta-neurotoxins produce tetanic fade and endplate potential run-down during neuromuscular blockade in mouse diaphragm.

    Science.gov (United States)

    Wilson, H I; Nicholson, G M

    1997-11-01

    The present study investigated the ability of a number of presynaptic snake neurotoxins (snake beta-neurotoxins) to produce nerve-evoked train-of-four fade, tetanic fade and endplate potential run-down during the development of neuromuscular blockade in the isolated mouse phrenic-hemidiaphragm nerve-muscle preparation. All the snake beta-neurotoxins tested, with the exception of notexin, produced train-of-four and tetanic fade of nerve-evoked isometric muscle contractions. Train-of-four fade was not present during the initial depressant or facilitatory phases of muscle tension produced by the snake beta-neurotoxins but developed progressively during the final depressant phase that precedes complete neuromuscular blockade. The 'non-neurotoxic' bovine pancreatic phospholipase A2 and the 'low-toxicity' phospholipase A2 from Naja naja atra venom failed to elicit train-of-four fade, indicating that the phospholipase activity of the snake beta-neurotoxins is not responsible for the development of fade. Intracellular recording of endplate potentials (EPPs) elicited by nerve-evoked trains of stimuli showed a progressive run-down in EPP amplitude during the train following incubation with all snake beta-neurotoxins except notexin. Again this run-down in EPP amplitude was confined to the final depressant phase of snake beta-neurotoxin action. However when EPP amplitude fell to near uniquantal levels (fade was reduced. Unlike postjunctional snake alpha-neurotoxins, prejunctional snake beta-neurotoxins interfere with acetylcholine release at the neuromuscular junction during the development of neuromuscular blockade. This study provides further support for the hypothesis that fade in twitch and tetanic muscle tension is due to an underlying rundown in EPP amplitude resulting from a prejunctional alteration of transmitter release rather than a use-dependent block of postjunctional nicotinic receptors.

  11. Foetal vascular responses to thromboxane receptor blockade

    Directory of Open Access Journals (Sweden)

    B. A. Meyer

    1992-01-01

    Full Text Available We hypothesized that foetal administration of SQ-29,548, a putative thromboxane receptor blocker, would prevent foeto–placental vasoconstriction produced by the thromboxane mimic U46619. Arterial blood gases, continuous monitoring of maternal and foetal heart rates and blood pressures were performed in chronically catheterized pregnant ewes. Foetal blood flows and vascular resistance were determined with radioactive microspheres. SQ-29,548 effectively blocked the expected vasoconstrictive effects of thromboxane. However, prolonged infusion of SQ-29,548 resulted in significant decreases in umbilical–placental blood flow and foetal mean arterial pressure. This was accompanied by a respiratory acidemia. Potential therapy for the vasoconstrictive disorders of pregnancy with SQ-29,548 awaits further investigation of its intrinsic vasoactive properties in the umbilical–placental vasculature.

  12. Effects of beta-adrenergic blockade on ventilation and gas exchange during incremental exercise.

    Science.gov (United States)

    Dodd, S; Powers, S; O'Malley, N; Brooks, E; Sommers, H

    1988-08-01

    Controversy exists concerning the effects of acute beta-adrenergic blockade on ventilation during exercise. Hence, the purpose of this study was to determine the effects of acute beta blockade on ventilation and gas exchange during incremental exercise. Nine male subjects underwent incremental exercise on a cycle ergometer (30 W.min-1) to exhaustion, with one trial being performed 60 min after the subject ingested propranolol hydrochloride (Inderal 1 mg.kg-1 BW) while the second test served as control. The treatment order was counterbalanced to preclude any ordering effect on the results, and 1 week separated the tests. Ventilation and gas exchange were monitored by open circuit techniques. No difference (p greater than 0.05) existed in VE, % Hb sat, VCO2, ventilatory threshold, and VE/VCO2 between treatments at the same exercise stage. VO2max was lowered from 3.82 to 3.26 l.min-1 (p less than 0.05) and HRmax was reduced from 190 to 150 bpm (p less than 0.05) as a result of beta blockade. These data suggested that acute beta blockade had no effect on exercise ventilation, but decreased HRmax at comparable work rates. In addition, VO2max and exercise time to exhaustion were hindered, probably due to beta blockade limitation of HRmax, and, thus, oxygen transport. PMID:3178619

  13. Cardiovascular response to beta-adrenergic blockade or activation in 23 inbred mouse strains.

    Directory of Open Access Journals (Sweden)

    Corinne Berthonneche

    Full Text Available We report the characterisation of 27 cardiovascular-related traits in 23 inbred mouse strains. Mice were phenotyped either in response to chronic administration of a single dose of the beta-adrenergic receptor blocker atenolol or under a low and a high dose of the beta-agonist isoproterenol and compared to baseline condition. The robustness of our data is supported by high trait heritabilities (typically H(2>0.7 and significant correlations of trait values measured in baseline condition with independent multistrain datasets of the Mouse Phenome Database. We then focused on the drug-, dose-, and strain-specific responses to beta-stimulation and beta-blockade of a selection of traits including heart rate, systolic blood pressure, cardiac weight indices, ECG parameters and body weight. Because of the wealth of data accumulated, we applied integrative analyses such as comprehensive bi-clustering to investigate the structure of the response across the different phenotypes, strains and experimental conditions. Information extracted from these analyses is discussed in terms of novelty and biological implications. For example, we observe that traits related to ventricular weight in most strains respond only to the high dose of isoproterenol, while heart rate and atrial weight are already affected by the low dose. Finally, we observe little concordance between strain similarity based on the phenotypes and genotypic relatedness computed from genomic SNP profiles. This indicates that cardiovascular phenotypes are unlikely to segregate according to global phylogeny, but rather be governed by smaller, local differences in the genetic architecture of the various strains.

  14. Renal and cardiac function during alpha1-beta-blockade in congestive heart failure

    DEFF Research Database (Denmark)

    Heitmann, M; Davidsen, U; Stokholm, K H;

    2002-01-01

    The kidney and the neurohormonal systems are essential in the pathogenesis of congestive heart failure (CHF) and the physiologic response. Routine treatment of moderate to severe CHF consists of diuretics, angiotensin-converting enzyme (ACE) inhibition and beta-blockade. The need for control...... of renal function during initiation of ACE-inhibition in patients with CHF is well known. The aim of this study was to investigate whether supplementation by a combined alpha1-beta-blockade to diuretics and ACE-inhibition might improve cardiac function without reducing renal function....

  15. Targeting of beta adrenergic receptors results in therapeutic efficacy against models of hemangioendothelioma and angiosarcoma.

    Directory of Open Access Journals (Sweden)

    Jessica M Stiles

    Full Text Available Therapeutic targeting of the beta-adrenergic receptors has recently shown remarkable efficacy in the treatment of benign vascular tumors such as infantile hemangiomas. As infantile hemangiomas are reported to express high levels of beta adrenergic receptors, we examined the expression of these receptors on more aggressive vascular tumors such as hemangioendotheliomas and angiosarcomas, revealing beta 1, 2, and 3 receptors were indeed present and therefore aggressive vascular tumors may similarly show increased susceptibility to the inhibitory effects of beta blockade. Using a panel of hemangioendothelioma and angiosarcoma cell lines, we demonstrate that beta adrenergic inhibition blocks cell proliferation and induces apoptosis in a dose dependent manner. Beta blockade is selective for vascular tumor cells over normal endothelial cells and synergistically effective when combined with standard chemotherapeutic or cytotoxic agents. We demonstrate that inhibition of beta adrenergic signaling induces large scale changes in the global gene expression patterns of vascular tumors, including alterations in the expression of established cell cycle and apoptotic regulators. Using in vivo tumor models we demonstrate that beta blockade shows remarkable efficacy as a single agent in reducing the growth of angiosarcoma tumors. In summary, these experiments demonstrate the selective cytotoxicity and tumor suppressive ability of beta adrenergic inhibition on malignant vascular tumors and have laid the groundwork for a promising treatment of angiosarcomas in humans.

  16. Assessment of Methods for the Intracellular Blockade of GABAA Receptors.

    Science.gov (United States)

    Atherton, Laura A; Burnell, Erica S; Mellor, Jack R

    2016-01-01

    Selective blockade of inhibitory synaptic transmission onto specific neurons is a useful tool for dissecting the excitatory and inhibitory synaptic components of ongoing network activity. To achieve this, intracellular recording with a patch solution capable of blocking GABAA receptors has advantages over other manipulations, such as pharmacological application of GABAergic antagonists or optogenetic inhibition of populations of interneurones, in that the majority of inhibitory transmission is unaffected and hence the remaining network activity preserved. Here, we assess three previously described methods to block inhibition: intracellular application of the molecules picrotoxin, 4,4'-dinitro-stilbene-2,2'-disulphonic acid (DNDS) and 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS). DNDS and picrotoxin were both found to be ineffective at blocking evoked, monosynaptic inhibitory postsynaptic currents (IPSCs) onto mouse CA1 pyramidal cells. An intracellular solution containing DIDS and caesium fluoride, but lacking nucleotides ATP and GTP, was effective at decreasing the amplitude of IPSCs. However, this effect was found to be independent of DIDS, and the absence of intracellular nucleotides, and was instead due to the presence of fluoride ions in this intracellular solution, which also blocked spontaneously occurring IPSCs during hippocampal sharp waves. Critically, intracellular fluoride ions also caused a decrease in both spontaneous and evoked excitatory synaptic currents and precluded the inclusion of nucleotides in the intracellular solution. Therefore, of the methods tested, only fluoride ions were effective for intracellular blockade of IPSCs but this approach has additional cellular effects reducing its selectivity and utility. PMID:27501143

  17. Effect of 5-HT7 receptor blockade on liver regeneration after 60-70% partial hepatectomy

    OpenAIRE

    Tzirogiannis, Konstantinos N; Kourentzi, Kalliopi T; Zyga, Sofia; Papalimneou, Vassiliki; Tsironi, Maria; Grypioti, Agni D; Protopsaltis, Ioannis; Panidis, Dimitrios; Panoutsopoulos, Georgios I

    2014-01-01

    Background Serotonin exhibits a vast repertoire of actions including cell proliferation and differentiation. The effect of serotonin, as an incomplete mitogen, on liver regeneration has recently been unveiled and is mediated through 5-HT2 receptor. The aim of the present study was to investigate the effect of 5-HT7 receptor blockade on liver regeneration after partial hepatectomy. Methods Male Wistar rats were subjected to 60-70% partial hepatectomy. 5-HT7 receptor blockade was applied by int...

  18. Effect of serotonin receptor blockade on endocrine and cardiovascular responses to head-up tilt in humans

    DEFF Research Database (Denmark)

    Matzen, S; Secher, N H; Knigge, U;

    1993-01-01

    Effects of blockade of serotonin (5-HT) receptors on the integrated cardiovascular and endocrine adaptations during head-up tilt were investigated in normal men. In control experiments 50 degrees head-up tilt increased heart rate (HR), total peripheral resistance (TPR), plasma renin activity (PRA......) and sympathetic activity (plasma noradrenaline; NA). A moderate increase in pituitary-adrenal hormones (plasma ACTH, beta-END and cortisol) was observed. After a mean tilt time of 30 +/- 5 min (n = 20) presyncopal symptoms associated with decreases in HR, TPR and arterial pressure occurred. At this time pituitary...

  19. Effect of alpha and beta adrenergic blockade on epinephrine induced pulmonary insufficiency.

    Science.gov (United States)

    Berk, J L; Hagen, J F; Koo, R

    1976-04-01

    Recent studies demonstrated that epinephrine causes significant pulmonary A-V shunting. This study reports the effect of alpha and beta adrenergic blockade on this shunting. Sixty-three anesthetized mongrel dogs were ventilated with a mechanical respirator. Measurements of (1) the pulmonary shunt, (2) cardiac output, (3) mean pulmonary artery, pulmonary capillary wedge and systemic pressures, and (4) pulmonary and systemic vascular resistances were obtained at 5, 15 and 30 minute intervals during the first hour and hourly for 5 hours. Fifteen dogs received no treatment. All others received epinephrine hydrochloride, 2 mug/kg/min for 5 hours. Ten received epinephrine only. Ten were pretreated with propranolol hydrochloride, 250 mug/kg, 12 with phenoxybenzamine, 1 mg/kg, and 16 with phenoxybenzamine and propranolol. Propranolol significantly decreased the epinephrine induced pulmonary shunt at all times and was the most effective drug. Phenoxybenzamine decreased the early shunting, but less than propranolol, and did not decrease the late shunting. Blockade with propranolol and phenoxybenzamine was less effective than propranolol alone. Based on the observed hemodynamic changes it was suggested that beta blockade is effective in reducing epinephrine induced pulmonary insufficiency by favorably altering the flow and distribution of pulmonary blood flow which in turn decreases epinephrine induced ventilation-perfusion inequalities and capillary hypertension both of which result in shunting. Conversely phenoxybenzamine has an unfavorable effect on the pulmonary flow. These studies support previous work in animals and man which showed that beta adrenergic stimulation is important in the pathogenesis of pulmonary insufficiency. Because the amounts of epinephrine used produce blood levels observed in critical illness, these studies add support to a relationship between the increased catecholamine stimulation of critical illness and the associated and often unexplained

  20. Orexin-1 receptor blockade dysregulates REM sleep in the presence of orexin-2 receptor antagonism

    OpenAIRE

    Christine eDugovic; Shelton, Jonathan E.; Sujin eYun; Pascal eBonaventure; Shireman, Brock T.; Lovenberg, Timothy W.

    2014-01-01

    In accordance with the prominent role of orexins in the maintenance of wakefulness via activation of orexin-1 (OX1R) and orexin-2 (OX2R) receptors, various dual OX1/2R antagonists have been shown to promote sleep in animals and humans. While selective blockade of OX2R seems to be sufficient to initiate and prolong sleep, the beneficial effect of additional inhibition of OX1R remains controversial. The relative contribution of OX1R and OX2R to the sleep effects induced by a dual OX1/2R antagon...

  1. Functional capacity in healthy volunteers before and following beta-blockade with controlled-release metoprolol.

    Science.gov (United States)

    Rønnevik, P K; Nordrehaug, J E; von der Lippe, G

    1995-01-01

    The effects of the beta 1-selective beta-adrenergic blocker metoprolol on physiological responses, exercise capacity and gas exchange parameters were measured in healthy men using different graded bicycle exercise protocols on separate days before and following administration of 200 mg controlled-release metoprolol. Eleven men performed in randomised order maximal cardiopulmonary exercise testing on 50-W/6-min stage, 50-W/3-min stage and ramp (15-W/min-1) protocols. Peak heart rate and peak heart rate-blood pressure products were similar on all exercise protocols, and were significantly reduced by metoprolol. Submaximal and peak oxygen consumption were similar before and following beta-adrenoceptor blockade. Depending on the exercise protocol applied, an insignificant decrease of 4-10% in maximal cumulated exercise capacity (work-rate x time integral) was observed following administration of metoprolol. It is concluded that in healthy men evaluated with different exercise protocols the beta 1-selective controlled-release beta-adrenoceptor blocker metoprolol does not influence exercise capacity despite a marked reduction of heart rate and rate-pressure product. PMID:7589026

  2. Blockade of lysophosphatidic acid receptors LPAR1/3 ameliorates lung fibrosis induced by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gan, Lu [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Xue, Jian-Xin [Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Laboratory of Stem Cell Biology, West China Hospital, Sichuan University, Chengdu (China); Li, Xin [Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Liu, De-Song [Department of Pediatrics, Sichuan Provincial Hospital of Women and Children, Chengdu (China); Ge, Yan; Ni, Pei-Yan; Deng, Lin [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Lu, You, E-mail: radyoulu@hotmail.com [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Department of Thoracic Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu (China); Jiang, Wei, E-mail: wcumsjw72@hotmail.com [State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu (China); Molecular Medicine Research Center, West China Hospital, Sichuan University, Chengdu (China)

    2011-05-27

    Highlights: {yields} Lysophosphatidic acid (LPA) levels and its receptors LPAR1/3 transcripts were elevated during the development of radiation-induced lung fibrosis. {yields} Lung fibrosis was obviously alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. {yields} VPC12249 administration effectively inhibited radiation-induced fibroblast accumulation in vivo, and suppressed LPA-induced fibroblast proliferation in vitro. {yields} LPA-LPAR1/3 signaling regulated TGF{beta}1 and CTGF expressions in radiation-challenged lungs, but only influenced CTGF expression in cultured fibroblasts. {yields} LPA-LPAR1/3 signaling induced fibroblast proliferation through a CTGF-dependent pathway, rather than through TGF{beta}1 activation. -- Abstract: Lung fibrosis is a common and serious complication of radiation therapy for lung cancer, for which there are no efficient treatments. Emerging evidence indicates that lysophosphatidic acid (LPA) and its receptors (LPARs) are involved in the pathogenesis of fibrosis. Here, we reported that thoracic radiation with 16 Gy in mice induced development of radiation lung fibrosis (RLF) accompanied by obvious increases in LPA release and LPAR1 and LPAR3 (LPAR1/3) transcripts. RLF was significantly alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. VPC12249 administration effectively prolonged animal survival, restored lung structure, inhibited fibroblast accumulation and reduced collagen deposition. Moreover, profibrotic cytokines in radiation-challenged lungs obviously decreased following administration of VPC12249, including transforming growth factor {beta}1 (TGF{beta}1) and connective tissue growth factor (CTGF). In vitro, LPA induced both fibroblast proliferation and CTGF expression in a dose-dependent manner, and both were suppressed by blockade of LPAR1/3. The pro-proliferative activity of LPA on fibroblasts was inhibited by siRNA directed against CTGF. Together, our data suggest that the LPA-LPAR1

  3. Maintained cerebral metabolic ratio during exercise in patients with beta-adrenergic blockade

    DEFF Research Database (Denmark)

    Gam, Christiane M B; Rasmussen, Peter; Secher, Niels H;

    2009-01-01

    BACKGROUND: Decreased cerebral metabolic ratio (CMR) [molar uptake of O(2) versus molar uptake of (glucose + (1/2) lactate)] during exercise is attenuated by intravenous administration of the non-selective beta-adrenergic receptor antagonist propranolol. We evaluated to what extent cirrhotic pati......-selective beta-adrenergic receptor antagonist attenuates cerebral non-oxidative metabolism Udgivelsesdato: 2009/11......BACKGROUND: Decreased cerebral metabolic ratio (CMR) [molar uptake of O(2) versus molar uptake of (glucose + (1/2) lactate)] during exercise is attenuated by intravenous administration of the non-selective beta-adrenergic receptor antagonist propranolol. We evaluated to what extent cirrhotic...... patients in oral treatment with propranolol are able to mobilize brain non-oxidative carbohydrate metabolism. METHODS: Incremental cycle ergometry to exhaustion (86 +/- 4.2 W; mean +/- SD) was performed in eight cirrhotic patients instrumented with a catheter in the brachial artery and one retrograde...

  4. Blockade of beta-adrenoceptors enhances cAMP signal transduction in vivo

    Science.gov (United States)

    Whalen, E. J.; Johnson, A. K.; Lewis, S. J.

    1998-01-01

    The aim of this study was to determine whether the blockade of beta-adrenoceptors would enhance cAMP-mediated signal transduction processes in vivo. The administration of the membrane permeable cAMP analogue, 8-(4-chlorophenylthiol)-cAMP (8-CPT-cAMP, 10 micromol/kg, i.v.) produced an increase in heart rate (+27 +/- 2%, P < 0.05), a fall in mean arterial blood pressure (-21 +/- 3%, P < 0.05) and falls in hindquarter (-12 +/- 3%, P < 0.05) and mesenteric (-32 +/- 3%, P < 0.05) vascular resistances in pentobarbital-anesthetized rats. The beta-adrenoceptor antagonist, propranolol (1 mg/kg, i.v.) lowered heart rate (-12 +/- 3%, P < 0.05) but did not affect mean arterial blood pressure or vascular resistances. The tachycardia, hypotension and vasodilation produced by 8-CPT-cAMP were exaggerated after administration of propranolol (P < 0.05 for all comparisons). The nitric oxide-donor, sodium nitroprusside (2 microg/kg, i.v.), produced falls in mean arterial blood pressure and vascular resistances of similar magnitude to those produced by 8-CPT-cAMP. These sodium nitroprusside-induced responses were unaffected by propranolol (P < 0.05 for all comparisons). Sodium nitroprusside also produced a minor increase in heart rate (+5 +/- 1%, P < 0.05) which was abolished by propranolol. These findings suggest that 8-CPT-cAMP directly increases heart rate and that blockade of beta-adrenoceptors enhances the potency of cAMP within the heart and vasculature.

  5. Human adipose tissue blood flow during prolonged exercise, III. Effect of beta-adrenergic blockade, nicotinic acid and glucose infusion

    DEFF Research Database (Denmark)

    Bülow, J

    1981-01-01

    acid, during acute i.v. beta-adrenergic blockade by propranolol, and during continuous i.v. infusion of glucose. The most pronounced lipid mobilization and utilization during work was seen in the control experiments where ATBF rose 3-fold on average from the initial rest period to the third hour...

  6. Value of the addition of Amlodipine to atenolol in patients with angina pectoris despite adequate beta blockade

    NARCIS (Netherlands)

    Dunselman, PHJM; Bouwens, LHM; Herweijer, AH; Bernink, PJLM

    1998-01-01

    Anginal patients who remain symptomatic despite optimally dosed beta blockade may also be given dihydropyridine calcium antagonists. This treatment regimen was examined in a double-blind parallel, randomized, controlled study in 147 patients with angina and positive bicycle exercise tests despite op

  7. Comparative study of the effects of stimulation or blockade of beta-adrenoceptors on the head-twitches induced in mice by 5-hydroxytryptophan versus 5-methoxy-N, N-dimethyltryptamine.

    Science.gov (United States)

    Martin, P; Soubrié, P; Simon, P

    1986-01-01

    This study aimed at comparing the effects of blockade or stimulation of beta-adrenoceptors on the head-twitch response induced in mice by direct (5-MeODMT) or indirect (5-HTP) activation of serotonergic receptors shows that: beta-agonists (clenbuterol and salbutamol) increased the 5-HTP-induced head-twitches and decreased the response to 5-MeODMT. beta-agonists (propranolol and penbutolol) reduced the head-twitches elicited by 5-HTP but enhanced those induced by 5-MeODMT. Under our experimental conditions, desipramine behaved like the beta-agonists studied. Prior intracerebroventricular injection of 5,7-DHT enhanced the response to 5-MeODMT but did not prevent the antagonism of clenbuterol against 5-MeODMT-induced head-twitches. These findings suggest that beta-receptors are in a position to regulate differentially serotonin transmission. PMID:2875219

  8. Use of beta adrenoceptor blockade during and after acute myocardial infarction.

    Science.gov (United States)

    Sleight, P

    1986-01-01

    In the last year, two large randomized controlled trials of metoprolol (MIAMI, almost 6,000 patients) and atenolol (ISIS 1, over 16,000 patients) given intravenously within 12 hours of the onset of acute myocardial infarction reduced mortality by about 15% in low-risk subjects. The reduction was significant for atenolol (2P = 0.04) but not for metoprolol, probably because of the smaller size of that trial. The reduction in mortality in both trials was nearly all in the first 36 hours, a finding that reduced the fears that the treatment might produce irreversible failure, shock, or heart block. Tolerance in these relatively low-risk subjects (control mortality about 5%) was good. Inotropes were used in 1-2% more subjects in the beta-blocked group but were effective in reversing the side effects without increasing mortality. No clear subgroups (age, sex, site, time from onset, initial blood pressure or heart rate) were found in which treatment was more beneficial. In the ISIS study, patients with higher heart rates were more likely to need inotropes after beta blockade and patients with long PR intervals at entry were more likely to develop block. Neither of these complications resulted in excess mortality in the blocked group, which suggests that these adverse effects were largely reversible. PMID:2871805

  9. Investigation of Prolactin Receptor Activation and Blockade Using Time-Resolved Fluorescence Resonance Energy Transfer

    Directory of Open Access Journals (Sweden)

    Estelle eTallet

    2011-09-01

    Full Text Available The prolactin receptor (PRLR is emerging as a therapeutic target in oncology. Knowledge-based drug design led to the development of a pure PRLR antagonist (Del1-9-G129R-hPRL that was recently shown to prevent PRL-induced mouse prostate tumorogenesis. In humans, the first gain-of-function mutation of the PRLR (PRLRI146L was recently identified in breast tumor patients. At the molecular level, the actual mechanism of action of these two novel players in the PRL system remains elusive. In this study, we addressed whether constitutive PRLR activation (PRLRI146L or PRLR blockade (antagonist involved alteration of receptor oligomerization and/or of inter-chain distances compared to unstimulated and PRL-stimulated PRLR. Using a combination of various biochemical and spectroscopic approaches (co-IP, blue-native electrophoresis, BRET1, we demonstrated that preformed PRLR homodimers are altered neither by PRL- or I146L-induced receptor triggering, nor by antagonist-mediated blockade. These findings were confirmed using a novel time-resolved fluorescence resonance energy transfer (TR-FRET technology that allows monitoring distance changes between cell-surface tagged receptors. This technology revealed that PRLR blockade or activation did not involve detectable distance changes between extracellular domains of receptor chains within the dimer. This study merges with our previous structural investigations suggesting that the mechanism of PRLR activation solely involves intermolecular contact adaptations leading to subtle intramolecular rearrangements.

  10. Orexin-1 receptor blockade dysregulates REM sleep in the presence of orexin-2 receptor antagonism

    Directory of Open Access Journals (Sweden)

    Christine eDugovic

    2014-02-01

    Full Text Available In accordance with the prominent role of orexins in the maintenance of wakefulness via activation of orexin-1 (OX1R and orexin-2 (OX2R receptors, various dual OX1/2R antagonists have been shown to promote sleep in animals and humans. While selective blockade of OX2R seems to be sufficient to initiate and prolong sleep, the beneficial effect of additional inhibition of OX1R remains controversial. The relative contribution of OX1R and OX2R to the sleep effects induced by a dual OX1/2R antagonist was further investigated in the rat, and specifically on rapid eye movement (REM sleep since a deficiency of the orexin system is associated with narcolepsy/cataplexy based on clinical and pre-clinical data. As expected, the dual OX1/2R antagonist SB-649868 was effective in promoting non-REM (NREM and REM sleep following oral dosing (10 and 30 mg/kg at the onset of the dark phase. However, a disruption of REM sleep was evidenced by a more pronounced reduction in the onset of REM as compared to NREM sleep, a marked enhancement of the REM/total sleep ratio, and the occurrence of a few episodes of direct wake to REM sleep transitions (REM intrusion. When administered subcutaneously, the OX2R antagonist JNJ-10397049 (10 mg/kg increased NREM duration whereas the OX1R antagonist GSK-1059865 (10 mg/kg did not alter sleep. REM sleep was not affected either by OX2R or OX1R blockade alone, but administration of the OX1R antagonist in combination with the OX2R antagonist induced a significant reduction in REM sleep latency and an increase in REM sleep duration at the expense of the time spent in NREM sleep. These results indicate that additional blockade of OX1R to OX2R antagonism elicits a dysregulation of REM sleep by shifting the balance in favor of REM sleep at the expense of NREM sleep that may increase the risk of adverse events. Translation of this hypothesis remains to be tested in the clinic.

  11. Dopamine D2-receptor blockade enhances decoding of prefrontal signals in humans.

    Science.gov (United States)

    Kahnt, Thorsten; Weber, Susanna C; Haker, Helene; Robbins, Trevor W; Tobler, Philippe N

    2015-03-01

    The prefrontal cortex houses representations critical for ongoing and future behavior expressed in the form of patterns of neural activity. Dopamine has long been suggested to play a key role in the integrity of such representations, with D2-receptor activation rendering them flexible but weak. However, it is currently unknown whether and how D2-receptor activation affects prefrontal representations in humans. In the current study, we use dopamine receptor-specific pharmacology and multivoxel pattern-based functional magnetic resonance imaging to test the hypothesis that blocking D2-receptor activation enhances prefrontal representations. Human subjects performed a simple reward prediction task after double-blind and placebo controlled administration of the D2-receptor antagonist amisulpride. Using a whole-brain searchlight decoding approach we show that D2-receptor blockade enhances decoding of reward signals in the medial orbitofrontal cortex. Examination of activity patterns suggests that amisulpride increases the separation of activity patterns related to reward versus no reward. Moreover, consistent with the cortical distribution of D2 receptors, post hoc analyses showed enhanced decoding of motor signals in motor cortex, but not of visual signals in visual cortex. These results suggest that D2-receptor blockade enhances content-specific representations in frontal cortex, presumably by a dopamine-mediated increase in pattern separation. These findings are in line with a dual-state model of prefrontal dopamine, and provide new insights into the potential mechanism of action of dopaminergic drugs. PMID:25740537

  12. Identification and specific blockade of two receptors for histamine in the cardiovascular system.

    Science.gov (United States)

    Powell, J R; Brody, M J

    1976-01-01

    Histamine caused a fall in blood pressure in anesthetized dogs and cats which was only partially attenuated by mepyramine (pyrilamine), a histamine type H1-receptor antagonist. Further treatment with burimide or metiamide, type H2-receptor antagonists, caused nearly complete attenuation of the response to histamine. Burimamide alone had no effect on vasodilatation produced by histamine in the dog gracilis muscle whereas mepyramine alone caused a partial attenuation. An H2-receptor agonist, 4-methylhistamine and an H1-receptor agonist, 2-(2-pyridyl)ethylamine, both produced vasodilatation which was blocked by metiamide and mepyramine, respectively. Constriction of the saphenous vein produced by histamine was found to involve interaction with H1-receptors only. In the intact dog, histamine increased heart rate and decreased left ventricular dp/dt through direct effects. Mepyramine prevented the increase in heart rate but did not affect the chronotropic actions of isoproterenol and glyceryl trinitrate. H1-receptor blockade did not alter inotropic effects whereas subsequent H2-receptor blockade prevented the negative inotropic effect of histamine. It is concluded that both peripheral vascular and cardiac responses to histamine are mediated through activation of H1- and H2-histamine receptors.

  13. The Effect of Opioid Receptor Blockade on the Neural Processing of Thermal Stimuli

    OpenAIRE

    Eszter D Schoell; Ulrike Bingel; Falk Eippert; Juliana Yacubian; Kerrin Christiansen; Hilke Andresen; Arne May; Christian Buechel

    2010-01-01

    The endogenous opioid system represents one of the principal systems in the modulation of pain. This has been demonstrated in studies of placebo analgesia and stress-induced analgesia, where anti-nociceptive activity triggered by pain itself or by cognitive states is blocked by opioid antagonists. The aim of this study was to characterize the effect of opioid receptor blockade on the physiological processing of painful thermal stimulation in the absence of cognitive manipulation. We therefore...

  14. BLOCKADE OF CENTRAL NICOTINE ACETYLCHOLINE RECEPTOR SIGNALING ATTENUATE GHRELIN-INDUCED FOOD INTAKE IN RODENTS

    OpenAIRE

    S.L. Dickson; Hrabovszky, E; Hansson, C.; Jerlhag, E.; Alvarez-Crespo, M.; Skibicka, K. P.; Molnar, C. S.; Liposits, Z; Engel, J. A.; Egecioglu, E.

    2010-01-01

    Here we sought to determine whether ghrelin's central effects on food intake can be interrupted by nicotinic cholinergic receptor (nAChR) blockade. Ghrelin regulates mesolimbic dopamine neurons projecting from the ventral tegmental area (VTA) to the nucleus accumbens (NAcc), partly via cholinergic VTA afferents originating in the laterodorsal tegmental area (LDTg). Given that these cholinergic projections to the VTA have been implicated in natural as well as drug-induced reinforcement, we sou...

  15. Blockade of Ethanol Reward by the Kappa Opioid Receptor Agonist U50,488h

    OpenAIRE

    Logrip, Marian L.; Janak, Patricia H; Ron, Dorit

    2009-01-01

    Alcoholism is a pervasive social problem, and thus understanding factors which regulate alcohol (ethanol) reward is important for designing effective therapies. One putative regulatory system includes the kappa opioid receptor (KOR) and its endogenous ligand, dynorphin. Previously we demonstrated that acute ethanol increased preprodynorphin expression via brain-derived neurotrophic factor (BDNF) in striatal neurons, and that blockade of the KOR attenuated decreases in ethanol intake observed ...

  16. Evidence for improved cardiac performance after beta-blockade in patients with coronary artery disease.

    Science.gov (United States)

    Reale, A; Nigri, A; Gioffrè, P A

    1976-01-01

    The study was undertaken to investigate the acute haemodynamic effects of bunitrolol (0-2-hydroxy-3-(tert.butylamino)-propoxy)-bity. Right and left heart catheterization was performed in eleven patients with documented coronary artery disease. After bunitrolol (10 mg i.v.), there was a statistically significant decrease in left ventricular and aortic systolic pressures left ventricular end-diastolic pressure, aortic diastolic and mean pressures, pressure-rate product and compliance index (delta P/delta V). Left ventricular dp/dt, left ventricular dp/dt over isovolumic pressure, systemic resistance and heart rate tended to decrease, stroke volume and left ventricular stroke work index tended to increase, without statistical significance. Cardiac index showed individual variations, the mean values for the group being unchanged. Correlation of left ventricular end-diastolic pressure and left ventricular stroke work index showed a shift toward improved ventricular function curve in most cases, deterioration in no instance. Supine exercise was performed in ten patients. Angina occurred in nine patients; in five only before and in four before and after beta-blockade. Post-drug exercise heart rate, pressure-rate product and left ventricular end-diastolic pressure were significantly lower, the latter also in the four patients who still presented exercise angina. It is concluded that certain beta-blockers can improve cardiac performance at rest and during exercise in patients with coronary artery disease. This is explainable on the basis of a more favourable balance between oxygen supply and demand, together with a less marked negative inotropic effect due to the partial agonist activity of the agent used in the study. PMID:18374

  17. Activation of the sympathetic nervous system mediates hypophagic and anxiety-like effects of CB₁ receptor blockade.

    Science.gov (United States)

    Bellocchio, Luigi; Soria-Gómez, Edgar; Quarta, Carmelo; Metna-Laurent, Mathilde; Cardinal, Pierre; Binder, Elke; Cannich, Astrid; Delamarre, Anna; Häring, Martin; Martín-Fontecha, Mar; Vega, David; Leste-Lasserre, Thierry; Bartsch, Dusan; Monory, Krisztina; Lutz, Beat; Chaouloff, Francis; Pagotto, Uberto; Guzman, Manuel; Cota, Daniela; Marsicano, Giovanni

    2013-03-19

    Complex interactions between periphery and the brain regulate food intake in mammals. Cannabinoid type-1 (CB1) receptor antagonists are potent hypophagic agents, but the sites where this acute action is exerted and the underlying mechanisms are not fully elucidated. To dissect the mechanisms underlying the hypophagic effect of CB1 receptor blockade, we combined the acute injection of the CB1 receptor antagonist rimonabant with the use of conditional CB1-knockout mice, as well as with pharmacological modulation of different central and peripheral circuits. Fasting/refeeding experiments revealed that CB1 receptor signaling in many specific brain neurons is dispensable for the acute hypophagic effects of rimonabant. CB1 receptor antagonist-induced hypophagia was fully abolished by peripheral blockade of β-adrenergic transmission, suggesting that this effect is mediated by increased activity of the sympathetic nervous system. Consistently, we found that rimonabant increases gastrointestinal metabolism via increased peripheral β-adrenergic receptor signaling in peripheral organs, including the gastrointestinal tract. Blockade of both visceral afferents and glutamatergic transmission in the nucleus tractus solitarii abolished rimonabant-induced hypophagia. Importantly, these mechanisms were specifically triggered by lipid-deprivation, revealing a nutrient-specific component acutely regulated by CB1 receptor blockade. Finally, peripheral blockade of sympathetic neurotransmission also blunted central effects of CB1 receptor blockade, such as fear responses and anxiety-like behaviors. These data demonstrate that, independently of their site of origin, important effects of CB1 receptor blockade are expressed via activation of peripheral sympathetic activity. Thus, CB1 receptors modulate bidirectional circuits between the periphery and the brain to regulate feeding and other behaviors.

  18. Effect of beta-adrenergic blockade on elevated arterial compliance and low systemic vascular resistance in cirrhosis

    DEFF Research Database (Denmark)

    Møller, S; Bendtsen, F; Henriksen, Jens Henrik Sahl

    2001-01-01

    beta-blockers, but the effect of this treatment on arterial compliance has not been investigated. The aim of the present study was therefore to assess the effects of propranolol on the arterial compliance of patients with cirrhosis. METHODS: Twenty patients with cirrhosis underwent a haemodynamic......) of 17.8 mmHg, and responded to beta-blocker treatment with a significant reduction in the HVPG (-16%; P < 0.001). Arterial compliance was elevated (1.27 versus controls 1.01 ml/mmHg; P < 0.001), but remained almost unchanged during beta-adrenergic blockade (1.27 versus 1.29 ml/mmHg, +2%, ns), whereas...... beta-blockers increases small vessel (arteriolar) vascular tone towards the normal level, but does not affect the elevated compliance of the larger arteries in patients with cirrhosis....

  19. CSF1 Receptor Targeting In Prostate Cancer Reverses Macrophage-Mediated Resistance To Androgen Blockade Therapy

    Science.gov (United States)

    Escamilla, Jemima; Schokrpur, Shiruyeh; Liu, Connie; Priceman, Saul J.; Moughon, Diana; Jiang, Ziyue; Pouliot, Frederic; Magyar, Clara; Sung, James L.; Xu, Jingying; Deng, Gang; West, Brian L.; Bollag, Gideon; Fradet, Yves; Lacombe, Louis; Jung, Michael E.; Huang, Jiaoti; Wu, Lily

    2015-01-01

    Growing evidence suggests that tumor-associated macrophages (TAMs) promote cancer progression and therapeutic resistance by enhancing angiogenesis, matrix-remodeling and immunosuppression. In this study prostate cancer (PCa) under androgen blockade therapy (ABT) was investigated, demonstrating that TAMs contribute to PCa disease recurrence through paracrine signaling processes. ABT induced the tumor cells to express macrophage colony-stimulating factor 1 (M-CSF-1 or CSF-1) and other cytokines that recruit and modulate macrophages, causing a significant increase in TAM infiltration. Inhibitors of CSF-1 signaling through its receptor, CSF-1R, were tested in combination with ABT, demonstrating that blockade of TAM influx in this setting disrupts tumor promotion and sustains a more durable therapeutic response compared to ABT alone. PMID:25736687

  20. Oncogenic fingerprint of epidermal growth factor receptor pathway and emerging epidermal growth factor receptor blockade resistance in colorectal cancer

    Science.gov (United States)

    Sobani, Zain A; Sawant, Ashwin; Jafri, Mikram; Correa, Amit Keith; Sahin, Ibrahim Halil

    2016-01-01

    Epidermal growth factor receptor (EGFR) has been an attractive target for treatment of epithelial cancers, including colorectal cancer (CRC). Evidence from clinical trials indicates that cetuximab and panitumumab (anti-EGFR monoclonal antibodies) have clinical activity in patients with metastatic CRC. The discovery of intrinsic EGFR blockade resistance in Kirsten RAS (KRAS)-mutant patients led to the restriction of anti-EGFR antibodies to KRAS wild-type patients by Food and Drug Administration and European Medicine Agency. Studies have since focused on the evaluation of biomarkers to identify appropriate patient populations that may benefit from EGFR blockade. Accumulating evidence suggests that patients with mutations in EGFR downstream signaling pathways including KRAS, BRAF, PIK3CA and PTEN could be intrinsically resistant to EGFR blockade. Recent whole genome studies also suggest that dynamic alterations in signaling pathways downstream of EGFR leads to distinct oncogenic signatures and subclones which might have some impact on emerging resistance in KRAS wild-type patients. While anti-EGFR monoclonal antibodies have a clear potential in the management of a subset of patients with metastatic CRC, further studies are warranted to uncover exact mechanisms related to acquired resistance to EGFR blockade. PMID:27777877

  1. Age dependence of the rapid antidepressant and synaptic effects of acute NMDA receptor blockade

    Directory of Open Access Journals (Sweden)

    Elena eNosyreva

    2014-12-01

    Full Text Available Ketamine is a NMDA receptor antagonist that produces rapid antidepressant responses in individuals with major depressive disorder. The antidepressant action of ketamine has been linked to blocking NMDA receptor activation at rest, which inhibits eukaryotic elongation factor2 kinase leading to desuppression of protein synthesis and synaptic potentiation in the CA1 region of the hippocampus. Here, we investigated ketamine mediated antidepressant response and the resulting synaptic potentiation in juvenile animals. We found that ketamine did not produce an antidepressant response in juvenile animals in the novelty suppressed feeding or the forced swim test. In addition ketamine application failed to trigger synaptic potentiation in hippocampal slices obtained from juvenile animals, unlike its action in slices from older animals (6-9 weeks old. The inability of ketamine to trigger an antidepressant response or subsequent synaptic plasticity processes suggests a developmental component to ketamine mediated antidepressant efficacy. We also show that the NMDAR antagonist AP5 triggers synaptic potentiation in mature hippocampus similar to the action of ketamine, demonstrating that global competitive blockade of NMDA receptors is sufficient to trigger this effect. These findings suggest that global blockade of NMDA receptors in developmentally mature hippocampal synapses are required for the antidepressant efficacy of ketamine.

  2. Histamine H2 receptor blockade augments blood pressure responses to acute submaximal exercise in males.

    Science.gov (United States)

    Doh, Hyung-Woo; Stebbins, Charles L; Choi, Hyun-Min; Park, Joonsung; Nho, Hosung; Kim, Jong-Kyung

    2016-06-01

    Histamine is a potent vasodilator that has been found to increase during exercise. We tested the hypothesis that histamine would attenuate blood pressure (BP), cardiac output (CO), and vascular resistance responses to short-term, submaximal dynamic exercise during H2 receptor blockade. Fourteen healthy men (20-29 years of age) were studied. Systolic (SBP), diastolic (DBP), and mean arterial (MAP) BP and heart rate (HR) were assessed at rest and during the last minute of 10 min of submaximal cycling exercise (60% of peak oxygen consumption) in the absence and presence of histamine H2 receptor blockade (ranitidine, 300 mg). Stroke volume (SV) (impedance cardiography) and plasma norepinephrine (NE) were measured, and CO, rate × pressure product (RPP), and total peripheral resistance (TPR) were calculated. Plasma levels of histamine were also measured. H2 blockade had no effects on any variables at rest. During exercise, SBP (184 ± 3 mm Hg vs. 166 ± 2 mm Hg), MAP (121 ± 2 mm Hg vs. 112 ± 5 mm Hg), and RPP (25.9 ± 0.8 × 10(3) mm Hg·beats/min vs. 23.5 ± 0.8 × 10(3) mm Hg/beats·min) were greater during blocked conditions (P < 0.05), and an interaction was observed for TPR. SV, DBP, HR, and NE levels were unaffected by blockade. Plasma histamine increased from 1.83 ± 0.14 ng/mL at rest to 2.33 ± 0.23 ng/mL during exercise (P < 0.05) and was not affected by H2 blockade (1.56 ± 0.23 ng/mL vs. 1.70 ± 0.24 ng/mL). These findings suggest that, during submaximal exercise, histamine attenuates BP, vascular resistance, and the work of the heart via activation of H2 receptors and that these effects occurred primarily in the vasculature and not in the myocardium. PMID:27191340

  3. Blockade of Vascular Endothelial Growth Factor Receptor 1 Prevents Inflammation and Vascular Leakage in Diabetic Retinopathy

    Directory of Open Access Journals (Sweden)

    Jianbo He

    2015-01-01

    Full Text Available Diabetic retinopathy (DR is a leading cause of blindness in working age adults. The objective of this study is to investigate the effects of vascular endothelial growth factor receptor 1 (VEGFR1 blockade on the complications of DR. Experimental models of diabetes were induced with streptozotocin (STZ treatment or Insulin2 gene mutation (Akita in mice. Protein expression and localization were examined by western blots (WB and immunofluorescence (IF. mRNA expression was quantified by PCR array and real-time PCR. The activity of VEGFR1 signaling was blocked by a neutralizing antibody called MF1. Vascular leakage was evaluated by measuring the leakage of [3H]-mannitol tracer into the retina and the IF staining of albumin. VEGFR1 blockade significantly inhibited diabetes-related vascular leakage, leukocytes-endothelial cell (EC adhesion (or retinal leukostasis, expression of intercellular adhesion molecule- (ICAM- 1 protein, abnormal localization and degeneration of the tight junction protein zonula occludens- (ZO- 1, and the cell adhesion protein vascular endothelial (VE cadherin. In addition, VEGFR1 blockade interfered with the gene expression of 10 new cytokines and chemokines: cxcl10, il10, ccl8, il1f6, cxcl15, ccl4, il13, ccl6, casp1, and ccr5. These results suggest that VEGFR1 mediates complications of DR and targeting this signaling pathway represents a potential therapeutic strategy for the prevention and treatment of DR.

  4. Is interleukin-6 receptor blockade the Holy Grail for inflammatory diseases?

    DEFF Research Database (Denmark)

    Febbraio, M A; Rose-John, S; Pedersen, B K

    2010-01-01

    Interleukin-6 (IL-6) has been linked to a myriad of diseases associated with inflammation, including rheumatoid arthritis (RA), Crohn's disease, and several types of cancer. In 2009 the US Food and Drug Administration accepted a complete-response submission for the use of Actemra (tocilizumab), t......), the first humanized IL-6 receptor-inhibiting monoclonal antibody, for the treatment of RA. Although this treatment will certainly help in managing inflammatory disorders such as RA, we suggest that side effects of such blockade may be excess weight gain and hyperlipidemia....

  5. The effect of combined glutamate receptor blockade in the NTS on the hypoxic ventilatory response in awake rats differs from the effect of individual glutamate receptor blockade.

    Science.gov (United States)

    Pamenter, Matthew E; Nguyen, Jetson; Carr, John A; Powell, Frank L

    2014-08-01

    Ventilatory acclimatization to hypoxia (VAH) increases the hypoxic ventilatory response (HVR) and causes persistent hyperventilation when normoxia is restored, which is consistent with the occurrence of synaptic plasticity in acclimatized animals. Recently, we demonstrated that antagonism of individual glutamate receptor types (GluRs) within the nucleus tractus solitarii (NTS) modifies this plasticity and VAH (J. Physiol. 592(8):1839-1856); however, the effects of combined GluR antagonism remain unknown in awake rats. To evaluate this, we exposed rats to room air or chronic sustained hypobaric hypoxia (CSH, PiO2 = 70 Torr) for 7-9 days. On the experimental day, we microinjected artificial cerebrospinal fluid (ACSF: sham) and then a "cocktail" of the GluR antagonists MK-801 and DNQX into the NTS. The location of injection sites in the NTS was confirmed by glutamate injections on a day before the experiment and with histology following the experiment. Ventilation was measured in awake, unrestrained rats breathing normoxia or acute hypoxia (10% O2) in 15-min intervals using barometric pressure plethysmography. In control (CON) rats, acute hypoxia increased ventilation; NTS microinjections of GluR antagonists, but not ACSF, significantly decreased ventilation and breathing frequency in acute hypoxia but not normoxia (P NTS significantly decreased ventilation in normoxia and breathing frequency in hypoxia. A persistent HVR after combined GluR blockade in the NTS contrasts with the effect of individual GluR blockade and also with results in anesthetized rats. Our findings support the hypotheses that GluRs in the NTS contribute to, but cannot completely explain, VAH in awake rats.

  6. GABAB receptor blockade enhances theta and gamma rhythms in the hippocampus of behaving rats.

    Science.gov (United States)

    Leung, L Stan; Shen, Bixia

    2007-01-01

    The participation of GABA(B) receptors in hippocampal EEG generation was studied by intracerebroventricular (icv) and intracerebral infusions of GABA(B) receptor antagonist p-(3-aminopropyl)-p-diethoxymethyl-phosphinic acid (CGP35348) in freely behaving rats. During awake-immobility, icv CGP35348 induced a theta rhythm and increased gamma waves (30-100 Hz) in the hippocampus. The immobility theta peaked at 6-7 Hz and had a theta phase in CA1 stratum radiatum of approximately 160 degrees with reference to the theta at the alveus, when compared with approximately 130 degrees during walking. Immobility theta power peaks at 6-7 Hz was also found in normal rats, and it was detected in 27% of the EEG segments during immobility. Incidence of immobility theta increased to 87.5% after 480 nmol of CGP35348 icv. Muscarinic antagonist scopolamine (5 mg/kg, ip) suppressed the induction of immobility theta and the gamma power increase after icv CGP35348. CGP35348 icv did not significantly change the hippocampal theta power at 7-8 Hz during walking (theta fundamental), but it increased power at 12-15 Hz, at the second harmonic of theta. CGP35348 icv also increased 30-50 Hz gamma power during walking. Medial septal infusion of CGP35348 (12 nmol in 0.4 microl) increased the power and the frequency of the hippocampal theta second harmonic during walking, but did not increase gamma activity. Infusion of CGP35348 (8 nmol in 0.4 microl) in the hippocampus increased the local gamma activity at 30-100 Hz, but did not induce immobility theta or affect the walking theta rhythm. In conclusion, icv GABA(B) receptor blockade increased an atropine-sensitive input that generated an immobility theta rhythm, while GABA(B) receptor blockade of the medial septum increased atropine-resistant theta harmonics possibly generated by apical dendritic spikes. GABA(B) receptor blockade may enhance cognitive task performance by activating hippocampal theta and gamma rhythms in behaving rats.

  7. Dual Mechanism of Interleukin-3 Receptor Blockade by an Anti-Cancer Antibody

    Directory of Open Access Journals (Sweden)

    Sophie E. Broughton

    2014-07-01

    Full Text Available Interleukin-3 (IL-3 is an activated T cell product that bridges innate and adaptive immunity and contributes to several immunopathologies. Here, we report the crystal structure of the IL-3 receptor α chain (IL3Rα in complex with the anti-leukemia antibody CSL362 that reveals the N-terminal domain (NTD, a domain also present in the granulocyte-macrophage colony-stimulating factor (GM-CSF, IL-5, and IL-13 receptors, adopting unique “open” and classical “closed” conformations. Although extensive mutational analyses of the NTD epitope of CSL362 show minor overlap with the IL-3 binding site, CSL362 only inhibits IL-3 binding to the closed conformation, indicating alternative mechanisms for blocking IL-3 signaling. Significantly, whereas “open-like” IL3Rα mutants can simultaneously bind IL-3 and CSL362, CSL362 still prevents the assembly of a higher-order IL-3 receptor-signaling complex. The discovery of open forms of cytokine receptors provides the framework for development of potent antibodies that can achieve a “double hit” cytokine receptor blockade.

  8. Ventral Midbrain NMDA Receptor Blockade: From Enhanced Reward and Dopamine Inactivation.

    Science.gov (United States)

    Hernandez, Giovanni; Cossette, Marie-Pierre; Shizgal, Peter; Rompré, Pierre-Paul

    2016-01-01

    Glutamate stimulates ventral midbrain (VM) N-Methyl-D-Aspartate receptors (NMDAR) to initiate dopamine (DA) burst firing activity, a mode of discharge associated with enhanced DA release and reward. Blockade of VM NMDAR, however, enhances brain stimulation reward (BSR), the results can be explained by a reduction in the inhibitory drive on DA neurons that is also under the control of glutamate. In this study, we used fast-scan cyclic voltammetry (FSCV) in anesthetized animals to determine whether this enhancement is associated with a change in phasic DA release in the nucleus accumbens. Rats were implanted with a stimulation electrode in the dorsal-raphe (DR) and bilateral cannulae above the VM and trained to self-administer trains of electrical stimulation. The curve-shift method was used to evaluate the effect of a single dose (0.825 nmol/0.5 μl/side) of the NMDAR antagonist, (2R,4S)-4-(3-Phosphopropyl)-2-piperidinecarboxylic acid (PPPA), on reward. These animals were then anesthetized and DA release was measured during delivery of electrical stimulation before and after VM microinjection of the vehicle followed by PPPA. As expected, phasic DA release and operant responding depended similarly on the frequency of rewarding electrical stimulation. As anticipated, PPPA produced a significant reward enhancement. Unexpectedly, PPPA produced a decrease in the magnitude of DA transients at all tested frequencies. To test whether this decrease resulted from excessive activation of DA neurons, we injected apomorphine 20 min after PPPA microinjection. At a dose (100 μg s.c.) sufficient to reduce DA firing under control conditions, apomorphine restored electrical stimulation-induced DA transients. These findings show that combined electrical stimulation and VM NMDARs blockade induce DA inactivation, an effect that indirectly demonstrates that VM NMDARs blockade enhances reward by potentiating stimulation-induced excitation in the mesoaccumbens DA pathway. PMID:27616984

  9. Insulin-like growth factor-I receptor signaling blockade combined with radiation.

    Science.gov (United States)

    Allen, Gregory W; Saba, Corey; Armstrong, Eric A; Huang, Shyh-Min; Benavente, Sergio; Ludwig, Dale L; Hicklin, Daniel J; Harari, Paul M

    2007-02-01

    Signaling through the insulin-like growth factor-I receptor (IGF-IR) is implicated in cellular proliferation, apoptosis, carcinogenesis, metastasis, and resistance to cytotoxic cancer therapies. Targeted disruption of IGF-IR signaling combined with cytotoxic therapy may therefore yield improved anticancer efficacy over conventional treatments alone. In this study, a fully human anti-IGF-IR monoclonal antibody A12 (ImClone Systems, Inc., New York, NY) is examined as an adjunct to radiation therapy. IGF-IR expression is shown for a diverse cohort of cell lines, whereas targeted IGF-IR blockade by A12 inhibits IGF-IR phosphorylation and activation of the downstream effectors Akt and mitogen-activated protein kinase. Anchorage-dependent proliferation and xenograft growth is inhibited by A12 in a dose-dependent manner, particularly for non-small cell lung cancer lines. Clonogenic radiation survival of H226 and H460 cells grown under anchorage-dependent conditions is impaired by A12, demonstrating a radiation dose-enhancing effect for IGF-IR blockade. Postradiation anchorage-independent colony formation is inhibited by A12 in A549 and H460 cells. In the H460 xenograft model, combining A12 and radiation significantly enhances antitumor efficacy compared with either modality alone. These effects may be mediated by promotion of radiation-induced, double-stranded DNA damage and apoptosis as observed in cell culture. In summary, these results validate IGF-IR signal transduction blockade as a promising strategy to improve radiation therapy efficacy in human tumors, forming a basis for future clinical trials. PMID:17283150

  10. Repeated blockade of mineralocorticoid receptors, but not of glucocorticoid receptors impairs food rewarded spatial learning

    NARCIS (Netherlands)

    Douma, BRK; Korte, SM; Buwalda, B; la Fleur, SE; Bohus, B; Luiten, PGM

    1998-01-01

    Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and

  11. Relevance of dorsal raphe nucleus firing in serotonin 5-HT2C receptor blockade-induced augmentation of SSRIs effects

    NARCIS (Netherlands)

    Sotty, Florence; Folgering, Joost H. A.; Brennum, Lise T.; Hogg, Sandra; Mork, Arne; Hertel, Peter; Cremers, Thomas I. F. H.

    2009-01-01

    Selective serotonin reuptake inhibitors are the most widely prescribed antidepressant drugs. However, they exhibit a slow onset of action, putatively due to the initial decrease in serotonin cell firing mediated via somato-dendritic autoreceptors. Interestingly, blockade of 5-HT2C receptors signific

  12. Muscle-type nicotinic receptor blockade by diethylamine, the hydrophilic moiety of lidocaine

    Directory of Open Access Journals (Sweden)

    Armando eAlberola-Die

    2016-02-01

    Full Text Available Lidocaine bears in its structure both an aromatic ring and a terminal amine, which can be protonated at physiological pH, linked by an amide group. Since lidocaine causes multiple inhibitory actions on nicotinic acetylcholine receptors (nAChRs, this work was aimed to determine the inhibitory effects of diethylamine (DEA, a small molecule resembling the hydrophilic moiety of lidocaine, on Torpedo marmorata nAChRs microtransplanted to Xenopus oocytes. Similarly to lidocaine, DEA reversibly blocked acetylcholine-elicited currents (IACh in a dose-dependent manner (IC50 close to 70 μM, but unlike lidocaine, DEA did not affect IACh desensitization. IACh inhibition by DEA was more pronounced at negative potentials, suggesting an open-channel blockade of nAChRs, although roughly 30% inhibition persisted at positive potentials, indicating additional binding sites outside the pore. DEA block of nAChRs in the resting state (closed channel was confirmed by the enhanced IACh inhibition when pre-applying DEA before its co-application with ACh, as compared with solely DEA and ACh co-application. Virtual docking assays provide a plausible explanation to the experimental observations in terms of the involvement of different sets of drug binding sites. So, at the nAChR transmembrane (TM domain, DEA and lidocaine shared binding sites within the channel pore, giving support to their open-channel blockade; besides, lidocaine, but not DEA, interacted with residues at cavities among the M1, M2, M3 and M4 segments of each subunit and also at intersubunit crevices. At the extracellular (EC domain, DEA and lidocaine binding sites were broadly distributed, which aids to explain the closed channel blockade observed. Interestingly, some DEA clusters were located at the α-γ interphase of the EC domain, in a cavity near the orthosteric binding site pocket; by contrast, lidocaine contacted with all α-subunit loops conforming the ACh binding site, both in α-γ and

  13. Genetic blockade of the dopamine D3 receptor enhances hippocampal expression of PACAP and receptors and alters their cortical distribution.

    Science.gov (United States)

    Marzagalli, R; Leggio, G M; Bucolo, C; Pricoco, E; Keay, K A; Cardile, V; Castorina, S; Salomone, S; Drago, F; Castorina, A

    2016-03-01

    Dopamine D3 receptors (D3Rs) are implicated in several aspects of cognition, but their role in aversive conditioning has only been marginally uncovered. Investigations have reported that blockade of D3Rs enhances the acquisition of fear memories, a phenomenon tightly linked to the neuropeptide pituitary adenylate cyclase-activating peptide (PACAP). However, the impact of D3R ablation on the PACAPergic system in regions critical for the formation of new memories remains unexplored. To address this issue, levels of PACAP and its receptors were compared in the hippocampus and cerebral cortex (CX) of mice devoid of functional D3Rs (D3R(-/-)) and wild-types (WTs) using a series of comparative immunohistochemical and biochemical analyses. Morphometric and stereological data revealed increased hippocampal area and volume in D3R(-/-) mice, and augmented neuronal density in CA1 and CA2/3 subfields. PACAP levels were increased in the hippocampus of D3R(-/-) mice. Expression of PACAP receptors was also heightened in mutant mice. In the CX, PACAP immunoreactivity (IR), was restricted to cortical layer V in WTs, but was distributed throughout layers IV-VI in D3R(-/-) mice, along with increased mRNAs, protein concentration and staining scores. Consistently, PAC1, VPAC1 and VPAC2 IRs were variably redistributed in CX, with a general upregulation in cortical layers II-IV in knockout animals. Our interpretation of these findings is that disturbed dopamine neurotransmission due to genetic D3R blockade may enhance the PACAP/PAC1-VPAC axis, a key endogenous system for the processing of fear memories. This could explain, at least in part, the facilitated acquisition and consolidation of aversive memories in D3R(-/-) mice. PMID:26718601

  14. Anticancer immunotherapy by CTLA-4 blockade: obligatory contribution of IL-2 receptors and negative prognostic impact of soluble CD25.

    Science.gov (United States)

    Hannani, Dalil; Vétizou, Marie; Enot, David; Rusakiewicz, Sylvie; Chaput, Nathalie; Klatzmann, David; Desbois, Melanie; Jacquelot, Nicolas; Vimond, Nadège; Chouaib, Salem; Mateus, Christine; Allison, James P; Ribas, Antoni; Wolchok, Jedd D; Yuan, Jianda; Wong, Philip; Postow, Michael; Mackiewicz, Andrzej; Mackiewicz, Jacek; Schadendorff, Dirk; Jaeger, Dirk; Zörnig, Inka; Hassel, Jessica; Korman, Alan J; Bahjat, Keith; Maio, Michele; Calabro, Luana; Teng, Michele Wl; Smyth, Mark J; Eggermont, Alexander; Robert, Caroline; Kroemer, Guido; Zitvogel, Laurence

    2015-02-01

    The cytotoxic T lymphocyte antigen-4 (CTLA-4)-blocking antibody ipilimumab induces immune-mediated long-term control of metastatic melanoma in a fraction of patients. Although ipilimumab undoubtedly exerts its therapeutic effects via immunostimulation, thus far clinically useful, immunologically relevant biomarkers that predict treatment efficiency have been elusive. Here, we show that neutralization of IL-2 or blocking the α and β subunits of the IL-2 receptor (CD25 and CD122, respectively) abolished the antitumor effects and the accompanying improvement of the ratio of intratumoral T effector versus regulatory cells (Tregs), which were otherwise induced by CTLA-4 blockade in preclinical mouse models. CTLA-4 blockade led to the reduction of a suppressive CD4(+) T cell subset expressing Lag3, ICOS, IL-10 and Egr2 with a concomitant rise in IL-2-producing effector cells that lost FoxP3 expression and accumulated in regressing tumors. While recombinant IL-2 improved the therapeutic efficacy of CTLA-4 blockade, the decoy IL-2 receptor α (IL-2Rα, sCD25) inhibited the anticancer effects of CTLA-4 blockade. In 262 metastatic melanoma patients receiving ipilimumab, baseline serum concentrations of sCD25 represented an independent indicator of overall survival, with high levels predicting resistance to therapy. Altogether, these results unravel a role for IL-2 and IL-2 receptors in the anticancer activity of CTLA-4 blockade. Importantly, our study provides the first immunologically relevant biomarker, namely elevated serum sCD25, that predicts resistance to CTLA-4 blockade in patients with melanoma. PMID:25582080

  15. BLOCKADE OF PGE2, PGD2 RECEPTORS CONFERS PROTECTION AGAINST PREPATENT SCHISTOSOMIASIS MANSONI IN MICE.

    Science.gov (United States)

    Abdel-Ghany, Rasha; Rabia, Ibrahim; El-Ahwany, Eman; Saber, Sameh; Gamal, Rasha; Nagy, Faten; Mahmoud, Olaa; Hamad, Rabab Salem; Barakat, Walled

    2015-12-01

    Schistosomiasis is a chronic disease with considerable social impact. Despite the availability of affordable chemotherapy, drug treatment has not significantly reduced the overall number of disease cases. Among other mechanisms, the parasite produces PGE2 and PGD2 to evade host immune defenses. To investigate the role of PGE2 and PGD2 in schistosomiasis, we evaluated the effects of L-161,982, Ah6809 (PGE2 receptor antagonists alone of combined with each other) and MK-0524 (PGD2 receptor antagonist) during prepatent Schistosoma mansoni infection. Drugs were administered intraperitoneally an hour before and 24 hours after infection of C57BL/6 mice with 100 Schistosoma mansoni cercariae. L-161,982, Ah6809, their combination and MK-0524 caused partial protection against pre-patent S. mansoni infection which was mediated by biasing the immune response towards Th1 phenotype. These results showed that blockade of PGE2 and PGD2 receptors confers partial protection against pre-patent S. mansoni infection in mice and that they may be useful as adjunctive therapy to current anti-schistosomal drugs or vaccines. PMID:26939228

  16. [Effects of blockade of ionotropic glutamate receptors on the development of pentylenetetrazole kindling in mice].

    Science.gov (United States)

    Lukomskaia, N Ia; Lavrent'eva, V V; Starshinova, L A; Zhabko, E P; Gorbunova, L V; Tikhonova, T B; Gmiro, V E; Magazanik, L G

    2005-11-01

    Effects of mono- and dicationic derivatives of adamantane and phenylcyclohexyl on the petyleneterazole-induced (35 mg/kg i. p.) kindling were studied in the experiments on mice. Monocationic derivative of phenylcyclohexyl IEM-1921, effectively retarded the development of kindling beginning the dose 0.0001 microM/kg. Memantine: derivative of adamantane (derivative of adamatane) produced the same effect with 100-fold increased dose. Dicationic derivative ofphenylcyclohexyl: IEM-1925, is able to block equally the open channels of both NMDA and subtype of Ca-permeable AMPA receptors. Its effect on kindling differed markedly from selective NMDA antagonists (IEM-1921 and memantine) in more complicated dose-dependence. The retardation of kindling IEM-1925 was induced at 0.001 microM/kg. On the contrary, a 10-time lower dose: 0.0001 microM/kg, facilitated the development of kindling. The observed difference in the activity of selective NMDA antagonists and the drugs combining anti-NMDA and anti-AMPA potency indicates that both types of ionotropic glutamate receptors are involved in the mechanism of petyleneterazole-induced kindling. The integral effect of channel blockade evoked by drugs seems to be dependent not only upon the ratio of the receptor types but on the kinetics of drug action, too.

  17. Antiremodeling effects on the left ventricle during beta-blockade with metoprolol in the treatment of chronic heart failure

    DEFF Research Database (Denmark)

    Grønning, Bjørn Aaris; Nilsson, J C; Sondergaard, Lars;

    2000-01-01

    index remained unchanged, whereas LV mass index decreased in both groups (175 g/m2 to 160 g/m2 in the placebo group [p = 0.005] and 179 g/m2 to 164 g/m2 in the metoprolol CR/XL group [p = 0.011). CONCLUSIONS: This study is the first randomized study to demonstrate that the beta1-blocker metoprolol CR......OBJECTIVES: The purpose of the study was to investigate the effects of beta1-blockade on left ventricular (LV) size and function for patients with chronic heart failure. BACKGROUND: Large-scale trials have shown that a marked decrease in mortality can be obtained by treatment of chronic heart...... failure with beta-adrenergic blocking agents. Possible mechanisms behind this effect remain yet to be fully elucidated, and previous studies have presented insignificant results regarding suspected LV antiremodeling effects. METHODS: In this randomized, placebo-controlled and double-blind substudy to the...

  18. [Beta-1 adrenoceptor blockade decreases the firing rate to painful stimuli in spinal wide-dynamic range neurons in rats].

    Science.gov (United States)

    Lamothe-Molina, Paul J; Lamothe-Molina, Pedro A; López-Ávila, Alberto

    2014-01-01

    Introducción: la epinefrina/norepinefrina inhibe la transmisión del dolor agudo; empero, no es claro el papel de los receptores beta-adrenérgicos. Por tanto, analizamos si los fármacos de estos receptores modulan la transmisión del dolor agudo mediante registro electrofisiológico unitario extracelular in vivo durante estimulación periférica dolorosa y no dolorosa en ratas. Métodos: estudio longitudinal en el que se cotejaron siete grupos de ratas: control (n = 11): solución salina (0,9 %); EPI (n = 8): 100 mcg epinefrina; agonista beta-1 (n = 8): 125 mcg dobutamina; antagonista beta-1 (n = 9): 100 mcg metoprolol; agonista beta-2 (n = 7): 100 mcg clembuterol; antagonista beta-2 (n = 8): butoxamina 100 mcg; antagonista beta-1 + EPI (n = 10): 100 mcg metoprolol + 100 mcg epinefrina. Se hizo análisis estadístico por medio de ANOVA. Resultados: La epinefrina redujo significativamente la tasa de disparo basal (RDB) en 34.1 % (p neuronas ARD.

  19. Blockade of glucocorticoid receptors improves cutaneous wound healing in stressed mice.

    Science.gov (United States)

    de Almeida, Taís Fontoura; de Castro Pires, Taiza; Monte-Alto-Costa, Andréa

    2016-02-01

    Stress is an important condition of modern life. The successful wound healing requires the execution of three major overlapping phases: inflammation, proliferation, and remodeling, and stress can disturb this process. Chronic stress impairs wound healing through the activation of the hypothalamic-pituitary-adrenal axis, and the glucocorticoids (GCs) hormones have been shown to delay wound closure. Therefore, the aim of this study was to investigate the effects of a GC receptor antagonist (RU486) treatment on cutaneous healing in chronically stressed mice. Male mice were submitted to rotational stress, whereas control animals were not subjected to stress. Stressed and control animals were treated with RU486. A full-thickness excisional lesion was generated, and seven days later, lesions were recovered. The RU486 treatment improves wound healing since contraction takes place earlier in RU486-treated in comparison to non-treated mice, and the RU486 treatment also improves the angiogenesis in Stress+RU486 mice when compared to stressed animals. The Stress+RU486 group showed a decrease in inflammatory cell infiltration and in hypoxia-inducible factor-1α and inducible nitric oxide synthase expression; meanwhile, there was an increase in myofibroblasts quantity. In conclusion, blockade of GC receptors with RU486 partially ameliorates stress-impaired wound healing, suggesting that stress inhibits healing through more than one functional pathway.

  20. Blockade of cannabinoid 1 receptor improves GLP-1R mediated insulin secretion in mice.

    Science.gov (United States)

    González-Mariscal, Isabel; Krzysik-Walker, Susan M; Kim, Wook; Rouse, Michael; Egan, Josephine M

    2016-03-01

    The cannabinoid 1 receptor (CB1) is an important regulator of energy metabolism. Reports of in vivo and in vitro studies give conflicting results regarding its role in insulin secretion, possibly due to circulatory factors, such as incretins. We hypothesized that this receptor may be a regulator of the entero-insular axis. We found that despite lower food consumption and lower body weight postprandial GLP-1 plasma concentrations were increased in CB1(-/-) mice compared to CB1(+/+) mice administered a standard diet or high fat/sugar diet. Upon exogenous GLP-1 treatment, CB1(-/-) mice had increased glucose-stimulated insulin secretion. In mouse insulinoma cells, cannabinoids reduced GLP-1R-mediated intracellular cAMP accumulation and subsequent insulin secretion. Importantly, such effects were also evident in human islets, and were prevented by pharmacologic blockade of CB1. Collectively, these findings suggest a novel mechanism in which endocannabinoids are negative modulators of incretin-mediated insulin secretion. PMID:26724516

  1. The effect of opioid receptor blockade on the neural processing of thermal stimuli.

    Directory of Open Access Journals (Sweden)

    Eszter D Schoell

    Full Text Available The endogenous opioid system represents one of the principal systems in the modulation of pain. This has been demonstrated in studies of placebo analgesia and stress-induced analgesia, where anti-nociceptive activity triggered by pain itself or by cognitive states is blocked by opioid antagonists. The aim of this study was to characterize the effect of opioid receptor blockade on the physiological processing of painful thermal stimulation in the absence of cognitive manipulation. We therefore measured BOLD (blood oxygen level dependent signal responses and intensity ratings to non-painful and painful thermal stimuli in a double-blind, cross-over design using the opioid receptor antagonist naloxone. On the behavioral level, we observed an increase in intensity ratings under naloxone due mainly to a difference in the non-painful stimuli. On the neural level, painful thermal stimulation was associated with a negative BOLD signal within the pregenual anterior cingulate cortex, and this deactivation was abolished by naloxone.

  2. The effect of opioid receptor blockade on the neural processing of thermal stimuli.

    Science.gov (United States)

    Schoell, Eszter D; Bingel, Ulrike; Eippert, Falk; Yacubian, Juliana; Christiansen, Kerrin; Andresen, Hilke; May, Arne; Buechel, Christian

    2010-01-01

    The endogenous opioid system represents one of the principal systems in the modulation of pain. This has been demonstrated in studies of placebo analgesia and stress-induced analgesia, where anti-nociceptive activity triggered by pain itself or by cognitive states is blocked by opioid antagonists. The aim of this study was to characterize the effect of opioid receptor blockade on the physiological processing of painful thermal stimulation in the absence of cognitive manipulation. We therefore measured BOLD (blood oxygen level dependent) signal responses and intensity ratings to non-painful and painful thermal stimuli in a double-blind, cross-over design using the opioid receptor antagonist naloxone. On the behavioral level, we observed an increase in intensity ratings under naloxone due mainly to a difference in the non-painful stimuli. On the neural level, painful thermal stimulation was associated with a negative BOLD signal within the pregenual anterior cingulate cortex, and this deactivation was abolished by naloxone. PMID:20811582

  3. NO-flurbiprofen reduces amyloid-beta, is neuroprotective in cell culture, and enhances cognition in response to cholinergic blockade.

    Science.gov (United States)

    Abdul-Hay, Samer O; Luo, Jia; Ashghodom, Rezene T; Thatcher, Gregory R J

    2009-11-01

    The non-steroidal anti-inflammatory drug flurbiprofen is a selective amyloid lowering agent which has been studied clinically in Alzheimer's disease. HCT-1026 is an ester prodrug of flurbiprofen incorporating a nitrate carrier moiety that in vivo provides NO bioactivity and an improved safety profile. In vitro, HCT-1026 retained the cyclooxygenase inhibitory and non-steroidal anti-inflammatory drug activity of flurbiprofen, but at concentrations at which levels of amyloid-beta 1-42 amino acid were lowered by flurbiprofen, amyloid-beta 1-42 amino acid levels were elevated 200% by HCT-1026. Conversely, at lower concentrations, HCT-1026 behaved as a selective amyloid lowering agent with greater potency than flurbiprofen. The difference in concentration-responses between flurbiprofen and HCT-1026 in vitro suggests different cellular targets; and in no case did a combination of nitrate drug with flurbiprofen provide similar actions. In vivo, HCT-1026 was observed to reverse cognitive deficits induced by scopolamine in two behavioral assays; activity that was also shown by a classical nitrate drug, but not by flurbiprofen. The ability to restore aversive memory and spatial working and reference memory after cholinergic blockade has been demonstrated by other agents that stimulate NO/cGMP signaling. These observations add positively to the preclinical profile of HCT-1026 and NO chimeras in Alzheimer's disease.

  4. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade.

    Science.gov (United States)

    Desposito, Dorinne; Chollet, Catherine; Taveau, Christopher; Descamps, Vincent; Alhenc-Gelas, François; Roussel, Ronan; Bouby, Nadine; Waeckel, Ludovic

    2016-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic mice, we assessed the effect of kinin receptor activation or inhibition by subtype-selective pharmacological agonists (B1R and B2R) and antagonist (B2R) on healing of experimental skin wounds. We also studied effects of agonists and antagonist on keratinocytes and fibroblasts in vitro. Levels of Bdkrb1 (encoding B1R) and Bdkrb2 (encoding B2R) mRNAs increased 1-2-fold in healthy and wounded diabetic skin compared with in non-diabetic skin. Diabetes delayed wound healing. The B1R agonist had no effect on wound healing. In contrast, the B2R agonist impaired wound repair in both non-diabetic and diabetic mice, inducing skin disorganization and epidermis thickening. In vitro, B2R activation unbalanced fibroblast/keratinocyte proliferation and increased keratinocyte migration. These effects were abolished by co-administration of B2R antagonist. Interestingly, in the two mouse models of diabetes, the B2R antagonist administered alone normalized wound healing. This effect was associated with the induction of Ccl2 (encoding monocyte chemoattractant protein 1)/Tnf (encoding tumour necrosis factor α) mRNAs. Thus stimulation of kinin B2 receptor impairs skin wound healing in mice. B2R activation occurs in the diabetic skin and delays wound healing. B2R blockade improves skin wound healing in diabetic mice and is a potential therapeutic approach to diabetic ulcers.

  5. Monitoring of beta-receptor sensitivity in cardiac surgery

    DEFF Research Database (Denmark)

    Yndgaard, S; Lippert, F K; Bigler, Dennis Richard;

    1999-01-01

    To determine the repeatability of the hemodynamic response to repeated isoproterenol challenge doses to validate the standardized isoproterenol sensitivity test as an index of cardiovascular beta-receptor function....

  6. Cerebral oxygenation decreases during exercise in humans with beta-adrenergic blockade

    DEFF Research Database (Denmark)

    Seifert, T.; Rasmussen, P.; Secher, Niels H.;

    2009-01-01

    AIM: Beta-blockers reduce exercise capacity by attenuated increase in cardiac output, but it remains unknown whether performance also relates to attenuated cerebral oxygenation. METHODS: Acting as their own controls, eight healthy subjects performed a continuous incremental cycle test to exhaustion...... with or without administration of the non-selective beta-blocker propranolol. Changes in cerebral blood flow velocity were measured with transcranial Doppler ultrasound and those in cerebral oxygenation were evaluated using near-infrared spectroscopy and the calculated cerebral mitochondrial oxygen...

  7. Effects of angiotensin II receptor blockade on cerebral, cardiovascular, counter-regulatory, and symptomatic responses during hypoglycaemia in patients with type 1 diabetes

    DEFF Research Database (Denmark)

    Færch, Louise H; Thorsteinsson, Birger; Tarnow, Lise;

    2015-01-01

    INTRODUCTION: High spontaneous activity of the renin-angiotensin system (RAS) results in more pronounced cognitive impairment and more prolonged QTc interval during hypoglycaemia in type 1 diabetes. We tested whether angiotensin II receptor blockade improves cerebral and cardiovascular function...

  8. Nicotinic receptor blockade decreases fos immunoreactivity within orexin/hypocretin-expressing neurons of nicotine-exposed rats.

    Science.gov (United States)

    Simmons, Steven J; Gentile, Taylor A; Mo, Lili; Tran, Fionya H; Ma, Sisi; Muschamp, John W

    2016-11-01

    Tobacco smoking is the leading cause of preventable death in the United States. Nicotine is the principal psychoactive ingredient in tobacco that causes addiction. The structures governing nicotine addiction, including those underlying withdrawal, are still being explored. Nicotine withdrawal is characterized by negative affective and cognitive symptoms that enhance relapse susceptibility, and suppressed dopaminergic transmission from ventral tegmental area (VTA) to target structures underlies behavioral symptoms of nicotine withdrawal. Agonist and partial agonist therapies help 1 in 4 treatment-seeking smokers at one-year post-cessation, and new targets are needed to more effectively aid smokers attempting to quit. Hypothalamic orexin/hypocretin neurons send excitatory projections to dopamine (DA)-producing neurons of VTA and modulate mesoaccumbal DA release. The effects of nicotinic receptor blockade, which is commonly used to precipitate withdrawal, on orexin neurons remain poorly investigated and present an attractive target for intervention. The present study sought to investigate the effects of nicotinic receptor blockade on hypothalamic orexin neurons using mecamylamine to precipitate withdrawal in rats. Separate groups of rats were treated with either chronic nicotine or saline for 7-days at which point effects of mecamylamine or saline on somatic signs and anxiety-like behavior were assessed. Finally, tissue from rats was harvested for immunofluorescent analysis of Fos within orexin neurons. Results demonstrate that nicotinic receptor blockade leads to reduced orexin cell activity, as indicated by lowered Fos-immunoreactivity, and suggest that this underlying cellular activity may be associated with symptoms of nicotine withdrawal as effects were most prominently observed in rats given chronic nicotine. We conclude from this study that orexin transmission becomes suppressed in rats upon nicotinic receptor blockade, and that behavioral symptoms associated

  9. Angiotensin Receptor Blockade Increases Pancreatic Insulin Secretion and Decreases Glucose Intolerance during Glucose Supplementation in a Model of Metabolic Syndrome

    OpenAIRE

    Rodriguez, Ruben; Viscarra, Jose A.; Minas, Jacqueline N.; Nakano, Daisuke; Nishiyama, Akira; Ortiz, Rudy M.

    2012-01-01

    Renin-angiotensin system blockade improves glucose intolerance and insulin resistance, which contribute to the development of metabolic syndrome. However, the contribution of impaired insulin secretion to the pathogenesis of metabolic syndrome is not well defined. To assess the contributions of angiotensin receptor type 1 (AT1) activation and high glucose intake on pancreatic function and their effects on insulin signaling in skeletal muscle and adipose tissue, an oral glucose tolerance test ...

  10. Transforming growth factor-β inhibition and endothelin receptor blockade in rats with monocrotaline-induced pulmonary hypertension

    OpenAIRE

    Megalou, Aikaterini J; Glava, Chryssoula; Vilaeti, Agapi D.; Oikonomidis, Dimitrios L; Baltogiannis, Giannis G.; Papalois, Apostolos; Vlahos, Antonios P.; Kolettis, Theofilos M

    2012-01-01

    Transforming growth factor-β (TGF-β) inhibition is an investigational therapy for pulmonary arterial hypertension with promising results in experimental studies. The present work compared this approach with endothelin-receptor blockade and evaluated the effects of combined administration. Pulmonary arterial hypertension was induced by single monocrotaline injection (60 mg/kg) in 75 Wistar rats and 15 rats served as controls. Intervention groups consisted of treatment with an antibody against ...

  11. CB1 receptor blockade counters age-induced insulin resistance and metabolic dysfunction.

    Science.gov (United States)

    Lipina, Christopher; Vaanholt, Lobke M; Davidova, Anastasija; Mitchell, Sharon E; Storey-Gordon, Emma; Hambly, Catherine; Irving, Andrew J; Speakman, John R; Hundal, Harinder S

    2016-04-01

    The endocannabinoid system can modulate energy homeostasis by regulating feeding behaviour as well as peripheral energy storage and utilization. Importantly, many of its metabolic actions are mediated through the cannabinoid type 1 receptor (CB1R), whose hyperactivation is associated with obesity and impaired metabolic function. Herein, we explored the effects of administering rimonabant, a selective CB1R inverse agonist, upon key metabolic parameters in young (4 month old) and aged (17 month old) adult male C57BL/6 mice. Daily treatment with rimonabant for 14 days transiently reduced food intake in young and aged mice; however, the anorectic response was more profound in aged animals, coinciding with a substantive loss in body fat mass. Notably, reduced insulin sensitivity in aged skeletal muscle and liver concurred with increased CB1R mRNA abundance. Strikingly, rimonabant was shown to improve glucose tolerance and enhance skeletal muscle and liver insulin sensitivity in aged, but not young, adult mice. Moreover, rimonabant-mediated insulin sensitization in aged adipose tissue coincided with amelioration of low-grade inflammation and repressed lipogenic gene expression. Collectively, our findings indicate a key role for CB1R in aging-related insulin resistance and metabolic dysfunction and highlight CB1R blockade as a potential strategy for combating metabolic disorders associated with aging. PMID:26757949

  12. Blockade of IL-36 receptor signaling does not prevent from TNF-induced arthritis.

    Directory of Open Access Journals (Sweden)

    Anja Derer

    Full Text Available INTRODUCTION: Interleukin (IL-36α is a newly described member of the IL-1 cytokine family with a known inflammatory and pathogenic function in psoriasis. Recently, we could demonstrate that the receptor (IL-36R, its ligand IL-36α and its antagonist IL-36Ra are expressed in synovial tissue of arthritis patients. Furthermore, IL-36α induces MAP-kinase and NFκB signaling in human synovial fibroblasts with subsequent expression and secretion of pro-inflammatory cytokines. METHODS: To understand the pathomechanism of IL-36 dependent inflammation, we investigated the biological impact of IL-36α signaling in the hTNFtg mouse. Also the impact on osteoclastogenesis by IL-36α was tested in murine and human osteoclast assays. RESULTS: Diseased mice showed an increased expression of IL-36R and IL-36α in inflamed knee joints compared to wildtype controls. However, preventively treating mice with an IL-36R blocking antibody led to no changes in clinical onset and pattern of disease. Furthermore, blockade of IL-36 signaling did not change histological signs of TNF-induced arthritis. Additionally, no alteration on bone homeostasis was observed in ex vivo murine and human osteoclast differentiation assays. CONCLUSION: Thus we conclude that IL-36α does not affect the development of inflammatory arthritis.

  13. Interleukin-7 receptor blockade suppresses adaptive and innate inflammatory responses in experimental colitis

    Directory of Open Access Journals (Sweden)

    Willis Cynthia R

    2012-10-01

    Full Text Available Abstract Background Interleukin-7 (IL-7 acts primarily on T cells to promote their differentiation, survival, and homeostasis. Under disease conditions, IL-7 mediates inflammation through several mechanisms and cell types. In humans, IL-7 and its receptor (IL-7R are increased in diseases characterized by inflammation such as atherosclerosis, rheumatoid arthritis, psoriasis, multiple sclerosis, and inflammatory bowel disease. In mice, overexpression of IL-7 results in chronic colitis, and T-cell adoptive transfer studies suggest that memory T cells expressing high amounts of IL-7R drive colitis and are maintained and expanded with IL-7. The studies presented here were undertaken to better understand the contribution of IL-7R in inflammatory bowel disease in which colitis was induced with a bacterial trigger rather than with adoptive transfer. Methods We examined the contribution of IL-7R on inflammation and disease development in two models of experimental colitis: Helicobacter bilis (Hb-induced colitis in immune-sufficient Mdr1a−/− mice and in T- and B-cell-deficient Rag2−/− mice. We used pharmacological blockade of IL-7R to understand the mechanisms involved in IL-7R-mediated inflammatory bowel disease by analyzing immune cell profiles, circulating and colon proteins, and colon gene expression. Results Treatment of mice with an anti-IL-7R antibody was effective in reducing colitis in Hb-infected Mdr1a−/− mice by reducing T-cell numbers as well as T-cell function. Down regulation of the innate immune response was also detected in Hb-infected Mdr1a−/− mice treated with an anti-IL-7R antibody. In Rag2−/− mice where colitis was triggered by Hb-infection, treatment with an anti-IL-7R antibody controlled innate inflammatory responses by reducing macrophage and dendritic cell numbers and their activity. Conclusions Results from our studies showed that inhibition of IL-7R successfully ameliorated inflammation and disease development

  14. Glucose intolerance induced by blockade of central FGF receptors is linked to an acute stress response

    Science.gov (United States)

    Rojas, Jennifer M.; Matsen, Miles E.; Mundinger, Thomas O.; Morton, Gregory J.; Stefanovski, Darko; Bergman, Richard N.; Kaiyala, Karl J.; Taborsky, Gerald J.; Schwartz, Michael W.

    2015-01-01

    Objective Central administration of ligands for fibroblast growth factor receptors (FGFRs) such as fibroblast growth factor-19 (FGF19) and FGF21 exert glucose-lowering effects in rodent models of obesity and type 2 diabetes (T2D). Conversely, intracerebroventricular (icv) administration of the non-selective FGFR inhibitor (FGFRi) PD173074 causes glucose intolerance, implying a physiological role for neuronal FGFR signaling in glucose homeostasis. The current studies were undertaken to identify neuroendocrine mechanisms underlying the glucose intolerance induced by pharmacological blockade of central FGFRs. Methods Overnight fasted, lean, male, Long-Evans rats received icv injections of either PD173074 or vehicle (Veh) followed 30 min later by performance of a frequently sampled intravenous glucose tolerance test (FSIGT). Minimal model analysis of glucose and insulin data from the FSIGT was performed to estimate insulin-dependent and insulin-independent components of glucose disposal. Plasma levels of lactate, glucagon, corticosterone, non-esterified free fatty acids (NEFA) and catecholamines were measured before and after intravenous (iv) glucose injection. Results Within 20 min of icv PD173074 injection (prior to the FSIGT), plasma levels of lactate, norepinephrine and epinephrine increased markedly, and each returned to baseline rapidly (within 8 min) following the iv glucose bolus. In contrast, plasma glucagon levels were not altered by icv FGFRi at either time point. Consistent with a previous report, glucose tolerance was impaired following icv PD173074 compared to Veh injection and, based on minimal model analysis of FSIGT data, this effect was attributable to reductions of both insulin secretion and the basal insulin effect (BIE), consistent with the inhibitory effect of catecholamines on pancreatic β-cell secretion. By comparison, there were no changes in glucose effectiveness at zero insulin (GEZI) or the insulin sensitivity index (SI). To determine if

  15. Blockade of Cocaine or σ Receptor Agonist Self Administration by Subtype-Selective σ Receptor Antagonists.

    Science.gov (United States)

    Katz, Jonathan L; Hiranita, Takato; Kopajtic, Theresa A; Rice, Kenner C; Mesangeau, Christophe; Narayanan, Sanju; Abdelazeem, Ahmed H; McCurdy, Christopher R

    2016-07-01

    The identification of sigma receptor (σR) subtypes has been based on radioligand binding and, despite progress with σ1R cellular function, less is known about σR subtype functions in vivo. Recent findings that cocaine self administration experience will trigger σR agonist self administration was used in this study to assess the in vivo receptor subtype specificity of the agonists (+)-pentazocine, PRE-084 [2-(4-morpholinethyl) 1-phenylcyclohexanecarboxylate hydrochloride], and 1,3-di-o-tolylguanidine (DTG) and several novel putative σR antagonists. Radioligand binding studies determined in vitro σR selectivity of the novel compounds, which were subsequently studied for self administration and antagonism of cocaine, (+)-pentazocine, PRE-084, or DTG self administration. Across the dose ranges studied, none of the novel compounds were self administered, nor did they alter cocaine self administration. All compounds blocked DTG self administration, with a subset also blocking (+)-pentazocine and PRE-084 self administration. The most selective of the compounds in binding σ1Rs blocked cocaine self administration when combined with a dopamine transport inhibitor, either methylphenidate or nomifensine. These drug combinations did not decrease rates of responding maintained by food reinforcement. In contrast, the most selective of the compounds in binding σ2Rs had no effect on cocaine self administration in combination with either dopamine transport inhibitor. Thus, these results identify subtype-specific in vivo antagonists, and the utility of σR agonist substitution for cocaine self administration as an assay capable of distinguishing σR subtype selectivity in vivo. These results further suggest that effectiveness of dual σR antagonism and dopamine transport inhibition in blocking cocaine self administration is specific for σ1Rs and further support this dual targeting approach to development of cocaine antagonists. PMID:27189970

  16. Blockade of brain angiotensin II AT1 receptors ameliorates stress, anxiety, brain inflammation and ischemia: Therapeutic implications.

    Science.gov (United States)

    Saavedra, Juan M; Sánchez-Lemus, Enrique; Benicky, Julius

    2011-01-01

    Poor adaptation to stress, alterations in cerebrovascular function and excessive brain inflammation play critical roles in the pathophysiology of many psychiatric and neurological disorders such as major depression, schizophrenia, post traumatic stress disorder, Parkinson's and Alzheimer's diseases and traumatic brain injury. Treatment for these highly prevalent and devastating conditions is at present very limited and many times inefficient, and the search for novel therapeutic options is of major importance. Recently, attention has been focused on the role of a brain regulatory peptide, Angiotensin II, and in the translational value of the blockade of its physiological AT(1) receptors. In addition to its well-known cardiovascular effects, Angiotensin II, through AT(1) receptor stimulation, is a pleiotropic brain modulatory factor involved in the control of the reaction to stress, in the regulation of cerebrovascular flow and the response to inflammation. Excessive brain AT(1) receptor activity is associated with exaggerated sympathetic and hormonal response to stress, vulnerability to cerebrovascular ischemia and brain inflammation, processes leading to neuronal injury. In animal models, inhibition of brain AT(1) receptor activity with systemically administered Angiotensin II receptor blockers is neuroprotective; it reduces exaggerated stress responses and anxiety, prevents stress-induced gastric ulcerations, decreases vulnerability to ischemia and stroke, reverses chronic cerebrovascular inflammation, and reduces acute inflammatory responses produced by bacterial endotoxin. These effects protect neurons from injury and contribute to increase the lifespan. Angiotensin II receptor blockers are compounds with a good margin of safety widely used in the treatment of hypertension and their anti-inflammatory and vascular protective effects contribute to reduce renal and cardiovascular failure. Inhibition of brain AT(1) receptors in humans is also neuroprotective

  17. Blockade of lysophosphatidic acid receptors LPAR1/3 ameliorates lung fibrosis induced by irradiation

    International Nuclear Information System (INIS)

    Highlights: → Lysophosphatidic acid (LPA) levels and its receptors LPAR1/3 transcripts were elevated during the development of radiation-induced lung fibrosis. → Lung fibrosis was obviously alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. → VPC12249 administration effectively inhibited radiation-induced fibroblast accumulation in vivo, and suppressed LPA-induced fibroblast proliferation in vitro. → LPA-LPAR1/3 signaling regulated TGFβ1 and CTGF expressions in radiation-challenged lungs, but only influenced CTGF expression in cultured fibroblasts. → LPA-LPAR1/3 signaling induced fibroblast proliferation through a CTGF-dependent pathway, rather than through TGFβ1 activation. -- Abstract: Lung fibrosis is a common and serious complication of radiation therapy for lung cancer, for which there are no efficient treatments. Emerging evidence indicates that lysophosphatidic acid (LPA) and its receptors (LPARs) are involved in the pathogenesis of fibrosis. Here, we reported that thoracic radiation with 16 Gy in mice induced development of radiation lung fibrosis (RLF) accompanied by obvious increases in LPA release and LPAR1 and LPAR3 (LPAR1/3) transcripts. RLF was significantly alleviated in mice treated with the dual LPAR1/3 antagonist, VPC12249. VPC12249 administration effectively prolonged animal survival, restored lung structure, inhibited fibroblast accumulation and reduced collagen deposition. Moreover, profibrotic cytokines in radiation-challenged lungs obviously decreased following administration of VPC12249, including transforming growth factor β1 (TGFβ1) and connective tissue growth factor (CTGF). In vitro, LPA induced both fibroblast proliferation and CTGF expression in a dose-dependent manner, and both were suppressed by blockade of LPAR1/3. The pro-proliferative activity of LPA on fibroblasts was inhibited by siRNA directed against CTGF. Together, our data suggest that the LPA-LPAR1/3 signaling system is involved in the

  18. Changes of lymphocyte beta-adrenergic receptors after surgical stress.

    Science.gov (United States)

    Eandi, M; Buraglio, M; Arduino, C; Viano, I; Sansalvadore, G; Arbinolo, M A

    1984-01-01

    In this study the authors' purpose was to observe the effects of surgical stress on the number of lymphocyte beta-adrenergic receptors in hypertensive and normotensive subjects. It was noticed that after surgery a significant reduction occurred in the number of binding sites of lymphocytes of both hypertensive and normotensive subjects. The time course of recovery to the pre-operative values of binding sites varied between the two groups, being slower in normotensive than in hypertensive patients. This might suggest a different pattern of regulation of the beta-adrenergic receptor between hypertensive and normotensive subjects.

  19. Usefulness of Beta blockade in contemporary management of patients with stable coronary heart disease.

    Science.gov (United States)

    Winchester, David E; Pepine, Carl J

    2014-11-15

    Considerable progress has been made over the last few decades in the management of clinically stable coronary heart disease (SCHD), including improvements in interventions (e.g., percutaneous revascularization), pharmacological management, and risk factor control (e.g., smoking, diet, activity level, hypercholesterolemia, hypertension). Although β blockers have long been used for the treatment of SCHD, their efficacy was established in the era before widespread use of reperfusion interventions, modern medical therapy (e.g., angiotensin-converting enzyme inhibitors, angiotensin receptor blockers), or preventive treatments (e.g., aspirin, statins). On the basis of these older data, β blockers are assumed beneficial, and their use has been extrapolated beyond patients with heart failure and previous myocardial infarction, which provided the best evidence for efficacy. However, there are no randomized clinical trials demonstrating that β blockers decrease clinical events in patients with SCHD in the modern era. Furthermore, these agents are associated with weight gain, problems with glycemic control, fatigue, and bronchospasm, underscoring the fact that their use is not without risk. In conclusion, data are currently lacking to support the widespread use of β blockers for all SCHD patients, but contemporary data suggest that they be reserved for a well-defined high-risk group of patients with evidence of ongoing ischemia, left ventricular dysfunction, heart failure, and perhaps some arrhythmias. PMID:25260949

  20. Usefulness of Beta blockade in contemporary management of patients with stable coronary heart disease.

    Science.gov (United States)

    Winchester, David E; Pepine, Carl J

    2014-11-15

    Considerable progress has been made over the last few decades in the management of clinically stable coronary heart disease (SCHD), including improvements in interventions (e.g., percutaneous revascularization), pharmacological management, and risk factor control (e.g., smoking, diet, activity level, hypercholesterolemia, hypertension). Although β blockers have long been used for the treatment of SCHD, their efficacy was established in the era before widespread use of reperfusion interventions, modern medical therapy (e.g., angiotensin-converting enzyme inhibitors, angiotensin receptor blockers), or preventive treatments (e.g., aspirin, statins). On the basis of these older data, β blockers are assumed beneficial, and their use has been extrapolated beyond patients with heart failure and previous myocardial infarction, which provided the best evidence for efficacy. However, there are no randomized clinical trials demonstrating that β blockers decrease clinical events in patients with SCHD in the modern era. Furthermore, these agents are associated with weight gain, problems with glycemic control, fatigue, and bronchospasm, underscoring the fact that their use is not without risk. In conclusion, data are currently lacking to support the widespread use of β blockers for all SCHD patients, but contemporary data suggest that they be reserved for a well-defined high-risk group of patients with evidence of ongoing ischemia, left ventricular dysfunction, heart failure, and perhaps some arrhythmias.

  1. The role of Estrogen Receptor Beta in Prostate Cancer.

    OpenAIRE

    Christoforou, Paraskevi; Christopoulos, Panagiotis F; Koutsilieris, Michael

    2014-01-01

    Although androgen receptor (AR) signaling is the main molecular tool regulating growth and function of prostate gland, estrogen receptor beta (ERβ) is involved contributive in the differentiation of prostatic epithelial cells and numerous antiproliferative actions on prostate cancer cells. However, ERβ splice variants have been associated with prostate cancer initiation and progression mechanisms. Nowadays, ERß is a promising target as an anticancer therapy and prevention for prostate cancer....

  2. Estrogen receptor beta treats Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    Zhu Tian; Jia Fan; Yang Zhao; Sheng Bi; Lihui Si; Qun Liu

    2013-01-01

    In vitro studies have shown that estrogen receptor β can attenuate the cytotoxic effect of amyloid β protein on PC12 cells through the Akt pathway without estrogen stimulation. In this study, we aimed to observe the effect of estrogen receptor β in Alzheimer's disease rat models established by intraventricular injection of amyloid β protein. Estrogen receptor β lentiviral particles delivered via intraventricular injection increased Akt content in the hippocampus, decreased interleukin-1β mRNA, tumor necrosis factor α mRNA and amyloid β protein levels in the hippocampus, and improved the learning and memory capacities in Alzheimer's disease rats. Estrogen receptor β short hairpin RNA lentiviral particles delivered via intraventricular injection had none of the above impacts on Alzheimer's disease rats. These experimental findings indicate that estrogen receptor β, independent from estrogen, can reduce inflammatory reactions and amyloid β deposition in the hippocampus of Alzheimer's disease rats, and improve learning and memory capacities. This effect may be mediated through activation of the Akt pathway.

  3. DMPD: TGF-beta signaling from receptors to the nucleus. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 10611754 TGF-beta signaling from receptors to the nucleus. Roberts AB. Microbes Inf...leus. PubmedID 10611754 Title TGF-beta signaling from receptors to the nucleus. Authors Roberts AB. Publicat

  4. Glucose intolerance induced by blockade of central FGF receptors is linked to an acute stress response

    Directory of Open Access Journals (Sweden)

    Jennifer M. Rojas

    2015-08-01

    Conclusions: The effect of acute inhibition of central FGFR signaling to impair glucose tolerance likely involves a stress response associated with pronounced, but transient, sympathoadrenal activation and an associated reduction of insulin secretion. Whether this effect is a true consequence of FGFR blockade or involves an off-target effect of the FGFR inhibitor requires additional study.

  5. The disintegrin and metalloproteinase ADAM12 contributes to TGF-beta signaling through interaction with the type II receptor

    DEFF Research Database (Denmark)

    Atfi, Azeddine; Dumont, Emmanuelle; Colland, Frédéric;

    2007-01-01

    Transforming growth factor-beta (TGF-beta) regulates a wide variety of biological processes through two types of Ser/Thr transmembrane receptors: the TGF-beta type I receptor and the TGF-beta type II receptor (TbetaRII). Upon ligand binding, TGF-beta type I receptor activated by TbetaRII propagat...

  6. Brain Angiotensin II Type 1 Receptor Blockade Improves Dairy Blood Pressure Variability via Sympathoinhibition in Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Takuya Kishi

    2015-01-01

    Full Text Available Abnormal blood pressure (BP elevation in early morning is known to cause cardiovascular events. Previous studies have suggested that one of the reasons in abnormal dairy BP variability is sympathoexcitation. We have demonstrated that brain angiotensin II type 1 receptor (AT1R causes sympathoexcitation. The aim of the present study was to investigate whether central AT1R blockade attenuates the excess BP elevation in rest-to-active phase in hypertensive rats or not. Stroke-prone spontaneously hypertensive rats (SHRSP were treated with intracerebroventricular infusion (ICV of AT1R receptor blocker (ARB, oral administration of hydralazine (HYD, or ICV of vehicle (VEH. Telemetric averaged mean BP (MBP was measured at early morning (EM, after morning (AM, and night (NT. At EM, MBP was significantly lower in ARB to a greater extent than in HYD compared to VEH, though MBP at AM was the same in ARB and HYD. At NT, MBP was also significantly lower in ARB than in HYD. These results in MBP were compatible to those in sympathoexcitation and suggest that central AT1R blockade attenuates excess BP elevation in early active phase and continuous BP elevation during rest phase independent of depressor response in hypertensive rats.

  7. THE EFFECTS OF ACUTE AND CHRONIC STRESS ON ERYTHROCYTE DYNAMIC IN COMBINATION WITH ß–ADRENERGIC RECEPTORS BLOCKADE IN RATS

    Directory of Open Access Journals (Sweden)

    Lucian Hritcu

    2005-08-01

    Full Text Available : 3 consecutive days propranolol hydrochloride administration (5 mg/kg b.w., subcutaneous injections under acute and chronic stress conditions causes changes of peripheral erythrocyte distribution in rats. The effects of acute stress and its combination with ȕ-adrenergic receptor blockade on erythrocyte dynamic were more pregnant beside the effects of chronic stress and its combination with ȕ-adrenergic receptor blockade, respectively. ȕ-adrenergic mechanisms were shown to be involved in regulation of erythrocyte dynamic in acute and chronic stress response.

  8. The effects of nucleus accumbens μ-opioid and adenosine 2A receptor stimulation and blockade on instrumental learning.

    Science.gov (United States)

    Clissold, Kara A; Pratt, Wayne E

    2014-11-01

    Prior research has shown that glutamate and dopamine receptors in the nucleus accumbens (NAcc) core are critical for the learning of an instrumental response for food reinforcement. It has also been demonstrated that μ-opioid and adenosine A2A receptors within the NAcc impact feeding and motivational processes. In these experiments, we examined the potential roles of NAcc μ-opioid and A2A receptors on instrumental learning and performance. Sprague-Dawley rats were food restricted and trained to lever press following daily intra-accumbens injections of the A2A receptor agonist CGS 21680 (at 0.0, 6.0, or 24.0ng/side), the A2A antagonist pro-drug MSX-3 (at 0.0, 1.0, or 3.0μg/side), the μ-opioid agonist DAMGO (at 0.0, 0.025, or 0.025μg/side), or the opioid receptor antagonist naltrexone (at 0.0, 2.0 or 20.0μg/side). After five days, rats continued training without drug injections until lever pressing rates stabilized, and were then tested with a final drug test to assess potential performance effects. Stimulation, but not inhibition, of NAcc adenosine A2A receptors depressed lever pressing during learning and performance tests, but did not impact lever pressing on non-drug days. Both μ-opioid receptor stimulation and blockade inhibited learning of the lever-press response, though only naltrexone treatment caused impairments in lever-pressing after the task had been learned. The effect of A2A receptor stimulation on learning and performance were consistent with known effects of adenosine on effort-related processes, whereas the pattern of lever presses, magazine approaches, and pellet consumption following opioid receptor manipulations suggested that their effects may have been driven by drug-induced shifts in the incentive value of the sugar reinforcer. PMID:25101542

  9. Combined, but not individual, blockade of ASIC3, P2X, and EP4 receptors attenuates the exercise pressor reflex in rats with freely perfused hindlimb muscles.

    Science.gov (United States)

    Stone, Audrey J; Copp, Steven W; Kim, Joyce S; Kaufman, Marc P

    2015-12-01

    In healthy humans, tests of the hypothesis that lactic acid, PGE2, or ATP plays a role in evoking the exercise pressor reflex proved controversial. The findings in humans resembled ours in decerebrate rats that individual blockade of the receptors to lactic acid, PGE2, and ATP had only small effects on the exercise pressor reflex provided that the muscles were freely perfused. This similarity between humans and rats prompted us to test the hypothesis that in rats with freely perfused muscles combined receptor blockade is required to attenuate the exercise pressor reflex. We first compared the reflex before and after injecting either PPADS (10 mg/kg), a P2X receptor antagonist, APETx2 (100 μg/kg), an activating acid-sensing ion channel 3 (ASIC) channel antagonist, or L161982 (2 μg/kg), an EP4 receptor antagonist, into the arterial supply of the hindlimb of decerebrated rats. We then examined the effects of combined blockade of P2X receptors, ASIC3 channels, and EP4 receptors on the exercise pressor reflex using the same doses, intra-arterial route, and time course of antagonist injections as those used for individual blockade. We found that neither PPADS (n = 5), APETx2 (n = 6), nor L161982 (n = 6) attenuated the reflex. In contrast, combined blockade of these receptors (n = 7) attenuated the peak (↓27%, P channels, and EP4 receptors on the endings of thin fiber muscle afferents is required to attenuate the exercise pressor reflex in rats with freely perfused hindlimbs. PMID:26472871

  10. Biological significance of glucocorticoid receptor beta

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Alternative splicing of the human glucocorticoid receptor (hGR) primary transcript produces two receptor isoforms, termed hGRα and hGRβ. hGRα is a ligand-activated transcription factor which, in the hormone-bound state, modulates the expression of glucocorticoid-responsive genes by binding to specific glucocorticoid response element (GRE) DNA sequences. In contrast, hGRβ dose not bind glucocorticoids and is transcriptionally inactive. We demonstrate here that hGRβ inhibits the hormone-induced, hGRα-mediated stimulations of gene expression, including glucocorticoid-responsive reporter gene (cat) and endogenous p21 gene. We also demonstrate that hGRβ can inhibit hGRα-mediated regulation of proliferation and differentiation of a human osteosarcoma cell line (HOS-8603). Our studies on the expression of hGR mRNA in nephrotic syndrome patients indicate that the hGRα/hGRβ mRNA ratio in peripheral white blood cell of hormone-resistant patients is lower than that of hormone-sensitive patients and health volunteers. These results indicate that hGRβ may be a physiologically and pathophysiologically relevant endogenous inhibitor of hGRα

  11. The effect of combined glutamate receptor blockade in the NTS on the hypoxic ventilatory response in awake rats differs from the effect of individual glutamate receptor blockade

    OpenAIRE

    Pamenter, Matthew E.; Nguyen, Jetson; Carr, John A.; Powell, Frank L.

    2014-01-01

    Abstract Ventilatory acclimatization to hypoxia (VAH) increases the hypoxic ventilatory response (HVR) and causes persistent hyperventilation when normoxia is restored, which is consistent with the occurrence of synaptic plasticity in acclimatized animals. Recently, we demonstrated that antagonism of individual glutamate receptor types (GluRs) within the nucleus tractus solitarii (NTS) modifies this plasticity and VAH (J. Physiol. 592(8):1839–1856); however, the effects of combined GluR antag...

  12. Characterization of glucagon-like peptide-1 receptor beta-arrestin 2 interaction: a high-affinity receptor phenotype

    DEFF Research Database (Denmark)

    Jorgensen, Rasmus; Martini, Lene; Schwartz, Thue W;

    2005-01-01

    To dissect the interaction between beta-arrestin ((beta)arr) and family B G protein-coupled receptors, we constructed fusion proteins between the glucagon-like peptide 1 receptor and (beta)arr2. The fusion constructs had an increase in apparent affinity selectively for glucagon, suggesting that (...

  13. Incidence of sudden cardiac death associated with coronary artery occlusion in dogs with hypertension and left ventricular hypertrophy is reduced by chronic beta-adrenergic blockade.

    Science.gov (United States)

    Dellsperger, K C; Martins, J B; Clothier, J L; Marcus, M L

    1990-09-01

    Because beta-adrenergic blockade has as one of its many effects altered electrophysiological abnormalities after dogs with left ventricular hypertrophy have been subjected to coronary occlusion, we tested the hypothesis that metoprolol (200-400 mg/day) would reduce mortality rates in dogs with one-kidney, one clip left ventricular hypertrophy while a similar reduction in arterial pressure with enalapril (20-40 mg/day) would not. Dogs with left ventricular hypertrophy were given metoprolol or enalapril for 5-7 days before a 3-hour coronary occlusion. Infarct size and risk area were measured with triphenyltetrazolium chloride stain and barium angiography, respectively. For control (n = 15), left ventricular hypertrophy (n = 17), left ventricular hypertrophy plus metoprolol (n = 12), and left ventricular hypertrophy plus enalapril (n = 15) groups, mean arterial pressure, ratio of infarct size to risk area, and dogs experiencing sudden death were 110 +/- 4, 142 +/- 4, 121 +/- 7, and 120 +/- 3 mm Hg; 44 +/- 5%, 65 +/- 5%, 44 +/- 7%, and 30 +/- 4%; and 27%, 65%, 17%, and 53%, respectively. Thus, the excessive increase in early mortality occurring when dogs with hypertension and left ventricular hypertrophy undergo coronary occlusion is interrupted with beta-blockade, possibly via electrophysiological effects rather than by changes in arterial pressure or infarct size. PMID:1975521

  14. Effects of Bradykinin B2 Receptor Blockade on Infarct Size and Hemodynamics after Myocardial Infarction in Enalapril-treated Rats

    Institute of Scientific and Technical Information of China (English)

    Haizhu Zhang; Changcong Cui; Kexin Du; Jian Liu

    2008-01-01

    Objectives To study the effects of bradykinin (BK) B2 receptor blockade on infarct size and hemodynamics after myocardial infarction (MI) in rats with angiotensin-converting enzyme (ACE) inhibition therapy.Methods MI was produced by ligating the left coronary artery.The effects of enalapril(500μg/kg·day),enalapril(500μg/kg·day) with BK B2 receptor antagonist Hoe-140(500μg/kg·day),angiotensin Ⅱ(Ang Ⅱ) type 1(AT1) receptor antagonist losartan (3 mg/kg·day) on infarct size,left ventricular systolic pressure(LVSP),cardiac output index (CI) and stroke volume index (SVI) were observed in rats after MI.Treatments were started on the 2nd day after MI and continued for another 6 weeks.Results Enalapril reduced infarct size and improved CI and SVI compared with the untreated MI group (P<0.05 ),and these effects of enalapril were significantly blunted by concomitant treatment with Hoe-140 (P<0.05).Losartan was less effective than enalapril.LVSP were unchanged in the three treatment groups.Conclusions BK can reduce infract size and improve hemodynamics in rats following MI.The cardioprotective effects of ACEI partly result from the action of BK exerted through the B2 receptor.

  15. TWEAK and its receptor Fn14 in the synovium of patients with rheumatoid arthritis compared to psoriatic arthritis and its response to tumour necrosis factor blockade

    NARCIS (Netherlands)

    A.W.R. van Kuijk; C.A. Wijbrandts; M. Vinkenoog; T.S. Zheng; K.A. Reedquist; P.P. Tak

    2010-01-01

    Objective: To investigate the expression of tumour necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) and its receptor fibroblast growth factor inducible 14 (Fn14) in the inflamed synovium of patients with arthritis, as TWEAK blockade has been observed to have a beneficial effect in an ani

  16. Remodeling of intrinsic cardiac neurons: effects of β-adrenergic receptor blockade in guinea pig models of chronic heart disease.

    Science.gov (United States)

    Hardwick, Jean C; Southerland, E Marie; Girasole, Allison E; Ryan, Shannon E; Negrotto, Sara; Ardell, Jeffrey L

    2012-11-01

    Chronic heart disease induces remodeling of cardiac tissue and associated neuronal components. Treatment of chronic heart disease often involves pharmacological blockade of adrenergic receptors. This study examined the specific changes in neuronal sensitivity of guinea pig intrinsic cardiac neurons to autonomic modulators in animals with chronic cardiac disease, in the presence or absence of adrenergic blockage. Myocardial infarction (MI) was produced by ligature of the coronary artery and associated vein on the dorsal surface of the heart. Pressure overload (PO) was induced by a banding of the descending dorsal aorta (∼20% constriction). Animals were allowed to recover for 2 wk and then implanted with an osmotic pump (Alzet) containing either timolol (2 mg·kg(-1)·day(-1)) or vehicle, for a total of 6-7 wk of drug treatment. At termination, intracellular recordings from individual neurons in whole mounts of the cardiac plexus were used to assess changes in physiological responses. Timolol treatment did not inhibit the increased sensitivity to norepinephrine seen in both MI and PO animals, but it did inhibit the stimulatory effects of angiotensin II on the norepinephrine-induced increases in neuronal excitability. Timolol treatment also inhibited the increase in synaptically evoked action potentials observed in PO animals with stimulation of fiber tract bundles. These results demonstrate that β-adrenergic blockade can inhibit specific aspects of remodeling within the intrinsic cardiac plexus. In addition, this effect was preferentially observed with active cardiac disease states, indicating that the β-receptors were more influential on remodeling during dynamic disease progression.

  17. Initial evidence that GLP-1 receptor blockade fails to suppress postprandial satiety or promote food intake in humans.

    Science.gov (United States)

    Melhorn, Susan J; Tyagi, Vidhi; Smeraglio, Anne; Roth, Christian L; Schur, Ellen A

    2014-11-01

    Glucagon-like peptide 1 (GLP-1) has incretin effects that are well-documented, but the independent role of GLP-1 action in human satiety perception is debated. We hypothesized that blockade of GLP-1 receptors would suppress postprandial satiety and increase voluntary food intake. After an overnight fast, eight normal weight participants (seven men, BMI 19-24.7 kg/m(2), age 19-29 year) were enrolled in a double-blind, placebo-controlled, randomized crossover study of the GLP-1 antagonist Exendin-[9-39] (Ex-9) to determine if the satiating effects of a meal are dependent on GLP-1 signaling in humans. Following a fasting blood draw, iv infusion of Ex-9 (600-750 pmol/kg/min) or saline began. Thirty minutes later, subjects consumed a standardized breakfast followed 90 min later (at the predicted time of maximal endogenous circulating GLP-1) by an ad libitum buffet meal to objectively measure satiety. Infusions ended once the buffet meal was complete. Visual analog scale ratings of hunger and fullness and serial assessments of plasma glucose, insulin, and GLP-1 concentrations were done throughout the experiment. Contrary to the hypothesis, during Ex-9 infusion subjects reported a greater decrease in hunger due to consumption of the breakfast (Ex-9 -62 ± 5; placebo -41 ± 9; P=0.01) than during placebo. There were no differences in ad libitum caloric intake between Ex-9 and placebo. Ex-9 increased glucose, insulin, and endogenous GLP-1, which may have counteracted any effects of Ex-9 infusion to block satiety signaling. Blockade of GLP-1 receptors failed to suppress subjective satiety following a standardized meal or increase voluntary food intake in healthy, normal-weight subjects.

  18. Efficacy of pre-scan beta-blockade and impact of heart rate on image quality in patients undergoing coronary multidetector computed tomography angiography

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, Michael D. [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Pena, Antonio J.; Nichols, John H. [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Worrell, Stewart [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Bamberg, Fabian [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Dannemann, Nina [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Abbara, Suhny; Cury, Ricardo C.; Brady, Thomas J. [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Hoffmann, Udo [Cardiac MR PET CT Program, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States); Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston MA (United States)], E-mail: uhoffmann@partners.org

    2008-04-15

    Objective: While beta-blockers are routinely administered to patients prior to coronary computed tomography angiography (CTA), their effectiveness is unknown. We therefore assessed the efficacy of beta-blockade with regards to heart rate (HR) control and image quality in an unselected patient cohort. Methods: We studied 150 consecutive patients (104 men/46 female; mean age, 56 {+-} 13 years) referred for coronary CTA. Intravenous metoprolol (5-20 mg) was administered to patients with a HR >65 beats per minute (bpm). The goal HR was defined as an average HR <65 bpm without a single measurement above 68 bpm. Results: Overall, 45% (68/150) of patients met the HR criteria for beta-blocker administration of which 76% (52/68) received metoprolol (mean dose 12 {+-} 10 mg). Of the 52 patients who received beta-blocker versus the 98 who did not, 18 (35%) versus 62 (64%) patients achieved the goal HR, respectively. All patients who achieved the target HR had an evaluable CTA while five patients who did not achieve the target HR had at least one non-evaluable coronary artery due to motion artifact. There was also a significant reduction in any motion artifact among those who achieved the goal HR as compared to those who did not (p = 0.001). Logistic regression revealed an increase in the odds of stair step artifact of 11.6% (95% CI: 2.4% decrease, 27.5% increase) per 1 bpm increase in the standard deviation of scan HR. Conclusion: Overall, efficacy of beta-blocker administration to reach target HR is limited. Improvements in CT scanner temporal resolution are mandatory to achieve consistently high image quality independent of HR and beta-blocker administration.

  19. Measuring specific receptor binding of a PET radioligand in human brain without pharmacological blockade: The genomic plot.

    Science.gov (United States)

    Veronese, Mattia; Zanotti-Fregonara, Paolo; Rizzo, Gaia; Bertoldo, Alessandra; Innis, Robert B; Turkheimer, Federico E

    2016-04-15

    PET studies allow in vivo imaging of the density of brain receptor species. The PET signal, however, is the sum of the fraction of radioligand that is specifically bound to the target receptor and the non-displaceable fraction (i.e. the non-specifically bound radioligand plus the free ligand in tissue). Therefore, measuring the non-displaceable fraction, which is generally assumed to be constant across the brain, is a necessary step to obtain regional estimates of the specific fractions. The nondisplaceable binding can be directly measured if a reference region, i.e. a region devoid of any specific binding, is available. Many receptors are however widely expressed across the brain, and a true reference region is rarely available. In these cases, the nonspecific binding can be obtained after competitive pharmacological blockade, which is often contraindicated in humans. In this work we introduce the genomic plot for estimating the nondisplaceable fraction using baseline scans only. The genomic plot is a transformation of the Lassen graphical method in which the brain maps of mRNA transcripts of the target receptor obtained from the Allen brain atlas are used as a surrogate measure of the specific binding. Thus, the genomic plot allows the calculation of the specific and nondisplaceable components of radioligand uptake without the need of pharmacological blockade. We first assessed the statistical properties of the method with computer simulations. Then we sought ground-truth validation using human PET datasets of seven different neuroreceptor radioligands, where nonspecific fractions were either obtained separately using drug displacement or available from a true reference region. The population nondisplaceable fractions estimated by the genomic plot were very close to those measured by actual human blocking studies (mean relative difference between 2% and 7%). However, these estimates were valid only when mRNA expressions were predictive of protein levels (i

  20. Measuring specific receptor binding of a PET radioligand in human brain without pharmacological blockade: The genomic plot

    Science.gov (United States)

    Veronese, Mattia; Zanotti-Fregonara, Paolo; Rizzo, Gaia; Bertoldo, Alessandra; Innis, Robert B.; Turkheimer, Federico E.

    2016-01-01

    PET studies allow in vivo imaging of the density of brain receptor species. The PET signal, however, is the sum of the fraction of radioligand that is specifically bound to the target receptor and the non-displaceable fraction (i.e. the non-specifically bound radioligand plus the free ligand in tissue). Therefore, measuring the non-displaceable fraction, which is generally assumed to be constant across the brain, is a necessary step to obtain regional estimates of the specific fractions. The nondisplaceable binding can be directly measured if a reference region, i.e. a region devoid of any specific binding, is available. Many receptors are however widely expressed across the brain, and a true reference region is rarely available. In these cases, the nonspecific binding can be obtained after competitive pharmacological blockade, which is often contraindicated in humans. In this work we introduce the genomic plot for estimating the nondisplaceable fraction using baseline scans only. The genomic plot is a transformation of the Lassen graphical method in which the brain maps of mRNA transcripts of the target receptor obtained from the Allen brain atlas are used as a surrogate measure of the specific binding. Thus, the genomic plot allows the calculation of the specific and nondisplaceable components of radioligand uptake without the need of pharmacological blockade. We first assessed the statistical properties of the method with computer simulations. Then we sought ground-truth validation using human PET datasets of seven different neuroreceptor radioligands, where nonspecific fractions were either obtained separately using drug displacement or available from a true reference region. The population nondisplaceable fractions estimated by the genomic plot were very close to those measured by actual human blocking studies (mean relative difference between 2% and 7%). However, these estimates were valid only when mRNA expressions were predictive of protein levels (i

  1. Serotonergic hyperinnervation and effective serotonin blockade in an FGF receptor developmental model of psychosis

    OpenAIRE

    Klejbor, Ilona; Kucinski, Aaron; Wersinger, Scott R.; Corso, Thomas; Spodnik, Jan H.; Dziewiątkowski, Jerzy; Moryś, Janusz; Hesse, Renae A.; Rice, Kenner C.; Miletich, Robert; Stachowiak, Ewa K.; Stachowiak, Michal K.

    2009-01-01

    The role of fibroblast growth factor receptors (FGFR) in normal brain development has been well-documented in transgenic and knock-out mouse models. Changes in FGF and its receptors have also been observed in schizophrenia and related developmental disorders. The current study examines a transgenic th(tk-)/th(tk-) mouse model with FGF receptor signaling disruption targeted to dopamine (DA) neurons, resulting in neurodevelopmental, anatomical, and biochemical alterations similar to those obser...

  2. Expression of transforming growth factor beta (TGF beta) receptors and expression of TGF beta 1, TGF beta 2 and TGF beta 3 in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Damstrup, L; Rygaard, K; Spang-Thomsen, M;

    1993-01-01

    A panel of 21 small cell lung cancer cell (SCLC) lines were examined for the presence of Transforming growth factor beta receptors (TGF beta-r) and the expression of TGF beta mRNAs. By the radioreceptor assay we found high affinity receptors to be expressed in six cell lines. scatchard analysis...... of the binding data demonstrated that the cells bound between 4.5 and 27.5 fmol mg-1 protein with a KD ranging from 16 to 40 pM. TGF beta 1 binding to the receptors was confirmed by cross-linking TGF beta 1 to the TGF beta-r. Three classes of TGF beta-r were demonstrated, type I and type II receptors with M......(r) = 65,000 and 90,000 and the betaglycan (type III) with M(r) = 280,000. Northern blotting showed expression of TGF beta 1 mRNA in ten, TGF beta 2 mRNA in two and TGF beta 3 mRNA in seven cell lines. Our results provide, for the first time, evidence that a large proportion of a broad panel of SCLC cell...

  3. Time course and extent of alpha 1-adrenoceptor density changes in rat heart after beta-adrenoceptor blockade.

    OpenAIRE

    Steinkraus, V.; Nose, M; H. Scholz; Thormählen, K.

    1989-01-01

    1. It has been suggested that impaired beta-adrenoceptor stimulation is a condition under which the functional role of cardiac alpha 1-adrenoceptors is enhanced. We therefore investigated the extent and time course of changes in alpha 1-adrenoceptor characteristics after chronic treatment with the beta-adrenoceptor blocker propranolol in rat heart. For comparison beta-adrenoceptors were also studied. The mechanism of the changes in adrenoceptor density was investigated with cycloheximide, an ...

  4. Local and systemic effects of angiotensin receptor blockade in an emphysema mouse model

    OpenAIRE

    Raupach, Tobias; Lüthje, Lars; Kögler, Harald; de Duve, Christian; Schweda, Frank; Hasenfuß, Gerd; Andreas, Stefan

    2011-01-01

    Abstract Objectives COPD with emphysema causes marked neurohumoral activation. Angiotensin II receptors are highly expressed within the lung and interfere with mechanisms involved in the progression of emphysema. This study examined the effects of an angiotensin II receptor blocker (ARB) on pulmonary and systemic manifestations of emphysema in a mouse model. Methods Female NMRI mice received five intratracheal instillations of porcine pancreatic ela...

  5. Improvement of Chicken Primordial Germ Cell Maintenance In Vitro by Blockade of the Aryl Hydrocarbon Receptor Endogenous Activity.

    Science.gov (United States)

    Pérez Sáez, Juan M; Bussmann, Leonardo E; Barañao, J Lino; Bussmann, Ursula A

    2016-06-01

    Primordial germ cells (PGCs) are the undifferentiated progenitors of gametes. Germline competent PGCs can be developed as a cell-based system for genetic modification in chickens, which provides a valuable tool for transgenic technology with both research and industrial applications. This implies manipulation of PGCs, which, in recent years, encouraged a lot of research focused on the study of PGCs and the way of improving their culture. The aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor that besides mediating toxic responses to environmental contaminants plays pivotal physiological roles in various biological processes. Since a novel compound that acts as an antagonist of this receptor has been reported to promote expansion of hematopoietic stem cells, we conducted the present study with the aim of determining whether addition of an established AHR antagonist to the standard culture medium used nowadays for in vitro chicken PGCs culture improves ex vivo expansion. We have found that addition of α-naphthoflavone in culture medium promotes the amplification of undifferentiated cells and that this effect is exerted by the blockade of AHR action. Our results constitute the first report of the successful use of a readily available AHR antagonist to improve avian PGCs expansion, and they further extend the knowledge of the effects of AHR modulation in undifferentiated cells.

  6. Development and validation of fluorescent receptor assays based on the human recombinant estrogen receptor subtypes alpha and beta

    NARCIS (Netherlands)

    de boer, T; Otjens, D; Muntendam, A; Meulman, E; van Oostijen, M; Ensing, K

    2004-01-01

    This article describes the development and validation of two fluorescent receptor assays for the hRec-estrogen receptor subtypes alpha and beta. As a labelled ligand an autofluorescent phyto-estrogen (coumestrol) has been used. The estrogen receptor (ER) belongs to the nuclear receptor family, a cla

  7. Opioid receptor blockade and warmth-liking: effects on interpersonal trust and frontal asymmetry.

    Science.gov (United States)

    Schweiger, Desirée; Stemmler, Gerhard; Burgdorf, Christin; Wacker, Jan

    2014-10-01

    The emotion 'warmth-liking' (WL) associated with feelings of affection and acceptance is regularly activated in social contexts. WL has been suggested to be more closely related to the consummatory phase of post-goal attainment positive affect than to pre-goal attainment positive affect/approach motivation and to be partly mediated by brain opioids. To validate these assumptions we employed film/imagery to induce either a neutral emotional state or WL in female participants after intake of either placebo or the opioid antagonist naltrexone. Dependent variables were emotion self-report, interpersonal trust (TRUST, i.e. a behavioral indicator of WL) and frontal asymmetry (i.e. an electroencephalogram (EEG) indicator of approach motivation/behavioral activation). We found that participants reported more WL in the placebo/WL group than in the placebo/neutral group and both naltrexone groups. In addition, TRUST increased in the WL group after placebo, but not after naltrexone, and this pattern was reversed in the neutral control groups. Consequently, opioid blockade suppressed or even reversed the effects of the WL induction on the levels of self-report and behavior, respectively. In addition, we observed reduced relative left-frontal asymmetry in the WL (vs neutral) group, consistent with reduced approach motivation. Overall, these results suggest opioidergic influences on WL and TRUST and reduced approach motivation/behavioral activation for the positive emotion WL.

  8. Normotensive sodium loading in normal man: Regulation of renin secretion during beta-receptor blockade

    DEFF Research Database (Denmark)

    Mølstrøm, Simon; Larsen, Nils Heden; Simonsen, Jane Angel;

    2008-01-01

    +/-14 micromol min(-1); 13+/-2 to 55+/-13 micromol min(-1), respectively). Na-loading did not increase plasma atrial natri-uretic peptide (pANP), glomerular filtration rate (GFR by (51)Cr-EDTA), MAP, or cardiac output (CO by impedance cardiography), but increased central venous pressure (CVP) by approxi-mately 2.......0 mmHg (pmmHg. Concomitantly, plasma vasopressin decreased by 30-40% (p

  9. Modulation by group I mGLU receptor activation and group III mGLU receptor blockade of locomotor responses induced by D1-like and D2-like receptor agonists in the nucleus accumbens.

    Science.gov (United States)

    Rouillon, Christophe; Degoulet, Mickael; Chevallier, Karine; Abraini, Jacques H; David, Hélène N

    2008-03-10

    Evidence for functional motor interactions between group I and group III metabotropic glutamatergic (mGlu) receptors and dopamine neurotransmission is now clearly established [David, H.N., Abraini, J.H., 2001a. The group I metabotropic glutamate receptor antagonist S-4-CPG modulates the locomotor response produced by the activation of D1-like, but not D2-like, dopamine receptors in the rat nucleus accumbens. Eur. J. Neurosci. 15, 2157-2164, David, H.N., Abraini, J.H., 2002. Group III metabotropic glutamate receptors and D1-like and D2-like dopamine receptors interact in the rat nucleus accumbens to influence locomotor activity. Eur. J. Neurosci. 15, 869-875]. Nevertheless, whether or not and how, activation of group I and blockade of group III mGlu receptors modulate the motor responses induced by the activation of dopaminergic receptors in the NAcc still remains unknown. Answering this question needs to be assessed since functional interactions between neurotransmitters in the NAcc are well known to depend upon the level of activation of glutamatergic and/or dopaminergic receptors and because the effects of glutamatergic receptor agonists and antagonists on dopaminergic receptor-mediated locomotor responses are not always reciprocal as shown in previous studies. Our results show that activation of group I mGlu receptors by DHPG in the NAcc potentiated the locomotor response induced by intra-NAcc activation of D1-like receptors and blocked those induced by D2-like presynaptic or postsynaptic receptors. Alternatively, blockade of group III mGlu receptors by MPPG in the NAcc potentiated the locomotor responses mediated by D1-like receptors and by D2-like postsynaptic receptors and inhibited that induced by D2-like presynaptic receptors. These results compiled with previous data demonstrate that group I mGlu receptors and group III mGlu receptors can modulate the locomotor responses produced by D1-like and/or D2-like receptor agonists in a complex phasic and tonic

  10. Antidepressant drugs transactivate TrkB neurotrophin receptors in the adult rodent brain independently of BDNF and monoamine transporter blockade.

    Directory of Open Access Journals (Sweden)

    Tomi Rantamäki

    Full Text Available BACKGROUND: Antidepressant drugs (ADs have been shown to activate BDNF (brain-derived neurotrophic factor receptor TrkB in the rodent brain but the mechanism underlying this phenomenon remains unclear. ADs act as monoamine reuptake inhibitors and after prolonged treatments regulate brain bdnf mRNA levels indicating that monoamine-BDNF signaling regulate AD-induced TrkB activation in vivo. However, recent findings demonstrate that Trk receptors can be transactivated independently of their neurotrophin ligands. METHODOLOGY: In this study we examined the role of BDNF, TrkB kinase activity and monoamine reuptake in the AD-induced TrkB activation in vivo and in vitro by employing several transgenic mouse models, cultured neurons and TrkB-expressing cell lines. PRINCIPAL FINDINGS: Using a chemical-genetic TrkB(F616A mutant and TrkB overexpressing mice, we demonstrate that ADs specifically activate both the maturely and immaturely glycosylated forms of TrkB receptors in the brain in a TrkB kinase dependent manner. However, the tricyclic AD imipramine readily induced the phosphorylation of TrkB receptors in conditional bdnf⁻/⁻ knock-out mice (132.4±8.5% of control; P = 0.01, indicating that BDNF is not required for the TrkB activation. Moreover, using serotonin transporter (SERT deficient mice and chemical lesions of monoaminergic neurons we show that neither a functional SERT nor monoamines are required for the TrkB phosphorylation response induced by the serotonin selective reuptake inhibitors fluoxetine or citalopram, or norepinephrine selective reuptake inhibitor reboxetine. However, neither ADs nor monoamine transmitters activated TrkB in cultured neurons or cell lines expressing TrkB receptors, arguing that ADs do not directly bind to TrkB. CONCLUSIONS: The present findings suggest that ADs transactivate brain TrkB receptors independently of BDNF and monoamine reuptake blockade and emphasize the need of an intact tissue context for the

  11. Combined blockade of angiotensin II and prorenin receptors ameliorates podocytic apoptosis induced by IgA-activated mesangial cells.

    Science.gov (United States)

    Leung, Joseph C K; Chan, Loretta Y Y; Saleem, M A; Mathieson, P W; Tang, Sydney C W; Lai, Kar Neng

    2015-07-01

    Glomerulo-podocytic communication plays an important role in the podocytic injury in IgA nephropathy (IgAN). In this study, we examine the role of podocytic angiotensin II receptor subtype 1 (AT1R) and prorenin receptor (PRR) in podocytic apoptosis in IgAN. Polymeric IgA (pIgA) was isolated from patients with IgAN and healthy controls. Conditioned media were prepared from growth arrested human mesangial cells (HMC) incubated with pIgA from patients with IgAN (IgA-HMC media) or healthy controls (Ctl-HMC media). A human podocyte cell line was used as a model to examine the regulation of the expression of AT1R, PRR, TNF-α and CTGF by IgA-HMC media. Podocytic nephrin expression, annexin V binding and caspase 3 activity were used as the functional readout of podocytic apoptosis. IgA-HMC media had no effect on AngII release by podocytes. IgA-HMC media significantly up-regulated the expression of AT1R and PRR, down-regulated nephrin expression and induced apoptosis in podocytes. Mono-blockade of AT1R, PRR, TNF-α or CTGF partially reduced podocytic apoptosis. IgA-HMC media activated NFκB, notch1 and HEY1 expression by podocytes and dual blockade of AT1R with PRR, or anti-TNF-α with anti-CTGF, effectively rescued the podocytic apoptosis induced by IgA-HMC media. Our data suggests that pIgA-activated HMC up-regulates the expression of AT1R and PRR expression by podocytes and the associated activation of NFκB and notch signalling pathways play an essential role in the podocytic apoptosis induced by glomerulo-podocytic communication in IgAN. Simultaneously targeting the AT1R and PRR could be a potential therapeutic option to reduce the podocytic injury in IgAN.

  12. Nicotine reinforcement is reduced by cannabinoid CB1 receptor blockade in the ventral tegmental area.

    Science.gov (United States)

    Simonnet, Amelie; Cador, Martine; Caille, Stephanie

    2013-11-01

    Cannabinoid type 1 (CB1) receptors control the motivational properties and reinforcing effects of nicotine. Indeed, peripheral administration of a CB1 receptor antagonist dramatically decreases both nicotine taking and seeking. However, the neural substrates through which the cannabinoid CB1 receptors regulate the voluntary intake of nicotine remain to be elucidated. In the present study, we sought to determine whether central injections of a CB1 receptor antagonist delivered either into the ventral tegmental area (VTA) or the nucleus accumbens (NAC) may alter nicotine intravenous self-administration (IVSA). Rats were first trained to self-administer nicotine (30 μg/kg/0.1 ml). The effect of central infusions of the CB1 antagonist AM 251 (0, 1 and 10 μg/0.5 μl/side) on nicotine-taking behavior was then tested. Intra-VTA infusions of AM 251 dose dependently reduced IVSA with a significant decrease for the dose 10 μg/0.5 μl/side. Moreover, operant responding for water was unaltered by intra-VTA AM 251 at the same dose. Surprisingly, intra-NAC delivery of AM 251 did not alter nicotine behavior at all. These data suggest that in rats chronically exposed to nicotine IVSA, the cannabinoid CB1 receptors located in the VTA rather than in the NAC specifically control nicotine reinforcement and, subsequently, nicotine-taking behavior. PMID:22784230

  13. Differential effect of NMDA and AMPA receptor blockade on protein synthesis in the rat infarct borderzone

    DEFF Research Database (Denmark)

    Christensen, Thomas; Bruhn, T; Frank, L;

    1996-01-01

    We investigated whether the known neuroprotective effects of two selective glutamate receptor antagonists, the NMDA antagonist MK-801 and the AMPA antagonist NBQX, are reflected in the regional cerebral protein synthesis rates (CPSR) in rats with middle cerebral artery occlusion (MCAO). Rats trea...

  14. [Serumconcentrations of non esterified fatty acids during operative stress and blockade of betaadrenergic receptors (author's transl)].

    Science.gov (United States)

    Knitza, R; Clasen, R; Kunz, C

    1978-11-01

    Every stress reaction leads to an increased, hormonelly induced mobilisation of fatty acids, the extent of which may be considered as a parameter of the aggression mechanism. In 15 patients with idiopathic trigeminal neuralgia, who were operated under neurolepthypalgesia, the problem of quantitative alterations of the concentration pattern of fatty acids was investigated during the operation. In contrast to some reports of the literature, the increase of the concentration of total fatty acids was due to corresponding increases of all individual fatty acids. By preoperative administration of the beta-adrenergic blocking agent Pindolol the increase of fatty acids was reduced without a qualitative shifting of individual fatty acids. PMID:30855

  15. Blockade of the activin receptor IIb activates functional brown adipogenesis and thermogenesis by inducing mitochondrial oxidative metabolism.

    Science.gov (United States)

    Fournier, Brigitte; Murray, Ben; Gutzwiller, Sabine; Marcaletti, Stefan; Marcellin, David; Bergling, Sebastian; Brachat, Sophie; Persohn, Elke; Pierrel, Eliane; Bombard, Florian; Hatakeyama, Shinji; Trendelenburg, Anne-Ulrike; Morvan, Frederic; Richardson, Brian; Glass, David J; Lach-Trifilieff, Estelle; Feige, Jerome N

    2012-07-01

    Brown adipose tissue (BAT) is a key tissue for energy expenditure via fat and glucose oxidation for thermogenesis. In this study, we demonstrate that the myostatin/activin receptor IIB (ActRIIB) pathway, which serves as an important negative regulator of muscle growth, is also a negative regulator of brown adipocyte differentiation. In parallel to the anticipated hypertrophy of skeletal muscle, the pharmacological inhibition of ActRIIB in mice, using a neutralizing antibody, increases the amount of BAT without directly affecting white adipose tissue. Mechanistically, inhibition of ActRIIB inhibits Smad3 signaling and activates the expression of myoglobin and PGC-1 coregulators in brown adipocytes. Consequently, ActRIIB blockade in brown adipose tissue enhances mitochondrial function and uncoupled respiration, translating into beneficial functional consequences, including enhanced cold tolerance and increased energy expenditure. Importantly, ActRIIB inhibition enhanced energy expenditure only at ambient temperature or in the cold and not at thermoneutrality, where nonshivering thermogenesis is minimal, strongly suggesting that brown fat activation plays a prominent role in the metabolic actions of ActRIIB inhibition.

  16. GABAA Receptor Blockade Enhances Memory Consolidation by Increasing Hippocampal BDNF Levels

    OpenAIRE

    Kim, Dong hyun; Kim, Jong Min; Park, Se Jin; Cai, MuDan; Liu, Xiaotong; Lee, Seungheon; Shin, Chan Young; Ryu, Jong Hoon

    2011-01-01

    Memory consolidation is the process by which acquired information is converted to something concrete to be retrieved later. Here we examined a potential role for brain-derived neurotrophic factor (BDNF) in mediating the enhanced memory consolidation induced by the GABAA receptor antagonist, bicuculline methiodide. With the administration of an acquisition trial in naïve mice using a passive avoidance task, mature BDNF (mBDNF) levels were temporally changed in the hippocampal CA1 region, and t...

  17. Prolonged endothelin A receptor blockade attenuates chronic pulmonary hypertension in the ovine fetus.

    OpenAIRE

    Ivy, D. D.; Parker, T A; Ziegler, J W; Galan, H L; Kinsella, J P; Tuder, R M; Abman, S H

    1997-01-01

    Based on past studies of an experimental model of severe intrauterine pulmonary hypertension, we hypothesized that endothelin-1 (ET-1) contributes to high pulmonary vascular resistance (PVR), hypertensive lung structural changes, and right ventricular hypertrophy (RVH) caused by prolonged closure of the ductus arteriosus. To test this hypothesis, we studied the effects of BQ 123, a selective ET(A) receptor antagonist, after ligation of the ductus arteriosus in utero. In 19 late gestation feta...

  18. The effect of purinergic P2 receptor blockade on skeletal muscle exercise hyperemia in miniature swine

    DEFF Research Database (Denmark)

    Mortensen, Stefan Peter; McAllister, R M; Yang, H T;

    2014-01-01

    PURPOSE: ATP could play an important role in skeletal muscle blood flow regulation by inducing vasodilation via purinergic P2 receptors. This study investigated the role of P2 receptors in exercise hyperemia in miniature swine. METHODS: We measured regional blood flow with radiolabeled...... lactate concentration during exercise from 1.6 ± 0.5 to 3.4 ± 0.6 mmol/L and heart rate from 216 ± 12 to 230 ± 9 beats/min, whereas blood pressure was unaltered. Arterial ATP infusion caused a ~twofold increase in blood flow in 15 of the 16 sampled muscle tissues and this effect was abolished after RB2......-microsphere technique and systemic hemodynamics before and after arterial infusion of the P2 receptor antagonist reactive blue 2 during treadmill exercise (5.2 km/h, ~60 % VO2max) and arterial ATP infusion in female Yucatan miniature swine (~29 kg). RESULTS: Mean blood flow during exercise from the 16 sampled skeletal...

  19. Beta-Adrenergic Receptor Expression in Muscle Cells

    Science.gov (United States)

    Young, Ronald B.; Bridge, K.; Vaughn, J. R.

    1999-01-01

    beta-adrenergic receptor (bAR) agonists presumably exert their physiological action on skeletal muscle cells through the bAR. Since the signal generated by the bAR is cyclic AMP (cAMP), experiments were initiated in primary chicken muscle cell cultures to determine if artificial elevation of intracellular cAMP by treatment with forskolin would alter the population of bAR expressed on the surface of muscle cells. Chicken skeletal muscle cells after 7 days in culture were employed for the experiments because muscle cells have attained a steady state with respect to muscle protein metabolism at this stage. Cells were treated with 0-10 uM forskolin for a total of three days. At the end of the 1, 2, and 3 day treatment intervals, the concentration of cAMP and the bAR population were measured. Receptor population was measured in intact muscle cell cultures as the difference between total binding of [H-3]CGP-12177 and non-specific binding of [H-3]CGP-12177 in the presence of 1 uM propranolol. Intracellular cAMP concentration was measured by radioimmunoassay. The concentration of cAMP in forskolin-treated cells increased up to 10-fold in a dose dependent manner. Increasing concentrations of forskolin also led to an increase in (beta)AR population, with a maximum increase of approximately 50% at 10 uM. This increase in (beta)AR population was apparent after only 1 day of treatment, and the pattern of increase was maintained for all 3 days of the treatment period. Thus, increasing the intracellular concentration of cAMP leads to up-regulation of (beta)AR population. Clenbuterol and isoproterenol gave similar effects on bAR population. The effect of forskolin on the quantity and apparent synthesis rate of the heavy chain of myosin (mhc) were also investigated. A maximum increase of 50% in the quantity of mhc was observed at 0.2 UM forskolin, but higher concentrations of forskolin reduced the quantity of mhc back to control levels.

  20. Shared receptor components but distinct complexes for alpha and beta interferons.

    Science.gov (United States)

    Lewerenz, M; Mogensen, K E; Uzé, G

    1998-09-25

    The type I interferon family includes 13 alpha, one omega and one beta subtypes recognized by a complex containing the receptor subunits ifnar1 and ifnar2 and their associated Janus tyrosine kinases, Tyk2 and Jak1. To investigate the reported differences in the way that alpha and beta interferons signal through the receptor, we introduced alanine-substitutions in the ifnar2 extracellular domain, and expressed the mutants in U5A cells, lacking endogenous ifnar2. A selection, designed to recover mutants that responded preferentially to alpha or beta interferon yielded three groups: I, neutral; II, sensitive to alpha interferon, partially resistant to beta interferon; III, resistant to alpha interferon, partially sensitive to beta interferon. A mutant clone, TMK, fully resistant to alpha interferon with good sensitivity to beta interferon, was characterized in detail and compared with U5A cells complemented with wild-type ifnar2 and also with Tyk2-deficient 11.1 cells, which exhibit a similar alpha-unresponsive phenotype with a partial beta interferon response. Using anti-receptor antibodies and mutant forms of beta interferon, three distinct modes of ligand interaction could be discerned: (i) alpha interferon with ifnar1 and ifnar2; (ii) beta interferon with ifnar1 and ifnar2; (iii) beta interferon with ifnar2 alone. We conclude that alpha and beta interferons signal differently through their receptors because the two ligand subtypes interact with the receptor subunits ifnar 1 and ifnar2 in entirely different ways.

  1. Effect of beta-adrenergic blockade on elevated arterial compliance and low systemic vascular resistance in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Bendtsen, Flemming; Henriksen, Jens Henrik

    2001-01-01

    ) of 17.8 mmHg, and responded to beta-blocker treatment with a significant reduction in the HVPG (-16%; P controls 1.01 ml/mmHg; P ... systemic vascular resistance increased substantially (1083 versus 1378 dyn x s x cm-5, +27%; P blood pressure (-6%; P blood flow (-22%; P ... with beta-blockers increases small vessel (arteriolar) vascular tone towards the normal level, but does not affect the elevated compliance of the larger arteries in patients with cirrhosis....

  2. Immune Modulation by Different Types of beta 2 -> 1-Fructans Is Toll-Like Receptor Dependent

    NARCIS (Netherlands)

    Vogt, L.; Ramasamy, U.; Meyer, Diederick; Pullens, G.; Venema, K.; Faas, M.M.; Schols, H.A.; de Vos, P.

    2013-01-01

    Introduction: beta 2 -> 1-fructans are dietary fibers. Main objectives of this study were 1) to demonstrate direct signalling of beta 2 -> 1-fructans on immune cells, 2) to study whether this is mediated by the pattern recognition receptors Toll-like receptors (TLRs) and nucleotide-binding oligomeri

  3. Effects of activation and blockade of dopamine receptors on the extinction of a passive avoidance reaction in mice with a depressive-like state.

    Science.gov (United States)

    Dubrovina, N I; Zinov'eva, D V

    2010-01-01

    Learning and extinction of a conditioned passive avoidance reaction resulting from neuropharmacological actions on dopamine D(1) and D(2) receptors were demonstrated to be specific in intact mice and in mice with a depressive-like state. Learning was degraded only after administration of the D(2) receptor antagonist sulpiride and was independent of the initial functional state of the mice. In intact mice, activation of D(2) receptors with quinpirole led to a deficit of extinction, consisting of a reduction in the ability to acquire new inhibitory learning in conditions associated with the disappearance of the expected punishment. In mice with the "behavioral despair" reaction, characterized by delayed extinction, activation of D(1) receptors with SKF38393 normalized this process, while the D(2) agonist was ineffective. A positive effect consisting of accelerated extinction of the memory of fear of the dark ("dangerous") sector of the experimental chamber was also seen on blockade of both types of dopamine receptor.

  4. [Effects of activation and blockade of dopamine receptors on extinction of passive avoidance response in mice with depressive-like state].

    Science.gov (United States)

    Dubrovina, N I; Zinov'eva, D V

    2008-01-01

    Selectivity of training and extinction of passive avoidance response caused by pharmacological influences on D1 and D2 dopamine receptors in intact mice and mice in depressive-like state was shown. Training was impaired only by administration of D2 receptor antagonist sulpiride and did not depend on the initial functional condition of mice. In intact mice, activation of D2 receptors by quinpirole evoked deficiency of extinction, i.e., impairment of the capability of new inhibitory training under conditions of disappearance of the expected punishment. In mice with reaction of "behavioral despair" characterized by a delay of extinction, activation of D1 receptors by SKF38393 normalized this process (as distinct from the inefficiency of D2 agonist). The positive effect of acceleration of fear memory extinction was revealed also under conditions of blockade of D1 and D2 dopamine receptors.

  5. [Effects of activation and blockade of dopamine receptors on extinction of passive avoidance response in mice with depressive-like state].

    Science.gov (United States)

    Dubrovina, N I; Zinov'eva, D V

    2008-01-01

    Selectivity of training and extinction of passive avoidance response caused by pharmacological influences on D1 and D2 dopamine receptors in intact mice and mice in depressive-like state was shown. Training was impaired only by administration of D2 receptor antagonist sulpiride and did not depend on the initial functional condition of mice. In intact mice, activation of D2 receptors by quinpirole evoked deficiency of extinction, i.e., impairment of the capability of new inhibitory training under conditions of disappearance of the expected punishment. In mice with reaction of "behavioral despair" characterized by a delay of extinction, activation of D1 receptors by SKF38393 normalized this process (as distinct from the inefficiency of D2 agonist). The positive effect of acceleration of fear memory extinction was revealed also under conditions of blockade of D1 and D2 dopamine receptors. PMID:19004320

  6. Effects of activation and blockade of dopamine receptors on the extinction of a passive avoidance reaction in mice with a depressive-like state.

    Science.gov (United States)

    Dubrovina, N I; Zinov'eva, D V

    2010-01-01

    Learning and extinction of a conditioned passive avoidance reaction resulting from neuropharmacological actions on dopamine D(1) and D(2) receptors were demonstrated to be specific in intact mice and in mice with a depressive-like state. Learning was degraded only after administration of the D(2) receptor antagonist sulpiride and was independent of the initial functional state of the mice. In intact mice, activation of D(2) receptors with quinpirole led to a deficit of extinction, consisting of a reduction in the ability to acquire new inhibitory learning in conditions associated with the disappearance of the expected punishment. In mice with the "behavioral despair" reaction, characterized by delayed extinction, activation of D(1) receptors with SKF38393 normalized this process, while the D(2) agonist was ineffective. A positive effect consisting of accelerated extinction of the memory of fear of the dark ("dangerous") sector of the experimental chamber was also seen on blockade of both types of dopamine receptor. PMID:20012492

  7. Improvement of skin wound healing in diabetic mice by kinin B2 receptor blockade

    OpenAIRE

    Desposito, D.; Chollet, C.; Taveau, C.; Descamps, V.; Alhenc-Gelas, F.; Roussel, R.; Bouby, Nadine; Waeckel, L.

    2015-01-01

    Impaired skin wound healing is a major medical problem in diabetic subjects. Kinins exert a number of vascular and other actions limiting organ damage in ischaemia or diabetes, but their role in skin injury is unknown. We investigated, through pharmacological manipulation of bradykinin B1 and B2 receptors (B1R and B2R respectively), the role of kinins in wound healing in non-diabetic and diabetic mice. Using two mouse models of diabetes (streptozotocin-induced and db/db mice) and non-diabetic...

  8. IL-1β Receptor Blockade Protects Islets Against Pro-inflammatory Cytokine Induced Necrosis and Apoptosis

    OpenAIRE

    Schwarznau, Alice; Hanson, Matthew S.; Sperger, Jamie M.; Schram, Brian R; Danobeitia, Juan S.; Greenwood, Krista K.; Vijayan, Ashwanth; Fernandez, Luis A.

    2009-01-01

    Pro-inflammatory cytokines (PIC) impair islet viability and function by activating inflammatory pathways that induce both necrosis and apoptosis. The aim of this study was to utilize an in vitro rat islet model to evaluate the efficacy of a clinically approved IL-1 receptor antagonist (Anakinra) in blocking PIC induced islet impairment. Isolated rat islets were cultured for 48h ± PIC (IL-1β, IFNγ, and TNFα and ±IL-1ra then assayed for cellular integrity by flow cytometry, MAPK phosphorylation...

  9. No significant effect of angiotensin II receptor blockade on intermediate cardiovascular end points in hemodialysis patients

    DEFF Research Database (Denmark)

    Peters, Christian Daugaard; Kjaergaard, Krista D; Jensen, Jens D;

    2014-01-01

    Agents blocking the renin-angiotensin-aldosterone system are frequently used in patients with end-stage renal disease, but whether they exert beneficial cardiovascular effects is unclear. Here the long-term effects of the angiotensin II receptor blocker, irbesartan, were studied in hemodialysis...... the study period significantly correlated with changes in both left ventricular mass and arterial stiffness. Thus, significant effects of irbesartan on intermediate cardiovascular end points beyond blood pressure reduction were absent in hemodialysis patients.Kidney International advance online publication...

  10. The T cell receptor beta genes of Xenopus.

    Science.gov (United States)

    Chretien, I; Marcuz, A; Fellah, J; Charlemagne, J; Du Pasquier, L

    1997-03-01

    cDNA of the T cell receptor beta (TCRB) have been isolated from the anuran amphibian Xenopus and they show strong structural homology to TCRB sequences of other vertebrates. Ten BV families, two D segments, ten J segments, and a single C region have been defined so far. Each V family consists of one to two members per haploid genome. A unique feature of the Xenopus TCRB constant region is the lack of N-linked carbohydrate glycosylation sites. The recombination signal sequences suggest that the mechanism of rearrangements are identical to those of mammals. The locus is inherited in a diploid manner despite the pseudotetraploidy of the Xenopus laevis and X. gilli used in this study. PMID:9079820

  11. Inhibition of angiotensin Ⅱ and blockade of endothelin receptors reduce arterial calcification in rats

    Institute of Scientific and Technical Information of China (English)

    Juxiang LI; Shengying WU; Chunshui PAN; Yongfen QI; Bin GENG; Xiuhua LIU; Chaoshu TANG

    2004-01-01

    Objective To examine whether the two vascular paracrine/autocrine factors, angiotensin Ⅱ (Ang Ⅱ) and endothelin, participate in the pathogenesis of arterial calcification. Methods Nicotine and vitamin D3 treated rats were studied. Vascular calcification was confirmed by using Von Kossa staining, measurement of calcium content,45Ca2+ uptake assay and alkaline phosphatase (ALP) activity. The plasma and vascular Ang Ⅱ and endothelin levels were measured by using radioimmunoassay. Angiotensinogen and endothelin mRNA levels were determined by RTPCR. Results The arterial calcium content, 45Ca2+ uptake and ALP activity were increased in calcification groups compared with control ( P < 0.01 ). Administration of the angiotensin receptor antagonist losartan, the endothelin receptor antagonist bosentan, and the angiotensin-converting enzyme inhibitor captopril reduced significantly the arterial calcium content, 45Ca2+ uptake and ALP activity. In addition, the plasma and aortic Ang Ⅱ and endothelin contents, and vascular angiotensinogen and endothelin mRNA expression were significantly up-regulated ( P <0.05).Conclusions These findings suggest that functional renin-angiotensin system and endothelin pathway are involved in vascular calcification, and that activation of these systems could potentiate pathogenesis of arterial calcification. ( J Geriatr Cardiol 2004;1(2) :108-113. )

  12. The potential role of AT(1)-receptor blockade in the prevention and reversal of atherosclerosis.

    Science.gov (United States)

    Papademetriou, V

    2002-08-01

    The renin-angiotensin system may contribute to the development and progression of atherosclerosis both by increasing blood pressure and by direct effects on all phases of the atherogenic process. Genetic determinants of renin-angiotensin system activation, notably the DD genotype of angiotensin converting enzyme (ACE), are associated with an increased risk of cardiovascular events, as is increased plasma renin activity. In addition, angiotensin II has been shown to increase the uptake and oxidation of low density lipoprotein (LDL) by macrophages and endothelial cells. Angiotensin II also stimulates the production of interleukin 6 and activates the pro-inflammatory factor nuclear factor kappa(B), leading to expression of adhesion molecules and recruitment of monocytes and macrophages, and increases the production of pro-coagulatory factors. In animal experiments, treatment with ACE inhibitors or angiotensin AT(1)-receptor blockers has been shown to have anti-atherogenic effects. Studies with candesartan have shown that this agent produces a dose-dependent reduction in uptake of oxidised LDL by mouse macrophages in vitro, and reduces cholesterol accumulation and atherosclerosis development in the aorta of Watanabe rabbits. These effects were independent of changes in blood pressure. Such findings suggest that AT(1)-receptor blockers may be beneficial in reducing mortality and morbidity resulting from atherosclerotic disease, and are consistent with the findings from large outcome trials with ACE inhibitors in patients at risk of cardiovascular events. PMID:12140726

  13. Conserved structure of amphibian T-cell antigen receptor beta chain.

    Science.gov (United States)

    Fellah, J S; Kerfourn, F; Guillet, F; Charlemagne, J

    1993-07-15

    All jawed vertebrates possess well-differentiated thymuses and elicit T-cell-like cell-mediated responses; however, no surface T-cell receptor (TCR) molecules or TCR genes have been identified in ectothermic vertebrate species. Here we describe cDNA clones from an amphibian species, Ambystoma mexicanum (the Mexican axolotl), that have sequences highly homologous to the avian and mammalian TCR beta chains. The cloned amphibian beta chain variable region (V beta) shares most of the structural characteristics with the more evolved vertebrate V beta and presents approximately 56% amino acid identities with the murine V beta 14 and human V beta 18 families. The two different cloned axolotl beta chain joining regions (J beta) were found to have conserved all the invariant mammalian J beta residues, and in addition, the presence of a conserved glycine at the V beta-J beta junction suggests the existence of diversity elements. The extracellular domains of the two axolotl beta chain constant region isotypes C beta 1 and C beta 2 show an impressively high degree of identity, thus suggesting that a very efficient mechanism of gene correction has been in operation to preserve this structure at least from the early tetrapod evolution. The transmembrane axolotl C beta domains have been less well conserved when compared to the mammalian C beta but they do maintain the lysine residue that is thought to be involved in the charged interaction between the TCR alpha beta heterodimer and the CD3 complex. PMID:8341702

  14. Orexin-1 receptor blockade suppresses compulsive-like alcohol drinking in mice.

    Science.gov (United States)

    Lei, Kelly; Wegner, Scott A; Yu, Ji-Hwan; Hopf, F Woodward

    2016-11-01

    Addiction is promoted by pathological motivation for addictive substances, and, despite extensive efforts, alcohol use disorders (AUDs) continue to extract a very high social, physical, and economic toll. Compulsive drinking of alcohol, where consumption persists even when alcohol is paired with negative consequences, is considered a particular obstacle for treating AUDs. Aversion-resistant alcohol intake in rodents, e.g. where rodents drink even when alcohol is paired with the bitter tastant quinine, has been considered to model some compulsive aspects of human alcohol consumption. However, the critical mechanisms that drive compulsive-like drinking are only beginning to be identified. The neuropeptide orexin has been linked to high motivation for cocaine, preferred foods, and alcohol. Thus, we investigated the role of orexin receptors in compulsive-like alcohol drinking, where C57BL/6 mice had 2-hr daily access to 15% alcohol with or without quinine (100 μM). We found that systemic administration of the widely used selective orexin-1 receptor (OX1R) blocker, SB-334867 (SB), significantly reduced compulsive-like consumption at doses lower than those reported to reduce quinine-free alcohol intake. The dose of 3-mg/kg SB, in particular, suppressed only compulsive-like drinking. Furthermore, SB did not reduce concurrent water intake during the alcohol drinking sessions, and did not alter saccharin + quinine consumption. In addition, the OX2R antagonist TCS-OX2-29 (3 or 10 mg/kg) did not alter intake of alcohol with or without quinine. Together, our results suggest that OX1R signaling is particularly important for promoting compulsive-like alcohol drinking, and that OX1Rs might represent a novel therapy to counteract compulsive aspects of human AUDs. PMID:27523303

  15. Role of human GABA(A) receptor beta3 subunit in insecticide toxicity.

    Science.gov (United States)

    Ratra, G S; Kamita, S G; Casida, J E

    2001-05-01

    The gamma-aminobutyric acid type A (GABA(A)) receptor is the target for the major insecticides alpha-endosulfan, lindane, and fipronil and for many analogs. Their action as chloride channel blockers is directly measured by binding studies with [(3)H]ethynylbicycloorthobenzoate ([(3)H]EBOB). This study tests the hypothesis that GABA(A) receptor subunit composition determines the sensitivity and selectivity of insecticide toxicity. Human receptor subtypes were expressed individually (alpha1, alpha6, beta1, beta3, and gamma2) and in combination in insect Sf9 cells. Binding parameters were similar for [(3)H]EBOB in the beta3 homooligomer, alpha1beta3gamma2 heterooligomer, and native brain membranes, but toxicological profiles were very different. Surprisingly, alpha-endosulfan, lindane, and fipronil were all remarkably potent on the recombinant beta3 homooligomeric receptor (IC50 values of 0.5-2.4 nM), whereas they were similar in potency on the alpha1beta3gamma2 subtype (IC50 values of 16-33 nM) and highly selective on the native receptor (IC50 values of 7.3, 306, and 2470 nM, respectively). The selectivity order for 29 insecticides and convulsants as IC50 ratios for native/beta3 or alpha1beta3gamma2/beta3 was as follows: fipronil > lindane > 19 other insecticides including alpha-endosulfan and picrotoxinin > 4 trioxabicyclooctanes and dithianes (almost nonselective) > tetramethylenedisulfotetramine, 4-chlorophenylsilatrane, or alpha-thujone. Specificity between mammals and insects at the target site (fipronil > lindane > alpha-endosulfan) paralleled that for toxicity. Potency at the native receptor is more predictive for inhibition of GABA-stimulated chloride uptake than that at the beta3 or alpha1beta3gamma2 receptors. Therefore, the beta3 subunit contains the insecticide target and other subunits differentially modulate the binding to confer compound-dependent specificity and selective toxicity.

  16. The human IgA-Fc alpha receptor interaction and its blockade by streptococcal IgA-binding proteins.

    Science.gov (United States)

    Woof, J M

    2002-08-01

    IgA plays a key role in immune defence of the mucosal surfaces. IgA can trigger elimination mechanisms against pathogens through the interaction of its Fc region with Fc alpha Rs (receptors specific for the Fc region of IgA) present on neutrophils, macrophages, monocytes and eosinophils. The human Fc alpha R (CD89) shares homology with receptors specific for the Fc region of IgG (Fc gamma Rs) and IgE (Fc epsilon RIs), but is a more distantly related member of the receptor family. CD89 interacts with residues lying at the interface of the two domains of IgA Fc, a site quite distinct from the homologous regions at the top of IgG and IgE Fc recognized by Fc gamma R and Fc epsilon RI respectively. Certain pathogenic bacteria express surface proteins that bind to human IgA Fc. Experiments with domain-swap antibodies and mutant IgAs indicate that binding of three such proteins (Sir22 and Arp4 of Streptococcus pyogenes and beta protein of group B streptococci) depend on sites in the Fc interdomain region of IgA, the binding region also used by CD89. Further, we have found that the streptococcal proteins can inhibit interaction of IgA with CD89, and have thereby identified a mechanism by which a bacterial IgA-binding protein may modulate IgA effector function. PMID:12196121

  17. Evolution of T cell receptor genes. Extensive diversity of V beta families in the Mexican axolotl.

    Science.gov (United States)

    Fellah, J S; Kerfourn, F; Charlemagne, J

    1994-11-15

    We have cloned 36 different rearranged variable regions (V beta) genes encoding the beta-chain of the T cell receptor in an amphibian species, Ambystoma mexicanum (the Mexican axolotl). Eleven different V beta segments were identified, which can be classified into 9 families on the basis of a minimum of 75% nucleotide identity. All the cloned V beta segments have the canonical features of known mammalian and avian V beta, including conserved residues Cys23, Trp34, Arg69, Tyr90, and Cys92. There seems to be a greater genetic distance between the axolotl V beta families than between the different V beta families of any mammalian species examined to date: most of the axolotl V beta s have fewer than 35% identical nucleotides and the less related families (V beta 4 and V beta 8) have no more than 23.2% identity (13.5% at the amino acid level). Despite their great mutual divergence, several axolotl V beta are sequence-related to some mammalian V beta genes, like the human V beta 13 and V beta 20 segments and their murine V beta 8 and V beta 14 homologues. However, the axolotl V beta 8 and V beta 9 families are not significantly related to any other V beta sequence at the nucleotide level and show limited amino acid similarity to mammalian V alpha, V kappa III, or VH sequences. The detection of nine V beta families among 35 randomly cloned V beta segments suggests that the V beta gene repertoire in the axolotl is probably larger than presently estimated. PMID:7963525

  18. Efficacy of a triple treatment with irradiation, agonistic TRAIL receptor antibodies and EGFR blockade

    Energy Technology Data Exchange (ETDEWEB)

    Niyazi, Maximilian; Marini, Patrizia [Dept. of Radiation Oncology, CCC Tuebingen (Germany); Daniel, Peter T. [Clinical and Molecular Oncology, Charite, Humboldt Univ., Berlin (Germany); Humphreys, Robin [Oncology Research Dept., Human Genome Sciences Inc., Rockville, MD (United States); Jendrossek, Verena [Dept. of Radiation Oncology, CCC Tuebingen (Germany); Dept. of Molecular Cell Biology, Essen (Germany); Belka, Claus [Dept. of Radiation Oncology, CCC Tuebingen (Germany); Dept. of Radiation Oncology, Ludwig Maximilian Univ., Munich (Germany)

    2009-01-15

    Background and purpose: since the efficacy of a single targeted agent in combination with ionizing radiation is limited by putative treatment resistances, a rationally designed triple treatment consisting of an agonistic antibody targeting either TRAIL-R1 (mapatumumab) or TRAIL-R2 (lexatumumab), radiation and an epidermal growth factor receptor-(EGFR-)inhibiting antibody (cetuximab) was tested. Material and methods: induction of apoptosis after triple treatment was determined in Colo205, HCT116 and FaDu cells by Hoechst 33342 stain. The degree of interaction was determined by isobologram analysis. A knockout variant of HCT116 was used to examine Bax dependence of the triple treatment. The role of Akt/PKB signaling was analyzed using the phosphatidylinositol 3-kinase inhibitor LY294002. Clonogenic assays were performed to examine the effect on clonogenic survival of tumor cells. Results: a synergistic effect of radiation, cetuximab and agonistic TRAIL-R antibodies was demonstrated in cell lines derived from colorectal tumors or head-and-neck cancers. The efficacy of this multimodal approach was dependent on Bax and inhibition of Akt/PKB in the cell systems used. The results also show a positive impact on clonogenic cell death in several cell lines. Conclusion: these data suggest that rationally designed multimodal therapy approaches integrating radiation with more than one targeted agent will open new perspectives in radiation oncology. (orig.)

  19. Effect of food on H2-receptor blockade in normal subjects and duodenal ulcer patients.

    Science.gov (United States)

    Merki, H S; Halter, F; Wilder-Smith, C; Allemann, P; Witzel, L; Kempf, M; Roehmel, J; Walt, R P

    1990-02-01

    Two separate studies of 24 hour intragastric acidity were carried out in normal volunteers and duodenal ulcer patients to define the interaction of food and the antisecretory effects of H2-receptor blockers. Both investigations were double blind randomised comparisons using ranitidine 300 mg with either different meal times or ad libitum snacks after an evening meal. Meals taken after drug administration nearly abolished measurable antisectory effects. Median 24 hour pH was 1.3 on placebo, 2.6 when ranitidine was administered after the evening meal and 1.9 when administered before the evening meal. Snacks taken after evening dosing with ranitidine also significantly decreased pharmacodynamic efficacy. During placebo, median night-time pH was 1.3 without snacks and 1.4 with snacks. pH rose to 5.9 during ranitidine treatment when snacks were forbidden but was only 3.1 when snacks were allowed. These findings could be of therapeutic importance and should rationalise dietary advise to patients receiving H2 blockers. The timing of drug administration can be adjusted according to individual life styles.

  20. Chronic CRF1 receptor blockade reduces heroin intake escalation and dependence-induced hyperalgesia.

    Science.gov (United States)

    Park, Paula E; Schlosburg, Joel E; Vendruscolo, Leandro F; Schulteis, Gery; Edwards, Scott; Koob, George F

    2015-03-01

    Opioids represent effective drugs for the relief of pain, yet chronic opioid use often leads to a state of increased sensitivity to pain that is exacerbated during withdrawal. A sensitization of pain-related negative affect has been hypothesized to closely interact with addiction mechanisms. Neuro-adaptive changes occur as a consequence of excessive opioid exposure, including a recruitment of corticotropin-releasing factor (CRF) and norepinephrine (NE) brain stress systems. To better understand the mechanisms underlying the transition to dependence, we determined the effects of functional antagonism within these two systems on hyperalgesia-like behavior during heroin withdrawal utilizing models of both acute and chronic dependence. We found that passive or self-administered heroin produced a significant mechanical hypersensitivity. During acute opioid dependence, systemic administration of the CRF1 receptor antagonist MPZP (20 mg/kg) alleviated withdrawal-induced mechanical hypersensitivity. In contrast, several functional adrenergic system antagonists (clonidine, prazosin, propranolol) failed to alter mechanical hypersensitivity in this state. We then determined the effects of chronic MPZP or clonidine treatment on extended access heroin self-administration and found that MPZP, but not clonidine, attenuated escalation of heroin intake, whereas both drugs alleviated chronic dependence-associated hyperalgesia. These findings suggest that an early potentiation of CRF signaling occurs following opioid exposure that begins to drive both opioid-induced hyperalgesia and eventually intake escalation.

  1. Prorenin/Renin Receptor Blockade Promotes a Healthy Fat Distribution in Obese Mice

    Science.gov (United States)

    Tan, Paul; Blais, Carolane; Nguyen, Thi M.-D.; Schiller, Peter W.; Gutkowska, Jolanta; Lavoie, Julie L.

    2016-01-01

    Objective Administration of the handle region peptide (HRP), a (pro)renin receptor blocker, decreases body weight gain and visceral adipose tissue (VAT) in high-fat/high-carbohydrate (HF/HC) diet-fed mice. The objective of this study was to elucidate potential mechanisms implicated in these observations. Methods Mice were given a normal or a HF/HC diet along with saline or HRP for 10 weeks. Results In HF/HC-fed mice, HRP increased the expression of several enzymes implicated in lipogenesis and lipolysis in subcutaneous fat (SCF) while the expression of the enzyme implicated in the last step of lipogenesis decreased in VAT. A reduction was also observed in circulating free fatty acids in these animals which was accompanied by normalized adipocyte size in VAT and increased adipocyte size in SCF. “Beiging“ is the evolution of a white adipose tissue toward a brown-like phenotype characterized by an increased mitochondrial density and small lipid droplets. HRP increased the expression of’ “beiging” markers in SCF of HF/HC diet-fed mice. Conclusions HRP treatment may favor healthy fat storage in SCF by activating a triglyceride/free fatty acid cycling and “beiging,” which could explain the body weight and fat mass reduction. PMID:27458124

  2. P2X7 receptor blockade protects against cisplatin-induced nephrotoxicity in mice by decreasing the activities of inflammasome components, oxidative stress and caspase-3

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuanyuan; Yuan, Fahuan; Cao, Xuejiao [Department of Nephrology, Xinqiao Hospital, PLA, Third Military Medical University, Chongqing 400037 (China); Zhai, Zhifang [Department of Dermatology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Gang Huang [Department of Medical Genetics, Third Military Medical University, Chongqing 430038 (China); Du, Xiang; Wang, Yiqin; Zhang, Jingbo; Huang, Yunjian; Zhao, Jinghong [Department of Nephrology, Xinqiao Hospital, PLA, Third Military Medical University, Chongqing 400037 (China); Hou, Weiping, E-mail: hwp0518@aliyun.com [Department of Nephrology, Xinqiao Hospital, PLA, Third Military Medical University, Chongqing 400037 (China)

    2014-11-15

    Nephrotoxicity is a common complication of cisplatin chemotherapy and thus limits the use of cisplatin in clinic. The purinergic 2X7 receptor (P2X7R) plays important roles in inflammation and apoptosis in some inflammatory diseases; however, its roles in cisplatin-induced nephrotoxicity remain unclear. In this study, we first assessed the expression of P2X7R in cisplatin-induced nephrotoxicity in C57BL/6 mice, and then we investigated the changes of renal function, histological injury, inflammatory response, and apoptosis in renal tissues after P2X7R blockade in vivo using an antagonist A-438079. Moreover, we measured the changes of nod-like receptor family, pyrin domain containing proteins (NLRP3) inflammasome components, oxidative stress, and proapoptotic genes in renal tissues in cisplatin-induced nephrotoxicity after treatment with A-438079. We found that the expression of P2X7R was significantly upregulated in the renal tubular epithelial cells in cisplatin-induced nephrotoxicity compared with that of the normal control group. Furthermore, pretreatment with A-438079 markedly attenuated the cisplatin-induced renal injury while lightening the histological damage, inflammatory response and apoptosis in renal tissue, and improved the renal function. These effects were associated with the significantly reduced levels of NLRP3 inflammasome components, oxidative stress, p53 and caspase-3 in renal tissues in cisplatin-induced nephrotoxicity. In conclusions, our studies suggest that the upregulated activity of P2X7R might play important roles in the development of cisplatin-induced nephrotoxicity, and P2X7R blockade might become an effective therapeutic strategy for this disease. - Highlights: • The P2X7R expression was markedly upregulated in cisplatin-induced nephrotoxicity. • P2X7R blockade significantly attenuated the cisplatin-induced renal injury. • P2X7R blockade reduced activities of NLRP3 inflammasome components in renal tissue. • P2X7R blockade

  3. Attenuation of Myocardial Injury by HMGB1 Blockade during Ischemia/Reperfusion Is Toll-Like Receptor 2-Dependent

    Directory of Open Access Journals (Sweden)

    Jan Mersmann

    2013-01-01

    Full Text Available Genetic or pharmacological ablation of toll-like receptor 2 (TLR2 protects against myocardial ischemia/reperfusion injury (MI/R. However, the endogenous ligand responsible for TLR2 activation has not yet been detected. The objective of this study was to identify HMGB1 as an activator of TLR2 signalling during MI/R. C57BL/6 wild-type (WT or TLR2−/−-mice were injected with vehicle, HMGB1, or HMGB1 BoxA one hour before myocardial ischemia (30 min and reperfusion (24 hrs. Infarct size, cardiac troponin T, leukocyte infiltration, HMGB1 release, TLR4-, TLR9-, and RAGE-expression were quantified. HMGB1 plasma levels were measured in patients undergoing coronary artery bypass graft (CABG surgery. HMGB1 antagonist BoxA reduced cardiomyocyte necrosis during MI/R in WT mice, accompanied by reduced leukocyte infiltration. Injection of HMGB1 did, however, not increase infarct size in WT animals. In TLR2−/−-hearts, neither BoxA nor HMGB1 affected infarct size. No differences in RAGE and TLR9 expression could be detected, while TLR2−/−-mice display increased TLR4 and HMGB1 expression. Plasma levels of HMGB1 were increased MI/R in TLR2−/−-mice after CABG surgery in patients carrying a TLR2 polymorphism (Arg753Gln. We here provide evidence that absence of TLR2 signalling abrogates infarct-sparing effects of HMGB1 blockade.

  4. Evaluation of the Effect of Bosentan-Mediated Endothelin Receptor Blockade on Flap Survival in Rats: An Experimental Study.

    Science.gov (United States)

    Görgülü, Tahsin; Guler, Ramazan; Olgun, Abdulkerim; Torun, Merve; Kargi, Eksal

    2016-08-01

    Local skin flaps are important tools for performing plastic surgery. Skin flaps are used for closure of defects after tumor excision or in tissue losses after trauma. However, problems associated with these flaps are commonly encountered, particularly in areas of marginal necrosis. Bosentan is a vasodilator that exerts its effect through endothelin receptor blockade, and has been shown to prevent ischemic tissue damage. However, no reports have addressed the effect of bosentan on skin flaps. The aim of the study was to investigate the effects of bosentan, which may be applied clinically to promote survival of ischemic skin flaps. A modified McFarlane flap was elevated in the dorsum of 20 Albino Wistar rats with a width-to-length ratio of 3 to 10 cm, respectively, with the caudal base. Perioperatively, 0.9% of physiologic NaCl and injectable distilled water of identical volume were injected into rats in Group 1 (n = 10), and 5 mg/kg bosentan was injected intraperitoneally into rats in Group 2 (n = 10). All of the rats were followed up for 7 days postoperatively. The surviving parts of the flaps were measured at the end of day 7. Acute and chronic inflammation, amount of granulation tissue, fibroblast maturation, amount of collagen, and amounts of reepithelialization and neovascularization present in the ischemic zones of the distal parts of the flaps were evaluated histopathologically, and results were compared statistically. The mean flap survivals were 61.1% in Group 1 and 91.1% in Group 2; the percentage of the surviving flap area in Group 2 was higher than that in Group 1 (p  0.005). Fibroblast maturation, amount of collagen, and amounts of reepithelialization and neovascularization investigated in Group 2 were statistically significantly higher than those in Group 1 (p skin flaps because it decreases ischemic necrosis distal to skin flaps, thus exerting favorable effects on flap survival. PMID:27494588

  5. Central serotonin(2B) receptor blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical dopamine outflow.

    Science.gov (United States)

    Devroye, Céline; Cathala, Adeline; Di Marco, Barbara; Caraci, Filippo; Drago, Filippo; Piazza, Pier Vincenzo; Spampinato, Umberto

    2015-10-01

    The central serotonin2B receptor (5-HT2BR) is currently considered as an interesting pharmacological target for improved treatment of drug addiction. In the present study, we assessed the effect of two selective 5-HT2BR antagonists, RS 127445 and LY 266097, on cocaine-induced hyperlocomotion and dopamine (DA) outflow in the nucleus accumbens (NAc) and the dorsal striatum of freely moving rats. The peripheral administration of RS 127445 (0.16 mg/kg, i.p.) or LY 266097 (0.63 mg/kg, i.p.) significantly reduced basal DA outflow in the NAc shell, but had no effect on cocaine (10 mg/kg, i.p.)-induced DA outflow in this brain region. Also, RS 127445 failed to modify both basal and cocaine-induced DA outflow in the NAc core and the dorsal striatum. Conversely, both 5-HT2BR antagonists reduced cocaine-induced hyperlocomotion. Furthermore, RS 127445 as well as the DA-R antagonist haloperidol (0.1 mg/kg, i.p.) reduced significantly the late-onset hyperlocomotion induced by the DA-R agonist quinpirole (0.5 mg/kg, s.c.). Altogether, these results demonstrate that 5-HT2BR blockade inhibits cocaine-induced hyperlocomotion independently of changes of subcortical DA outflow. This interaction takes place downstream to DA neurons and could involve an action at the level of dorsostriatal and/or NAc DA transmission, in keeping with the importance of these brain regions in the behavioural responses of cocaine. Overall, this study affords additional knowledge into the regulatory control exerted by the 5-HT2BR on ascending DA pathways, and provides additional support to the proposed role of 5-HT2BRs as a new pharmacological target in drug addiction. PMID:26116760

  6. Differential blockade of rat α3β4 and α7 neuronal nicotinic receptors by ω-conotoxin MVIIC, ω-conotoxin GVIA and diltiazem

    Science.gov (United States)

    Herrero, Carlos J; García-Palomero, Esther; Pintado, Antonio J; García, Antonio G; Montiel, Carmen

    1999-01-01

    Rat α3β4 or α7 neuronal nicotinic acetylcholine receptors (AChRs) were expressed in Xenopus laevis oocytes, and the effects of various toxins and non-toxin Ca2+ channel blockers studied. Nicotinic AChR currents were elicited by 1 s pulses of dimethylphenylpiperazinium (DMPP, 100 μM) applied at regular intervals.The N/P/Q-type Ca2+ channel blocker ω-conotoxin MVIIC inhibited α3β4 currents with an IC50 of 1.3 μM; the blockade was non-competitive and reversible. The α7 currents were unaffected.At 1 μM, ω-conotoxin GVIA (N-type Ca2+ channel blocker) inhibited by 24 and 20% α3β4 and α7 currents, respectively. At 1 μM, ω-agatoxin IVA (a P/Q-type Ca2+ channel blocker) did not affect α7 currents and inhibited α3β4 currents by only 15%.L-type Ca2+ channel blockers furnidipine, verapamil and, particularly, diltiazem exhibited a preferential blocking activity on α3β4 nicotinic AChRs.The mechanism of α3β4 currents blockade by ω-conotoxins and diltiazem differed in the following aspects: (i) the onset and reversal of the blockade was faster for toxins; (ii) the blockade by the peptides was voltage-dependent, while that exerted by diltiazem was not; (iii) diltiazem promoted the inactivation of the current while ω-toxins did not.These data show that, at concentrations currently employed as Ca2+ channel blockers, some of these compounds also inhibit certain subtypes of nicotinic AChR currents. Our data calls for caution when interpreting many of the results obtained in neurons and other cell types, where nicotinic receptor and Ca2+ channels coexist. PMID:10455287

  7. Dynamic T-lymphocyte chemokine receptor expression induced by interferon-beta therapy in multiple sclerosis

    DEFF Research Database (Denmark)

    Krakauer, M; Sorensen, P S; Khademi, M;

    2006-01-01

    as these influence central nervous system (CNS) transmigration and inflammation. At 'steady state' (>/=1 day after the most recent IFN-beta injection), IFN-beta treatment increased CD4(+) T-cell surface expression of CC chemokine receptor (CCR)4, CCR5 and CCR7 after 3 months of treatment, whereas that of CXC...... and immunoregulatory genes. In conclusion, IFN-beta treatment caused 'steady-state' increases of several chemokine receptors relevant for CD4(+) T-lymphocyte trafficking and function, possibly facilitating lymphocyte migration into the CNS. An important therapeutic effect of IFN-beta treatment may be the normalization...... of a decreased Th2-related CD4(+) T-cell CCR4 expression in MS patients. Surface chemokine receptor expression and CXCL10 varied according to the timing of blood sampling in relation to the most recent IFN-beta injection. Thus, it is imperative to distinguish acute effects of IFN-beta from steady-state effects....

  8. Dissociated response of thyrotropin and prolactin to dopamine receptor blockade with domperidone in hypothyroid subjects.

    Science.gov (United States)

    Marcondes, J A; Santomauro, A T; Minanni, S L; Wajchenberg, B L

    1991-12-01

    To investigate the hypothesis of an altered hypothalamic dopaminergic activity in primary hypothyroidism, eight patients with hypothyroidism and seven normal subjects, all female, were studied. All of them were submitted to two tests: TRH stimulation and after the administration of dopamine receptor-blocking drug, Domperidone. The hypothyroid patients with basal TSH values less than or equal to 60 mU/L (4 cases--group 1) had lower PRL levels than the remaining 4 subjects with TSH greater than 60 mU/L (group 2) (p less than 0.001), despite all patients presenting the PRL levels within the normal range. A significant increase occurred for both TSH and PRL after the administration of TRH and Domperidone in normal as well as in the hypothyroid subjects, except for TSH in group 1 after the administration of Domperidone. The area under the curve for PRL response to THR was not different between the normal subjects and both hypothyroid groups, while that under the curve for TSH was greater in the hypothyroidism as a whole than in the normal subjects (p = 0.006) and between the hypothyroid groups, being greater in group 2 than in 1 (p less than 0.009). In relation to Domperidone, the area under the curve for TSH was significantly higher in group 2 when compared to the normal controls (p less than 0.001), while for PRL it was not different between hypothyroid groups in relation to normal controls and when groups I and II were compared. These results suggest that the hypothalamic dopamine activity is not altered in primary hypothyroidism and favor the small relevance of dopamine on the control of TSH secretion. PMID:1778595

  9. Partial blockade of nicotinic acetylcholine receptors improves the counterregulatory response to hypoglycemia in recurrently hypoglycemic rats.

    Science.gov (United States)

    LaGamma, Edmund F; Kirtok, Necla; Chan, Owen; Nankova, Bistra B

    2014-10-01

    Recurrent exposure to hypoglycemia can impair the normal counterregulatory hormonal responses that guard against hypoglycemia, leading to hypoglycemia unawareness. This pathological condition known as hypoglycemia-associated autonomic failure (HAAF) is the main adverse consequence that prevents individuals with type 1 diabetes mellitus from attaining the long-term health benefits of tight glycemic control. The underlying molecular mechanisms responsible for the progressive loss of the epinephrine response to subsequent bouts of hypoglycemia, a hallmark sign of HAAF, are largely unknown. Normally, hypoglycemia triggers both the release and biosynthesis of epinephrine through activation of nicotinic acetylcholine receptors (nAChR) on the adrenal glands. We hypothesize that excessive cholinergic stimulation may contribute to impaired counterregulation. Here, we tested whether administration of the nAChR partial agonist cytisine to reduce postganglionic synaptic activity can preserve the counterregulatory hormone responses in an animal model of HAAF. Compared with nicotine, cytisine has limited efficacy to activate nAChRs and stimulate epinephrine release and synthesis. We evaluated adrenal catecholamine production and secretion in nondiabetic rats subjected to two daily episodes of hypoglycemia for 3 days, followed by a hyperinsulinemic hypoglycemic clamp on day 4. Recurrent hypoglycemia decreased epinephrine responses, and this was associated with suppressed TH mRNA induction (a measure of adrenal catecholamine synthetic capacity). Treatment with cytisine improved glucagon responses as well as epinephrine release and production in recurrently hypoglycemic animals. These data suggest that pharmacological manipulation of ganglionic nAChRs may be promising as a translational adjunctive therapy to avoid HAAF in type 1 diabetes mellitus.

  10. Circadian rhythm of heart rate in the rabbit: prolongation of action potential duration by sustained beta adrenoceptor blockade is not due to associated bradycardia.

    Science.gov (United States)

    Vaughan Williams, E M; Dennis, P D; Garnham, C

    1986-07-01

    Six litters of six young rabbits were injected intraperitoneally, two per litter, with saline, alinidine, or nadolol once or twice daily for two weeks. In four litters successful radiotransmissions of electrocardiograms were recorded once hourly for four days before and during treatment. Alinidine and nadolol produced an overall mean bradycardia in comparison with saline treated animals, the effect of alinidine exceeding that of nadolol. At 48-70 hours after the end of treatment the hearts were used for in vitro electrophysiological study. Nadolol, but not alinidine, induced a prolongation of action potential duration compared with that of saline treated littermates in both atrial and ventricular muscle. An incidental observation was that heart rate in the rabbit followed a circadian rhythm, heart rates being slower in the morning and faster in late afternoon and evening. The circadian rhythm was attenuated but not abolished by alinidine and nadolol. These results suggest that if prolongation of action potential duration by sustained beta blockade in patients after myocardial infarction contributes to protection against sudden death (by a class III antiarrhythmic action) then alinidine would not be expected to provide a comparable prophylaxis.

  11. Non-selective beta-adrenergic blockade prevents reduction of the cerebral metabolic ratio during exhaustive exercise in humans

    DEFF Research Database (Denmark)

    Larsen, T.S.; Rasmussen, P.; Overgaard, M.;

    2008-01-01

    .d.) and the arterial-jugular venous (a-v) difference from -0.02 +/- 0.03 mm at rest to 1.0 +/- 0.5 mm (P metabolic ratio decreased from 5.5 +/- 1.4 to 3.0 +/- 0.3 (P ...-v lactate difference (to 0.5 +/- 0.5 mm; P metabolic ratio remained at levels similar to those at rest. Together with the previous finding that the cerebral metabolic ratio is unaffected during exercise with administration of the beta(1......Intense exercise decreases the cerebral metabolic ratio of oxygen to carbohydrates [O(2)/(glucose + (1/2)lactate)], but whether this ratio is influenced by adrenergic stimulation is not known. In eight males, incremental cycle ergometry increased arterial lactate to 15.3 +/- 4.2 mm (mean +/- s...

  12. Appraising the instantaneous secretory rates of luteinizing hormone and testosterone in response to selective mu opiate receptor blockade in late pubertal boys.

    Science.gov (United States)

    Mauras, N; Rogol, A D; Veldhuis, J D

    1987-01-01

    The pulsatile properties of gonadotropin and testosterone release were examined before and after chronic mu opiate receptor blockade with naltrexone, 50 mg every other day, in four normal boys in late puberty (ages 14 8/12 to 15 1/12 years). The nature of spontaneous secretory events was appraised for immunoactive LH and testosterone in blood withdrawn every 20 minutes for 24 hours, using a novel, discrete deconvolution algorithm to estimate apparent instantaneous secretory rates. The application of this methodology revealed that the frequency of discrete LH instantaneous secretory rates increased after mu opiate receptor blockade (P = 0.011). More strikingly, all parameters of testosterone secretory events responded significantly to mu opiate receptor blockade, including increases in mean estimated secretory rate (+47%, P = 0.02), testosterone pulse frequency (+ 64%, P less than 0.001) and amplitude (+ 20%, P = 0.027). Correspondingly, decreases in testosterone interpulse secretory intervals (-35%, P = 0.001), secretory pulse duration (-19%, P = 0.042) and interpulse valley duration (-35%, P = 0.006) also were noted. There was a prominent diurnal rhythm in testosterone secretion with maximal values in the morning and late evening, and marked reductions in the afternoon, sometimes to prepubertal levels. This variation in the testosterone secretory profile paralleled that of LH. In response to naltrexone, the FSH concentration series showed a significant increase in the mean FSH concentration (+ 18%) P = 0.003) and mean peak amplitude (+ 15%, P = 0.002). These data provide indirect evidence of functional coupling of the opiate system with the hypothalamic GnRH pulse generator.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3040654

  13. Evidence for the presence of beta 3-adrenergic receptor mRNA in the human brain.

    Science.gov (United States)

    Rodriguez, M; Carillon, C; Coquerel, A; Le Fur, G; Ferrara, P; Caput, D; Shire, D

    1995-04-01

    The beta 3-adrenergic receptor (AR) is widely distributed in peripheral tissues, but up to now it has not been detected in the central nervous system. By using the polymerase chain reaction (PCR) technique, we found the beta 3-AR mRNA to be present in all the regions of the human brain we investigated. The quantities found were very low compared to those of the beta 1-AR and beta 2-AR mRNAs, being hardly detectable in adult brain. In contrast, the brain of very young infants contained about 100 times more beta 3-AR mRNA than the adult brain, whereas the amounts of beta 1-AR and beta 2-AR transcripts were essentially the same. In addition, using PCR we have cloned a central beta 3-AR coding region from a human frontal cortex cDNA library and have found it to be identical to the corresponding peripheral sequence. PMID:7609625

  14. Estrogen receptor beta is a novel therapeutic target for photoaging.

    Science.gov (United States)

    Chang, Ken C N; Wang, Yihe; Oh, Inn Gyung; Jenkins, Susan; Freedman, Leonard P; Thompson, Catherine C; Chung, Jin Ho; Nagpal, Sunil

    2010-05-01

    One of the many harmful factors faced by the skin is solar UV radiation, which damages skin by inducing chronic low-grade inflammation through increased expression of proinflammatory cytokines, metalloproteinases (MMPs) and cyclooxygenase-2 (COX-2). Estrogen receptors (ERs) alpha and beta are ligand-dependent transcription factors that are expressed in skin, and an ERbeta agonist has previously shown efficacy in vivo in models of pain and inflammation. Because ERbeta does not carry the breast and uterine proliferation liabilities of ERalpha, we decided to explore the possibility of using ERbeta as a target for photoaging. We show that ERbeta-selective compounds suppressed the expression of cytokines and MMPs in activated keratinocytes and fibroblast-based in vitro models of photoaging. Furthermore, in activated dermal fibroblasts, ERbeta-selective compounds also inhibited COX-2. These activities of ERbeta ligands in skin cells correlated with the expression levels of ERbeta and showed reversal by treatment with a potent synthetic ER antagonist. Furthermore, the pharmacology of ERbeta-selective compound was observed in wild-type but not in skin cells obtained from ERbeta knockout mice. Finally, we demonstrate that a synthetic ERbeta agonist inhibited UV-induced photodamage and skin wrinkle formation in a murine model of photoaging. Therefore, the potential of an ERbeta ligand to regulate multiple pathways underlying the cause of photoaging suggests ERbeta to be a novel therapeutic target for the prevention and treatment of photoaging. PMID:20110405

  15. Chronic NMDA receptor blockade in early postnatal period, but not in adulthood, impairs methamphetamine-induced conditioned place preference in rats.

    Science.gov (United States)

    Furuie, Hiroki; Yamada, Kazuo; Ichitani, Yukio

    2016-03-15

    Early postnatal glutamatergic N-methyl-d-aspartate (NMDA) receptor blockade in animals is known to produce various behavioral deficits in adulthood. In the present study rats postnatally (day 7-20) treated chronically with MK-801, an NMDA receptor antagonist, were tested later in adulthood in methamphetamine (MAP)-induced conditioned place preference (CPP) using a unbiased procedure in a three-compartment apparatus. Rats with the same chronic treatment in adulthood were also tested. CPP test consisted of a baseline test before conditioning, place conditioning, and a preference test after conditioning. Rats postnatally treated with MK-801 did not show any evidence of preference for MAP-paired compartment compared with that for unpaired one in the preference test that was shown in rats postnatally treated with saline. On the other hand, rats treated with MK-801 in adulthood were not affected by the treatment and showed significant CPP as was shown in saline-treated control animals. Results suggest the possibility that chronic early postnatal, but not adulthood, NMDA receptor blockade induces persistent deficit of subsequent appetitive classical conditioning.

  16. A systematic review of selective and non-selective beta blockers for prevention of vascular events in patients with acute coronary syndrome or heart failure

    NARCIS (Netherlands)

    O.R. de Peuter; F. Lussana; R.J.G. Peters; H.R. Büller; P.W. Kamphuisen

    2009-01-01

    BACKGROUND: To assess the influence of beta2-receptor suppression on top of selective beta1-receptor blockade on the occurrence of vascular events and on all-cause mortality in patients with acute coronary syndrome (ACS) or heart failure (HF ). METHODS: Systematic review of studies published since 1

  17. Renin angiotensin system blockade reduces urinary levels of soluble urokinase plasminogen activator receptor (suPAR) in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Persson, Frederik; Theilade, Simone; Eugen-Olsen, Jesper;

    2016-01-01

    angiotensin system (RAS) single and dual blockade on suPAR levels in patients with type 2 diabetes and albuminuria. We conducted a post-hoc analysis of a randomized controlled crossover trial. Urine and plasma samples were analyzed for suPAR levels. The placebo period was considered reference and all......Soluble urokinase plasminogen activator receptor (suPAR) is associated with faster decline in kidney function and the pathogenesis of diabetic nephropathy. However, little is known about the impact of treatment on plasma and urinary levels of suPAR. We aimed to investigate the impact of renin...

  18. Magnitude of a conformational change in the glycine receptor beta1-beta2 loop is correlated with agonist efficacy

    DEFF Research Database (Denmark)

    Pless, Stephan Alexander; Lynch, Joseph W

    2009-01-01

    associated with the closed-flip transition in the alpha1-glycine receptor. We employed voltage-clamp fluorometry to compare ligand-binding domain conformational changes induced by the following agonists, listed from highest to lowest affinity and efficacy: glycine > beta-alanine > taurine. Voltage...

  19. Combined renin inhibition/(prorenin receptor blockade in diabetic retinopathy--a study in transgenic (mREN227 rats.

    Directory of Open Access Journals (Sweden)

    Wendy W Batenburg

    Full Text Available Dysfunction of renin-angiotensin system (RAS contributes to the pathogenesis of diabetic retinopathy (DR. Prorenin, the precursor of renin is highly elevated in ocular fluid of diabetic patients with proliferative retinopathy. Prorenin may exert local effects in the eye by binding to the so-called (prorenin receptor ((PRR. Here we investigated the combined effects of the renin inhibitor aliskiren and the putative (PRR blocker handle-region peptide (HRP on diabetic retinopathy in streptozotocin (STZ-induced diabetic transgenic (mRen227 rats (a model with high plasma prorenin levels as well as prorenin stimulated cytokine expression in cultured Müller cells. Adult (mRen227 rats were randomly divided into the following groups: (1 non-diabetic; (2 diabetic treated with vehicle; (3 diabetic treated with aliskiren (10 mg/kg per day; and (4 diabetic treated with aliskiren+HRP (1 mg/kg per day. Age-matched non-diabetic wildtype Sprague-Dawley rats were used as control. Drugs were administered by osmotic minipumps for three weeks. Transgenic (mRen227 rat retinas showed increased apoptotic cell death of both inner retinal neurons and photoreceptors, increased loss of capillaries, as well as increased expression of inflammatory cytokines. These pathological changes were further exacerbated by diabetes. Aliskiren treatment of diabetic (mRen227 rats prevented retinal gliosis, and reduced retinal apoptotic cell death, acellular capillaries and the expression of inflammatory cytokines. HRP on top of aliskiren did not provide additional protection. In cultured Müller cells, prorenin significantly increased the expression levels of IL-1α and TNF-α, and this was completely blocked by aliskiren or HRP, their combination, (PRR siRNA and the AT1R blocker losartan, suggesting that these effects entirely depended on Ang II generation by (PRR-bound prorenin. In conclusion, the lack of effect of HRP on top of aliskiren, and the Ang II-dependency of the ocular

  20. [Characterization of cDNA of T-cell receptor beta chain in rainbow trout].

    Science.gov (United States)

    Partula, S; Fellah, J S; de Guerra, A; Charlemagne, J

    1994-08-01

    Using a two-step PCR strategy, we have cloned several cDNA segments encoding the T-cell receptor beta chain in a Teleost fish, the rainbow trout (Oncorhynchus mykiss). The nine clones analyzed encode identical N-terminal-truncated V beta regions which present limited sequence similarities with several mammalian TcR V beta chains, from residue Tyr-35 to residue Ser-95. These V beta regions are followed by V beta-D beta-J beta-like regions which are different in all the sequenced clones, and by identical C beta regions. The trout C beta domain (156 amino acids) is most related to the chicken and to amphibian (axolotl) C beta domains but no cysteine residue appears in the hinge region. Like in other vertebrate C beta s, the TM region carries a positively charged lysine residue (Lys-271). The intracytoplasmic domain is virtually absent. The possibility to analyze the structure, expression and diversity of a T-cell receptor chain in a Teleost fish model will be important for our future understanding of the evolution of specific immune recognition in vertebrates. PMID:7882160

  1. TGF beta-1 dependent fast stimulation of ATM and p53 phosphorylation following exposure to ionizing radiation does not involve TGF beta-receptor I signalling

    NARCIS (Netherlands)

    Wiegman, Erwin M.; Blaese, Marcet A.; Loeffler, Heidi; Coppes, Rob P.; Rodemann, H. Peter

    2007-01-01

    Background and purpose: It has been proposed that radiation induced stimulation of ATM and downstream components involves activation of TGF beta-1 and that this may be due to TGF beta-1-receptor I-Smad signalling. Therefore, the aim of this study was to clarify the distinct role of TGF beta-1-recept

  2. Cytotoxic T-cells from T-cell receptor transgenic NOD8.3 mice destroy beta-cells via the perforin and Fas pathways.

    Science.gov (United States)

    Dudek, Nadine L; Thomas, Helen E; Mariana, Lina; Sutherland, Robyn M; Allison, Janette; Estella, Eugene; Angstetra, Eveline; Trapani, Joseph A; Santamaria, Pere; Lew, Andrew M; Kay, Thomas W H

    2006-09-01

    Cytotoxic T-cells are the major mediators of beta-cell destruction in type 1 diabetes, but the molecular mechanisms are not definitively established. We have examined the contribution of perforin and Fas ligand to beta-cell destruction using islet-specific CD8(+) T-cells from T-cell receptor transgenic NOD8.3 mice. NOD8.3 T-cells killed Fas-deficient islets in vitro and in vivo. Perforin-deficient NOD8.3 T-cells were able to destroy wild-type but not Fas-deficient islets in vitro. These results imply that NOD8.3 T-cells use both pathways and that Fas is required for beta-cell killing only when perforin is missing. Consistent with this theory, transgenic NOD8.3 mice with beta-cells that do not respond to Fas ligation were not protected from diabetes. We next investigated the mechanism of protection provided by overexpression of suppressor of cytokine signaling-1 (SOCS-1) in beta-cells of NOD8.3 mice. SOCS-1 islets remained intact when grafted into NOD8.3 mice and were less efficiently killed in vitro. However, addition of exogenous peptide rendered SOCS-1 islets susceptible to 8.3 T-cell-mediated lysis. Therefore, NOD8.3 T-cells use both perforin and Fas pathways to kill beta-cells and the surprising blockade of NOD8.3 T-cell-mediated beta-cell death by SOCS-1 overexpression may be due in part to reduced target cell recognition. PMID:16936188

  3. Activation of the Cardiac Renin-Angiotensin System in High Oxygen-Exposed Newborn Rats: Angiotensin Receptor Blockade Prevents the Developmental Programming of Cardiac Dysfunction.

    Science.gov (United States)

    Bertagnolli, Mariane; Dios, Anne; Béland-Bonenfant, Sarah; Gascon, Gabrielle; Sutherland, Megan; Lukaszewski, Marie-Amélie; Cloutier, Anik; Paradis, Pierre; Schiffrin, Ernesto L; Nuyt, Anne Monique

    2016-04-01

    Newborn rats exposed to high oxygen (O2), mimicking preterm birth-related neonatal stress, develop later in life cardiac hypertrophy, dysfunction, fibrosis, and activation of the renin-angiotensin system. Cardiac renin-angiotensin system activation in O2-exposed adult rats is characterized by an imbalance in angiotensin (Ang) receptors type 1/2 (AT1/2), with prevailing AT1 expression. To study the role of renin-angiotensin system in the developmental programming of cardiac dysfunction, we assessed Ang receptor expression during neonatal high O2 exposure and whether AT1 receptor blockade prevents cardiac alterations in early adulthood. Sprague-Dawley newborn rats were kept with their mother in 80% O2 or room air (control) from days 3 to 10 (P3-P10) of life. Losartan or water was administered by gavage from P8 to P10 (n=9/group). Rats were studied at P3 (before O2 exposure), P5, P10 (end of O2), and P28. Losartan treatment had no impact on growth or kidney development. AT1 and Ang type 2 receptors were upregulated in the left ventricle by high O2 exposure (P5 and P10), which was prevented by Losartan treatment at P10. Losartan prevented the cardiac AT1/2 imbalance at P28. Losartan decreased cardiac hypertrophy and fibrosis and improved left ventricle fraction of shortening in P28 O2-exposed rats, which was associated with decreased oxidation of calcium/calmodulin-dependent protein kinase II, inhibition of the transforming growth factor-β/SMAD3 pathway, and upregulation of cardiac angiotensin-converting enzyme 2. In conclusion, short-term Ang II blockade during neonatal high O2 prevents the development of cardiac alterations later in life in rats. These findings highlight the key role of neonatal renin-angiotensin system activation in the developmental programming of cardiac dysfunction induced by deleterious neonatal conditions. PMID:26857347

  4. Activation of the Cardiac Renin-Angiotensin System in High Oxygen-Exposed Newborn Rats: Angiotensin Receptor Blockade Prevents the Developmental Programming of Cardiac Dysfunction.

    Science.gov (United States)

    Bertagnolli, Mariane; Dios, Anne; Béland-Bonenfant, Sarah; Gascon, Gabrielle; Sutherland, Megan; Lukaszewski, Marie-Amélie; Cloutier, Anik; Paradis, Pierre; Schiffrin, Ernesto L; Nuyt, Anne Monique

    2016-04-01

    Newborn rats exposed to high oxygen (O2), mimicking preterm birth-related neonatal stress, develop later in life cardiac hypertrophy, dysfunction, fibrosis, and activation of the renin-angiotensin system. Cardiac renin-angiotensin system activation in O2-exposed adult rats is characterized by an imbalance in angiotensin (Ang) receptors type 1/2 (AT1/2), with prevailing AT1 expression. To study the role of renin-angiotensin system in the developmental programming of cardiac dysfunction, we assessed Ang receptor expression during neonatal high O2 exposure and whether AT1 receptor blockade prevents cardiac alterations in early adulthood. Sprague-Dawley newborn rats were kept with their mother in 80% O2 or room air (control) from days 3 to 10 (P3-P10) of life. Losartan or water was administered by gavage from P8 to P10 (n=9/group). Rats were studied at P3 (before O2 exposure), P5, P10 (end of O2), and P28. Losartan treatment had no impact on growth or kidney development. AT1 and Ang type 2 receptors were upregulated in the left ventricle by high O2 exposure (P5 and P10), which was prevented by Losartan treatment at P10. Losartan prevented the cardiac AT1/2 imbalance at P28. Losartan decreased cardiac hypertrophy and fibrosis and improved left ventricle fraction of shortening in P28 O2-exposed rats, which was associated with decreased oxidation of calcium/calmodulin-dependent protein kinase II, inhibition of the transforming growth factor-β/SMAD3 pathway, and upregulation of cardiac angiotensin-converting enzyme 2. In conclusion, short-term Ang II blockade during neonatal high O2 prevents the development of cardiac alterations later in life in rats. These findings highlight the key role of neonatal renin-angiotensin system activation in the developmental programming of cardiac dysfunction induced by deleterious neonatal conditions.

  5. Dextromethorphan and its metabolite dextrorphan block alpha3beta4 neuronal nicotinic receptors.

    Science.gov (United States)

    Hernandez, S C; Bertolino, M; Xiao, Y; Pringle, K E; Caruso, F S; Kellar, K J

    2000-06-01

    Dextromethorphan (DM), a structural analog of morphine and codeine, has been widely used as a cough suppressant for more than 40 years. DM is not itself a potent analgesic, but it has been reported to enhance analgesia produced by morphine and nonsteroidal anti-inflammatory drugs. Although DM is considered to be nonaddictive, it has been reported to reduce morphine tolerance in rats and to be useful in helping addicted subjects to withdraw from heroin. Here we studied the effects of DM on neuronal nicotinic receptors stably expressed in human embryonic kidney cells. Studies were carried out to examine the effects of DM on nicotine-stimulated whole cell currents and nicotine-stimulated (86)Rb(+) efflux. We found that both DM and its metabolite dextrorphan block nicotinic receptor function in a noncompetitive but reversible manner, suggesting that both drugs block the receptor channel. Consistent with blockade of the receptor channel, neither drug competed for the nicotinic agonist binding sites labeled by [(3)H]epibatidine. Although DM is approximately 9-fold less potent than the widely used noncompetitive nicotinic antagonist mecamylamine in blocking nicotinic receptor function, the block by DM appears to reverse more slowly than that by mecamylamine. These data indicate that DM is a useful antagonist for studying nicotinic receptor function and suggest that it might prove to be a clinically useful neuronal nicotinic receptor antagonist, possibly helpful as an aid for helping people addicted to nicotine to refrain from smoking, as well as in other conditions where blockade of neuronal nicotinic receptors would be helpful. PMID:10869398

  6. Mouse egg integrin alpha 6 beta 1 functions as a sperm receptor.

    Science.gov (United States)

    Almeida, E A; Huovila, A P; Sutherland, A E; Stephens, L E; Calarco, P G; Shaw, L M; Mercurio, A M; Sonnenberg, A; Primakoff, P; Myles, D G; White, J M

    1995-06-30

    Binding between sperm and egg plasma membranes is an essential step in fertilization. Whereas fertilin, a mammalian sperm surface protein, is involved in this crucial interaction, sperm receptors on the egg plasma membrane have not been identified. Because fertilin contains a predicted integrin ligand domain, we investigated the expression and function of integrin subunits in unfertilized mouse eggs. Polymerase chain reactions detected mRNAs for alpha 5, alpha 6, alpha v, beta 1, beta 3, and beta 5. Immunofluorescence revealed alpha 6 beta 1 and alpha v beta 3 on the plasma membrane. GoH3, a function-blocking anti-alpha 6 monoclonal antibody, abolished sperm binding, but a nonfunction-blocking anti-alpha 6 monoclonal antibody, a function-blocking anti-alpha v beta 3 polyclonal antibody, and an RGD peptide had no effect. Somatic cells bound sperm avidly, but only if they expressed alpha 6 beta 1. A peptide analog of the fertilin integrin ligand domain inhibited sperm binding to eggs and alpha 6 beta 1+ cells and diminished GoH3 staining of eggs. Our results indicate a novel role for the integrin alpha 6 beta 1 as a cell-cell adhesion receptor that mediates sperm-egg binding. PMID:7600577

  7. Embryonic GABA(B receptor blockade alters cell migration, adult hypothalamic structure, and anxiety- and depression-like behaviors sex specifically in mice.

    Directory of Open Access Journals (Sweden)

    Matthew S Stratton

    Full Text Available Neurons of the paraventricular nucleus of the hypothalamus (PVN regulate the hypothalamic- pituitary-adrenal (HPA axis and the autonomic nervous system. Females lacking functional GABA(B receptors because of a genetic disruption of the R1 subunit have altered cellular characteristics in and around the PVN at birth. The genetic disruption precluded appropriate assessments of physiology or behavior in adulthood. The current study was conducted to test the long term impact of a temporally restricting pharmacological blockade of the GABA(B receptor to a 7-day critical period (E11-E17 during embryonic development. Experiments tested the role of GABA(B receptor signaling in fetal development of the PVN and later adult capacities for adult stress related behaviors and physiology. In organotypic slices containing fetal PVN, there was a female specific, 52% increase in cell movement speeds with GABA(B receptor antagonist treatment that was consistent with a sex-dependent lateral displacement of cells in vivo following 7 days of fetal exposure to GABA(B receptor antagonist. Anxiety-like and depression-like behaviors, open-field activity, and HPA mediated responses to restraint stress were measured in adult offspring of mothers treated with GABA(B receptor antagonist. Embryonic exposure to GABA(B receptor antagonist resulted in reduced HPA axis activation following restraint stress and reduced depression-like behaviors. There was also increased anxiety-like behavior selectively in females and hyperactivity in males. A sex dependent response to disruptions of GABA(B receptor signaling was identified for PVN formation and key aspects of physiology and behavior. These changes correspond to sex specific prevalence in similar human disorders, namely anxiety disorders and hyperactivity.

  8. Embryonic GABAB Receptor Blockade Alters Cell Migration, Adult Hypothalamic Structure, and Anxiety- and Depression-Like Behaviors Sex Specifically in Mice

    Science.gov (United States)

    Stratton, Matthew S.; Staros, Michelle; Budefeld, Tomaz; Searcy, Brian T.; Nash, Connor; Eitel, Chad; Carbone, David; Handa, Robert J.; Majdic, Gregor; Tobet, Stuart A.

    2014-01-01

    Neurons of the paraventricular nucleus of the hypothalamus (PVN) regulate the hypothalamic- pituitary-adrenal (HPA) axis and the autonomic nervous system. Females lacking functional GABAB receptors because of a genetic disruption of the R1 subunit have altered cellular characteristics in and around the PVN at birth. The genetic disruption precluded appropriate assessments of physiology or behavior in adulthood. The current study was conducted to test the long term impact of a temporally restricting pharmacological blockade of the GABAB receptor to a 7-day critical period (E11–E17) during embryonic development. Experiments tested the role of GABAB receptor signaling in fetal development of the PVN and later adult capacities for adult stress related behaviors and physiology. In organotypic slices containing fetal PVN, there was a female specific, 52% increase in cell movement speeds with GABAB receptor antagonist treatment that was consistent with a sex-dependent lateral displacement of cells in vivo following 7 days of fetal exposure to GABAB receptor antagonist. Anxiety-like and depression-like behaviors, open-field activity, and HPA mediated responses to restraint stress were measured in adult offspring of mothers treated with GABAB receptor antagonist. Embryonic exposure to GABAB receptor antagonist resulted in reduced HPA axis activation following restraint stress and reduced depression-like behaviors. There was also increased anxiety-like behavior selectively in females and hyperactivity in males. A sex dependent response to disruptions of GABAB receptor signaling was identified for PVN formation and key aspects of physiology and behavior. These changes correspond to sex specific prevalence in similar human disorders, namely anxiety disorders and hyperactivity. PMID:25162235

  9. Embryonic GABA(B) receptor blockade alters cell migration, adult hypothalamic structure, and anxiety- and depression-like behaviors sex specifically in mice.

    Science.gov (United States)

    Stratton, Matthew S; Staros, Michelle; Budefeld, Tomaz; Searcy, Brian T; Nash, Connor; Eitel, Chad; Carbone, David; Handa, Robert J; Majdic, Gregor; Tobet, Stuart A

    2014-01-01

    Neurons of the paraventricular nucleus of the hypothalamus (PVN) regulate the hypothalamic- pituitary-adrenal (HPA) axis and the autonomic nervous system. Females lacking functional GABA(B) receptors because of a genetic disruption of the R1 subunit have altered cellular characteristics in and around the PVN at birth. The genetic disruption precluded appropriate assessments of physiology or behavior in adulthood. The current study was conducted to test the long term impact of a temporally restricting pharmacological blockade of the GABA(B) receptor to a 7-day critical period (E11-E17) during embryonic development. Experiments tested the role of GABA(B) receptor signaling in fetal development of the PVN and later adult capacities for adult stress related behaviors and physiology. In organotypic slices containing fetal PVN, there was a female specific, 52% increase in cell movement speeds with GABA(B) receptor antagonist treatment that was consistent with a sex-dependent lateral displacement of cells in vivo following 7 days of fetal exposure to GABA(B) receptor antagonist. Anxiety-like and depression-like behaviors, open-field activity, and HPA mediated responses to restraint stress were measured in adult offspring of mothers treated with GABA(B) receptor antagonist. Embryonic exposure to GABA(B) receptor antagonist resulted in reduced HPA axis activation following restraint stress and reduced depression-like behaviors. There was also increased anxiety-like behavior selectively in females and hyperactivity in males. A sex dependent response to disruptions of GABA(B) receptor signaling was identified for PVN formation and key aspects of physiology and behavior. These changes correspond to sex specific prevalence in similar human disorders, namely anxiety disorders and hyperactivity. PMID:25162235

  10. [Beta-3 adrenergic receptor--structure and role in obesity and metabolic disorders].

    Science.gov (United States)

    Wiejak, J; Wyroba, E

    1999-01-01

    Structure and essential motifs of beta 3-adrenergic receptor (known previously as atypical beta-AR), which plays a central role in regulation of lipid metabolism have been described. Obesity results from an imbalance between caloric intake and energy expenditure. The consequence of catecholamine activation of beta 3-AR is increased mobilization of fatty acids from triglyceride stores (lipolysis) in brown and white adipose tissue as well as increased fatty acid beta-oxidation and heat-production via UCP-1 (thermogenesis) in brown adipose tissue. A pharmacokinetic effects of beta 3-agonists and putative involvement of Trp/Arg mutation in beta 3-AR gene in obesity and another metabolic disorders have been discussed.

  11. Combined chronic blockade of hyper-active L-type calcium channels and NMDA receptors ameliorates HIV-1 associated hyper-excitability of mPFC pyramidal neurons.

    Science.gov (United States)

    Khodr, Christina E; Chen, Lihua; Dave, Sonya; Al-Harthi, Lena; Hu, Xiu-Ti

    2016-10-01

    Human Immunodeficiency Virus type 1 (HIV-1) infection induces neurological and neuropsychological deficits, which are associated with dysregulation of the medial prefrontal cortex (mPFC) and other vulnerable brain regions. We evaluated the impact of HIV infection in the mPFC and the therapeutic potential of targeting over-active voltage-gated L-type Ca(2+) channels (L-channel) and NMDA receptors (NMDAR), as modeled in HIV-1 transgenic (Tg) rats. Whole-cell patch-clamp recording was used to assess the membrane properties and voltage-sensitive Ca(2+) potentials (Ca(2+) influx) in mPFC pyramidal neurons. Neurons from HIV-1 Tg rats displayed reduced rheobase, spike amplitude and inwardly-rectifying K(+) influx, increased numbers of action potentials, and a trend of aberrant firing compared to those from non-Tg control rats. Neuronal hyper-excitation was associated with abnormally-enhanced Ca(2+) influx (independent of NMDAR), which was eliminated by acute L-channel blockade. Combined chronic blockade of over-active L-channels and NMDARs with open-channel blockers abolished HIV effects on spiking, aberrant firing and Ca(2+) potential half-amplitude duration, though not the reduced inward rectification. In contrast, individual chronic blockade of over-active L-channels or NMDARs did not alleviate HIV-induced mPFC hyper-excitability. These studies demonstrate that HIV alters mPFC neuronal activity by dysregulating membrane excitability and Ca(2+) influx through the L-channels. This renders these neurons more susceptible and vulnerable to excitatory stimuli, and could contribute to HIV-associated neuropathogenesis. Combined targeting of over-active L-channels/NMDARs alleviates HIV-induced dysfunction of mPFC pyramidal neurons, emphasizing a potential novel therapeutic strategy that may effectively decrease HIV-induced Ca(2+) dysregulation in the mPFC.

  12. Combined chronic blockade of hyper-active L-type calcium channels and NMDA receptors ameliorates HIV-1 associated hyper-excitability of mPFC pyramidal neurons.

    Science.gov (United States)

    Khodr, Christina E; Chen, Lihua; Dave, Sonya; Al-Harthi, Lena; Hu, Xiu-Ti

    2016-10-01

    Human Immunodeficiency Virus type 1 (HIV-1) infection induces neurological and neuropsychological deficits, which are associated with dysregulation of the medial prefrontal cortex (mPFC) and other vulnerable brain regions. We evaluated the impact of HIV infection in the mPFC and the therapeutic potential of targeting over-active voltage-gated L-type Ca(2+) channels (L-channel) and NMDA receptors (NMDAR), as modeled in HIV-1 transgenic (Tg) rats. Whole-cell patch-clamp recording was used to assess the membrane properties and voltage-sensitive Ca(2+) potentials (Ca(2+) influx) in mPFC pyramidal neurons. Neurons from HIV-1 Tg rats displayed reduced rheobase, spike amplitude and inwardly-rectifying K(+) influx, increased numbers of action potentials, and a trend of aberrant firing compared to those from non-Tg control rats. Neuronal hyper-excitation was associated with abnormally-enhanced Ca(2+) influx (independent of NMDAR), which was eliminated by acute L-channel blockade. Combined chronic blockade of over-active L-channels and NMDARs with open-channel blockers abolished HIV effects on spiking, aberrant firing and Ca(2+) potential half-amplitude duration, though not the reduced inward rectification. In contrast, individual chronic blockade of over-active L-channels or NMDARs did not alleviate HIV-induced mPFC hyper-excitability. These studies demonstrate that HIV alters mPFC neuronal activity by dysregulating membrane excitability and Ca(2+) influx through the L-channels. This renders these neurons more susceptible and vulnerable to excitatory stimuli, and could contribute to HIV-associated neuropathogenesis. Combined targeting of over-active L-channels/NMDARs alleviates HIV-induced dysfunction of mPFC pyramidal neurons, emphasizing a potential novel therapeutic strategy that may effectively decrease HIV-induced Ca(2+) dysregulation in the mPFC. PMID:27326669

  13. Determinants and Changes Associated with Aldosterone Breakthrough after Angiotensin II Receptor Blockade in Patients with Type 2 Diabetes with Overt Nephropathy

    Science.gov (United States)

    Moranne, Olivier; Bakris, George; Fafin, Coraline; Favre, Guillaume; Pradier, Christian

    2013-01-01

    Summary Background and objectives Inhibition of the renin-angiotensin-aldosterone system decreases proteinuria and slows estimated GFR decline in patients with type 2 diabetes mellitus with overt nephropathy. Serum aldosterone levels may increase during renin-angiotensin-aldosterone system blockade. The determinants and consequences of this aldosterone breakthrough remain unknown. Design, setting, participants, & measurements This study examined the incidence, determinants, and changes associated with aldosterone breakthrough in a posthoc analysis of a randomized study that compared the effect of two angiotensin II receptor blockers in patients with type 2 diabetes mellitus with overt nephropathy. Results Of 567 of 860 participants included in this posthoc analysis, 28% of participants developed aldosterone breakthrough, which was defined by an increase greater than 10% over baseline values of serum aldosterone levels after 1 year of angiotensin II receptor blocker treatment. Factors independently associated with aldosterone breakthrough at 1 year were lower serum aldosterone and potassium levels at baseline, higher decreases in sodium intake, systolic BP, and estimated GFR from baseline to 1 year, and use of losartan versus telmisartan. Aldosterone breakthrough at 6 months was not sustained at 1 year in 69% of cases, and it did not predict estimated GFR decrease and proteinuria increase between 6 months and 1 year. Conclusions Aldosterone breakthrough is a frequent event 1 year after initiating renin-angiotensin-aldosterone system blockade, particularly in participants exposed to intensive lowering of BP with sodium depletion and short-acting angiotensin II receptor blockers. Short-term serum aldosterone level increases at 6 months are not associated with negative kidney outcomes between 6 months and 1 year. PMID:23929924

  14. Immunoanalogue of vertebrate beta-adrenergic receptor in the unicellular eukaryote Paramecium.

    Science.gov (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta

    2002-01-01

    Cell fractionation, SDS-PAGE, quantitative Western blot, confocal immunolocalization and immunogold labelling were performed to find an interpretation of the physiological response of the unicellular eukaryote Paramecium to beta-adrenergic ligands. The 69 kDa polypeptide separated by SDS-PAGE in S2 and P2 Paramecium subcellular fractions cross-reacted with antibody directed against human beta2-adrenergic receptor. This was detected by Western blotting followed by chemiluminescent detection. Quantitative image analysis showed that beta-selective adrenergic agonist (-)-isoproterenol--previously shown to enhance phagocytic activity--evoked redistribution of the adrenergic receptor analogue from membraneous (P2) to cytosolic (S2) fraction. The relative increase in immunoreactive band intensity in S2 reached 80% and was paralleled by a 59% decrease in P2 fraction. Confocal immunofluorescence revealed beta2-adrenergic receptor sites on the cell surface and at the ridge of the cytopharynx--where nascent phagosomes are formed. This localization was confirmed by immunoelectron microscopy. These results indicate that the 69 kDa Paramecium polypeptide immunorelated to vertebrate beta2-adrenergic receptor appeared in this evolutionary ancient cell as a nutrient receptor.

  15. Selective pharmacological blockade of the 5-HT7 receptor attenuates light and 8-OH-DPAT induced phase shifts of mouse circadian wheel running activity

    Directory of Open Access Journals (Sweden)

    Jonathan eShelton

    2015-01-01

    Full Text Available Recent reports have illustrated a reciprocal relationship between circadian rhythm disruption and mood disorders. The 5-HT7 receptor may provide a crucial link between the two sides of this equation since the receptor plays a critical role in sleep, depression, and circadian rhythm regulation. To further define the role of the 5-HT7 receptor as a potential pharmacotherapy to correct circadian rhythm disruptions, the current study utilized the selective 5-HT7 antagonist JNJ-18038683 (10 mg/kg in three different circadian paradigms. While JNJ-18038683 was ineffective at phase shifting the onset of wheel running activity in mice when administered at different circadian time (CT points across the circadian cycle, pretreatment with JNJ-18038683 blocked non-photic phase advance (CT6 induced by the 5-HT1A/7 receptor agonist 8-OH-DPAT (3 mg/kg. Since light induced phase shifts in mammals are partially mediated via the modulation of the serotonergic system, we determined if JNJ-18038683 altered phase shifts induced by a light pulse at times known to phase delay (CT15 or advance (CT22 wheel running activity in free running mice. Light exposure resulted in a robust shift in the onset of activity in vehicle treated animals at both times tested. Administration of JNJ-18038683 significantly attenuated the light-induced phase delay and completely blocked the phase advance. The current study demonstrates that pharmacological blockade of the 5-HT7 receptor by JNJ-18038683 blunts both non-photic and photic phase shifts of circadian wheel running activity in mice. These findings highlight the importance of the 5-HT7 receptor in modulating circadian rhythms. Due to the opposite modulating effects of light resetting between diurnal and nocturnal species, pharmacotherapy targeting the 5-HT7 receptor in conjunction with bright light therapy may prove therapeutically beneficial by correcting the desynchronization of internal rhythms observed in depressed individuals.

  16. Blockade of catecholamine-induced growth by adrenergic and dopaminergic receptor antagonists in Escherichia coli O157:H7, Salmonella enterica and Yersinia enterocolitica

    Directory of Open Access Journals (Sweden)

    Lyte Mark

    2007-01-01

    Full Text Available Abstract Background The ability of catecholamines to stimulate bacterial growth was first demonstrated just over a decade ago. Little is still known however, concerning the nature of the putative bacterial adrenergic and/or dopaminergic receptor(s to which catecholamines (norepinephrine, epinephrine and dopamine may bind and exert their effects, or even whether the binding properties of such a receptor are similar between different species. Results Use of specific catecholamine receptor antagonists revealed that only α, and not β, adrenergic antagonists were capable of blocking norepinephrine and epinephrine-induced growth, while antagonism of dopamine-mediated growth was achieved with the use of a dopaminergic antagonist. Both adrenergic and dopaminergic antagonists were highly specific in their mechanism of action, which did not involve blockade of catecholamine-facilitated iron-acquisition. Use of radiolabeled norepinephrine suggested that the adrenergic antagonists could be acting by inhibiting catecholamine uptake. Conclusion The present data demonstrates that the ability of a specific pathogen to respond to a particular hormone is dependent upon the host anatomical region in which the pathogen causes disease as well as the neuroanatomical specificity to which production of the particular hormone is restricted; and that both are anatomically coincidental to each other. As such, the present report suggests that pathogens with a high degree of exclusivity to the gastrointestinal tract have evolved response systems to neuroendocrine hormones such as norepinephrine and dopamine, but not epinephrine, which are found with the enteric nervous system.

  17. Receptor density is key to the alpha2/beta interferon differential activities.

    Science.gov (United States)

    Moraga, Ignacio; Harari, Daniel; Schreiber, Gideon; Uzé, Gilles; Pellegrini, Sandra

    2009-09-01

    Multiple type I interferons (IFN-alpha/beta) elicit Jak/Stat activation, rapid gene induction, and pleiotropic effects, such as differentiation, antiviral protection, and blocks in proliferation, which are dependent on the IFN subtype and the cellular context. To date, ligand- and receptor-specific molecular determinants underlying IFN-alpha/beta differential activities or potencies have been well characterized. To analyze cellular determinants that impact subtype-specific potency, human fibrosarcoma U5A-derived clones, exhibiting a gradient of IFN sensitivity by virtue of increasing receptor levels, were monitored for Jak/Stat signaling, gene induction, cell cycle lengthening, and apoptosis. In cells with scarce receptors, IFN-beta was more potent than IFN-alpha2 in antiproliferative activity, while the two subtypes were equipotent in all other readouts. Conversely, in cells with abundant receptors, IFN-alpha2 matched or even surpassed IFN-beta in all readouts tested. Our results suggest that the differential activities of the IFN subtypes are dictated not only by the intrinsic ligand/receptor binding kinetics but also by the density of cell surface receptor components.

  18. Treg engage lymphotoxin beta receptor for afferent lymphatic transendothelial migration

    Science.gov (United States)

    Brinkman, C. Colin; Iwami, Daiki; Hritzo, Molly K.; Xiong, Yanbao; Ahmad, Sarwat; Simon, Thomas; Hippen, Keli L.; Blazar, Bruce R.; Bromberg, Jonathan S.

    2016-01-01

    Regulatory T cells (Tregs) are essential to suppress unwanted immunity or inflammation. After islet allo-transplant Tregs must migrate from blood to allograft, then via afferent lymphatics to draining LN to protect allografts. Here we show that Tregs but not non-Treg T cells use lymphotoxin (LT) during migration from allograft to draining LN, and that LT deficiency or blockade prevents normal migration and allograft protection. Treg LTαβ rapidly modulates cytoskeletal and membrane structure of lymphatic endothelial cells; dependent on VCAM-1 and non-canonical NFκB signalling via LTβR. These results demonstrate a form of T-cell migration used only by Treg in tissues that serves an important role in their suppressive function and is a unique therapeutic focus for modulating suppression. PMID:27323847

  19. Involvement of tyrosine residues located in the carboxyl tail of the human beta 2-adrenergic receptor in agonist-induced down-regulation of the receptor.

    OpenAIRE

    Valiquette, M; Bonin, H.; Hnatowich, M; Caron, M G; Lefkowitz, R J; Bouvier, M

    1990-01-01

    Chronic exposure of various cell types to adrenergic agonists leads to a decrease in cell surface beta 2-adrenergic receptor (beta 2AR) number. Sequestration of the receptor away from the cell surface as well as a down-regulation of the total number of cellular receptors are believed to contribute to this agonist-mediated regulation of receptor number. However, the molecular mechanisms underlying these phenomena are not well characterized. Recently, tyrosine residues located in the cytoplasmi...

  20. Antagonist of the amylin receptor blocks beta-amyloid toxicity in rat cholinergic basal forebrain neurons.

    Science.gov (United States)

    Jhamandas, Jack H; MacTavish, David

    2004-06-16

    Salvage of cholinergic neurons in the brain through a blockade of the neurotoxic effects of amyloidbeta protein (Abeta) is one of the major, but still elusive, therapeutic goals of current research in Alzheimer's disease (AD). To date, no receptor has been unequivocally identified for Abeta. Human amylin, which acts via a receptor composed of the calcitonin receptor-like receptor and a receptor-associated membrane protein, possesses amyloidogenic properties and has a profile of neurotoxicity that is strikingly similar to Abeta. In this study, using primary cultures of rat cholinergic basal forebrain neurons, we show that acetyl-[Asn30, Tyr32] sCT(8-37) (AC187), an amylin receptor antagonist, blocks Abeta-induced neurotoxicity. Treatment of cultures with AC187 before exposure to Abeta results in significantly improved neuronal survival as judged by MTT and live-dead cell assays. Quantitative measures of Abeta-evoked apoptotic cell death, using Hoechst and phosphotidylserine staining, confirm neuroprotective effects of AC187. We also demonstrate that AC187 attenuates the activation of initiator and effector caspases that mediate Abeta-induced apoptotic cell death. These data are the first to show that expression of Abeta toxicity may occur through the amylin receptor and suggest a novel therapeutic target for the treatment of AD. PMID:15201330

  1. The roles of beta-adrenergic receptors in tumorigenesis and the possible use of beta-adrenergic blockers for cancer treatment: possible genetic and cell-signaling mechanisms

    International Nuclear Information System (INIS)

    Cancer is the leading cause of death in the USA, and the incidence of cancer increases dramatically with age. Beta-adrenergic blockers appear to have a beneficial clinical effect in cancer patients. In this paper, we review the evidence of an association between β-adrenergic blockade and cancer. Genetic studies have provided the opportunity to determine which proteins link β-adrenergic blockade to cancer pathology. In particular, this link involves the major histocompatibility complex class II molecules, the renin–angiotensin system, transcription factor nuclear factor-kappa-light-chain-enhancer of activated B cells, poly(ADP-ribose) polymerase-1, vascular endothelial growth factor, and the reduced form of nicotinamide adenine dinucleotide phosphate oxidase. Beta-adrenergic blockers also exert anticancer effects through non-genomic factors, including matrix metalloproteinase, mitogen-activated protein kinase pathways, prostaglandins, cyclooxygenase-2, oxidative stress, and nitric oxide synthase. In conclusion, β-adrenergic blockade may play a beneficial role in cancer treatment. Additional investigations that examine β-adrenergic blockers as cancer therapeutics are required to further elucidate this role

  2. Defining the role of GLP-1 in the enteroinsulinar axis in type 2 diabetes using DPP-4 inhibition and GLP-1 receptor blockade

    DEFF Research Database (Denmark)

    Aulinger, Benedikt A; Bedorf, Anne; Kutscherauer, Gabriele;

    2014-01-01

    ) inhibition and its glucose-lowering actions were tested after an oral glucose tolerance test (OGTT). The contribution of GLP-1 was examined by infusion of the GLP-1 receptor (GLP-1r) antagonist exendin-9. DPP-4 inhibition reduced glycemia and enhanced insulin levels and the incretin effect (IE). Glucagon was...... suppressed, and gastric emptying (GE) was decelerated. Exendin-9 increased glucose levels and glucagon secretion, attenuated insulinemia and the IE, and accelerated GE. With the GLP-1r antagonist, the glucose-lowering effects of DPP-4 inhibition were reduced by ∼ 50%. However, a significant effect on insulin...... secretion remained during GLP-1r blockade, whereas the inhibitory effects of DPP-4 inhibition on glucagon and GE were abolished. Thus, in this cohort of T2D patients with a substantial IE, GLP-1 contributed ∼ 50% to the insulin excursion after an OGTT with and without DPP-4 inhibition. Thus, a significant...

  3. NMDA receptor blockade alters the intracellular distribution of neuronal nitric oxide synthase in the superficial layers of the rat superior colliculus

    Directory of Open Access Journals (Sweden)

    R.E. de Bittencourt-Navarrete

    2009-02-01

    Full Text Available Nitric oxide (NO is a molecular messenger involved in several events of synaptic plasticity in the central nervous system. Ca2+ influx through the N-methyl-D-aspartate receptor (NMDAR triggers the synthesis of NO by activating the enzyme neuronal nitric oxide synthase (nNOS in postsynaptic densities. Therefore, NMDAR and nNOS are part of the intricate scenario of postsynaptic densities. In the present study, we hypothesized that the intracellular distribution of nNOS in the neurons of superior colliculus (SC superficial layers is an NMDAR activity-dependent process. We used osmotic minipumps to promote chronic blockade of the receptors with the pharmacological agent MK-801 in the SC of 7 adult rats. The effective blockade of NMDAR was assessed by changes in the protein level of the immediate early gene NGFI-A, which is a well-known NMDAR activity-dependent expressing transcription factor. Upon chronic infusion of MK-801, a decrease of 47% in the number of cells expressing NGFI-A was observed in the SC of treated animals. Additionally, the filled dendritic extent by the histochemical product of nicotinamide adenine di-nucleotide phosphate diaphorase was reduced by 45% when compared to the contralateral SC of the same animals and by 64% when compared to the SC of control animals. We conclude that the proper intracellular localization of nNOS in the retinorecipient layers of SC depends on NMDAR activation. These results are consistent with the view that the participation of NO in the physiological and plastic events of the central nervous system might be closely related to an NMDAR activity-dependent function.

  4. Effect of Treatment with Different Doses of 17-Beta-Estradiol on Insulin Receptor Substrate-1

    Directory of Open Access Journals (Sweden)

    González C

    2001-07-01

    Full Text Available CONTEXT: Ovarian hormones modulate insulin sensitivity, but their exact role remains unclear. OBJECTIVE: We tried to determine whether different doses of 17-beta-estradiol cause changes in the regulation of insulin receptor substrate (IRS-1 levels, and if so, the possible implications in insulin sensitivity. DESIGN: Ovariectomized rats were treated with different doses of 17-beta-estradiol at 6, 11 and 16 days. MAIN OUTCOME MEASURES: Immunoprecipitation and Western blotting for IRS-1 were performed in different tissues. RESULTS: We found that estradiol treatment has an influence on the amount of IRS-1 but that it acts in different ways depending on the tissue studied, on the length of treatment, and on the doses employed. CONCLUSIONS: Our results suggest that low concentrations of 17-beta-estradiol could be responsible for the upregulation of insulin receptor substrate 1, increasing insulin sensitivity in muscle and adipose tissue. However, insulin receptor substrate 1 is downregulated with high concentrations of 17-beta-estradiol, thus these high hormone plasma levels could favour insulin resistance in peripheral tissues. The role of 17-beta-estradiol seems to modulate insulin receptor substrate 1 levels in insulin dependent tissues, but in a different manner in each tissue. These novel findings are important for improving knowledge about the possible risk for insulin resistance in women taking oral contraceptives or receiving hormone replacement therapy at menopause.

  5. The pharmacology of spontaneously open alpha 1 beta 3 epsilon GABA A receptor-ionophores.

    Science.gov (United States)

    Maksay, Gábor; Thompson, Sally A; Wafford, Keith A

    2003-06-01

    Human alpha(1)beta(3) epsilon GABA(A) receptors were expressed in Xenopus oocytes and examined using the conventional two-electrode voltage-clamp technique and compared to alpha(1)beta(3)gamma(2) receptors. The effects of several GABA(A) agonists were studied, and the allosteric modulation of the channel by a number of GABAergic modulators investigated. The presence of the epsilon subunit increased the potency and efficacy of direct activation by partial GABA(A) agonists (piperidine-4-sulphonic acid and thio-4-PIOL), pentobarbital and neuro-steroids. Direct activation by 3-hydroxylated neurosteroids was restricted to 3alpha epimers, while chirality at C5 was indifferent. The 3beta-sulfate esters of pregnenolone and dehydroepiandrosterone inhibited the spontaneous currents with efficacies higher, while bicuculline methiodide and SR 95531 did so lower than picrotoxin and TBPS. Furosemide, fipronil, triphenylcyanoborate and Zn(2+) blocked the spontaneous currents of alpha(1)beta(3) epsilon receptors with different efficacies. Flunitrazepam and 4'-chlorodiazepam inhibited the spontaneous currents with micromolar potencies. In conclusion, spontaneously active alpha(1)beta(3) epsilon GABA(A) receptors can be potentiated and blocked by GABAergic agents within a broad range of efficacy.

  6. Dobutamine stress echo is superior to exercise stress testing in achieving target heart rate among patients on beta blockers.

    Science.gov (United States)

    Sabbath, Adam; Pack, Michael; Markiewicz, Richard; John, Jooby; Gaballa, Mohamed; Goldman, Steven; Thai, Hoang

    2005-01-01

    Published guidelines recommend continuing beta-adrenergic receptor blockade in patients undergoing stress testing. We evaluated the role of pharmacological versus exercise stress testing in achieving target heart rate (THR) among patients on beta-adrenergic blockade. We compared data from 140 patients who underwent dobutamine stress echo (DSE) and 143 patients who underwent exercise treadmill testing (ETT). In both groups, beta-adrenergic blocker was continued at the time of stress testing. Overall, patients undergoing DSE achieved THR more frequently than ETT. With beta-adrenergic blockade, DSE patients met THR more frequently than ETT patients (p < 0.001). Without beta-adrenergic blockade, there was no difference between either modality in achieving THR. In both DSE and ETT patients, absence of beta-adrenergic blockade increased the odds of achieving THR [odds ratio (OR): 2.46, p = 0.042 and OR: 7.44, p < 0.001, respectively]. Atropine use with DSE increased the odds of achieving THR (OR: 3.76, p = 0.006). In conclusion, pharmacological stress testing appears to be superior to exercise stress testing in achieving THR among patients on beta-adrenergic blockade.

  7. Discoidin domain receptor 1 is activated independently of beta(1) integrin

    DEFF Research Database (Denmark)

    Vogel, W; Brakebusch, C; Fässler, R;

    2000-01-01

    Various types of collagen have been identified as potential ligands for the two mammalian discoidin domain receptor (DDR) tyrosine kinases, DDR1 and DDR2. It is presently unclear whether collagen-induced DDR receptor activation, which occurs with very slow kinetics, involves additional proteins...... blocking antibodies for alpha(2)beta(1) integrin or in cells with a targeted deletion of the beta(1) integrin gene. Finally, we show that overexpression of dominant negative DDR1 in the myoblast cell line C2C12 blocks cellular differentiation and the formation of myofibers....

  8. Dynamin-association with agonist-mediated sequestration of beta-adrenergic receptor in single-cell eukaryote Paramecium.

    Science.gov (United States)

    Wiejak, Jolanta; Surmacz, Liliana; Wyroba, Elzbieta

    2004-04-01

    Evidence that dynamin is associated with the sequestration of the Paramecium beta(2)-adrenergic receptor (betaAR) immunoanalogue is presented. We previously reported a dramatic change in the distribution of betaAR analogue in the subcellular fractions upon isoproterenol treatment: it is redistributed from the membraneous to the cytosolic fraction, as revealed by quantitative image analysis of western blots. Here we confirm and extend this observation by laser scanning confocal and immunogold electron microscopy. In the presence of isoproterenol (10 micro mol l(-1)) betaAR translocated from the cell surface into dynamin-positive vesicles in the cytoplasmic compartment, as observed by dual fluorochrome immunolabeling in a series of the confocal optical sections. Colocalization of betaAR and dynamin in the tiny endocytic vesicles was detected by further electron microscopic studies. Generally receptor sequestration follows its desensitization, which is initiated by receptor phosphorylation by G-protein-coupled receptor kinase. We cloned and sequenced the gene fragment of 407 nucleotides homologous to the beta-adrenergic receptor kinase (betaARK): its deduced amino acid sequence shows 51.6% homology in 126 amino acids that overlap with the human betaARK2 (GRK3), and may participate in Paramecium betaAR desensitization. These results suggest that the molecular machinery for the desensitization/sequestration of the receptor immunorelated to vertebrate betaAR exists in unicellular PARAMECIUM:

  9. Dynamic expression of alpha 1 beta 1 and alpha 2 beta 1 integrin receptors by human vascular smooth muscle cells. Alpha 2 beta 1 integrin is required for chemotaxis across type I collagen-coated membranes.

    OpenAIRE

    Skinner, M P; Raines, E W; Ross, R.

    1994-01-01

    Vascular smooth muscle cells (SMCs) in the media of normal arteries express alpha 1 beta 1 integrin with no detectable alpha 2 beta 1 as determined by immunocytochemistry. In contrast, immunoprecipitation of integrins expressed by human SMCs cultured from medial explants shows strong expression of alpha 2 beta 1 and no expression of alpha 1 beta 1. The apparent reciprocal expression of these two collagen and laminin receptors was confirmed by flow cytometric analysis of fluorescent labeled ce...

  10. L-653,328: an ocular hypotensive agent with modest beta receptor blocking activity

    Energy Technology Data Exchange (ETDEWEB)

    Sugrue, M.F.; Gautheron, P.; Grove, J.; Mallorga, P.; Viader, M.P.; Baldwin, J.J.; Ponticello, G.S.; Varga, S.L.

    1988-05-01

    L-653,328 is the acetate ester of L-652,698 ((S)-3-tert-butylamino-1-(4-(2(hydroxy)ethyl)phenoxy)2-propanol). The penetration of L-652,698 into the albino rabbit eye was enhanced when the compound was instilled as its prodrug acetate ester. The instillation (one drop of 50 microliter) of 0.01, 0.05 and 0.1% solutions of L-653,328 significantly decreased in a dose-dependent manner the elevated intraocular pressure (IOP) of alpha-chymotrypsinized rabbits by 3.2, 4.7 and 6.1 mm Hg, respectively. A 0.01% solution of L-652,698 failed to significantly lower IOP, whereas this dose of timolol (3.8 mm Hg) and betaxolol (3.3 mm Hg) was effective. L-652,698 was active at 0.05% and 0.1%. Extraocular beta-adrenoceptor blockade was quantified in ganglion-blocked, conscious rabbits by determining effects on heart rate and blood pressure changes to i.v. isoproterenol (0.5 microgram/kg). Doses of timolol blocking isoproterenol-induced hypotension and tachycardia by 50% were 0.0065% and 0.03%, respectively. The corresponding doses for betaxolol were greater than 3% (43% inhibition) and 0.3%. Heart rate and blood pressure changes to isoproterenol were blocked by 18 and 36%, respectively, after the instillation of a 3% solution of L-653,328. The reduced propensity of L-653,328 for extraocular beta-adrenoceptor blockade stems from the modest affinity of L-652,698, its active moiety, for beta-adrenoceptors. The Ki values of L-652,698 for displacement of 125I-iodocyanopindolol binding to beta 1-(left ventricle) and beta 2-binding sites (iris + ciliary body) in the rabbit were 5.7 microM and 7.3 microM, respectively. In marked contrast, the corresponding values for timolol were 12 nM and 1.8 nM.

  11. The Effects of Nucleus Accumbens μ-opioid and Adenosine 2A Receptor Stimulation and Blockade on Instrumental Learning

    OpenAIRE

    Clissold, Kara A.; Pratt, Wayne E.

    2014-01-01

    Prior research has shown that glutamate and dopamine receptors in the nucleus accumbens (NAcc) core are critical for the learning of an instrumental response for food reinforcement. It has also been demonstrated that μ-opioid and adenosine A2A receptors within the NAcc impact feeding and motivational processes. In these experiments, we examined the potential roles of NAcc μ-opioid and A2A receptors on instrumental learning and performance. Sprague-Dawley rats were food restricted and trained ...

  12. Ischemia- and agonist-induced changes in. alpha. - and. beta. -adrenergic receptor traffic in guinea pig hearts

    Energy Technology Data Exchange (ETDEWEB)

    Maisel, A.S.; Motulsky, H.J.; Ziegler, M.G.; Insel, P.A. (Univ. of California, La Jolla (USA))

    1987-11-01

    The authors have used radioligand binding techniques and subcellular fraction to assess whether changes in expression of myocardial {alpha}{sub 1}- and {beta}-adrenergic receptors are mediated by a redistribution of receptors between various membrane fractions. Three fractions were prepared from the left ventricles of guinea pigs that underwent either 1 h of ischemia or injection of epinephrine a crude membrane, a purified sarcolemma, and a light vesicle fraction. In control animals {alpha}{sub 1}-adrenergic receptors (({sup 3}H)prazosin binding) in light vesicles was only 25% of the total {alpha}{sub 1}-receptor density found in sarcolemmal and light vesicle fractions as compared with 50% for {beta}-adrenergic receptors (({sup 125}I)iodocyanopindolol binding sites). Although ischemia was associated with a 53% decrease in the number of light vesicle {beta}-adrenergic receptors and a 42% increase in the number of sarcolemma {beta}-receptors there was no change in the number of light vesicle {alpha}{sub 1}-receptors, even though the number of sarcolemmal {alpha}{sub 1}-receptors increased 34%. Epinephrine treatment promoted internalization of {beta}-adrenergic receptors. These results indicate that {alpha}{sub 1} and {beta}{sub 1}-adrenergic receptors may undergo a different cellular itinerary in guinea pig myocardium. Agonist and ischemia-induced changes in surface {beta}-receptors, but not {alpha}{sub 1}-receptors, appear to result from entry and exit of receptors from an intracellular pool that can be isolated in a light vesicle fraction. Changes in expression of {alpha}{sub 1}-adrenergic receptors may represent changes in the properties of receptors found in the sarcolemma or in a membrane fraction other than the light vesicle fraction that they have isolated.

  13. Cardiac beta-receptors in experimental Chagas' disease Receptores beta cardíacos na doença de Chagas experimental

    Directory of Open Access Journals (Sweden)

    Julio E. Enders

    1995-02-01

    Full Text Available Experimental Chagas' disease (45 to 90 days post-infection showed serious cardiac alterations in the contractility and in the pharmacological response to beta adrenergic receptors in normal and T. cruzi infected mice (post-acute phase. Chagasic infection did not change the beta receptors density (78.591 ± 3.125 fmol/mg protein and 73.647 ± 2.194 fmol/mg protein for controls but their affinity was significantly diminished (Kd = 7.299 ± 0.426 nM and Kd = 3.759 ± 0.212 nM for the control p Estudaram-se os receptores beta cardíacos de camundongos infectados pelo Trypanosoma cruzi na fase pós-aguda da doença de Chagas para estabelecer em que medida os mesmos contribuem a gerar respostas anômalas às catecolaminas observadas nestes miocardios. Utilizara-se 3-H/DHA para a marcação dos receptores beta cardíacos dos camundongos normais e dos infectados na fase pós-aguda (45 a 90 dias pós-infecção. O número dos sítios de fixação foi similar nos dois grupos, 78.591 ± 3.125 fmol/mg. Proteína nos chagásicos e 73.647 ± 2.194 fmol/mg. Proteína no grupo controle. Em vez disso, a afinidade verificou-se significativamente diminuida no grupo chagásico (Kd = 7.299 ± 0.426 nM respeito do controle (Kd = 3.759 ± 0.212 nM p < 0.001. Os resultados obtidos demonstram que as modificações observadas na estimulação adrenérgica do miocárdio chagásico se correlacionam com a menor afinidade dos receptores beta cardíacos e que estas alterações exerceriam uma parte determinante para as consequências funcionais que são detectadas na fase crônica.

  14. Homology modeling of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABA receptor channels and Surflex-docking of fipronil.

    Science.gov (United States)

    Cheng, Jin; Ju, Xiu-Lian; Chen, Xiang-Yang; Liu, Gen-Yan

    2009-09-01

    To further explore the mechanism of selective binding of the representative gamma-aminobutyric acid receptors (GABARs) noncompetitive antagonist (NCA) fipronil to insect over mammalian GABARs, three-dimensional models of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABAR were generated by homology modeling, using the cryo-electron microscopy structure of the nicotinic acetylcholine receptor (nAChR) of Torpedo marmorata as a template. Fipronil was docked into the putative binding site of the human alpha 1 beta 2 gamma 2 and house fly beta 3 receptors by Surflex-docking, and the calculated docking energies are in agreement with experimental results. The GABA receptor antagonist fipronil exhibited higher potency with house fly beta 3 GABAR than with human alpha 1 beta 2 gamma 2 GABAR. Furthermore, analyses of Surflex-docking suggest that the H-bond interaction of fipronil with Ala2 and Thr6 in the second transmembrane segment (TM2) of these GABARs plays a relatively important role in ligand selective binding. The different subunit assemblies of human alpha 1 beta 2 gamma 2 and house fly beta 3 GABARs may result in differential selectivity for fipronil.

  15. Blockade of epidermal growth factor receptors chemosensitizes breast cancer cells through up-regulation of Bnip3L

    NARCIS (Netherlands)

    Real, PJ; Benito, A; Cuevas, J; Berciano, MT; de Juan, A; Coffer, P; Gomez-Roman, J; Lafarga, M; Lopez-Vega, JM; Fernandez-Luna, JL

    2005-01-01

    Epidermal growth factor receptor-1 (EGFR) and EGFR-2 (HER2) have become major targets for cancer treatment. Blocking antibodies and small-molecule inhibitors are being used to silence the activity of these receptors in different tumors with varying efficacy. Thus, a better knowledge on the signaling

  16. Blockade of cannabinoid CB receptor function protects against in vivo disseminating brain damage following NMDA-induced excitotoxicity

    DEFF Research Database (Denmark)

    Hansen, H.H.; Ramos, J.A.; Fernández-Ruiz, J.;

    2002-01-01

    The ability of cannabinoid CB, receptors to influence glutamatergic excitatory neurotransmission has fueled interest in how these receptors and their endogenous ligands may interact in conditions of excitotoxic insults. The present study characterized the impact of stimulated and inhibited CB rec...

  17. Age-associated alterations in hepatic. beta. -adrenergic receptor/adenylate cyclase complex

    Energy Technology Data Exchange (ETDEWEB)

    Graham, S.M.; Herring, P.A.; Arinze, I.J.

    1987-09-01

    The effect of age on catecholamine regulation of hepatic glycogenolysis and on hepatic adenylate cyclase was studied in male rats up to 24 mo of age. Epinephrine and norepinephrine stimulated glycogenolysis in isolated hepatocytes at all age groups studied. Isoproterenol, however, stimulated glycogenolysis only at 24 mo. In isolated liver membranes, usual activators of adenylate cyclase increased the activity of the enzyme considerably more in membranes from 24-mo-old rats than in membranes from either 3- or 22-mo-old rats. The Mn/sup 2 +/-dependent activity of the cyclase was increased by 2.9-fold in 3-mo-old animals and approx. 5.7-fold in 24-mo-old rats, indicating a substantial age-dependent increase in the intrinsic activity of the catalytic unit. The density of the ..beta..-adrenergic receptor, as measured by the binding of (/sup 125/I)-iodocyanopindolol to plasma membranes, was 5-8 fmol/mg protein in rats aged 3-12 mo but increased to 19 fmol/mg protein in 24-mo-old rats. Computer-aided analysis of isoproterenol competition of the binding indicated a small age-dependent increase in the proportion of ..beta..-receptors in the high-affinity state. These observations suggest that ..beta..-receptor-mediated hepatic glycogenolysis in the aged rat is predicated upon increases in the density of ..beta..-receptors as well as increased intrinsic activity of the catalytic unit of adenylate cyclase.

  18. Glucagon-like peptide-1 receptor agonist treatment reduces beta cell mass in normoglycaemic mice

    NARCIS (Netherlands)

    Ellenbroek, J.H.; Tons, H.A.; Westerouen van Meeteren, M.J.; de Graaf, N.; Hanegraaf, M.A.; Rabelink, T.J.; Carlotti, F.; de Koning, E.J.

    2013-01-01

    AIMS/HYPOTHESIS: Incretin-based therapies improve glycaemic control in patients with type 2 diabetes. In animal models of diabetes, glucagon-like peptide-1 receptor agonists (GLP-1RAs) increase beta cell mass. GLP-1RAs are also evaluated in non-diabetic individuals with obesity and cardiovascular di

  19. GPCR engineering yields high-resolution structural insights into beta2-adrenergic receptor function

    DEFF Research Database (Denmark)

    Rosenbaum, Daniel M; Cherezov, Vadim; Hanson, Michael A;

    2007-01-01

    of the reported high-resolution structure of beta2AR-T4L provides insights into inverse-agonist binding and the structural changes required to accommodate catecholamine agonists. Amino acids known to regulate receptor function are linked through packing interactions and a network of hydrogen bonds, suggesting...

  20. Estrogen receptor beta rs1271572 polymorphism and invasive ovarian carcinoma risk

    DEFF Research Database (Denmark)

    Lurie, Galina; Wilkens, Lynne R; Thompson, Pamela J;

    2011-01-01

    The association of ovarian carcinoma risk with the polymorphism rs1271572 in the estrogen receptor beta (ESR2) gene was examined in 4946 women with primary invasive ovarian carcinoma and 6582 controls in a pooled analysis of ten case-control studies within the Ovarian Cancer Association Consortium...

  1. Thyroid Hormone Receptor beta Mediates Acute Illness-Induced Alterations in Central Thyroid Hormone Metabolism

    NARCIS (Netherlands)

    A. Boelen; J. Kwakkel; O. Chassande; E. Fliers

    2009-01-01

    Acute illness in mice profoundly affects thyroid hormone metabolism in the hypothalamus and pituitary gland. It remains unknown whether the thyroid hormone receptor (TR)-beta is involved in these changes. In the present study, we investigated central thyroid hormone metabolism during lipopolysacchar

  2. Fipronil-based photoaffinity probe for Drosophila and human beta 3 GABA receptors.

    Science.gov (United States)

    Sirisoma, N S; Ratra, G S; Tomizawa, M; Casida, J E

    2001-11-19

    Modification of the major insecticide fipronil (1) by replacing three pyrazole substituents (hydrogen for both cyano and amino and trifluoromethyldiazirinyl for trifluoromethylsulfinyl) gives a candidate photoaffinity probe (3) of high potency (IC(50) 2-28 nM) in blocking the chloride channel of Drosophila and human beta 3 GABA receptors.

  3. P2Y12 Receptor Localizes in the Renal Collecting Duct and Its Blockade Augments Arginine Vasopressin Action and Alleviates Nephrogenic Diabetes Insipidus.

    Science.gov (United States)

    Zhang, Yue; Peti-Peterdi, Janos; Müller, Christa E; Carlson, Noel G; Baqi, Younis; Strasburg, David L; Heiney, Kristina M; Villanueva, Karie; Kohan, Donald E; Kishore, Bellamkonda K

    2015-12-01

    P2Y12 receptor (P2Y12-R) signaling is mediated through Gi, ultimately reducing cellular cAMP levels. Because cAMP is a central modulator of arginine vasopressin (AVP)-induced water transport in the renal collecting duct (CD), we hypothesized that if expressed in the CD, P2Y12-R may play a role in renal handling of water in health and in nephrogenic diabetes insipidus. We found P2Y12-R mRNA expression in rat kidney, and immunolocalized its protein and aquaporin-2 (AQP2) in CD principal cells. Administration of clopidogrel bisulfate, an irreversible inhibitor of P2Y12-R, significantly increased urine concentration and AQP2 protein in the kidneys of Sprague-Dawley rats. Notably, clopidogrel did not alter urine concentration in Brattleboro rats that lack AVP. Clopidogrel administration also significantly ameliorated lithium-induced polyuria, improved urine concentrating ability and AQP2 protein abundance, and reversed the lithium-induced increase in free-water excretion, without decreasing blood or kidney tissue lithium levels. Clopidogrel administration also augmented the lithium-induced increase in urinary AVP excretion and suppressed the lithium-induced increase in urinary nitrates/nitrites (nitric oxide production) and 8-isoprostane (oxidative stress). Furthermore, selective blockade of P2Y12-R by the reversible antagonist PSB-0739 in primary cultures of rat inner medullary CD cells potentiated the expression of AQP2 and AQP3 mRNA, and cAMP production induced by dDAVP (desmopressin). In conclusion, pharmacologic blockade of renal P2Y12-R increases urinary concentrating ability by augmenting the effect of AVP on the kidney and ameliorates lithium-induced NDI by potentiating the action of AVP on the CD. This strategy may offer a novel and effective therapy for lithium-induced NDI.

  4. P2Y12 Receptor Localizes in the Renal Collecting Duct and Its Blockade Augments Arginine Vasopressin Action and Alleviates Nephrogenic Diabetes Insipidus.

    Science.gov (United States)

    Zhang, Yue; Peti-Peterdi, Janos; Müller, Christa E; Carlson, Noel G; Baqi, Younis; Strasburg, David L; Heiney, Kristina M; Villanueva, Karie; Kohan, Donald E; Kishore, Bellamkonda K

    2015-12-01

    P2Y12 receptor (P2Y12-R) signaling is mediated through Gi, ultimately reducing cellular cAMP levels. Because cAMP is a central modulator of arginine vasopressin (AVP)-induced water transport in the renal collecting duct (CD), we hypothesized that if expressed in the CD, P2Y12-R may play a role in renal handling of water in health and in nephrogenic diabetes insipidus. We found P2Y12-R mRNA expression in rat kidney, and immunolocalized its protein and aquaporin-2 (AQP2) in CD principal cells. Administration of clopidogrel bisulfate, an irreversible inhibitor of P2Y12-R, significantly increased urine concentration and AQP2 protein in the kidneys of Sprague-Dawley rats. Notably, clopidogrel did not alter urine concentration in Brattleboro rats that lack AVP. Clopidogrel administration also significantly ameliorated lithium-induced polyuria, improved urine concentrating ability and AQP2 protein abundance, and reversed the lithium-induced increase in free-water excretion, without decreasing blood or kidney tissue lithium levels. Clopidogrel administration also augmented the lithium-induced increase in urinary AVP excretion and suppressed the lithium-induced increase in urinary nitrates/nitrites (nitric oxide production) and 8-isoprostane (oxidative stress). Furthermore, selective blockade of P2Y12-R by the reversible antagonist PSB-0739 in primary cultures of rat inner medullary CD cells potentiated the expression of AQP2 and AQP3 mRNA, and cAMP production induced by dDAVP (desmopressin). In conclusion, pharmacologic blockade of renal P2Y12-R increases urinary concentrating ability by augmenting the effect of AVP on the kidney and ameliorates lithium-induced NDI by potentiating the action of AVP on the CD. This strategy may offer a novel and effective therapy for lithium-induced NDI. PMID:25855780

  5. Beta-Adrenergic Receptors and Isoproterenol-stimulated Potassium Transport in Erythrocytes from Normal and Hypothyroid Turkeys: QUANTITATIVE RELATION BETWEEN RECEPTOR OCCUPANCY AND PHYSIOLOGIC RESPONSIVENESS

    OpenAIRE

    Furukawa, Haruyasu; Loeb, John N.; Bilezikian, John P.

    1980-01-01

    We have previously reported that in hypothyroid turkeys the number of beta-adrenergic receptors in intact erythrocytes is reduced by ∼50% without any changes in the affinity of the receptor for the agonist, isoproterenol. In view of the physiological action of the catecholamines to stimulate bidirectional ion fluxes in these cells, we have now examined the possibility that the decrease in beta receptor number might be associated with concomitant changes in catecholamine-dependent potassium io...

  6. Effects of a Proprietary Standardized Orthosiphon stamineus Ethanolic Leaf Extract on Enhancing Memory in Sprague Dawley Rats Possibly via Blockade of Adenosine A2A Receptors

    Directory of Open Access Journals (Sweden)

    Annie George

    2015-01-01

    Full Text Available The aim of the study was to explore a propriety standardized ethanolic extract from leaves of Orthosiphon stamineus Benth in improving impairments in short-term social memory in vivo, possibly via blockade of adenosine A2A receptors (A2AR. The ethanolic extract of O. stamineus leaves showed significant in vitro binding activity of A2AR with 74% inhibition at 150 μg/ml and significant A2AR antagonist activity with 98% inhibition at 300 μg/mL. A significant adenosine A1 receptor (A1R antagonist activity with 100% inhibition was observed at 300 μg/mL. Its effect on learning and memory was assessed via social recognition task using Sprague Dawley rats whereby the ethanolic extract of O. stamineus showed significant (p<0.001 change in recognition index (RI at 300 mg/kg and 600 mg/kg p.o and 120 mg/kg i.p., respectively, compared to the vehicle control. In comparison, the ethanolic extract of Polygonum minus aerial parts showed small change in inflexion; however, it remained insignificant in RI at 200 mg/kg p.o. Our findings suggest that the ethanolic extract of O. stamineus leaves improves memory by reversing age-related deficits in short-term social memory and the possible involvement of adenosine A1 and adenosine A2A as a target bioactivity site in the restoration of memory.

  7. Structure-activity relationships for the irreversible blockade of nicotinic receptor agonist sites by lophotoxin and congeneric diterpene lactones

    Energy Technology Data Exchange (ETDEWEB)

    Culver, P.; Burch, M.; Potenza, C.; Wasserman, L.; Fenical, W.; Taylor, P.

    1985-11-01

    Lophotoxin, a diterpene lactone paralytic toxin from gorgonian corals of the genus Lophogorgia, inhibits ( SVI)-alpha-toxin binding to surface nicotinic receptors of BC3H-1 cells by irreversible occupation of the primary agonist sites. In contrast, receptor-bearing membrane fragments or detergent-solubilized receptors prepared from BC3H-1 cells are not susceptible to lophotoxin block. Thus, lophotoxin inhibition requires intact cells. However, when intact cells were incubated with lophotoxin, subsequent membrane-fragment preparation or detergent solubilization of the receptors did not diminish lophotoxin occupation of ( SVI)-alpha-toxin-binding sites, indicating that lophotoxin binds very tightly to nicotinic receptors. These studies further demonstrate that both surface and nonsurface nicotinic receptors of BC3H-1 cells are susceptible to irreversible occupation by lophotoxin, indicating that the lipophilic toxin freely permeates intact cells. The authors also examined several structural analogs of lophotoxin, one of which was equipotent with lophotoxin for inhibition of ( SVI)-alpha-toxin binding to intact cells and, notably, also blocked alpha-toxin binding to detergent-extracted receptor.

  8. Concanavalin a increases beta-adrenergic and glucocorticoid receptors in porcine splenocytes

    International Nuclear Information System (INIS)

    We identified specific glucocorticoid and beta-adrenergic receptors on porcine splenocytes. There are 2000 to 4000 glucocorticoid receptors per cell with a K /SUB D/ of 2 to 4 nM and 1000 beta-adrenergic receptors with a K /SUB D/ of 0.3 to 0.6 nM. When splenocytes were incubated with concanavalin A (Con A), there was an approximate 2-fold increase in both gluococorticoid and beta-adrenergic receptors with no change in binding affinity. Incubation of splenocytes with cortisol as low as 40 nM (13 ng/ml) inhibited proliferation in response to Con A. This inhibitory effect of cortisol was not due to cytotoxic effects of glucocorticoids. At maximal physiologic concentrations (400 nM; 135 ng/ml), cortisol caused reductions in Con A activation of thymocytes and peripheral blood mononuclear cells. When eight wk old pigs were restrained, there was an increase in plasma cortisol, atrophy of thymus and reduction in skin test responses to phytohemagglutinin. On the basis of the data, we suggest that physiologic concentrations of stress asociated hormones affect functional activities of porcine lymphoid cells. Since activated splenocytes display increased numbers of receptors for these hormones, perhaps glucocorticoids or catecholamines normally function in vivo to suppress clonal expansion of antigen activated and autoreactive T lymphocytes

  9. Repression of estrogen receptor {beta} function by putative tumor suppressor DBC1

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Satoshi [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Wada-Hiraike, Osamu, E-mail: osamuwh-tky@umin.ac.jp [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Nakagawa, Shunsuke; Tanikawa, Michihiro; Hiraike, Haruko; Miyamoto, Yuichiro; Sone, Kenbun; Oda, Katsutoshi [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Fukuhara, Hiroshi [Department of Urology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Nakagawa, Keiichi [Department of Radiology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan); Kato, Shigeaki [SORST, Japan Science and Technology, Honcho 4-1-8, Kawaguchi, Saitama 332-0012 (Japan); Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi 1-1-1 Bunkyo-ku, Tokyo 113-0034 (Japan); Yano, Tetsu; Taketani, Yuji [Department of Obstetrics and Gynecology, Graduate School of Medicine, The University of Tokyo, Hongo 7-3-1 Bunkyo-ku, Tokyo 113-8655 (Japan)

    2010-02-12

    It has been well established that estrogen is involved in the pathophysiology of breast cancer. Estrogen receptor (ER) {alpha} appears to promote the proliferation of cancer tissues, while ER{beta} can protect against the mitogenic effect of estrogen in breast tissue. The expression status of ER{alpha} and ER{beta} may greatly influence on the development, treatment, and prognosis of breast cancer. Previous studies have indicated that the deleted in breast cancer 1 (DBC1/KIAA1967) gene product has roles in regulating functions of nuclear receptors. The gene encoding DBC1 is a candidate for tumor suppressor identified by genetic search for breast cancer. Caspase-dependent processing of DBC1 promotes apoptosis, and depletion of the endogenous DBC1 negatively regulates p53-dependent apoptosis through its specific inhibition of SIRT1. In addition, DBC1 modulates ER{alpha} expression and promotes breast cancer cell survival by binding to ER{alpha}. Here we report an ER{beta}-specific repressive function of DBC1. Immunoprecipitation and immunofluorescence studies show that ER{beta} and DBC1 interact in a ligand-independent manner similar to ER{alpha}. In vitro pull-down assays revealed a direct interaction between DBC1 amino-terminus and activation function-1/2 domain of ER{beta}. Although DBC1 shows no influence on the ligand-dependent transcriptional activation function of ER{alpha}, the expression of DBC1 negatively regulates the ligand-dependent transcriptional activation function of ER{beta}in vivo, and RNA interference-mediated depletion of DBC1 stimulates the transactivation function of ER{beta}. These results implicate the principal role of DBC1 in regulating ER{beta}-dependent gene expressions.

  10. Extracellular quaternary ammonium blockade of transient receptor potential vanilloid subtype 1 channels expressed in Xenopus laevis oocytes

    DEFF Research Database (Denmark)

    Rivera-Acevedo, Ricardo E; Pless, Stephan Alexander; Schwarz, Stephan K W;

    2012-01-01

    Transient receptor potential vanilloid subtype 1 (TRPV1) channels are essential nociceptive integrators in primary afferent neurons. These nonselective cation channels are inhibited by local anesthetic compounds through an undefined mechanism. Here, we show that lidocaine inhibits TRPV1 channels ...

  11. Addition of Angiotensin Receptor Blockade or Mineralocorticoid Antagonism to Maximal Angiotensin-Converting Enzyme Inhibition in Diabetic Nephropathy

    OpenAIRE

    Mehdi, Uzma F.; Adams-Huet, Beverley; Raskin, Philip; Vega, Gloria L.; Toto, Robert D.

    2009-01-01

    Aldosterone promotes glomerular and tubular sclerosis independent of angiotensin II in animal models of diabetic nephropathy. Most human studies testing the renoprotective benefit of adding an angiotensin receptor blocker or a mineralocorticoid receptor antagonist to a regimen based on inhibition of angiotensin-converting enzyme (ACE) used relatively low doses of ACE inhibitors. Furthermore, these studies did not determine whether antiproteinuric effects were independent of BP lowering. We co...

  12. Pharmacological Blockade of Cannabinoid CB1 Receptors in Diet-Induced Obesity Regulates Mitochondrial Dihydrolipoamide Dehydrogenase in Muscle.

    Directory of Open Access Journals (Sweden)

    Sergio Arrabal

    Full Text Available Cannabinoid CB1 receptors peripherally modulate energy metabolism. Here, we investigated the role of CB1 receptors in the expression of glucose/pyruvate/tricarboxylic acid (TCA metabolism in rat abdominal muscle. Dihydrolipoamide dehydrogenase (DLD, a flavoprotein component (E3 of α-ketoacid dehydrogenase complexes with diaphorase activity in mitochondria, was specifically analyzed. After assessing the effectiveness of the CB1 receptor antagonist AM251 (3 mg kg(-1, 14 days on food intake and body weight, we could identified seven key enzymes from either glycolytic pathway or TCA cycle--regulated by both diet and CB1 receptor activity--through comprehensive proteomic approaches involving two-dimensional electrophoresis and MALDI-TOF/LC-ESI trap mass spectrometry. These enzymes were glucose 6-phosphate isomerase (GPI, triosephosphate isomerase (TPI, enolase (Eno3, lactate dehydrogenase (LDHa, glyoxalase-1 (Glo1 and the mitochondrial DLD, whose expressions were modified by AM251 in hypercaloric diet-induced obesity. Specifically, AM251 blocked high-carbohydrate diet (HCD-induced expression of GPI, TPI, Eno3 and LDHa, suggesting a down-regulation of glucose/pyruvate/lactate pathways under glucose availability. AM251 reversed the HCD-inhibited expression of Glo1 and DLD in the muscle, and the DLD and CB1 receptor expression in the mitochondrial fraction. Interestingly, we identified the presence of CB1 receptors at the membrane of striate muscle mitochondria. DLD over-expression was confirmed in muscle of CB1-/- mice. AM251 increased the pyruvate dehydrogenase and glutathione reductase activity in C2C12 myotubes, and the diaphorase/oxidative activity in the mitochondria fraction. These results indicated an up-regulation of methylglyoxal and TCA cycle activity. Findings suggest that CB1 receptors in muscle modulate glucose/pyruvate/lactate pathways and mitochondrial oxidative activity by targeting DLD.

  13. Pharmacological Blockade of Cannabinoid CB1 Receptors in Diet-Induced Obesity Regulates Mitochondrial Dihydrolipoamide Dehydrogenase in Muscle.

    Science.gov (United States)

    Arrabal, Sergio; Lucena, Miguel Angel; Canduela, Miren Josune; Ramos-Uriarte, Almudena; Rivera, Patricia; Serrano, Antonia; Pavón, Francisco Javier; Decara, Juan; Vargas, Antonio; Baixeras, Elena; Martín-Rufián, Mercedes; Márquez, Javier; Fernández-Llébrez, Pedro; De Roos, Baukje; Grandes, Pedro; Rodríguez de Fonseca, Fernando; Suárez, Juan

    2015-01-01

    Cannabinoid CB1 receptors peripherally modulate energy metabolism. Here, we investigated the role of CB1 receptors in the expression of glucose/pyruvate/tricarboxylic acid (TCA) metabolism in rat abdominal muscle. Dihydrolipoamide dehydrogenase (DLD), a flavoprotein component (E3) of α-ketoacid dehydrogenase complexes with diaphorase activity in mitochondria, was specifically analyzed. After assessing the effectiveness of the CB1 receptor antagonist AM251 (3 mg kg(-1), 14 days) on food intake and body weight, we could identified seven key enzymes from either glycolytic pathway or TCA cycle--regulated by both diet and CB1 receptor activity--through comprehensive proteomic approaches involving two-dimensional electrophoresis and MALDI-TOF/LC-ESI trap mass spectrometry. These enzymes were glucose 6-phosphate isomerase (GPI), triosephosphate isomerase (TPI), enolase (Eno3), lactate dehydrogenase (LDHa), glyoxalase-1 (Glo1) and the mitochondrial DLD, whose expressions were modified by AM251 in hypercaloric diet-induced obesity. Specifically, AM251 blocked high-carbohydrate diet (HCD)-induced expression of GPI, TPI, Eno3 and LDHa, suggesting a down-regulation of glucose/pyruvate/lactate pathways under glucose availability. AM251 reversed the HCD-inhibited expression of Glo1 and DLD in the muscle, and the DLD and CB1 receptor expression in the mitochondrial fraction. Interestingly, we identified the presence of CB1 receptors at the membrane of striate muscle mitochondria. DLD over-expression was confirmed in muscle of CB1-/- mice. AM251 increased the pyruvate dehydrogenase and glutathione reductase activity in C2C12 myotubes, and the diaphorase/oxidative activity in the mitochondria fraction. These results indicated an up-regulation of methylglyoxal and TCA cycle activity. Findings suggest that CB1 receptors in muscle modulate glucose/pyruvate/lactate pathways and mitochondrial oxidative activity by targeting DLD.

  14. NMDA and AMPA/kainate glutamatergic receptors in the prelimbic medial prefrontal cortex modulate the elaborated defensive behavior and innate fear-induced antinociception elicited by GABAA receptor blockade in the medial hypothalamus.

    Science.gov (United States)

    de Freitas, Renato Leonardo; Salgado-Rohner, Carlos José; Biagioni, Audrey Francisco; Medeiros, Priscila; Hallak, Jaime Eduardo Cecílio; Crippa, José Alexandre S; Coimbra, Norberto Cysne

    2014-06-01

    The aim of the present study was to investigate the involvement of N-methyl-d-aspartate (NMDA) and amino-3-hydroxy-5-methyl-isoxazole-4-proprionate (AMPA)/kainate receptors of the prelimbic (PL) division of the medial prefrontal cortex (MPFC) on the panic attack-like reactions evoked by γ-aminobutyric acid-A receptor blockade in the medial hypothalamus (MH). Rats were pretreated with NaCl 0.9%, LY235959 (NMDA receptor antagonist), and NBQX (AMPA/kainate receptor antagonist) in the PL at 3 different concentrations. Ten minutes later, the MH was treated with bicuculline, and the defensive responses were recorded for 10 min. The antagonism of NMDA receptors in the PL decreased the frequency and duration of all defensive behaviors evoked by the stimulation of the MH and reduced the innate fear-induced antinociception. However, the pretreatment of the PL cortex with NBQX was able to decrease only part of defensive responses and innate fear-induced antinociception. The present findings suggest that the NMDA-glutamatergic system of the PL is critically involved in panic-like responses and innate fear-induced antinociception and those AMPA/kainate receptors are also recruited during the elaboration of fear-induced antinociception and in panic attack-related response. The activation of the glutamatergic neurotransmission of PL division of the MPFC during the elaboration of oriented behavioral reactions elicited by the chemical stimulation of the MH recruits mainly NMDA receptors in comparison with AMPA/kainate receptors. PMID:23349224

  15. Angiotensin II type 1 receptor blockade partially attenuates hypoxia-induced pulmonary hypertension in newborn piglets: relationship with the nitrergic system

    Energy Technology Data Exchange (ETDEWEB)

    Camelo, J.S. Jr. [Departamento de Puericultura e Pediatria, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Martins, A.R. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Instituto de Ciências Biológicas, Universidade Federal do Triângulo Mineiro, Uberaba, MG (Brazil); Rosa, E. [Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Ramos, S.G. [Departamento de Patologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SPBrasil (Brazil); Hehre, D.; Bancalari, E.; Suguihara, C. [Department of Pediatrics, Division of Neonatology, Neonatal Developmental Biology Laboratory, University of Miami Miller School of Medicine, Miami, FL (United States)

    2012-02-10

    The objective of this study was to observe possible interactions between the renin-angiotensin and nitrergic systems in chronic hypoxia-induced pulmonary hypertension in newborn piglets. Thirteen chronically instrumented newborn piglets (6.3 ± 0.9 days; 2369 ± 491 g) were randomly assigned to receive saline (placebo, P) or the AT{sub 1} receptor (AT{sub 1}-R) blocker L-158,809 (L) during 6 days of hypoxia (FiO{sub 2} = 0.12). During hypoxia, pulmonary arterial pressure (Ppa; P < 0.0001), pulmonary vascular resistance (PVR; P < 0.02) and the pulmonary to systemic vascular resistance ratio (PVR/SVR; P < 0.05) were significantly attenuated in the L (N = 7) group compared to the P group (N = 6). Western blot analysis of lung proteins showed a significant decrease of endothelial NOS (eNOS) in both P and L animals, and of AT{sub 1}-R in P animals during hypoxia compared to normoxic animals (C group, N = 5; P < 0.01 for all groups). AT{sub 1}-R tended to decrease in L animals. Inducible NOS (iNOS) did not differ among P, L, and C animals and iNOS immunohistochemical staining in macrophages was significantly more intense in L than in P animals (P < 0.01). The vascular endothelium showed moderate or strong eNOS and AT{sub 1}-R staining. Macrophages and pneumocytes showed moderate or strong iNOS and AT{sub 1}-R staining, but C animals showed weak iNOS and AT{sub 1}-R staining. Macrophages of L and P animals showed moderate and weak AT{sub 2}-R staining, respectively, but the endothelium of all groups only showed weak staining. In conclusion, pulmonary hypertension induced by chronic hypoxia in newborn piglets is partially attenuated by AT{sub 1}-R blockade. We suggest that AT{sub 1}-R blockade might act through AT{sub 2}-R and/or Mas receptors and the nitrergic system in the lungs of hypoxemic newborn piglets.

  16. Effect of extracellular pH on recombinant alpha1beta2gamma2 and alpha1beta2 GABAA receptors.

    Science.gov (United States)

    Mercik, Katarzyna; Pytel, Maria; Cherubini, Enrico; Mozrzymas, Jerzy W

    2006-08-01

    Recently, we have reported that extracellular protons allosterically modulated neuronal GABA(A) receptors [Mozrzymas, J.W., Zarnowska, E.D., Pytel, M., Mercik, K., 2003a. Modulation of GABA(A) receptors by hydrogen ions reveals synaptic GABA transient and a crucial role of desensitiztion process. Journal of Neuroscience 23, 7981-7992]. However, GABAARs in neurons are heterogeneous and the effect of hydrogen ions depends on the receptor subtype. In particular, gamma2 subunit sets the receptor sensibility to several modulators including protons. However, the mechanisms whereby protons modulate gamma2-containing and gamma2-free GABAARs have not been fully elucidated. To this end, current responses to ultrafast GABA applications were recorded for alpha1beta2gamma2 and alpha1beta2 receptors at different pH values. For both receptor types, increase in pH induced a decrease in amplitudes of currents elicited by saturating [GABA] but this effect was stronger for alpha1beta2 receptors. In the case of alpha1beta2gamma2 receptors, protons strongly affected the current time course due to a down regulation of binding and desensitization rates. This effect was qualitatively similar to that described in neurons. Protons strongly influenced the amplitude of alpha1beta2 receptor-mediated currents but the effect on their kinetics was weak suggesting a predominant direct non-competitive inhibition with a minor allosteric modulation. In conclusion, we provide evidence that extracellular protons strongly affect GABAA receptors and that, depending on the presence of the gamma2 subunit, the modulatory mechanisms show profound quantitative and qualitative differences.

  17. Effects of local alpha2-adrenergic receptor blockade on adipose tissue lipolysis during prolonged systemic adrenaline infusion in normal man

    DEFF Research Database (Denmark)

    Simonsen, Lene; Enevoldsen, Lotte H; Stallknecht, Bente;

    2008-01-01

    During prolonged adrenaline infusion, lipolysis peaks within 30 min and thereafter tends to decline, and we hypothesized that the stimulation of local adipose tissue alpha2-adrenergic receptors accounts for this decline. The lipolytic effect of a prolonged intravenous adrenaline infusion combined....... Regional adipose tissue blood flow was measured by the (133)Xe clearance technique. Regional glycerol output (lipolytic rate) was calculated from these measurements and simultaneous measurements of arterial glycerol concentrations. Adrenaline infusion increased lipolysis in all three depots (data...... circulating adrenaline concentrations, and the decrease in lipolysis in subcutaneous adipose tissue under prolonged adrenaline stimulation is thus not attributed to alpha2-adrenergic receptor inhibition of lipolysis. However, in the preperitoneal adipose tissue depot, alpha2-adrenergic receptor tone plays...

  18. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, J.; Kuriyama, K. (Kyoto Prefectural Univ. of Medicine (Japan))

    1990-05-01

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited (3H)flunitrazepam binding to benzodiazepine receptor, but not (3H)muscimol binding to GABAA receptor as well as t-(3H)butylbicycloorthobenzoate (( 3H) TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively (3H) flunitrazepam binding. On the other hand, the binding of beta-(3H)CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated (3H)muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-(3H)CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for (3H)flunitrazepam, (3H)muscimol and (3H)TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested.

  19. Functional modulation of cerebral gamma-aminobutyric acidA receptor/benzodiazepine receptor/chloride ion channel complex with ethyl beta-carboline-3-carboxylate: Presence of independent binding site for ethyl beta-carboline-3-carboxylate

    International Nuclear Information System (INIS)

    Effect of ethyl beta-carboline-3-carboxylate (beta-CCE) on the function of gamma-aminobutyric acid (GABA)A receptor/benzodiazepine receptor/chloride ion channel complex was studied. Beta-CCE noncompetitively and competitively inhibited [3H]flunitrazepam binding to benzodiazepine receptor, but not [3H]muscimol binding to GABAA receptor as well as t-[3H]butylbicycloorthobenzoate [( 3H] TBOB) binding to chloride ion channel, in particulate fraction of the mouse brain. Ro15-1788 also inhibited competitively [3H] flunitrazepam binding. On the other hand, the binding of beta-[3H]CCE was inhibited noncompetitively and competitively by clonazepam and competitively by Ro15-1788. In agreement with these results, benzodiazepines-stimulated [3H]muscimol binding was antagonized by beta-CCE and Ro15-1788. Gel column chromatography for the solubilized fraction from cerebral particulate fraction by 0.2% sodium deoxycholate (DOC-Na) in the presence of 1 M KCl indicated that beta-[3H]CCE binding site was eluted in the same fraction (molecular weight, 250,000) as the binding sites for [3H]flunitrazepam, [3H]muscimol and [3H]TBOB. GABA-stimulated 36Cl- influx into membrane vesicles prepared from the bovine cerebral cortex was stimulated and attenuated by flunitrazepam and beta-CCE, respectively. These effects of flunitrazepam and beta-CCE on the GABA-stimulated 36Cl- influx were antagonized by Ro15-1788. The present results suggest that the binding site for beta-CCE, which resides on GABAA receptor/benzodiazepine receptor/chloride ion channel complex, may be different from that for benzodiazepine. Possible roles of beta-CCE binding site in the allosteric inhibitions on benzodiazepine binding site as well as on the functional coupling between chloride ion channel and GABAA receptor are also suggested

  20. Post-Retrieval [beta]-Adrenergic Receptor Blockade: Effects on Extinction and Reconsolidation of Cocaine-Cue Memories

    Science.gov (United States)

    Fricks-Gleason, Ashley N.; Marshall, John F.

    2008-01-01

    Contexts and discrete cues associated with drug-taking are often responsible for relapse among addicts. Animal models have shown that interference with the reconsolidation of drug-cue memories can reduce seeking of drugs or drug-paired stimuli. One such model is conditioned place preference (CPP) in which an animal is trained to associate a…

  1. Pharmacological blockade of serotonin 5-HT₇ receptor reverses working memory deficits in rats by normalizing cortical glutamate neurotransmission.

    Directory of Open Access Journals (Sweden)

    Pascal Bonaventure

    Full Text Available The role of 5-HT₇ receptor has been demonstrated in various animal models of mood disorders; however its function in cognition remains largely speculative. This study evaluates the effects of SB-269970, a selective 5-HT₇ antagonist, in a translational model of working memory deficit and investigates whether it modulates cortical glutamate and/or dopamine neurotransmission in rats. The effect of SB-269970 was evaluated in the delayed non-matching to position task alone or in combination with MK-801, a non-competitive NMDA receptor antagonist, and, in separate experiments, with scopolamine, a non-selective muscarinic antagonist. SB-269970 (10 mg/kg significantly reversed the deficits induced by MK-801 (0.1 mg/kg but augmented the deficit induced by scopolamine (0.06 mg/kg. The ability of SB-269970 to modulate MK-801-induced glutamate and dopamine extracellular levels was separately evaluated using biosensor technology and microdialysis in the prefrontal cortex of freely moving rats. SB-269970 normalized MK-801 -induced glutamate but not dopamine extracellular levels in the prefrontal cortex. Rat plasma and brain concentrations of MK-801 were not affected by co-administration of SB-269970, arguing for a pharmacodynamic rather than a pharmacokinetic mechanism. These results indicate that 5-HT₇ receptor antagonists might reverse cognitive deficits associated with NMDA receptor hypofunction by selectively normalizing glutamatergic neurotransmission.

  2. Blockade of the growth hormone (GH) receptor unmasks rapid GH-releasing peptide-6-mediated tissue-specific insulin resistance

    NARCIS (Netherlands)

    A.F. Muller (Alex); L.J. Hofland (Leo); S.W.J. Lamberts (Steven); M. Bidlingmaier; C.J. Strasburger; J.A.M.J.L. Janssen (Joop); A-J. van der Lely (Aart-Jan)

    2001-01-01

    textabstractThe roles of GH and its receptor (GHR) in metabolic control are not yet fully understood. We studied the roles of GH and the GHR using the GHR antagonist pegvisomant for metabolic control of healthy nonobese men in fasting and nonfasting conditions. Ten heal

  3. Hemodynamic effect of angiotensin II receptor blockade in postmenopausal women on a high-sodium diet: A double-blind, randomized, placebo-controlled study

    Science.gov (United States)

    Pechère-Bertschi, Antoinette; Maillard, Marc; Bischof, Paul; Fathi, Marc; Burnier, Michel

    2008-01-01

    Background: Hypertension becomes increasingly prevalent after menopause. Postmenopausal women are more responsive to salt than premenopausal women, and they have been reported to develop marked renal vasoconstriction on a high-sodium diet. Objective: The aim of this study was to assess whether angiotensin II receptor blockade can restore a normal pattern of renal response to salt in postmenopausal women on a high-sodium diet. We also assessed segmental renal sodium handling in that population. Methods: Normotensive and hypertensive postmenopausal women not receiving hormone replacement therapy were enrolled in this prospective, double-blind, placebo-controlled, crossover study. They were assigned to receive irbesartan 150 mg or placebo for 6 weeks; the sequence in which they received irbesartan or placebo was randomized. During the last week of treatment, they received a high-sodium diet (250 mmol/d). Ambulatory blood pressure (ABP), glomerular filtration rate (GFR), and effective renal plasma flow (ERPF) were measured using sinistrin and para-amino-hippurate clearances. Renal sodium handling was assessed by measuring endogenous lithium clearance on day 7 of the high-salt diet. Results: Nineteen women (mean age, 54.7 years; range, 43–72 years; 7 normotensive subjects [mean age, 53.4 years; range, 47–61 years] and 12 hypertensive subjects [mean age, 55.4 years; range, 43–72 years]) were included in the study. When the data for all 19 subjects were pooled, ABP was significantly lower with irbesartan than placebo both during the day (120 [3]/79 [2] vs 127 [3]/85 [2] mm Hg; both, P < 0.01) and at night (systolic BP, 107 [4] vs 111 [4] mm Hg [P < 0.01] and diastolic BP, 71 [2] vs 75 [2] mm Hg [P < 0.05]). Compared with placebo, irbesartan was not associated with a significant change in GFR in either the normotensive or the hypertensive women. When the data for all 19 subjects were pooled, irbesartan was associated with a significant increase in ERPF compared with

  4. Effects of glucagon-like peptide-1 receptor stimulation and blockade on food consumption and body weight in rats treated with a cannabinoid CB1 receptor agonist WIN 55,212-2

    Science.gov (United States)

    Radziszewska, Elżbieta; Bojanowska, Ewa

    2013-01-01

    Background Glucagon-like peptide-1 (GLP-1) and endocannabinoids are involved in appetite control. Recently we have demonstrated that cannabinoid (CB)1 receptor antagonist and GLP-1 receptor agonist synergistically suppress food intake in the rat. The aim of the present study was to determine the effects of GLP-1 receptor stimulation or blockade on feeding behavior in rats treated with WIN 55,212-2, a CB1 receptor agonist. Material/Methods Experiments were performed on adult male Wistar rats. In the first experiment the effects of increasing doses (0.5–4.0 mg/kg) of WIN 55,212-2 injected intraperitoneally on 24-hour food consumption were tested. In further experiments a GLP-1 receptor antagonist, exendin (9-39), and WIN 55,212-2 or a GLP-1 receptor agonist, exendin-4, and WIN 55,212-2 were injected intraperitoneally at subthreshold doses (that alone did not change food intake and body weight) to investigate whether these agents may interact to affect food intake in rats. Results WIN 55,212-2 administered at low doses (0.5–2 mg/kg) did not markedly change 24-hour food consumption; however, at the highest dose, daily food intake was inhibited. Combined administration of WIN 55,212-2 and exendin (9-39) did not change the amount of food consumed compared to either the control group or to each agent injected alone. Combined injection of WIN 55,212-2 and exendin-4 at subthreshold doses resulted in a significant decrease in food intake and body weight in rats. Conclusions Stimulation of the peripheral CB1 receptor by its agonist WIN 55,212-2 can induce anorexigenic effects or potentiate, even at a subthreshold dose, the effects of exendin-4, a known anorectic agent. Hence, this dual action of the cannabinoid system should be considered in the medical use of CB1 agonists. PMID:23291632

  5. Pharmacological blockade of either cannabinoid CB1 or CB2 receptors prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rat

    OpenAIRE

    Blanco-Calvo, Eduardo; Rivera, Patricia; Arrabal, Sergio; Vargas, Antonio; Pavón, Francisco Javier; Serrano, Antonia; Castilla-Ortega, Estela; Galeano, Pablo; Rubio, Leticia; Suárez, Juan; Rodriguez de Fonseca, Fernando

    2014-01-01

    Addiction to major drugs of abuse, such as cocaine, has recently been linked to alterations in adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulates this proliferative response as demonstrated by the finding that pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors not only modulates neurogenesis but also modulates cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alter...

  6. Pharmacological blockade of either, cannabinoid CB1 or CB2 receptors, prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rats.

    OpenAIRE

    EDUARDO eBLANCO-CALVO; PATRICIA eRIVERA; SERGIO eARRABAL; ANTONIO eVARGAS; FRANCISCO JAVIER ePAVON; ANTONIA eSERRANO; PABLO eGALEANO; LETICIA eRUBIO; JUAN eSUAREZ; FERNANDO eRODRIGUEZ DE FONSECA

    2014-01-01

    Addiction to major drugs of abuse such as cocaine has been recently linked to alterations on adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulated this proliferative response since pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors by modulating not only neurogenesis but also cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation . To this...

  7. A role for the androgen metabolite, 5alpha-androstane-3beta,17beta-diol, in modulating oestrogen receptor beta-mediated regulation of hormonal stress reactivity.

    Science.gov (United States)

    Handa, R J; Weiser, M J; Zuloaga, D G

    2009-03-01

    Activation of the hypothalamic-pituitary-adrenal (HPA) axis is a basic response of animals to environmental perturbations that threaten homeostasis. These responses are regulated by neurones in the paraventricular nucleus of the hypothalamus (PVN) that synthesise and secrete corticotrophin-releasing hormone (CRH). Other PVN neuropeptides, such as arginine vasopressin and oxytocin, can also modulate activity of CRH neurones in the PVN and enhance CRH secretagogue activity of the anterior pituitary gland. In rodents, sex differences in HPA reactivity are well established; females exhibit a more robust activation of the HPA axis after stress than do males. These sex differences primarily result from opposing actions of sex steroids, testosterone and oestrogen, on HPA function. Ostreogen enhances stress activated adrenocorticotrophic hormone (ACTH) and corticosterone (CORT) secretion, whereas testosterone decreases the gain of the HPA axis and inhibits ACTH and CORT responses to stress. Data show that androgens can act directly on PVN neurones in the male rat through a novel pathway involving oestrogen receptor (ER)beta, whereas oestrogen acts predominantly through ERalpha. Thus, we examined the hypothesis that, in males, testosterone suppresses HPA function via an androgen metabolite that binds ERbeta. Clues to the neurobiological mechanisms underlying such a novel action can be gleaned from studies showing extensive colocalisation of ERbeta in oxytocin-containing cells of the PVN. Hence, in this review, we address the possibility that testosterone inhibits HPA reactivity by metabolising to 5alpha-androstane-3beta,17beta-diol, a compound that binds ERbeta and regulates oxytocin containing neurones of the PVN. These findings suggest a re-evaluation of studies examining pathways for androgen receptor signalling. PMID:19207807

  8. Ligand-dependent inhibition of beta-catenin/TCF signaling by androgen receptor.

    Science.gov (United States)

    Chesire, Dennis R; Isaacs, William B

    2002-12-01

    Beta-catenin signaling may contribute to prostate cancer (CaP) progression. Although beta-catenin is known to upregulate T cell factor (TCF) target gene expression in CaP cells, recent evidence demonstrates its capacity to enhance ligand-dependent androgen receptor (AR) function. Thus, we wished to further understand the interaction between these two pathways. We find in both CaP cells (CWR22-Rv1, LAPC-4, DU145) and non-CaP cells (HEK-293, TSU, SW480, HCT-116) that beta-catenin/TCF-related transcription (CRT), as measured by activation of a synthetic promoter and that of cyclin D1, is inhibited by androgen treatment. This inhibition is AR-dependent, as it only occurs in cells expressing AR endogenously or transiently, and is abrogated by AR antagonists. Additional analyses convey that the ligand-dependent nature of CRT suppression depends on transactivation-competent AR in the nucleus, but not on indirect effects stemming from AR target gene expression. Given the recent work identifying an AR/beta-catenin interaction, and from our finding that liganded AR does not prompt gross changes in the constitutive nuclear localization of TCF4 or mutant beta-catenin, we hypothesized that transcription factor (i.e. AR and TCF) competition for beta-catenin recruitment may explain, in part, androgen-induced suppression of CRT. To address this idea, we expressed an AR mutant lacking its DNA-binding domain (DBD). This receptor could not orchestrate ligand-dependent CRT repression, thereby providing support for those recent data implicating the AR DBD/LBD as necessary for beta-catenin interaction. Further supporting this hypothesis, TCF/LEF over-expression counteracts androgen-induced suppression of CRT, and requires beta-catenin binding activity to do so. Interestingly, TCF4 over-expression potently antagonizes AR function; however, this inhibition may occur independently of beta-catenin/TCF4 interaction. These results from TCF4 over-expression analyses, taken together, provide

  9. Angiotensin II AT1 receptor blockade decreases vasopressin-induced water reabsorption and AQP2 levels in NaCl-restricted rats

    DEFF Research Database (Denmark)

    Kwon, Tae-Hwan; Nielsen, Jakob; Knepper, M.A.;

    2005-01-01

    Vasopressin and ANG II, which are known to play a major role in renal water and sodium reabsorption, are mainly coupled to the cAMP/PKA and phosphoinositide pathways, respectively. There is evidence for cross talk between these intracellular signaling pathways. We therefore hypothesized that...... vasopressin-induced water reabsorption could be attenuated by ANG II AT1 receptor blockade in rats. To address this, three protocols were used: 1) DDAVP treatment (20 ng/h sc for 7 days, n = 8); 2) DDAVP (20 ng/h sc for 7 days) and candesartan (1 mg·kg−1·day−1 sc for 7 days) cotreatment (n = 8); and 3......) vehicle infusion as the control (n = 8). All rats were maintained on a NaCl-deficient diet (0.1 meq Na+·200 g body wt−1·day−1) during the experiment. DDAVP treatment alone resulted in a significant decrease in urine output (3.1 ± 0.2 ml/day) compared with controls (11.5 ± 2.2 ml/day, P < 0.05), whereas...

  10. Angiotensin II receptor blockade does not protect against progressive loss of residual renal function in hemodialysis patients: A randomized controlled trial (SAFIR study)

    DEFF Research Database (Denmark)

    Kjærgaard, Krista Dybtved; Peters, Christian Daugaard; Jespersen, Bente;

    Background: Glomerular filtration rate (GFR) declines during chronic dialysis treatment. In peritoneal dialysis, blockade of the renin-angiotensin-aldosterone system reduces GFR decline. Observational studies suggest that similar treatment may preserve renal function in hemodialysis (HD). Methods...... centers and randomized to placebo or the angiotensin II receptor blocker irbesartan 300 mg daily. Target systolic blood pressure (BP) was 140 mmHg. Outcomes were GFR measured as the mean of creatinine and urea renal clearance, urine volume and time to anuria. Results: Of the 82 patients randomized...... in both groups and BP did not differ significantly between groups over time. Adverse event rates were similar. GFR declined by 1.7 (1.2 to 2.3) (mean (95% CI)) mL/min/1.73m2/year in the placebo group and by 1.8 (1.1 to 2.4) mL/min/1.73m2/year in the irbesartan-treated group. Mean difference (baseline-12...

  11. NK1 receptor fused to beta-arrestin displays a single-component, high-affinity molecular phenotype

    DEFF Research Database (Denmark)

    Martini, Lene; Hastrup, Hanne; Holst, Birgitte;

    2002-01-01

    with low affinity against antagonists. In contrast, in the NK1-beta-arrestin1 fusion protein, all ligands bound with similar affinity independent of the choice of radioligand and with Hill coefficients near unity. We conclude that the NK1 receptor in complex with arrestin is in a high-affinity, stable......Arrestins are cytosolic proteins that, upon stimulation of seven transmembrane (7TM) receptors, terminate signaling by binding to the receptor, displacing the G protein and targeting the receptor to clathrin-coated pits. Fusion of beta-arrestin1 to the C-terminal end of the neurokinin NK1 receptor...... Gq/G11 and Gs pathways. The NK1-beta-arrestin1 fusion construct bound nonpeptide antagonists with increased affinity but surprisingly also bound two types of agonists, substance P and neurokinin A, with high, normal affinity. In the wild-type NK1 receptor, neurokinin A (NKA) competes for binding...

  12. Dopamine Receptor Blockade Modulates the Rewarding and Aversive Properties of Nicotine via Dissociable Neuronal Activity Patterns in the Nucleus Accumbens

    OpenAIRE

    Sun, Ninglei; Laviolette, Steven R

    2014-01-01

    The mesolimbic pathway comprising the ventral tegmental area (VTA) and projection terminals in the nucleus accumbens (NAc) has been identified as a critical neural system involved in processing both the rewarding and aversive behavioral effects of nicotine. Transmission through dopamine (DA) receptors functionally modulates these effects directly within the NAc. Nevertheless, the neuronal mechanisms within the NAc responsible for these bivalent behavioral effects are presently not known. Usin...

  13. Decreased Incentive Motivation Following Knockout or Acute Blockade of the Serotonin Transporter: Role of the 5-HT2C Receptor.

    Science.gov (United States)

    Browne, Caleb J; Fletcher, Paul J

    2016-09-01

    Acute pharmacological elevation of serotonin (5-hydroxytryptamine; 5-HT) activity decreases operant responding for primary reinforcers, suggesting that 5-HT reduces incentive motivation. The mechanism by which 5-HT alters incentive motivation is unknown, but parallel evidence that 5-HT2C receptor agonists also reduce responding for primary reinforcers implicates this receptor as a potential candidate. These experiments examined whether chronic and acute disruptions of serotonin transporter (SERT) activity altered incentive motivation, and whether the 5-HT2C receptor mediated the effects of elevated 5-HT on behavior. To assess incentive motivation, we measured responding for three different reinforcers: a primary reinforcer (saccharin), a conditioned reinforcer (CRf), and an unconditioned sensory reinforcer (USRf). In the chronic condition, responding was compared between SERT knockout (SERT-KO) mice and their wild-type littermates. In the acute condition, responding was examined in wild-type mice following treatment with 10 or 20 mg/kg citalopram, or its vehicle. The ability of the selective 5-HT2C antagonist SB 242084 to prevent the effects of SERT-KO and citalopram on responding was subsequently examined. Both SERT-KO and citalopram reduced responding for saccharin, a CRf, and a USRf. Treatment with SB 242084 enhanced responding for a CRf and a USRf in SERT-KO mice and blocked the effects of citalopram on CRf and USRf responding. However, SB 242084 was unable to prevent the effects of SERT-KO or citalopram on responding for saccharin. These results support a powerful inhibitory function for 5-HT in the control of incentive motivation, and indicate that the 5-HT2C receptor mediates these effects of 5-HT in a reinforcer-dependent manner. PMID:27125304

  14. Protein-tyrosine-phosphatase SHPTP2 couples platelet-derived growth factor receptor beta to Ras.

    OpenAIRE

    Bennett, A.M.; Tang, T. L.; SUGIMOTO, S; Walsh, C T; Neel, B G

    1994-01-01

    Protein-tyrosine-phosphatase SHPTP2 (Syp/PTP-1D/PTP2C) is the homologue of the Drosophila corkscrew (csw) gene product, which transmits positive signals from receptor tyrosine kinases. Likewise, SHPTP2 has been implicated in positive signaling from platelet-derived growth factor receptor beta (PDGFR). Upon PDGF stimulation, SHPTP2 binds to the PDGFR and becomes tyrosine-phosphorylated. We have identified tyrosine-542 (pY542TNI) as the major in vivo site of SHPTP2 tyrosine phosphorylation. The...

  15. Chemokine receptor expression on B cells and effect of interferon-beta in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Roed, Hanne; Sellebjerg, Finn

    2002-01-01

    We investigated the B-cell expression of chemokine receptors CXCR3, CXCR5 and CCR5 in the blood and cerebrospinal fluid (CSF) from patients in relapse of multiple sclerosis (MS) and in neurological controls. Chemokine receptor expression was also studied in interferon-beta-treated patients...... with relapsing-remitting or secondary progressive MS. We observed significantly higher expression of CXCR3 on B cells in the CSF in active MS than in controls. Patients with active MS also had higher B-cell expression of CCR5 in blood. No major differences between RRMS and SPMS patients were detected...

  16. Glucocorticoid receptor beta increases migration of human bladder cancer cells.

    Science.gov (United States)

    McBeth, Lucien; Nwaneri, Assumpta C; Grabnar, Maria; Demeter, Jonathan; Nestor-Kalinoski, Andrea; Hinds, Terry D

    2016-05-10

    Bladder cancer is observed worldwide having been associated with a host of environmental and lifestyle risk factors. Recent investigations on anti-inflammatory glucocorticoid signaling point to a pathway that may impact bladder cancer. Here we show an inverse effect on the glucocorticoid receptor (GR) isoform signaling that may lead to bladder cancer. We found similar GRα expression levels in the transitional uroepithelial cancer cell lines T24 and UMUC-3. However, the T24 cells showed a significant (p < 0.05) increased expression of GRβ compared to UMUC-3, which also correlated with higher migration rates. Knockdown of GRβ in the T24 cells resulted in a decreased migration rate. Mutational analysis of the 3' untranslated region (UTR) of human GRβ revealed that miR144 might positively regulate expression. Indeed, overexpression of miR144 increased GRβ by 3.8 fold. In addition, miR144 and GRβ were upregulated during migration. We used a peptide nucleic acid conjugated to a cell penetrating-peptide (Sweet-P) to block the binding site for miR144 in the 3'UTR of GRβ. Sweet-P effectively prevented miR144 actions and decreased GRβ expression, as well as the migration of the T24 human bladder cancer cells. Therefore, GRβ may have a significant role in bladder cancer, and possibly serve as a therapeutic target for the disease. PMID:27036026

  17. Ryanodine receptors are involved in nuclear calcium oscillation in primary pancreatic {beta}-cells

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ji [Urological Surgery Research Institute, Southwest Hospital, Third Military Medical University, Chongqing (China); National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Chen, Zheng [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Department of Molecular and Integrative Physiology, University of Michigan, Ann Arbor, MI (United States); Yin, Wenxuan; Miao, Lin [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China); Zhou, Zhansong, E-mail: Zhouzhansong@sohu.com [Urological Surgery Research Institute, Southwest Hospital, Third Military Medical University, Chongqing (China); Ji, Guangju, E-mail: Gj28@ibp.ac.cn [National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing (China)

    2012-06-29

    Highlights: Black-Right-Pointing-Pointer We found that RyRs are expressed on the nuclear envelope in single primary pancreatic {beta}-cells and isolated nuclei. Black-Right-Pointing-Pointer We showed that the pattern of glucose-induced Ca{sup 2+} oscillation in the nucleus and cytosol was similar. Black-Right-Pointing-Pointer Our results demonstrate that ryanodine-sensitive Ca{sup 2+} stores exist and have function in the pancreatic {beta}-cell nucleus. -- Abstract: Ryanodine receptors (RyRs) are mainly located on the endoplasmic reticulum (ER) and play an important role in regulating glucose-induced cytosolic Ca{sup 2+} oscillation in pancreatic {beta}-cells. However, subcellular locations and functions of RyRs on other cell organelles such as nuclear envelope are not well understood. In order to investigate the role of RyRs in nuclear Ca{sup 2+} oscillation we designed and conducted experiments in intact primary pancreatic {beta}-cells. Immunocytochemistry was used to examine the expression of RYRs on the nuclear envelope. Confocal microscopy was used to evaluate the function of RYRs on the nuclear envelope. We found that RyRs are expressed on the nuclear envelope in single primary pancreatic {beta}-cells and isolated nuclei. Laser scanning confocal microscopy studies indicated that application of glucose to the cells co-incubated with Ca{sup 2+} indicator Fluo-4 AM and cell-permeable nuclear indicator Hoechst 33342 resulted in nuclear Ca{sup 2+} oscillation. The pattern of glucose-induced Ca{sup 2+} oscillation in the nucleus and cytosol was similar. The reduction of Ca{sup 2+} oscillation amplitude by ryanodine was much greater in the nucleus though both the cytosol and the nucleus Ca{sup 2+} amplitude decreased by ryanodine. Our results suggest that functional ryanodine receptors not only exist in endoplasmic reticulum but are also expressed in nuclear envelope of pancreatic {beta}-cells.

  18. Beta-2-Adrenergic Receptor Methylation Influences Asthma Phenotype in The School Inner City Asthma Study

    OpenAIRE

    Gaffin, Jonathan M.; Phipatanakul, Wanda

    2014-01-01

    Asthma is the most common chronic illness of childhood and inner city residents suffer a disproportionately high rate of asthma diagnosis and asthma morbidity. The School Inner City Asthma Study investigates the school classroom based environmental exposures that may lead to asthma morbidity in inner city school children with asthma. Within this cohort, we investigated the role of methylation at the promoter region of the beta-2-adrenergic receptor in relation to asthma morbidity. We found th...

  19. Determination of beta-adrenergic receptor blocking pharmaceuticals in united states wastewater effluent

    Energy Technology Data Exchange (ETDEWEB)

    Huggett, D.B.; Khan, I.A.; Foran, C.M.; Schlenk, D

    2003-02-01

    This is the first report of beta-adrenergic receptor antagonist pharmaceuticals in United States wastewater effluent. - Beta adrenergic receptor antagonists ({beta}-Blockers) are frequently prescribed medications in the United States and have been identified in European municipal wastewater effluent, however no studies to date have investigated these compounds in United States wastewater effluent. Municipal wastewater effluent was collected from treatment facilities in Mississippi, Texas, and New York to investigate the occurrence of metoprolol, nadolol, and propranolol. Propranolol was identified in all wastewater samples analyzed (n=34) at concentrations {<=}1.9 {mu}g/l. Metoprolol and nadolol were identified in {>=}71% of the samples with concentrations of metoprolol {<=}1.2 {mu}g/l and nadolol {<=}0.36 {mu}g/l. Time course studies at both Mississippi plants and the Texas plant indicate that concentrations of propranolol, metoprolol, and nadolol remain relatively constant at each sampling period. This study indicates that {beta}-Blockers are present in United States wastewater effluent in the ng/l to {mu}g/l range.

  20. beta. -Receptor-mediated increase in cerebral blood flow during hypoglycemia

    Energy Technology Data Exchange (ETDEWEB)

    Hollinger, B.R.; Bryan, R.M. (Pennsylvania State Univ., Hershey (USA))

    1987-10-01

    The authors tested the hypothesis that {beta}-adrenergic receptor stimulation is involved with the increase in regional cerebral blood flow (rCBF) during hypoglycemia. Rats were surgically prepared with the use of halothane-nitrous oxide anesthesia. A plaster restraining cast was placed around the hindquarters, and anesthesia was discontinued. Hypoglycemia was produced by an intravenous injection of insulin; normoglycemic control rates were given saline. Propranolol was administered to some control and some hypoglycemic rats to block the {beta}-adrenergic receptors. Regional CBF was measured using 4-(N-methyl-{sup 14}C)iodoantipyrine. Regional CBF increased during hypoglycemia in rats that were not treated with propranolol. The increase varied from {approximately}60 to 200% depending on the brain region. During hypoglycemia, propranolol abolished the increase in rCBF in the hypothalamus, cerebellum, and pyramidal tract. In other regions the increase in rCBF was only 33-65% of the increase in hypoglycemic rats that were not treated with propranolol. They conclude that {beta}-receptor stimulation plays a major role in the increase in rCBF during hypoglycemia.

  1. Blockade of the growth hormone (GH) receptor unmasks rapid GH-releasing peptide-6-mediated tissue-specific insulin resistance

    OpenAIRE

    Muller, Alex; Hofland, Leo; Lamberts, Steven; Bidlingmaier, M.; Strasburger, C. J.; Janssen, Joop; van der Lely, Aart-Jan

    2001-01-01

    textabstractThe roles of GH and its receptor (GHR) in metabolic control are not yet fully understood. We studied the roles of GH and the GHR using the GHR antagonist pegvisomant for metabolic control of healthy nonobese men in fasting and nonfasting conditions. Ten healthy subjects were enrolled in a double blind, placebo-controlled study on the effects of pegvisomant on GHRH and GH-releasing peptide-6 (GHRP-6)-induced GH secretion before and after 3 days of fasting and under nonfasting condi...

  2. Pharmacological blockade of either, cannabinoid CB1 or CB2 receptors, prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rats.

    Directory of Open Access Journals (Sweden)

    EDUARDO eBLANCO-CALVO

    2014-01-01

    Full Text Available Addiction to major drugs of abuse such as cocaine has been recently linked to alterations on adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulated this proliferative response since pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors by modulating not only neurogenesis but also cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation . To this end we examined if pharmacological blockade of either CB1 (Rimonabant, 3 mg/kg or CB2 receptors (AM630, 3 mg/kg affects cell proliferation (labeled with BrdU, found in the subventricular zone (SVZ of the lateral ventricles and the dentate subgranular zone (SGZ. In addition, we measured cell apoptosis (monitored by the expression of cleaved caspase-3 and glial activation ( by analizing the expression of GFAP and Iba-1 in the striatum and hippocampus, during acute or repeated (4 days cocaine administration (20 mg/kg. Results showed that acute cocaine decreased the number of BrdU+ cells in SVZ and SGZ. In contrast, repeated cocaine reduced the number of BrdU+ cells in SVZ only. Both acute and repeated cocaine increased the number of cleaved caspase-3+, GFAP+ and Iba1+ cells in the hippocampus, an effect counteracted by AM630 or Rimonabant that increased the number of BrdU+, GFAP+ and Iba1+ cells in the hippocampus. These results indicate that changes on neurogenic, apoptotic and gliosis processes, which were produced as a consequence of repeated cocaine administration, were normalized by the pharmacological blockade of CB1 and CB2. The restoring effects of cannabinoid receptor blockade on hippocampal cell proliferation were associated with a prevention of the induction of conditioned locomotion, but not of cocaine-induced sensitization.

  3. PCP-induced alterations in cerebral glucose utilization in rat brain: blockade by metaphit, a PCP-receptor-acylating agent

    Energy Technology Data Exchange (ETDEWEB)

    Tamminga, C.A.; Tanimoto, K.; Kuo, S.; Chase, T.N.; Contreras, P.C.; Rice, K.C.; Jackson, A.E.; O' Donohue, T.L.

    1987-01-01

    The effects of phencyclidine (PCP) on regional cerebral glucose utilization was determined by using quantitative autoradiography with (/sup 14/C)-2-deoxyglucose. PCP increased brain metabolism in selected areas of cortex, particularly limbic, and in the basal ganglia and thalamus, whereas the drug decreased metabolism in areas related to audition. These results are consistent with the known physiology of central PCP neurons and may help to suggest brain areas involved in PCP-mediated actions. Moreover, based on the behavioral similarities between PCP psychosis and an acute schizophrenic episode, these data may be relevant to the understanding of schizophrenia. The PCP-receptor-acylating agent, metaphit, blocked most of these PCP actions. In addition, metaphit by itself was found to diminish glucose utilization rather uniformly throughout brain. These results indicate an antagonist effect of metaphit on the PCP system and suggest a widespread action of metaphit, putatively at a PCP-related site, possibly in connection with the N-methyl-D-aspartate (NMDA) receptor.

  4. In situ detection of TGF betas, TGF beta receptor Ⅱ mRNA and telomerase activity in rat cholangiocarcinogenesis

    Institute of Scientific and Technical Information of China (English)

    Jian-Ping Lu; Jian-Qun Mao; Ming-Sheng Li; Shi-Lun Lu; Xi-Qi Hu; Shi-Neng Zhu; Shintaro Nomura

    2003-01-01

    AIM: Initial report on the in situ examination of the mRNA expression of transforming growth factor betas (TGFβs),TGFβ type Ⅱ receptor (TβRII) and telomerase activity in the experimental rat liver tissue during cholangiocarcinogenesis.METHODS: Rat liver cholangiocarcinogenesis was induced by 3'-methyl 4-dimethylazobenzene (3'Me-DAB). In situhybridization was used to examine the TGFβs) and TGFβ type Ⅱ receptor (TβRⅡ) mRNA, in situ TRAP was used to check the telomerase activity in the tissue samples.RESULTS: There was no TGFβs, TβRⅡ mRNA expression or telomerase activity in the control rat cholangiocytes. The expression of TGFβ1, TβRⅡ was increased in regenerative,hyperplastic, dysplastic cholangiocytes and cholangiocarcinoma (CC) cells. The expression of TGFβ2 mRNA was observed in only a part of hyperplastic, dysplastic cholangiocytes. TGFβ3expression was very weak, only in hyperplastic lesion. There was positive telomerase activity in the regenerative,hyperplastic, dysplastic cholangiocytes, and CC cells. Stroma fibroblasts of these lesions also showed positive TGFβs, TβRⅡ mRNA expression and telomerase activity.CONCLUSION: There were TGFβs, TβRⅡ expression and telomerase activity in hyperplastic, dysplastic cholangiocytes,cholangiocarcinoma cells as well as in stroma fibroblasts during cholangiocarcinogenesis. Their expression or activity is important in cholangiocarcinogenesis andstroma formation.

  5. Effect of perioperative beta blockade in patients with diabetes undergoing major non-cardiac surgery: randomised placebo controlled, blinded multicentre trial

    DEFF Research Database (Denmark)

    Juul, Anne Benedicte; Wetterslev, Jørn; Gluud, Christian;

    2006-01-01

    Objectives To evaluate the long term effects of perioperative blockade on mortality and cardiac morbidity in patients with diabetes undergoing major non-cardiac surgery. Design Randomised placebo controlled and blinded multicentre trial. Analyses were by intention to treat. Setting University...... anaesthesia and surgical centres and one coordinating centre. Participants 921 patients aged > 39 scheduled for major non-cardiac surgery. Interventions 100 mg metoprolol controlled and extended release or placebo administered from the day before surgery to a maximum of eight perioperative days. Main outcome...... with serious adverse events was 2.4% (- 0.8% to 5.6%). Conclusions Perioperative metoprolol did not significantly affect mortality and cardiac morbidity in these patients with diabetes. Confidence intervals, however, were wide, and the issue needs reassessment. Trial registration Current Controlled Trials...

  6. Human-Specific SNP in Obesity Genes, Adrenergic Receptor Beta2 (ADRB2), Beta3 (ADRB3), and PPAR γ2 (PPARG), during Primate Evolution

    OpenAIRE

    Takenaka, Akiko; Nakamura, Shin; Mitsunaga, Fusako; Inoue-Murayama, Miho; Udono, Toshifumi; Suryobroto, Bambang

    2012-01-01

    Adrenergic-receptor beta2 (ADRB2) and beta3 (ADRB3) are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM) in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG) is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and ...

  7. Histamine-1 receptor blockade does not prevent nitroglycerin induced migraine. Support for the NO-hypothesis of migraine

    DEFF Research Database (Denmark)

    Lassen, L H; Thomsen, L L; Kruuse, C;

    1996-01-01

    It has previously been shown that in migraine sufferers infusion of glyceryl trinitrate (GTN) and histamine causes an immediate headache during the infusion and a genuine migraine attack one to several hours after the infusion. This identical time profile indicates a common mechanism of action....... To evaluate whether GTN causes headache via liberation of histamine, we studied the effect of GTN 0.5 micrograms.kg-1.min-1 for 20 min in seven migraine sufferers, once after pretreatment with the histamine-1 (H1)-receptor blocker mepyramine (0.5 mg.kg-1) and once without pretreatment. This mepyramine dose...... with transcranial Doppler, were also unaffected by the mepyramine pretreatment. Our results demonstrate that neither headache nor arterial dilatation due to GTN infusion is caused by histamine release. In all likelihood the common mediator of migraine induction by GTN and histamine is nitric oxide....

  8. Involvement of prelimbic medial prefrontal cortex in panic-like elaborated defensive behaviour and innate fear-induced antinociception elicited by GABAA receptor blockade in the dorsomedial and ventromedial hypothalamic nuclei: role of the endocannabinoid CB1 receptor.

    Science.gov (United States)

    Freitas, Renato Leonardo de; Salgado-Rohner, Carlos José; Hallak, Jaime Eduardo Cecílio; Crippa, José Alexandre de Souza; Coimbra, Norberto Cysne

    2013-09-01

    It has been shown that GABAA receptor blockade in the dorsomedial and ventromedial hypothalamic nuclei (DMH and VMH, respectively) induces elaborated defensive behavioural responses accompanied by antinociception, which has been utilized as an experimental model of panic attack. Furthermore, the prelimbic (PL) division of the medial prefrontal cortex (MPFC) has been related to emotional reactions and the processing of nociceptive information. The aim of the present study was to investigate the possible involvement of the PL cortex and the participation of local cannabinoid CB1 receptors in the elaboration of panic-like reactions and in innate fear-induced antinociception. Elaborated fear-induced responses were analysed during a 10-min period in an open-field test arena. Microinjection of the GABAA receptor antagonist bicuculline into the DMH/VMH evoked panic-like behaviour and fear-induced antinociception, which was decreased by microinjection of the non-selective synaptic contact blocker cobalt chloride in the PL cortex. Moreover, microinjection of AM251 (25, 100 or 400 pmol), an endocannabinoid CB1 receptor antagonist, into the PL cortex also attenuated the defensive behavioural responses and the antinociception that follows innate fear behaviour elaborated by DMH/VMH. These data suggest that the PL cortex plays an important role in the organization of elaborated forward escape behaviour and that this cortical area is also involved in the elaboration of innate fear-induced antinociception. Additionally, CB1 receptors in the PL cortex modulate both panic-like behaviours and fear-induced antinociception elicited by disinhibition of the DMH/VMH through microinjection of bicuculline. PMID:23521775

  9. Contrasting effects of lithium chloride and CB1 receptor blockade on enduring changes in the valuation of reward.

    Directory of Open Access Journals (Sweden)

    Giovanni eHernandez

    2011-09-01

    Full Text Available When an organism has been trained to respond for a reward, its learned behavior can be characterized as goal-directed or habitual based on whether or not it is susceptible to reward devaluation. Here, we evaluated whether instrumental responding for brain stimulation reward (BSR can devalued using a paradigm traditionally used for natural rewards. Rats were trained to lever press for BSR. Subsequently, BSR was paired with either lithium chloride (LiCl, 5 mg/kg, i.p, a pro-emetic, or AM251, a CB1 receptor antagonist (3 mg/kg, i.p.. Pairings of BSR with these two compounds or their respective vehicle were performed in a novel environment so that only unconditional effects of BSR were affected by the pharmacological manipulations. Subsequently, in a probe test, all rats were returned in the drug-free state to the boxes where they had received training instrumental responding was reassessed in the absence of BSR delivery. LiCl produced enduring decreases in the number of responses during the test session, whereas AM251 had no effect. These results show that instrumental responding for BSR is susceptible to devaluation, in accord with the proposal that this behavior is supported at least in part by associations between the response and the rewarding outcome. Furthermore, they suggest that the reward modulation observed in studies involving the use of CB1 receptor antagonists arises from changes in the organism’s motivation rather than due to drug-induced changes in the intrinsic value of reward.

  10. Lifelong disturbance of serotonin transporter functioning results in fear learning deficits: Reversal by blockade of CRF1 receptors.

    Science.gov (United States)

    Bijlsma, Elisabeth Y; Hendriksen, Hendrikus; Baas, Johanna M P; Millan, Mark J; Groenink, Lucianne

    2015-10-01

    The inability to associate aversive events with relevant cues (i.e. fear learning) may lead to maladaptive anxiety. To further study the role of the serotonin transporter (SERT) in fear learning, classical fear conditioning was studied in SERT knockout rats (SERT(-/-)) using fear potentiation of the startle reflex. Next, fear acquisition and concomitant development of contextual conditioned fear were monitored during training. To differentiate between developmental and direct effects of reduced SERT functioning, effects of acute and chronic SSRI treatment were studied in adult rats. Considering the known interactions between serotonin and corticotropin-releasing factor (CRF), we studied the effect of the CRFR1 antagonist CP154,526 on behavioral changes observed and determined CRF1 receptor levels in SERT(-/-) rats. SERT(-/-) showed blunted fear potentiation and enhanced contextual fear, which resulted from a deficit in fear acquisition. Paroxetine treatment did not affect acquisition or expression of fear-potentiated startle, suggesting that disturbed fear learning in SERT(-/-) results from developmental changes and not from reduced SERT functioning. Although CRF1 receptor levels did not differ significantly between genotypes, CP154,526 treatment normalized both cue- and contextual fear in SERT(-/-) during acquisition, but not expression of fear-potentiated startle. The disrupted fear acquisition and concomitant increase in contextual conditioned fear-potentiated startle fear in SERT(-/-) resembles the associative learning deficit seen in patients with panic disorder and suggests that normal SERT functioning is crucial for the development of an adequate fear neuro-circuitry. Moreover, the normalization of fear acquisition by CP154,526 suggests a role for central CRF signaling in the generalization of fear.

  11. Food restriction prevents an age-associated increase in rat liver beta-adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Dax, E.M.; Ingram, D.K.; Partilla, J.S.; Gregerman, R.I.

    1989-05-01

    In male Wistar rats fed ad libitum (24% protein, 4.5 Kcal/gm), the (/sup 125/I)iodopindolol binding capacity of the beta-adrenergic receptors in liver of 24-month-old animals is 3-4 times greater than that of 6-month-old counterparts. In rats fed the same diet, on alternate days from weaning, the receptor capacity did not increase significantly between 6 and 24 months (10.20 +/- 0.55 vs 9.20 +/- 0.72 fmol/mg) or between 24 and 30 months. This was not due to acute dietary deprivation, as rats food-restricted for only 2 weeks, at 23.5 months of age, also showed elevated receptor capacities compared to 6-month-old ad libitum fed animals. Moreover, intermittent feeding produced no significant effects among 6-month-old animals, whether restricted since weaning or for two weeks prior to sacrifice. Many biochemical parameters that decrease with aging in rats fed ad libitum are prevented by dietary restriction. Our results demonstrate that a reproducible biochemical process that increases with aging is also prevented with dietary restriction. The age-related, liver beta-receptor increase may be a potentially reliable marker for studying biochemical perturbations that modify life span.

  12. Food restriction prevents an age-associated increase in rat liver beta-adrenergic receptors

    International Nuclear Information System (INIS)

    In male Wistar rats fed ad libitum (24% protein, 4.5 Kcal/gm), the [125I]iodopindolol binding capacity of the beta-adrenergic receptors in liver of 24-month-old animals is 3-4 times greater than that of 6-month-old counterparts. In rats fed the same diet, on alternate days from weaning, the receptor capacity did not increase significantly between 6 and 24 months (10.20 +/- 0.55 vs 9.20 +/- 0.72 fmol/mg) or between 24 and 30 months. This was not due to acute dietary deprivation, as rats food-restricted for only 2 weeks, at 23.5 months of age, also showed elevated receptor capacities compared to 6-month-old ad libitum fed animals. Moreover, intermittent feeding produced no significant effects among 6-month-old animals, whether restricted since weaning or for two weeks prior to sacrifice. Many biochemical parameters that decrease with aging in rats fed ad libitum are prevented by dietary restriction. Our results demonstrate that a reproducible biochemical process that increases with aging is also prevented with dietary restriction. The age-related, liver beta-receptor increase may be a potentially reliable marker for studying biochemical perturbations that modify life span

  13. Nanoscale organization of {beta}{sub 2}-adrenergic receptor-Venus fusion protein domains on the surface of mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Vobornik, Dusan; Rouleau, Yanouchka; Haley, Jennifer [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Bani-Yaghoub, Mahmud [Institute for Biological Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Taylor, Rod [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Johnston, Linda J., E-mail: Linda.Johnston@nrc-cnrc.gc.ca [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada); Pezacki, John Paul, E-mail: John.Pezacki@nrc-cnrc.gc.ca [Steacie Institute for Molecular Sciences, National Research Council Canada, Ottawa, ON, Canada K1A 0R6 (Canada)

    2009-04-24

    Adrenergic receptors are a key component of nanoscale multiprotein complexes that are responsible for controlling the beat rate in a mammalian heart. We demonstrate the ability of near-field scanning optical microscopy (NSOM) to visualize {beta}{sub 2}-adrenergic receptors ({beta}{sub 2}AR) fused to the GFP analogue Venus at the nanoscale on HEK293 cells. The expression of the {beta}{sub 2}AR-Venus fusion protein was tightly controlled using a tetracycline-induced promoter. Both the size and density of the observed nanoscale domains are dependent on the level of induction and thus the level of protein expression. At concentrations between 100 and 700 ng/ml of inducer doxycycline, the size of domains containing the {beta}{sub 2}AR-Venus fusion protein appears to remain roughly constant, but the number of domains per cell increase. At 700 ng/ml doxycycline the functional receptors are organized into domains with an average diameter of 150 nm with a density similar to that observed for the native protein on primary murine cells. By contrast, larger micron-sized domains of {beta}{sub 2}AR are observed in the membrane of the HEK293 cells that stably overexpress {beta}{sub 2}AR-GFP and {beta}{sub 2}AR-eYFP. We conclude that precise chemical control of gene expression is highly advantageous for the use {beta}{sub 2}AR-Venus fusion proteins as models for {beta}{sub 2}AR function. These observations are critical for designing future cell models and assays based on {beta}{sub 2}AR, since the receptor biology is consistent with a relatively low density of nanoscale receptor domains.

  14. Signaling through urokinase and urokinase receptor in lung cancer cells requires interactions with beta1 integrins.

    Science.gov (United States)

    Tang, Chi-Hui; Hill, Marla L; Brumwell, Alexis N; Chapman, Harold A; Wei, Ying

    2008-11-15

    The urokinase receptor (uPAR) is upregulated upon tumor cell invasion and correlates with poor lung cancer survival. Although a cis-interaction with integrins has been ascribed to uPAR, whether this interaction alone is critical to urokinase (uPA)- and uPAR-dependent signaling and tumor promotion is unclear. Here we report the functional consequences of point mutations of uPAR (H249A-D262A) that eliminate beta1 integrin interactions but maintain uPA binding, vitronectin attachment and association with alphaV integrins, caveolin and epidermal growth factor receptor. Disruption of uPAR interactions with beta1 integrins recapitulated previously reported findings with beta1-integrin-derived peptides that attenuated matrix-dependent ERK activation, MMP expression and in vitro migration by human lung adenocarcinoma cell lines. The uPAR mutant cells acquired enhanced capacity to adhere to vitronectin via uPAR-alphaVbeta5-integrin, rather than through the uPAR-alpha3beta1-integrin complex and they were unable to initiate uPA signaling to activate ERK, Akt or Stat1. In an orthotopic lung cancer model, uPAR mutant cells exhibited reduced tumor size compared with cells expressing wild-type uPAR. Taken together, the results indicate that uPAR-beta1-integrin interactions are essential to signals induced by integrin matrix ligands or uPA that support lung cancer cell invasion in vitro and progression in vivo. PMID:18940913

  15. Signal processing in the TGF-beta superfamily ligand-receptor network.

    Directory of Open Access Journals (Sweden)

    Jose M G Vilar

    2006-01-01

    Full Text Available The TGF-beta pathway plays a central role in tissue homeostasis and morphogenesis. It transduces a variety of extracellular signals into intracellular transcriptional responses that control a plethora of cellular processes, including cell growth, apoptosis, and differentiation. We use computational modeling to show that coupling of signaling with receptor trafficking results in a highly versatile signal-processing unit, able to sense by itself absolute levels of ligand, temporal changes in ligand concentration, and ratios of multiple ligands. This coupling controls whether the response of the receptor module is transient or permanent and whether or not different signaling channels behave independently of each other. Our computational approach unifies seemingly disparate experimental observations and suggests specific changes in receptor trafficking patterns that can lead to phenotypes that favor tumor progression.

  16. TGF-{beta} receptors, in a Smad-independent manner, are required for terminal skeletal muscle differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Droguett, Rebeca; Cabello-Verrugio, Claudio; Santander, Cristian [Centro de Regulacion Celular y Patologia, Centro de Regeneracion y Envejecimiento (CARE), Departamento de Biologia Celular y Molecular, MIFAB, Pontificia Universidad Catolica de Chile, Santiago (Chile); Brandan, Enrique, E-mail: ebrandan@bio.puc.cl [Centro de Regulacion Celular y Patologia, Centro de Regeneracion y Envejecimiento (CARE), Departamento de Biologia Celular y Molecular, MIFAB, Pontificia Universidad Catolica de Chile, Santiago (Chile)

    2010-09-10

    Skeletal muscle differentiation is strongly inhibited by transforming growth factor type {beta} (TGF-{beta}), although muscle formation as well as regeneration normally occurs in an environment rich in this growth factor. In this study, we evaluated the role of intracellular regulatory Smads proteins as well as TGF-{beta}-receptors (TGF-{beta}-Rs) during skeletal muscle differentiation. We found a decrease of TGF-{beta} signaling during differentiation. This phenomenon is explained by a decline in the levels of the regulatory proteins Smad-2, -3, and -4, a decrease in the phosphorylation of Smad-2 and lost of nuclear translocation of Smad-3 and -4 in response to TGF-{beta}. No change in the levels and inhibitory function of Smad-7 was observed. In contrast, we found that TGF-{beta}-R type I (TGF-{beta}-RI) and type II (TGF-{beta}-RII) increased on the cell surface during skeletal muscle differentiation. To analyze the direct role of the serine/threonine kinase activities of TGF-{beta}-Rs, we used the specific inhibitor SB 431542 and the dominant-negative form of TGF-{beta}-RII lacking the cytoplasmic domain. The TGF-{beta}-Rs were important for successful muscle formation, determined by the induction of myogenin, creatine kinase activity, and myosin. Silencing of Smad-2/3 expression by specific siRNA treatments accelerated myogenin, myosin expression, and myotube formation; although when SB 431542 was present inhibition in myosin induction and myotube formation was observed, suggesting that these last steps of skeletal muscle differentiation require active TGF-{beta}-Rs. These results suggest that both down-regulation of Smad regulatory proteins and cell signaling through the TGF-{beta} receptors independent of Smad proteins are essential for skeletal muscle differentiation.

  17. Recruitment of beta-arrestin2 to the dopamine D2 receptor: insights into anti-psychotic and anti-parkinsonian drug receptor signaling

    DEFF Research Database (Denmark)

    Klewe, Ib V; Nielsen, Søren M; Tarpø, Louise;

    2008-01-01

    of a Bioluminescence Resonance Energy Transfer (BRET) assay for measuring dopamine induced recruitment of human beta-arrestin2 to the human dopamine D2 receptor. Dopamine, as well as the dopamine receptor agonists pramipexole and quinpirole, acted as full agonists in the assay as reflected by their ability to elicit...

  18. Estrogen and the selective estrogen receptor modulator (SERM) protection against cell death in estrogen receptor alpha and beta expressing U2OS cells

    OpenAIRE

    Kallio, Anu; Guo, Tao; Lamminen, Elisa; Seppänen, Jani; Kangas, Lauri; Väänänen, H Kalervo; Härkönen, Pirkko

    2008-01-01

    Estrogen and the selective estrogen receptor modulator (SERM) protection against cell death in estrogen receptor alpha and beta expressing U2OS cells SWEDEN (Kallio, Anu) SWEDEN Received: 2007-12-01 Revised: 2008-03-12 Accepted: 2008-03-12

  19. Role of beta-arrestin 2 downstream of dopamine receptors in the basal ganglia

    Directory of Open Access Journals (Sweden)

    Thomas eDel'Guidice

    2011-09-01

    Full Text Available Multifunctional scaffolding protein beta-arrestins (βArr and the G protein receptor kinases (GRK are involved in the desensitization of several G protein coupled-receptors (GPCR. However, arrestins can also contribute to GPCR signaling independently from G proteins. In this review, we focus on the role of βArr in the regulation of dopamine receptor functions in the striatum. First, we present in vivo evidence supporting a role for these proteins in the regulation of dopamine receptor desensitization. Second, we provide an overview of the roles of βArr-2 in the regulation of ERK/MAPkinases and Akt/GSK3 signaling pathways downstream of the D1 and D2 dopamine receptors. Thereafter, we examine the possible involvement of βArr-mediated signaling in the action of dopaminergic drugs used for the treatment of mental disorders. Finally, we focus on different potential cellular proteins regulated by βArr-mediated signaling which could contribute to the regulation of behavioral responses to dopamine. Overall, the identification of a cell signaling function for βArr downstream of dopamine receptors underscores the intricate complexity of the intertwined mechanisms regulating and mediating cell signaling in the basal ganglia. Understanding these mechanisms may lead to a better comprehension of the several roles played by these structures in the regulation of mood and to the development of new psychoactive drugs having better therapeutic efficacy.

  20. Habituation of the C-start response in larval zebrafish exhibits several distinct phases and sensitivity to NMDA receptor blockade.

    Directory of Open Access Journals (Sweden)

    Adam C Roberts

    Full Text Available The zebrafish larva has been a valuable model system for genetic and molecular studies of development. More recently, biologists have begun to exploit the surprisingly rich behavioral repertoire of zebrafish larvae to investigate behavior. One prominent behavior exhibited by zebrafish early in development is a rapid escape reflex (the C-start. This reflex is mediated by a relatively simple neural circuit, and is therefore an attractive model behavior for neurobiological investigations of simple forms of learning and memory. Here, we describe two forms of short-lived habituation of the C-start in response to brief pulses of auditory stimuli. A rapid form, persisting for ≥1 min but <15 min, was induced by 120 pulses delivered at 0.5-2.0 Hz. A more extended form (termed "short-term habituation" here, which persisted for ≥25 min but <1 h, was induced by spaced training. The spaced training consisted of 10 blocks of auditory pulses delivered at 1 Hz (5 min interblock interval, 900 pulses per block. We found that these two temporally distinguishable forms of habituation are mediated by different cellular mechanisms. The short-term form depends on activation of N-methyl-d-aspartate receptors (NMDARs, whereas the rapid form does not.

  1. Simultaneous stimulation of GABA and beta adrenergic receptors stabilizes isotypes of activated adenylyl cyclase heterocomplex

    Directory of Open Access Journals (Sweden)

    Robichon Alain

    2004-06-01

    Full Text Available Abstract Background We investigated how the synthesis of cAMP, stimulated by isoproterenol acting through β-adrenoreceptors and Gs, is strongly amplified by simultaneous incubation with baclofen. Baclofen is an agonist of δ-aminobutyric acid type B receptors [GABAB], known to inhibit adenylyl cyclase via Gi. Because these agents have opposite effects on cAMP levels, the unexpected increase in cAMP synthesis when they are applied simultaneously has been intensively investigated. From previous reports, it appears that cyclase type II contributes most significantly to this phenomenon. Results We found that simultaneous application of isoproterenol and baclofen specifically influences the association/dissociation of molecules involved in the induction and termination of cyclase activity. Beta/gamma from [GABA]B receptor-coupled Gi has a higher affinity for adenylyl cyclase isoform(s when these isoforms are co-associated with Gs. Our data also suggest that, when beta/gamma and Gαs are associated with adenylyl cyclase isoform(s, beta/gamma from [GABA]B receptor-coupled Gi retards the GTPase activity of Gαs from adrenergic receptor. These reciprocal regulations of subunits of the adenylyl cyclase complex might be responsible for the drastic increase of cAMP synthesis in response to the simultaneous signals. Conclusions Simultaneous signals arriving at a particular synapse converge on molecular detectors of coincidence and trigger specific biochemical events. We hypothesize that this phenomenon comes from the complex molecular architectures involved, including scaffolding proteins that make reciprocal interactions between associated molecules possible. The biochemistry of simultaneous signaling is addressed as a key to synaptic function.

  2. Overexpression of estrogen receptor beta alleviates the toxic effects of beta-amyloid protein on PC12 cells via non-hormonal ligands

    Institute of Scientific and Technical Information of China (English)

    Hui Wang; Lihui Si; Xiaoxi Li; Weiguo Deng; Haimiao Yang; Yuyan Yang; Yan Fu

    2012-01-01

    After binding to the estrogen receptor, estrogen can alleviate the toxic effects of beta-amyloid protein, and thereby exert a therapeutic effect on Alzheimer's disease patients. Estrogen can increase the incidence of breast carcinoma and endometrial cancer in post-menopausal women, so it is not suitable for clinical treatment of Alzheimer's disease. There is recent evidence that the estrogen receptor can exert its neuroprotective effects without estrogen dependence. Real-time quantitative PCR and flow cytometry results showed that, compared with non-transfected PC12 cells, adenovirus-mediated estrogen receptor β gene-transfected PC12 cells exhibited lower expression of tumor necrosis factor α and interleukin 1β under stimulation with beta-amyloid protein and stronger protection from apoptosis. The Akt-specific inhibitor Abi-2 decreased the anti-inflammatory and anti-apoptotic effects of estrogen receptor β gene-transfection. These findings suggest that overexpression of estrogen receptor β can alleviate the toxic effect of beta-amyloid protein on PC12 cells, without estrogen dependence. The Akt pathway is one of the potential means for the anti-inflammatory and anti-apoptotic effects of the estrogen receptor.

  3. Regulation of dioxin receptor function by different beta-carboline alkaloids

    Energy Technology Data Exchange (ETDEWEB)

    Haarmann-Stemmann, Thomas; Goetz, Christine; Krug, Nathalie; Bothe, Hanno; Abel, Josef [Heinrich-Heine-Universitaet Duesseldorf gGmbH, Institut fuer Umweltmedizinische Forschung (IUF), Duesseldorf (Germany); Sendker, Jandirk; Proksch, Peter [Heinrich-Heine-Universitaet, Institut fuer Pharmazeutische Biologie und Biotechnologie, Duesseldorf (Germany); Fritsche, Ellen [Heinrich-Heine-Universitaet Duesseldorf gGmbH, Institut fuer Umweltmedizinische Forschung (IUF), Duesseldorf (Germany); University Hospital, RWTH Aachen, Department of Dermatology, Aachen (Germany)

    2010-08-15

    The dioxin receptor, also known as arylhydrocarbon receptor (AhR), is a ligand-activated transcription factor that mediates the toxicity of dioxins and related environmental contaminants. In addition, there is a growing list of natural compounds, mainly plant polyphenols that can modulate AhR function and downstream signaling with quite unknown consequences for cellular function. We investigate the potential of four different {beta}-carboline alkaloids to stimulate AhR signaling in human hepatoma cells and keratinocytes. Three test substances, namely rutaecarpine, annomontine and xestomanzamine A, increase AhR-driven reporter gene activity as well as expression of two AhR target genes in a dose-dependent and time-dependent manner. Additionally, the three test alkaloids stimulate cytochrome P450 (CYP) 1 enzyme activity without showing any antagonistic effects regarding benzo(a)pyrene-stimulated CYP1 activation. The AhR-activating property of the {beta}-carbolines is completely abrogated in AhR-deficient cells providing evidence that rutaecarpine, annomontine and xestomanzamine A are natural stimulators of the human AhR. The toxicological relevance of beta-carboline-mediated AhR activation is discussed. (orig.)

  4. Identification of alpha beta and gamma delta T cell receptor-positive cells

    DEFF Research Database (Denmark)

    Geisler, C; Larsen, J K; Plesner, T

    1988-01-01

    distribution and function of these different T cells. In immunofluorescence studies gamma delta TCR+ cells have been identified as CD3+WT-31- or CD3+CD4-CD8- cells. However, this may not be the optimal procedure because gamma delta TCR+ cells are weakly WT-31+, and some are CD8+. The aim of this study......Two lineages of T lymphocytes bearing the CD3 antigen can be defined on the basis of the nature of the heterodimeric receptor chain (alpha beta or gamma delta T cell receptor (TCR) expressed. Precise identification of alpha beta and gamma delta TCR+ cells is essential when studying the tissue...... was to evaluate a panel of monoclonal antibodies (MoAb) directed against different chains of the TCR-T3 complex for a more precise identification of alpha beta+ and gamma delta TCR+ cells in flow cytometric studies. We found that the MoAb anti-Ti-gamma A and delta-TCS-1, recognizing the TCR-gamma and the TCR...

  5. Genetic blockade of adenosine A2A receptors induces cognitive impairments and anatomical changes related to psychotic symptoms in mice.

    Science.gov (United States)

    Moscoso-Castro, Maria; Gracia-Rubio, Irene; Ciruela, Francisco; Valverde, Olga

    2016-07-01

    Schizophrenia is a chronic severe mental disorder with a presumed neurodevelopmental origin, and no effective treatment. Schizophrenia is a multifactorial disease with genetic, environmental and neurochemical etiology. The main theories on the pathophysiology of this disorder include alterations in dopaminergic and glutamatergic neurotransmission in limbic and cortical areas of the brain. Early hypotheses also suggested that nucleoside adenosine is a putative affected neurotransmitter system, and clinical evidence suggests that adenosine adjuvants improve treatment outcomes, especially in poorly responsive patients. Hence, it is important to elucidate the role of the neuromodulator adenosine in the pathophysiology of schizophrenia. A2A adenosine receptor (A2AR) subtypes are expressed in brain areas controlling motivational responses and cognition, including striatum, and in lower levels in hippocampus and cerebral cortex. The aim of this study was to characterize A2AR knockout (KO) mice with complete and specific inactivation of A2AR, as an animal model for schizophrenia. We performed behavioral, anatomical and neurochemical studies to assess psychotic-like symptoms in adult male and female KO and wild-type (WT) littermates. Our results show impairments in inhibitory responses and sensory gating in A2AR KO animals. Hyperlocomotion induced by d-amphetamine and MK-801 was reduced in KO animals when compared to WT littermates. Moreover, A2AR KO animals show motor disturbances, social and cognitive alterations. Finally, behavioral impairments were associated with enlargement of brain lateral ventricles and decreased BDNF levels in the hippocampus. These data highlight the role of adenosine in the pathophysiology of schizophrenia and provide new possibilities for the therapeutic management of schizophrenia. PMID:27133030

  6. Blockade of Toll-like receptor 2 prevents spontaneous cytokine release from rheumatoid arthritis ex vivo synovial explant cultures

    LENUS (Irish Health Repository)

    Nic An Ultaigh, Sinead

    2011-02-23

    Abstract Introduction The aim of this study was to examine the effect of blocking Toll-like receptor 2 (TLR2) in rheumatoid arthritis (RA) synovial cells. Methods RA synovial tissue biopsies, obtained under direct visualization at arthroscopy, were established as synovial explant cultures ex vivo or snap frozen for immunohistology. Mononuclear cell cultures were isolated from peripheral blood and synovial fluid of RA patients. Cultures were incubated with the TLR1\\/2 ligand, Pam3CSK4 (200 ng, 1 and 10 μg\\/ml), an anti-TLR2 antibody (OPN301, 1 μg\\/ml) or an immunoglobulin G (IgG) (1 μg\\/ml) matched control. The comparative effect of OPN301 and adalimumab (anti-tumour necrosis factor alpha) on spontaneous release of proinflammatory cytokines from RA synovial explants was determined using quantitative cytokine MSD multiplex assays or ELISA. OPN301 penetration into RA synovial tissue explants cultures was assessed by immunohistology. Results Pam3CSK4 significantly upregulated interleukin (IL)-6 and IL-8 in RA peripheral blood mononuclear cells (PBMCs), RA synovial fluid mononuclear cells (SFMCs) and RA synovial explant cultures (P < 0.05). OPN301 significantly decreased Pam3CSK4-induced cytokine production of tumour necrosis factor alpha (TNF-α), IL-1β, IL-6, interferon (IFN)-γ and IL-8 compared to IgG control in RA PBMCs and SFMCs cultures (all P < 0.05). OPN301 penetration of RA synovial tissue cultures was detected in the lining layer and perivascular regions. OPN301 significantly decreased spontaneous cytokine production of TNF-α, IL-1β, IFN-γ and IL-8 from RA synovial tissue explant cultures (all P < 0.05). Importantly, the inhibitory effect of OPN on spontaneous cytokine secretion was comparable to inhibition by anti-TNFα monoclonal antibody adalimumab. Conclusions These findings further support targeting TLR2 as a potential therapeutic agent for the treatment of RA.

  7. Hypoxia and glucose independently regulate the beta-adrenergic receptor-adenylate cyclase system in cardiac myocytes.

    OpenAIRE

    Rocha-Singh, K J; Honbo, N Y; Karliner, J S

    1991-01-01

    We explored the effects of two components of ischemia, hypoxia and glucose deprivation, on the beta-adrenergic receptor (beta AR)-adenylate cyclase system in a model of hypoxic injury in cultured neonatal rat ventricular myocytes. After 2 h of hypoxia in the presence of 5 mM glucose, cell surface beta AR density (3H-CGP-12177) decreased from 54.8 +/- 8.4 to 39 +/- 6.3 (SE) fmol/mg protein (n = 10, P less than 0.025), while cytosolic beta AR density (125I-iodocyanopindolol [ICYP]) increased by...

  8. The relationship between some beta-adrenergic mediated responses and plasma concentrations of adrenaline and cyclic AMP in man

    DEFF Research Database (Denmark)

    Philipsen, E K; Myhre, John Gabriel; Larsen, S;

    1990-01-01

    concentrations at low adrenaline infusion rates was prevented, whereas a small increase in cyclic AMP was found at high adrenaline infusion rates, probably owing to incomplete beta-receptor blockade. Likewise, the adrenaline-induced increments in blood substrates (glucose, lactate, glycerol and beta......To test the hypothesis that increments in plasma cyclic AMP during beta-adrenergic stimulation reflect integrated second messenger function of the tissues activated by the agonist, graded adrenaline infusion resulting in plasma adrenaline concentrations within the physiological range was performed...... hydroxybutyric acid) were significantly reduced but not completely prevented by beta-blockade. We conclude that an altered relationship between beta-agonist concentrations and plasma cyclic AMP may provide evidence for the existence of differences in beta-adrenergic sensitivity in man....

  9. Indices of brain beta-adrenergic receptor signal transduction in the learned helplessness animal model of depression.

    Science.gov (United States)

    Gurguis, G N; Kramer, G; Petty, F

    1996-01-01

    Both stress response and antidepressant drug action may be mediated by beta-adrenergic receptors (beta AR). Since learned helplessness is a stress-induced animal model of depression, beta AR are relevant to investigate in this model. To date, studies have measured changes in total receptor density (RT), but have not examined more detailed aspects of signal transduction mechanisms such as coupling of the receptor to GS protein. We have investigated brain beta AR coupling in the frontal cortex, hippocampus and hypothalamus of rats exposed to inescapable shock and then tested for learned helplessness, and in both tested and naive controls using [125I]-iodocyanopindolol (ICYP) as the ligand. Both antagonist-saturation and agonist-displacement experiments were conducted, and the specificity for the beta AR was optimized by excluding ICYP binding to 5HT1B receptors. The percentage receptor density in the high-conformational state (%RH) and the ratio of agonist (isoproterenol) dissociation constant from the receptor in the low-/high-conformational states (KL/KH) were used as indices of coupling to GS protein. No significant differences were found between rats developing learned helplessness and non-helpless rats after inescapable stress in any parameter measured in any brain region. In the frontal cortex, exposure to inescapable shock induced beta AR uncoupling from GS protein as suggested by a low KL/KH ratio both in helpless and non-helpless rats but not in either control group. In the hypothalamus, there were trends for higher RL, RT and KL/KH ratio in helpless rats and stressed controls compared to naive controls. These findings suggest that beta AR binding parameters in frontal cortex, hippocampus or hypothalamus did not differentiate between helpless and non-helpless rats. Changes in beta AR coupling observed in these brain regions may reflect effects of stress, which appeared to be region-specific, rather than stress-induced behavioral depression.

  10. 164Ile allele in the beta2-Adrenergic receptor gene is associated with risk of elevated blood pressure in women. The Copenhagen City Heart Study

    DEFF Research Database (Denmark)

    Sethi, Amar A; Tybjaerg-Hansen, Anne; Jensen, Gorm B;

    2005-01-01

    Since beta2-adrenergic receptors are important regulators of blood pressure, genetic variation in this receptor could explain risk of elevated blood pressure in selected individuals. We tested the hypothesis that Gly16Arg, Gln27Glu, and Thr164Ile in the beta2-adrenergic receptor gene associated w...

  11. Cell surface-bound TIMP3 induces apoptosis in mesenchymal Cal78 cells through ligand-independent activation of death receptor signaling and blockade of survival pathways.

    Directory of Open Access Journals (Sweden)

    Christina Koers-Wunrau

    exclusively cell surface-bound endogenous TIMP3 induces apoptosis in mesenchymal Cal78 cells through ligand-independent activation of death receptor signaling and blockade of survival signaling pathways.

  12. A member of the TGF-beta receptor gene family in the parasitic nematode Brugia pahangi.

    Science.gov (United States)

    Gomez-Escobar, N; van den Biggelaar, A; Maizels, R

    1997-10-15

    The full length cDNA sequence of a Type I transforming growth factor-beta (TGF-beta) receptor has been isolated from the filarial parasitic nematode Brugia pahangi. This new gene, designated Bp-trk-1, encodes a predicted 645 amino acid sequence with an N-terminal hydrophobic stretch which may act as a signal peptide. The extracellular portion (residues 15-187) is cysteine-rich and has three potential N-glycosylation sites. At positions 250-255 the protein contains the glycine-serine rich motif characteristic of Type I receptors. The closest homologue is a Caenorhabditis elegans gene (Q09488) in cosmid C32D5.2 which shares 67% amino acid identity with Bp-trk-1 in the most conserved kinase domain (aa 259-482). Other type I receptors such as C. elegans daf-1 and Drosophila tkv show 38-53% identity in the same region. Some residues conserved in Drosophila and vertebrates are not present in the B. pahangi sequence. RT-PCR amplification has been used to show that the transcript is expressed in the three main stages of the B. pahangi life cycle: microfilariae, infective larvae and adults. The ligand remains unknown at this time but is likely to be most similar to that for C. elegans Q09488. PMID:9358045

  13. Beta-adrenoceptor blockade and psychic stress in man. A comparison of the acute effects of labetalol, metoprolol, pindolol and propranolol on plasma levels of adrenaline and noradrenaline.

    OpenAIRE

    Trap-Jensen, J; Carlsen, J E; Hartling, O J; Svendsen, T L; Tangø, M; Christensen, N J

    1982-01-01

    1 A random double-blind study was performed in healthy volunteers. The immediate effects of three different beta-adrenoceptor blocking agents, metoprolol, pindolol and propranolol, on the plasma concentrations of adrenaline and noradrenaline were compared in a situation of pleasant psychic stimulation during a television-game of tennis. The immediate effects of labetalol in a group of patients with arterial hypertension were studied in a similar experimental situation. 2 During psychic stress...

  14. Beta-arrestin-mediated activation of MAPK by inverse agonists reveals distinct active conformations for G protein-coupled receptors.

    OpenAIRE

    Azzi, Mounia; Pascale G. Charest; Angers, Stéphane; Rousseau, Guy; Kohout, Trudy; Bouvier, Michel; Piñeyro, Graciela

    2003-01-01

    It is becoming increasingly clear that signaling via G protein-coupled receptors is a diverse phenomenon involving receptor interaction with a variety of signaling partners. Despite this diversity, receptor ligands are commonly classified only according to their ability to modify G protein-dependent signaling. Here we show that beta2AR ligands like ICI118551 and propranolol, which are inverse agonists for Gs-stimulated adenylyl cyclase, induce partial agonist responses for the mitogen-activat...

  15. Structure of the T cell receptor in a Ti alpha V beta 2, alpha V beta 8-positive T cell line

    DEFF Research Database (Denmark)

    Hou, X; Dietrich, J; Kuhlmann, J;

    1994-01-01

    not known; however, it has been suggested that each TcR contains two Ti dimers. To gain insight into the structure of the TcR we constructed a Ti alpha V beta 2, alpha V beta 8-positive T cell line which expressed the endogenous human TiV beta 8 and the transfected mouse TiV beta 2 both in association......The T cell receptor (TcR) is composed of at least six different polypeptide chains consisting of the clonotypic Ti heterodimer (Ti alpha beta or Ti gamma delta) and the noncovalently associated CD3 chains (CD3 gamma delta epsilon zeta). The exact number of subunits constituting the TcR is still...... with the endogenous Ti alpha and CD3 chains at the cell surface. Preclearing experiments with radioiodinated cell lysate prepared with digitonin lysis buffer demonstrated that depleting the lysate of Ti alpha V beta 8 by immunoprecipitation with anti V beta 8 monoclonal antibody (mAb) did not reduce the amount of Ti...

  16. Roles of oestrogen receptors alpha and beta in behavioural neuroendocrinology: beyond Yin/Yang.

    Science.gov (United States)

    Rissman, E F

    2008-06-01

    Oestrogen receptor beta (ERbeta) was discovered more than 10 years ago. It is widely distributed in the brain. In some areas, such as the entorhinal cortex, it is present as the only ER, whereas in other regions, such as the bed nucleus of the stria terminalis and preoptic area, it can be found co-expressed with ERalpha, often within the same neurones. These ERs share ligands, and there are several complex relationships between the two receptors. Initially, the relationship between them was labelled as 'yin/yang', meaning that the actions of each complemented those of the other, but now, years later, other relationships have been described. Based on evidence from neuroendocrine and behavioural studies, three types of interactions between the two oestrogen receptors are described in this review. The first relationship is antagonistic; this is evident from studies on the role of oestrogen in spatial learning. When oestradiol is given in a high, chronic dose, spatial learning is impaired. This action of oestradiol requires ERalpha, and when ERbeta is not functional, lower doses of oestradiol have this negative effect on behaviour. The second relationship between the two receptors is one that is synergistic, and this is illustrated in the combined effects of the two receptors on the production of the neuropeptide oxytocin and its receptor. The third relationship is sequential; separate actions of the two receptors are postulated in activation and organisation of sexually dimorphic reproductive behaviours. Future studies on all of these topics will inform us about how ER selective ligands might affect oestrogen functions at the organismal level.

  17. Enhanced negative chronotropy by inhibitory receptors in transgenic heart overexpressing beta(2)-adrenoceptors.

    Science.gov (United States)

    Du, X J; Vincan, E; Percy, E; Woodcock, E A

    2000-03-15

    Transgenic (TG) mice overexpressing beta(2)-adrenoceptors (AR) in the heart have enhanced beta-adrenergic activity. Since the degree of beta-adrenergic activation influences the negative chronotropic control of heart rate (HR), we studied the inhibitory effect of cholinergic and purinergic stimulation on HR in TG and wild-type (WT) control mice. Bradycardia in response to vagal nerve stimulation and administration of acetylcholine or adenosine was studied in anesthetised animals and perfused hearts. Basal HR was significantly higher in TG than WT mice (P<0.01). Electrical stimulation of vagal nerves (1-32 Hz) induced a Hz-dependent reduction in HR and the response was more pronounced in TG than WT groups (P<0.01). In perfused hearts, HR reduction by acetylcholine (ACh) was more pronounced with EC(50) 110-fold lower in TG than WT hearts. Adenosine-induced bradycardia, which was abolished by a P(1) antagonist, was more pronounced in TG hearts. After pre-treatment with pertussis toxin (PT, 100 microg/kg), bradycardia by vagal nerve stimulation or ACh remained unchanged in WT, but markedly inhibited in TG hearts (both P<0.01). Conversely, inhibiting guanylyl cyclase with LY83583 (30 microM) or nitric oxide synthase with L-NMMA (100 microM) attenuated HR reduction by vagal nerve stimulation in WT but not in TG hearts. Immunobloting assay showed similar G(ialpha2) abundance in TG and WT hearts. Thus, cardiac overexpression of beta(2)AR with high beta-adrenergic activity leads to hypersensitivity of inhibitory receptors controlling HR due to increase in activity of PT-sensitive G-proteins.

  18. Troglitazone stimulates {beta}-arrestin-dependent cardiomyocyte contractility via the angiotensin II type 1{sub A} receptor

    Energy Technology Data Exchange (ETDEWEB)

    Tilley, Douglas G., E-mail: douglas.tilley@jefferson.edu [Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University (United States); Center for Translational Medicine, Thomas Jefferson University (United States); Nguyen, Anny D. [Department of Pharmaceutical Sciences, Jefferson School of Pharmacy, Thomas Jefferson University (United States); Rockman, Howard A. [Department of Medicine, Duke University Medical Center (United States); Department of Cell Biology, Duke University Medical Center (United States); Department of Molecular Genetics and Microbiology, Duke University Medical Center (United States)

    2010-06-11

    Peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}) agonists are commonly used to treat cardiovascular diseases, and are reported to have several effects on cardiovascular function that may be due to PPAR{gamma}-independent signaling events. Select angiotensin receptor blockers (ARBs) interact with and modulate PPAR{gamma} activity, thus we hypothesized that a PPAR{gamma} agonist may exert physiologic effects via the angiotensin II type 1{sub A} receptor (AT1{sub A}R). In AT1{sub A}R-overexpressing HEK 293 cells, both angiotensin II (Ang II) and the PPAR{gamma} agonist troglitazone (Trog) enhanced AT1{sub A}R internalization and recruitment of endogenous {beta}-arrestin1/2 ({beta}arr1/2) to the AT1{sub A}R. A fluorescence assay to measure diacylglycerol (DAG) accumulation showed that although Ang II induced AT1{sub A}R-G{sub q} protein-mediated DAG accumulation, Trog had no impact on DAG generation. Trog-mediated recruitment of {beta}arr1/2 was selective to AT1{sub A}R as the response was prevented by an ARB- and Trog-mediated {beta}arr1/2 recruitment to {beta}1-adrenergic receptor ({beta}1AR) was not observed. In isolated mouse cardiomyocytes, Trog increased both % and rate of cell shortening to a similar extent as Ang II, effects which were blocked with an ARB. Additionally, these effects were found to be {beta}arr2-dependent, as cardiomyocytes isolated from {beta}arr2-KO mice showed blunted contractile responses to Trog. These findings show for the first time that the PPAR{gamma} agonist Trog acts at the AT1{sub A}R to simultaneously block G{sub q} protein activation and induce the recruitment of {beta}arr1/2, which leads to an increase in cardiomyocyte contractility.

  19. Biology of common beta receptor-signaling cytokines: IL-3, IL-5, and GM-CSF.

    Science.gov (United States)

    Martinez-Moczygemba, Margarita; Huston, David P

    2003-10-01

    IL-3, IL-5, and GM-CSF are related hematopoietic cytoines that are important for allergic inflammation. The receptors for human IL-5, IL-3, and GM-CSF are members of the hematopoietin receptor superfamily and are comprised of a cytokine-specific alpha chain and the common beta chain that is shared among these cytokines for signaling. Each of these cytokines contributes to the differentiation and function of leukocyte subpopulations and have clinical importance in protective immunity and in the pathophysiology of a spectrum of immunologic diseases that are as diverse as allergy and asthma, pulmonary alveolar proteinosis, neurodegenerative diseases, and malignancies. Delineating the biology of these cytokines is enabling the development of new strategies for diagnosing and treating these diseases and modulating immune responses. PMID:14564341

  20. Blockade of NMDA receptor subtype NR2B prevents seizures but not apoptosis of dentate gyrus neurons in bacterial meningitis in infant rats

    Directory of Open Access Journals (Sweden)

    Täuber Martin G

    2003-09-01

    Full Text Available Abstract Background Excitotoxic neuronal injury by action of the glutamate receptors of the N-methyl-d-aspartate (NMDA subtype have been implicated in the pathogenesis of brain damage as a consequence of bacterial meningitis. The most potent and selective blocker of NMDA receptors containing the NR2B subunit is (R,S-alpha-(4-hydroxyphenyl-beta-methyl-4-(phenylmethyl-1-piperid inepropanol (RO 25-6981. Here we evaluated the effect of RO 25-6981 on hippocampal neuronal apoptosis in an infant rat model of meningitis due to Streptococcus pneumoniae. Animals were randomized for treatment with RO 25-6981 at a dosage of either 0.375 mg (15 mg/kg; n = 28 or 3.75 mg (150 mg/kg; n = 15 every 3 h or an equal volume of sterile saline (250 μl; n = 40 starting at 12 h after infection. Eighteen hours after infection, animals were assessed clinically and seizures were observed for a period of 2 h. At 24 h after infection animals were sacrificed and brains were examined for apoptotic injury to the dentate granule cell layer of the hippocampus. Results Treatment with RO 25-6981 had no effect on clinical scores, but the incidence of seizures was reduced (P Conclusions Treatment with a highly selective blocker of NMDA receptors containing the NR2B subunit failed to protect hippocampal neurons from injury in this model of pneumococcal meningitis, while it had some beneficial effect on the incidence of seizures.

  1. Absence of transforming growth factor-beta type II receptor is associated with poorer prognosis in HER2-negative breast tumours

    DEFF Research Database (Denmark)

    Paiva, C E; Drigo, S A; Rosa, F E;

    2010-01-01

    BACKGROUND: The clinical relevance of transforming growth factor-beta (TGF-beta)-signalling pathway in breast carcinomas (BCs) remained elusive. This study aimed to evaluate the prognostic value of TGF-beta1 and transforming growth factor-beta type II receptor (TGF-betaRII) expression levels...... in tumour cells and their association with the established biomarkers in BC. PATIENTS AND METHODS: In 324 BC from patients with long-term follow-up, the TGF-beta1 and TGF-betaRII transcript and protein expression levels were assessed. RESULTS: TGF-beta1 and TGF-betaRII down-expression was significantly...... associated with BC. Negative TGF-beta1 and TGF-betaRII protein status was associated with the development of distant metastasis (P = 0.003 and P = 0.029, respectively). In multivariate analysis, TGF-beta1-positive tumours were associated with increased disease-free survival (DFS) [hazard ratio (HR) = 0...

  2. Citalopram-induced hypophagia is enhanced by blockade of 5-HT1A receptors: role of 5-HT2C receptors

    OpenAIRE

    Grignaschi, G.; Invernizzi, R W; Fanelli, E.; Fracasso, C; Caccia, S.; Samanin, R.

    1998-01-01

    The selective 5-hydroxytryptamine reuptake inhibitor citalopram (10 and 20 mg kg−1, i.p.) significantly reduced food intake in male rats (CD-COBS) habituated to eat their daily food during a 4-h period.The 5-HT1A receptor antagonist WAY100635 (0.3 mg kg−1) administered systemically did not modify feeding but significantly potentiated the reduction in food intake caused by 10 mg kg−1 i.p. citalopram. The dose of 5 mg kg−1 i.p. citalopram was not active in animals pretreated with vehicle but si...

  3. Dopaminergic and beta-adrenergic effects on gastric antral motility

    DEFF Research Database (Denmark)

    Bech, K; Hovendal, C P; Gottrup, F;

    1984-01-01

    bethanechol or pentagastrin inducing motor activity patterns as in the phase III of the MMC and the digestive state respectively. The stimulated antral motility was dose-dependently inhibited by dopamine. The effect was significantly blocked by specifically acting dopaminergic blockers, while alpha- and beta......-adrenergic blockers were without any significant effects. Dose-response experiments with bethanechol and dopamine showed inhibition of a non-competitive type. Isoprenaline was used alone and in conjunction with selective blockade of beta 1- and beta 2-receptors during infusion of bethanechol which induces a pattern...... similar to phase III in the migrating myoelectric complex. The stimulated antral motility was dose-dependently inhibited by isoprenaline. The effect could be significantly blocked by propranolol (beta 1 + beta 2-adrenoceptor blocker) and by using in conjunction the beta 1-adrenoceptor blocker practolol...

  4. Neonatal NMDA receptor blockade disrupts spike timing and glutamatergic synapses in fast spiking interneurons in a NMDA receptor hypofunction model of schizophrenia.

    Directory of Open Access Journals (Sweden)

    Kevin S Jones

    Full Text Available The dysfunction of parvalbumin-positive, fast-spiking interneurons (FSI is considered a primary contributor to the pathophysiology of schizophrenia (SZ, but deficits in FSI physiology have not been explicitly characterized. We show for the first time, that a widely-employed model of schizophrenia minimizes first spike latency and increases GluN2B-mediated current in neocortical FSIs. The reduction in FSI first-spike latency coincides with reduced expression of the Kv1.1 potassium channel subunit which provides a biophysical explanation for the abnormal spiking behavior. Similarly, the increase in NMDA current coincides with enhanced expression of the GluN2B NMDA receptor subunit, specifically in FSIs. In this study mice were treated with the NMDA receptor antagonist, MK-801, during the first week of life. During adolescence, we detected reduced spike latency and increased GluN2B-mediated NMDA current in FSIs, which suggests transient disruption of NMDA signaling during neonatal development exerts lasting changes in the cellular and synaptic physiology of neocortical FSIs. Overall, we propose these physiological disturbances represent a general impairment to the physiological maturation of FSIs which may contribute to schizophrenia-like behaviors produced by this model.

  5. Up and Down Expression of Androgen Receptor,Estrogen Receptor beta and Platelet Derived Growth Factor beta by Testosterone in Aortic Vascular Smooth Muscle Tissues

    Institute of Scientific and Technical Information of China (English)

    Wu Saizhu; Lv Hongsong; Zhou Kexiang; Sun Fei; Ma Rui; Zheng Hua; Wei Heming; Rong Zhiyi

    2004-01-01

    Objectives To investigate the effects of testosterone enanthate(TE) on serum lipids and lipoproteins metabolism and the expression of androgen receptor ( AR), estrogen receptor beta ( ER -β) and platelet derived growth factor beta (PDGFR-β ) in aortic vascular smooth muscle tissues(VSMTs). Methods Forty aged male rats were randomly divided into 4 groups, group A (placebo group),group B (2.5 mg/kg intramuscular injection of TE once a week ), group C (5.0 mg/kg intramuscular injection of TE once a week ), group D ( 10.0 mg,/kg intramuscular injection of TE once a week). All animals were fed freely during 16 - week treatment periods. The expression of AR , ER - βand PDGFR - β were studied by Western bolt. Results Average serum LDL - C was lower in group D than that in group A ( p < 0.01 ).Compared with the other groups, average serum TC was also lower in group D ( p < 0.05). AR expression in aortic vascular smooth muscle tissues could be regulated by TE: 99.50 ± 21.74, 125.38 ± 28.68 and 101.98 ±15.42 for TE concentrations at 2.5 mg/kg, 5.0 mg/kgand 10.0 mg/kg, respectively , the expression of ER -β could be regulated by TE: 92.34 ± 18.68, 47.72 ±18.12, 82.13 ±23.50, and the expression of PDGFR -β could be regulated as well by TE: 219.70 ± 45.59,50.16 ± 9.72, 125.36 ± 15.74 ( Data for AR , ER - βand PDGFR - β protein band intensity were expressed with x ± s, with control group taken as 100).Conclusions This study indicates that androgens have significant effects on serum lipids and lipoprotein metabolism. Testosterone enanthate at 5.0 mg/kg can stimulate the expression of AR, but inhibite the expression of PDGFR. Testosterone enanthate at the concentrations of 5.0 mg/kg and 10.0 mg/kg can inhibite the expression of ER - β.

  6. Combined renin inhibition/(pro)renin receptor blockade in diabetic retinopathy--a study in transgenic (mREN2)27 rats.

    Science.gov (United States)

    Batenburg, Wendy W; Verma, Amrisha; Wang, Yunyang; Zhu, Ping; van den Heuvel, Mieke; van Veghel, Richard; Danser, A H Jan; Li, Qiuhong

    2014-01-01

    Dysfunction of renin-angiotensin system (RAS) contributes to the pathogenesis of diabetic retinopathy (DR). Prorenin, the precursor of renin is highly elevated in ocular fluid of diabetic patients with proliferative retinopathy. Prorenin may exert local effects in the eye by binding to the so-called (pro)renin receptor ((P)RR). Here we investigated the combined effects of the renin inhibitor aliskiren and the putative (P)RR blocker handle-region peptide (HRP) on diabetic retinopathy in streptozotocin (STZ)-induced diabetic transgenic (mRen2)27 rats (a model with high plasma prorenin levels) as well as prorenin stimulated cytokine expression in cultured Müller cells. Adult (mRen2)27 rats were randomly divided into the following groups: (1) non-diabetic; (2) diabetic treated with vehicle; (3) diabetic treated with aliskiren (10 mg/kg per day); and (4) diabetic treated with aliskiren+HRP (1 mg/kg per day). Age-matched non-diabetic wildtype Sprague-Dawley rats were used as control. Drugs were administered by osmotic minipumps for three weeks. Transgenic (mRen2)27 rat retinas showed increased apoptotic cell death of both inner retinal neurons and photoreceptors, increased loss of capillaries, as well as increased expression of inflammatory cytokines. These pathological changes were further exacerbated by diabetes. Aliskiren treatment of diabetic (mRen2)27 rats prevented retinal gliosis, and reduced retinal apoptotic cell death, acellular capillaries and the expression of inflammatory cytokines. HRP on top of aliskiren did not provide additional protection. In cultured Müller cells, prorenin significantly increased the expression levels of IL-1α and TNF-α, and this was completely blocked by aliskiren or HRP, their combination, (P)RR siRNA and the AT1R blocker losartan, suggesting that these effects entirely depended on Ang II generation by (P)RR-bound prorenin. In conclusion, the lack of effect of HRP on top of aliskiren, and the Ang II-dependency of the ocular

  7. Polimorfismos del receptor adrenérgico beta-1 y sus implicaciones farmacodinámicas

    Directory of Open Access Journals (Sweden)

    Ignacio Rodríguez

    2001-04-01

    Full Text Available Los betabloqueadores son fármacos que han demostrado eficacia
    clínica al disminuir tanto la morbilidad como la mortalidad de múltiples enfermedades cardiovasculares. Como común denominador todos los bloqueadores beta adrenérgicos antagonizan los receptores β1, produciendo en el corazón
    una respuesta inotrópica y cronotrópica negativas. Hasta la fecha se han reportado siete polimorfismos en este receptor β1 (1. En uno de ellos, la sustitución en el nucleótido 1165, genera un cambio de Arginina por Glicina en la posición 389 (Arg389Gly localizado en la cola citoplasmática del receptor que es una de las regiones de interacción con la proteína G. Estudios in vitro con las
    dos variantes polimórficas Arg389Gly del receptor, han demostrado que los receptores con Arg389 tienen una mayor interacción con la proteína G y producen más AMPc luego del estímulo con agonistas β(2. En la actualidad se desconocen tanto las implicaciones farmacoterapéuticas de estos polimorfismos, como sus frecuencias alélicas en poblaciones latinoamericanas. Este estudio pretende evaluar la frecuencia de los polimorfismos en la posición 1165 en
    individuos colombianos, y determinar si tales cambios desencadenan alguna variación en la respuesta a un medicamento bloqueador de los receptores β1 adrenérgicos.

  8. [The association between beta-adrenergic receptor gene polymorphisms and personality traits].

    Science.gov (United States)

    Numajiri, Maki; Aoki, Jun; Nishizawa, Daisuke; Kasai, Shinya; Ogai, Yasukazu; Ikeda, Kazutaka; Iwahashi, Kazuhiko

    2012-08-01

    The relationship between the polymorphisms (SNPs) of the beta-adrenergic receptor (beta-AR) gene and personality assessed by TCI (Temperament and Character Inventory), was studied among 192 healthy Japanese subjects (121 male subjects and 71 female subjects). In this study, the statistical analyses were performed overall and separately for each sex. As a result, it was shown that there were significant relationships between SD (self-directedness) and 49Ser/Gly (rs1801252) in ADRB1, P (persistence) and 389Arg/Gly (rs1801253) in ADRB1, and ST (self-transcendence) and 27Gln/Glu (rs1042714) in ADRB2 overall. Among the male subjects, there were further significant relationships between ST and 49Ser/Gly in ADRB1, NS (novelty-seeking), HA (harm avoidance) and P and 389Arg/Gly in ADRB1, and P and 64Arg/Trp(rsrs4994) in ADRB3. Among the female subjects, there were also significant relationships between SD and 49Ser/Gly in ADRB1, and C (cooperativeness) and 389Arg/Gly in ADRB1. Thus it was shown that there were correlations between beta-AR gene polymorphisms and several subscales of TCI. PMID:23012891

  9. Mycophenolate mofetil modulates adhesion receptors of the beta1 integrin family on tumor cells: impact on tumor recurrence and malignancy

    International Nuclear Information System (INIS)

    Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF) on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a), alpha2beta1 (CD49b), alpha3beta1 (CD49c), alpha4beta1 (CD49d), alpha5beta1 (CD49e), and alpha6beta1 (CD49f) receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype

  10. Mycophenolate mofetil modulates adhesion receptors of the beta1 integrin family on tumor cells: impact on tumor recurrence and malignancy

    Directory of Open Access Journals (Sweden)

    Beecken Wolf-Dietrich

    2005-01-01

    Full Text Available Abstract Background Tumor development remains one of the major obstacles following organ transplantation. Immunosuppressive drugs such as cyclosporine and tacrolimus directly contribute to enhanced malignancy, whereas the influence of the novel compound mycophenolate mofetil (MMF on tumor cell dissemination has not been explored. We therefore investigated the adhesion capacity of colon, pancreas, prostate and kidney carcinoma cell lines to endothelium, as well as their beta1 integrin expression profile before and after MMF treatment. Methods Tumor cell adhesion to endothelial cell monolayers was evaluated in the presence of 0.1 and 1 μM MMF and compared to unstimulated controls. beta1 integrin analysis included alpha1beta1 (CD49a, alpha2beta1 (CD49b, alpha3beta1 (CD49c, alpha4beta1 (CD49d, alpha5beta1 (CD49e, and alpha6beta1 (CD49f receptors, and was carried out by reverse transcriptase-polymerase chain reaction, confocal microscopy and flow cytometry. Results Adhesion of the colon carcinoma cell line HT-29 was strongly reduced in the presence of 0.1 μM MMF. This effect was accompanied by down-regulation of alpha3beta1 and alpha6beta1 surface expression and of alpha3beta1 and alpha6beta1 coding mRNA. Adhesion of the prostate tumor cell line DU-145 was blocked dose-dependently by MMF. In contrast to MMF's effects on HT-29 cells, MMF dose-dependently up-regulated alpha1beta1, alpha2beta1, alpha3beta1, and alpha5beta1 on DU-145 tumor cell membranes. Conclusion We conclude that MMF possesses distinct anti-tumoral properties, particularly in colon and prostate carcinoma cells. Adhesion blockage of HT-29 cells was due to the loss of alpha3beta1 and alpha6beta1 surface expression, which might contribute to a reduced invasive behaviour of this tumor entity. The enhancement of integrin beta1 subtypes observed in DU-145 cells possibly causes re-differentiation towards a low-invasive phenotype.

  11. beta. -adrenergic receptor-mediated hepatic glycogenolysis is increased in aged male rats

    Energy Technology Data Exchange (ETDEWEB)

    Herring, P.A.; Graham, S.M.; Arinze, I.J.

    1986-03-05

    The effect of age on catecholamine-stimulated glycogenolysis was studied in isolated hepatocytes prepared from 3, 12, and 24 month-old rats. Glucose release was stimulated by epinephrine and norepinephrine, this was inhibited by phentolamine and prazosin. Isoproterenol (ISO) stimulated glycogenolysis only in cells from 24 month-old rats, this was blocked by propranolol. In liver plasma membranes, binding of (/sup 3/H)yohimbine (100-130 fmol/mg protein) did not change with age, whereas (/sup 3/H)prazosin binding decreased from 870 fmol/mg at 3 months to 435 fmol/mg at 12 months, but subsequently rose to 656 fmol/mg at 24 months. (/sup 125/I)Cyanopindolol binding increased from 8 fmol/mg at 3 months to 19 fmol/mg at 24 months. The proportion of ..beta..-receptors in the high affinity state increased from 28% at 3 months to 42% at 24 months. ISO stimulated adenylate cyclase at 24 months but not at 3 months. Basal, fluoride-, GTP-, and Gpp(NH)p-stimulated activities were 1.4- to 2.4-fold greater at 24 months than at 3 months. These results suggest an age-related increase in the sensitivity of adenylate cyclase to ..beta..-receptor stimulation.

  12. Glucocorticoids and beta-adrenergic-receptor agonists: their combined effect on fetal rabbit lung surfactant.

    Science.gov (United States)

    Ekelund, L; Enhorning, G

    1985-08-15

    In a previous study on pregnant rabbits (Am J Obstet Gynecol 1983; 147:437) we found that a prolonged infusion of the beta 2-adrenergic-receptor agonist terbutaline would first cause a release of fetal pulmonary surfactant, so that more was available in the airways. However, the airway fluid then contained less surfactant, indicating a depletion of stores. Since terbutaline is often used in high doses as a tocolytic agent, surfactant depletion could be a serious side effect. With further studies on rabbits, we wanted to test the hypothesis that with an accelerated surfactant synthesis, achieved with glucocorticoids, the increased release, evoked with the terbutaline, would never cause a depletion of the surfactant stores. Our results supported this hypothesis. Betamethasone, administered to the pregnant doe on the twenty-sixth and twenty-seventh days of gestation, 0.1 mg/kg, increased compliance of the fetal lungs, and more phospholipid phosphorus could be lavaged from the airways. These effects were further increased when, following steroid administration, the doe was infused with terbutaline. Depletion of the surfactant stores was never seen when betamethasone was given prior to the beta-adrenergic-receptor agonist. PMID:3839627

  13. Determination of beta-adrenergic receptor blocking pharmaceuticals in united states wastewater effluent

    International Nuclear Information System (INIS)

    This is the first report of beta-adrenergic receptor antagonist pharmaceuticals in United States wastewater effluent. - Beta adrenergic receptor antagonists (β-Blockers) are frequently prescribed medications in the United States and have been identified in European municipal wastewater effluent, however no studies to date have investigated these compounds in United States wastewater effluent. Municipal wastewater effluent was collected from treatment facilities in Mississippi, Texas, and New York to investigate the occurrence of metoprolol, nadolol, and propranolol. Propranolol was identified in all wastewater samples analyzed (n=34) at concentrations ≤1.9 μg/l. Metoprolol and nadolol were identified in ≥71% of the samples with concentrations of metoprolol ≤1.2 μg/l and nadolol ≤0.36 μg/l. Time course studies at both Mississippi plants and the Texas plant indicate that concentrations of propranolol, metoprolol, and nadolol remain relatively constant at each sampling period. This study indicates that β-Blockers are present in United States wastewater effluent in the ng/l to μg/l range

  14. Rapid effects of phytoestrogens on human colonic smooth muscle are mediated by oestrogen receptor beta.

    LENUS (Irish Health Repository)

    Hogan, A M

    2012-02-01

    Epidemiological studies have correlated consumption of dietary phytoestrogens with beneficial effects on colon, breast and prostate cancers. Genomic and non-genomic mechanisms are responsible for anti-carcinogenic effects but, until now, the effect on human colon was assumed to be passive and remote. No direct effect on human colonic smooth muscle has previously been described. Institutional research board approval was granted. Histologically normal colon was obtained from the proximal resection margin of colorectal carcinoma specimens. Circular smooth muscle strips were microdissected and suspended under 1g of tension in organ baths containing oxygenated Krebs solution at 37 degrees C. After an equilibration period, tissues were exposed to diarylpropionitrile (DPN) (ER beta agonist) and 1,3,5-tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole (PPT) (ER alpha agonist) or to the synthetic phytoestrogen compounds genistein (n=8), daidzein (n=8), fisetin (n=8) and quercetin (n=8) in the presence or absence of fulvestrant (oestrogen receptor antagonist). Mechanism of action was investigated by inhibition of downstream pathways. The cholinergic agonist carbachol was used to induce contractile activity. Tension was recorded isometrically. Phytoestrogens inhibit carbachol-induced colonic contractility. In keeping with a non-genomic, rapid onset direct action, the effect was within minutes, reversible and similar to previously described actions of 17 beta oestradiol. No effect was seen in the presence of fulvestrant indicating receptor modulation. While the DPN exerted inhibitory effects, PPT did not. The effect appears to be reliant on a p38\\/mitogen activated protein kinase mediated induction of nitric oxide production in colonic smooth muscle. The present data set provides the first description of a direct effect of genistein, daidzein, fisetin and quercetin on human colonic smooth muscle. The presence of ER in colonic smooth muscle has been functionally proven and the beta

  15. Different expression of mu-opiate receptor in chronic and acute wounds and the effect of beta-endorphin on transforming growth factor beta type II receptor and cytokeratin 16 expression.

    Science.gov (United States)

    Bigliardi, P L; Sumanovski, L T; Büchner, S; Rufli, T; Bigliardi-Qi, M

    2003-01-01

    There is evidence that neuropeptides, especially the opiate receptor agonists, are involved in wound healing. We have previously observed that beta-endorphin, the endogenous ligand for the mu-opiate receptor, stimulates the expression of cytokeratin 16 in a dose-dependent manner in human skin organ cultures. Cytokeratin 16 is expressed in hyperproliferative epidermis such as psoriasis and wound healing. Therefore we were interested to study whether epidermal mu-opiate receptor expression is changed at the wound margins in acute and chronic wounds. Using classical and confocal microscopy, we were able to compare the expression level of mu-opiate receptors and the influence of beta-endorphin on transforming growth factor beta type II receptor in organ culture. Our results show indeed a significantly decreased expression of mu-opiate receptors on keratinocytes close to the wound margin of chronic wounds compared to acute wounds. Additionally beta-endorphin upregulates the expression of transforming growth factor beta type II receptor in human skin organ cultures. These results suggest a crucial role of opioid peptides not only in pain control but also in wound healing. Opioid peptides have already been used in animal models in treatment of wounds; they induce fibroblast proliferation and growth of capillaries, and accelerate the maturation of granulation tissue and the epithelization of the defect. Furthermore opioid peptides may fine-tune pain and the inflammatory response while healing takes place. This new knowledge could potentially be used to design new locally applied drugs to improve the healing of painful chronic wounds.

  16. Actinomyces tissue specificity may depend on differences in receptor specificity for GalNAc beta-containing glycoconjugates.

    OpenAIRE

    Strömberg, N.; Borén, T

    1992-01-01

    Actinomyces naeslundii 12104 and A. viscosus LY7 were compared for receptor specificities and adherence properties because these relate to their oral colonization sites. Both strains bind GalNAc beta-containing glycosphingolipids (GSLs) in a GalNAc beta 1-3Gal alpha Oethyl-sensitive fashion but differ with respect to the number of cells bound to GSLs and the effect of neighboring sugar groups on the binding. Their hemagglutination and saccharide inhibition profiles confirms the existence of t...

  17. Simultaneous blockade of the epidermal growth factor receptor/mammalian target of rapamycin pathway by epidermal growth factor receptor inhibitors and rapamycin results in reduced cell growth and survival in biliary tract cancer cells.

    Science.gov (United States)

    Herberger, Beata; Berger, Walter; Puhalla, Harald; Schmid, Katharina; Novak, Sabine; Brandstetter, Anita; Pirker, Christine; Gruenberger, Thomas; Filipits, Martin

    2009-06-01

    The prognosis of patients with biliary tract adenocarcinomas (BTA) is still poor due to lack of effective systemic treatment options. Knowledge of the molecular mechanisms involved in the pathogenesis of this disease is of importance for the development of new treatment strategies. We determined the expression of epidermal growth factor receptor (EGFR) and activated mammalian target of rapamycin (p-mTOR) in paraffin-embedded surgical specimens of BTA (n = 89) by immunohistochemistry. Overall survival was analyzed with Cox models adjusted for clinical and pathologic factors. Combined EGFR/p-mTOR expression was significantly associated with relapse-free survival [adjusted hazard ratio for relapse, 2.20; 95% confidence interval (95% CI), 1.45-3.33; P BTA cell lines was tested in short-term 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays and long-term colony formation assays. Simultaneous blockade of EGFR and mTOR in biliary tract cancer cell lines results in a synergistic inhibition of both phosphatidylinositol-3-kinase and mitogen-activated protein kinase pathways, leading to reduced cell growth and survival. These results suggest that combined targeted therapy with EGFR and mTOR inhibitors may potentially benefit patients with BTAs and should be further evaluated in clinical trials.

  18. Adaptations to iron deficiency: cardiac functional responsiveness to norepinephrine, arterial remodeling, and the effect of beta-blockade on cardiac hypertrophy

    Directory of Open Access Journals (Sweden)

    Walker LeeAnn

    2002-01-01

    Full Text Available Abstract Background Iron deficiency (ID results in ventricular hypertrophy, believed to involve sympathetic stimulation. We hypothesized that with ID 1 intravenous norepinephrine would alter heart rate (HR and contractility, 2 abdominal aorta would be larger and more distensible, and 3 the beta-blocker propanolol would reduce hypertrophy. Methods 1 30 CD rats were fed an ID or replete diet for 1 week or 1 month. Norepinephrine was infused via jugular vein; pressure was monitored at carotid artery. Saline infusions were used as a control. The pressure trace was analyzed for HR, contractility, systolic and diastolic pressures. 2 Abdominal aorta catheters inflated the aorta, while digital microscopic images were recorded at stepwise pressures to measure arterial diameter and distensibility. 3 An additional 10 rats (5 ID, 5 control were given a daily injection of propanolol or saline. After 1 month, the hearts were excised and weighed. Results Enhanced contractility, but not HR, was associated with ID hypertrophic hearts. Systolic and diastolic blood pressures were consistent with an increase in arterial diameter associated with ID. Aortic diameter at 100 mmHg and distensibility were increased with ID. Propanolol was associated with an increase in heart to body mass ratio. Conclusions ID cardiac hypertrophy results in an increased inotropic, but not chronotropic response to the sympathetic neurotransmitter, norepinephrine. Increased aortic diameter is consistent with a flow-dependent vascular remodeling; increased distensibility may reflect decreased vascular collagen content. The failure of propanolol to prevent hypertrophy suggests that ID hypertrophy is not mediated via beta-adrenergic neurotransmission.

  19. Estrogen receptor beta participate in the regulation of metabolizm of extracellular matrix in estrogen alpha negative breast cancer.

    Science.gov (United States)

    Leśniewska, Monika; Miltyk, Wojciech; Swiatecka, Jolanta; Tomaszewska, Małgorzata; Kuźmicki, Mariusz; Pałka, Jerzy; Wołczyński, Sławomir

    2009-01-01

    The biology of breast cancer is closely releted to sex steroid hormones. Estrogen receptor beta is overexpressed in around 70% breast cancer cases, referrd to as "ER positive". Estrogens bind to estrogen receptor and stimulate the transcription of genes involved in control of cell proliferation. Moreover, estrogens may induce growth factors and components of extracellular matrix and interact with them in a complex manner. Extracellular matrix and integrins play an important role in cell functions and their aberrant expressions are implicated in breast cancer development, invasion and metastasis. ER beta is certainly associated with more differentiated tumors, while evidence of role of ER beta is controversial. The highly invasive breast cancer ER beta negative cell line MDA-MB 231 can be the model of exam the role of ER beta in breast cancer. The aim of this study was to examine the role of activation of ER beta on the metabolism of the extracellular matrix and the expression of beta-1 integrin in the breast cancer cell line MDA-MB 231. The cells were exposed on the estradiol, tamoxifen, raloxifen and genisteina in dose dependent concentrations. To determine the relative rate of collagen syntesis we measured the time-dependent reduction of collagen-bound radioactivity after pulse-chase labeling with [3 H] prolina by Peterkofsky methods. The expression of beta-1 integrin was determine by Western blot analysis. The activity of MMP2 and 9 were measured using gelatin zymography with an image analysis system. Our data suggest on the role of estrogen receptor beta on the metabolism of extracellular matrix in the breast cancer line MDA - MB 231. Estradiol and SERMs regulate the expression of ECM proteins: collagen, integrins and enhance activity of metaloproteinases 2 and 9. PMID:20067880

  20. Estrogen receptor beta participate in the regulation of metabolizm of extracellular matrix in estrogen alpha negative breast cancer.

    Directory of Open Access Journals (Sweden)

    Mariusz Kuźmicki

    2010-01-01

    Full Text Available The biology of breast cancer is closely releted to sex steroid hormones. Estrogen receptor beta is overexpressed in around 70% breast cancer cases, referrd to as "ER positive". Estrogens bind to estrogen receptor and stimulate the transcription of genes involved in control of cell proliferation. Moreover, estrogens may induce growth factors and components of extracellular matrix and interact with them in a complex manner. Extracellular matrix and integrins play an important role in cell functions and their aberrant expressions are implicated in breast cancer development, invasion and metastasis. ER beta is certainly associated with more differentiated tumors, while evidence of role of ER beta is controversial. The highly invasive breast cancer ER beta negative cell line MDA-MB 231 can be the model of exam the role of ER beta in breast cancer. The aim of this study was to examine the role of activation of ER beta on the metabolism of the extracellular matrix and the expression of beta-1 integrin in the breast cancer cell line MDA-MB 231. The cells were exposed on the estradiol, tamoxifen, raloxifen and genisteina in dose dependent concentrations. To determine the relative rate of collagen syntesis we measured the time-dependent reduction of collagen-bound radioactivity after pulse-chase labeling with [3 H] prolina by Peterkofsky methods. The expression of beta-1 integrin was determine by Western blot analysis. The activity of MMP2 and 9 were measured using gelatin zymography with an image analysis system. Our data suggest on the role of estrogen receptor beta on the metabolism of extracellular matrix in the breast cancer line MDA - MB 231. Estradiol and SERMs regulate the expression of ECM proteins: collagen, integrins and enhance activity of metaloproteinases 2 and 9.

  1. Signal transduction in human pancreatic cancer: roles of transforming growth factor beta, somatostatin receptors, and other signal intermediates.

    Science.gov (United States)

    Li, Min; Becnel, Lauren S; Li, Wei; Fisher, William E; Chen, Changyi; Yao, Qizhi

    2005-01-01

    Pancreatic cancer is a devastating disease because of the lack of early detection markers and effective treatments. It is the fourth leading cause of cancer-related death in western countries, including the United States. The mechanisms of pancreatic cancer progression remain unknown. Transforming growth factor beta (TGF-beta), a multifunctional cytokine, regulates cell growth and differentiation in healthy tissues, yet fails to do so in pancreatic cancer. Alterations of the TGF-beta and TGF-beta receptor/Smad signal transduction pathway have been implicated in pancreatic cancer. Furthermore, both the TGF-beta receptor and Smad proteins interact with a variety of cellular signal pathways, such as the somatostatin receptors (SSTRs), ERK1/2, and Wnt signal transduction cascades. This suggests that pancreatic cancer is a multi-gene-controlled malignancy and that effective treatments for pancreatic cancer should be aimed at multiple targets. In this review, we summarized the major signal intermediates involved in pancreatic cancer signal transduction pathways and specifically discussed how alterations in the regulatory functions of TGF-beta and Smad proteins allow for pancreatic carcinogenesis. PMID:16314822

  2. Mu-opiate receptor and Beta-endorphin expression in nerve endings and keratinocytes in human skin.

    Science.gov (United States)

    Bigliardi-Qi, M; Sumanovski, L T; Büchner, S; Rufli, T; Bigliardi, P L

    2004-01-01

    We have previously shown that human epidermal keratinocytes express a functionally active micro-opiate receptor, which adds a new dimension to the recently developed research in neuroimmunodermatology and neurogenic inflammation in skin diseases. Human keratinocytes specifically bind and also produce beta-endorphin, the endogenous micro-opiate receptor ligand. Using confocal imaging microscopy, we could now demonstrate that micro-opiate receptors are not only expressed in keratinocytes, but also on unmyelinated peripheral nerve fibers in the dermis and epidermis. Some of the peripheral nerve fibers also express the ligand beta-endorphin. The keratinocytes positive for beta-endorphin staining are clustered around the terminal ends of the unmyelinated nerve fibers. Therefore the opiate receptor system seems to be crucial in the direct communication between nerves and skin. The keratinocytes can influence the unmyelinated nerve fibers in the epidermis directly via secreting beta-endorphin. On the other hand, nerve fibers can also secrete beta-endorphin and influence the migration, differentiation and probably also the cytokine production pattern of keratinocytes.

  3. Pharmacological blockade of either cannabinoid CB1 or CB2 receptors prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rat

    Science.gov (United States)

    Blanco-Calvo, Eduardo; Rivera, Patricia; Arrabal, Sergio; Vargas, Antonio; Pavón, Francisco Javier; Serrano, Antonia; Castilla-Ortega, Estela; Galeano, Pablo; Rubio, Leticia; Suárez, Juan; Rodriguez de Fonseca, Fernando

    2014-01-01

    Addiction to major drugs of abuse, such as cocaine, has recently been linked to alterations in adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulates this proliferative response as demonstrated by the finding that pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors not only modulates neurogenesis but also modulates cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation. To this end, we examined whether pharmacological blockade of either CB1 (Rimonabant, 3 mg/kg) or CB2 receptors (AM630, 3 mg/kg) would affect cell proliferation [the cells were labeled with 5-bromo-2′-deoxyuridine (BrdU)] in the subventricular zone (SVZ) of the lateral ventricle and the dentate subgranular zone (SGZ). Additionally, we measured cell apoptosis (as monitored by the expression of cleaved caspase-3) and glial activation [by analyzing the expression of glial fibrillary acidic protein (GFAP) and Iba-1] in the striatum and hippocampus during acute and repeated (4 days) cocaine administration (20 mg/kg). The results showed that acute cocaine exposure decreased the number of BrdU-immunoreactive (ir) cells in the SVZ and SGZ. In contrast, repeated cocaine exposure reduced the number of BrdU-ir cells only in the SVZ. Both acute and repeated cocaine exposure increased the number of cleaved caspase-3-, GFAP- and Iba1-ir cells in the hippocampus, and this effect was counteracted by AM630 or Rimonabant, which increased the number of BrdU-, GFAP-, and Iba1-ir cells in the hippocampus. These results indicate that the changes in neurogenic, apoptotic and gliotic processes that were produced by repeated cocaine administration were normalized by pharmacological blockade of CB1 and CB2. The restorative effects of cannabinoid receptor blockade on hippocampal cell proliferation were associated with the prevention of the induction of conditioned

  4. Pharmacological blockade of either cannabinoid CB1 or CB2 receptors prevents both cocaine-induced conditioned locomotion and cocaine-induced reduction of cell proliferation in the hippocampus of adult male rat.

    Science.gov (United States)

    Blanco-Calvo, Eduardo; Rivera, Patricia; Arrabal, Sergio; Vargas, Antonio; Pavón, Francisco Javier; Serrano, Antonia; Castilla-Ortega, Estela; Galeano, Pablo; Rubio, Leticia; Suárez, Juan; Rodriguez de Fonseca, Fernando

    2014-01-01

    Addiction to major drugs of abuse, such as cocaine, has recently been linked to alterations in adult neurogenesis in the hippocampus. The endogenous cannabinoid system modulates this proliferative response as demonstrated by the finding that pharmacological activation/blockade of cannabinoid CB1 and CB2 receptors not only modulates neurogenesis but also modulates cell death in the brain. In the present study, we evaluated whether the endogenous cannabinoid system affects cocaine-induced alterations in cell proliferation. To this end, we examined whether pharmacological blockade of either CB1 (Rimonabant, 3 mg/kg) or CB2 receptors (AM630, 3 mg/kg) would affect cell proliferation [the cells were labeled with 5-bromo-2'-deoxyuridine (BrdU)] in the subventricular zone (SVZ) of the lateral ventricle and the dentate subgranular zone (SGZ). Additionally, we measured cell apoptosis (as monitored by the expression of cleaved caspase-3) and glial activation [by analyzing the expression of glial fibrillary acidic protein (GFAP) and Iba-1] in the striatum and hippocampus during acute and repeated (4 days) cocaine administration (20 mg/kg). The results showed that acute cocaine exposure decreased the number of BrdU-immunoreactive (ir) cells in the SVZ and SGZ. In contrast, repeated cocaine exposure reduced the number of BrdU-ir cells only in the SVZ. Both acute and repeated cocaine exposure increased the number of cleaved caspase-3-, GFAP- and Iba1-ir cells in the hippocampus, and this effect was counteracted by AM630 or Rimonabant, which increased the number of BrdU-, GFAP-, and Iba1-ir cells in the hippocampus. These results indicate that the changes in neurogenic, apoptotic and gliotic processes that were produced by repeated cocaine administration were normalized by pharmacological blockade of CB1 and CB2. The restorative effects of cannabinoid receptor blockade on hippocampal cell proliferation were associated with the prevention of the induction of conditioned locomotion

  5. Relationship between Expression of beta-catenin and VEGFs(VEGFA,VEGF-C),VEGF Receptors-2(VEGFR-2)in Medulloblastoma

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hong-mei; ZHANG Xiong; LI Yu; MI Can

    2008-01-01

    Objective:To investigate the expression of beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGF receptor-2(VEGFR-2)protein in medulloblastoma.Methods:Immunohistochemical staining with SP method Was conducted to determine the expression of beta-eatenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 in 33 cases of medulloblastoma and 10 normal cerebellar tissues. Results:The expression rate of beta-catenin,and VEGFs (VEGF-A,VEGF-C)and VEGFR-2 in medulloblastoma were significantly higher than that in normal tissue.A significant positive correlation was found between beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 protein in medulloblastoma. Conclusion:There was a correlation between beta-catenin and VEGFs(VEGF-A,VEGF-C)and VEGFR-2 in medulloblastoma,which may play a role in the pathogenesis and development of medulloblastoma.

  6. Mechanisms of transcriptional activation of the mouse claudin-5 promoter by estrogen receptor alpha and beta.

    Science.gov (United States)

    Burek, Malgorzata; Steinberg, Katrin; Förster, Carola Y

    2014-07-01

    Claudin-5 is an integral membrane protein and a critical component of endothelial tight junctions that control paracellular permeability. Claudin-5 is expressed at high levels in the brain vascular endothelium. Estrogens have multiple effects on vascular physiology and function. The biological actions of estrogens are mediated by two different estrogen receptor (ER) subtypes, ER alpha and ER beta. Estrogens have beneficial effects in several vascular disorders. Recently we have cloned and characterized a murine claudin-5 promoter and demonstrated 17beta-estradiol (E2)-mediated regulation of claudin-5 in brain and heart microvascular endothelium on promoter, mRNA and protein level. Sequence analysis revealed a putative estrogen response element (ERE) and a putative Sp1 transcription factor binding site in the claudin-5 promoter. The aim of the present study was to further characterize the estrogen-responsive elements of claudin-5 promoter. First, we introduced point mutations in ERE or Sp1 site in -500/+111 or in Sp1 site of -268/+111 claudin-5 promoter construct, respectively. Basal and E2-mediated transcriptional activation of mutated constructs was abrogated in the luciferase reporter gene assay. Next, we examined whether estrogen receptor subtypes bind to the claudin-5 promoter region. For this purpose we performed chromatin immunoprecipitation assays using anti-estrogen receptor antibodies and cellular lysates of E2-treated endothelial cells followed by quantitative PCR analysis. We show enrichment of claudin-5 promoter fragments containing the ERE- and Sp1-binding site in immunoprecipitates after E2 treatment. Finally, in a gel mobility shift assay, we demonstrated DNA-protein interaction of both ER subtypes at ERE. In summary, this study provides evidence that both a non-consensus ERE and a Sp1 site in the claudin-5 promoter are functional and necessary for the basal and E2-mediated activation of the promoter.

  7. Coregulation of calcium channels and beta-adrenergic receptors in cultured chick embryo ventricular cells

    International Nuclear Information System (INIS)

    To examine mechanisms whereby the abundance of functional Ca channels may be regulated in excitable tissue, Ca channel number was estimated by binding of the dihydropyridine (DHP) antagonist 3H (+)PN200-110 to monolayers of intact myocytes from chick embryo ventricle. Beta adrenergic receptor properties were studied in cultured myocytes using [3H]CGP12177, an antagonist ligand. Physiological correlates for alterations in DHP binding site number included 45Ca uptake and contractile response to (+)BAYk 8644, a specific L-type Ca channel activator. All binding and physiological determinations were performed in similar intact cell preparations under identical conditions. 4-h exposure to 1 microM isoproterenol reduced cell surface beta-adrenergic receptor number from 44 +/- 3 to 17 +/- 2 fmol/mg (P less than 0.05); DHP binding sites declined in number from 113 +/- 25 to 73 +/- 30 fmol/mg (P less than 0.03). When protein kinase A was activated by a non-receptor-dependent mechanism, DHP binding declined similarly to 68% of control. Exposure to diltiazem, a Ca channel antagonist, for 18-24 h had no effect on number of DHP binding sites. After 4-h isoproterenol exposure, 45Ca uptake stimulated by BAYk 8644 declined from 3.3 +/- 0.2 nmol/mg to 2.9 +/- 0.3 nmol/mg (P less than 0.01) and BAYk 8644-stimulated increase in amplitude of contraction declined from 168 +/- 7 to 134 +/- 11% (P = 0.02). Thus, elevation of [cAMP] in myocytes is associated with a time-dependent decline in Ca channel abundance as estimated by DHP binding and a decline in physiological responses that are in part dependent on abundance of Ca channels. Binding of a directly acting Ca channel antagonist for 18-24 h does not modulate the number of DHP binding sites

  8. RT-PCR and Northern blot analysis in search for a putative Paramecium beta-adrenergic receptor.

    Science.gov (United States)

    Płatek, A; Wiejak, J; Wyroba, E

    1999-01-01

    RT-PCR and Northern blot analysis were performed in order to search for a putative beta-adrenergic receptor (beta-AR) in Paramecium using several beta2-adrenergic-specific molecular probes. Under strictly defined RT-PCR conditions DNA species of expected molecular size about 360 bp were generated with the primers corresponding to the universal mammalian beta2-AR sequence tagged sites (located within the 4th and the 6th transmembrane regions of the receptor). This RT-PCR product hybridized in Southern blot analysis with the oligonucleotide probe designed to the highly conservative beta2-AR region involved in G-proteins interaction and located within the amplified region. Northern hybridization was performed on Paramecium total RNA and mRNA with human beta2-AR cDNA and two oligonucleotide probes: the first included Phe 290 involved in agonist binding (Strader et al., 1995) and the second was the backward RT-PCR primer. All these probes revealed the presence of about 2 kb mRNA which is consistent with the size of beta2-AR transcripts found in higher eukaryotes.

  9. The androgen 5alpha-dihydrotestosterone and its metabolite 5alpha-androstan-3beta, 17beta-diol inhibit the hypothalamo-pituitary-adrenal response to stress by acting through estrogen receptor beta-expressing neurons in the hypothalamus.

    Science.gov (United States)

    Lund, Trent D; Hinds, Laura R; Handa, Robert J

    2006-02-01

    Estrogen receptor beta (ERbeta) and androgen receptor (AR) are found in high levels within populations of neurons in the hypothalamus. To determine whether AR or ERbeta plays a role in regulating hypothalamo-pituitary-adrenal (HPA) axis function by direct action on these neurons, we examined the effects of central implants of 17beta-estradiol (E2), 5alpha-dihydrotestosterone (DHT), the DHT metabolite 5alpha-androstan-3beta, 17beta-diol (3beta-diol), and several ER subtype-selective agonists on the corticosterone and adrenocorticotropin (ACTH) response to immobilization stress. In addition, activation of neurons in the paraventricular nucleus (PVN) was monitored by examining c-fos mRNA expression. Pellets containing these compounds were stereotaxically implanted near the PVN of gonadectomized male rats. Seven days later, animals were killed directly from their home cage (nonstressed) or were restrained for 30 min (stressed) before they were killed. Compared with controls, E2 and the ERalpha-selective agonists moxestrol and propyl-pyrazole-triol significantly increased the stress induced release of corticosterone and ACTH. In contrast, central administration of DHT, 3beta-diol, and the ERbeta-selective compound diarylpropionitrile significantly decreased the corticosterone and ACTH response to immobilization. Cotreatment with the ER antagonist tamoxifen completely blocked the effects of 3beta-diol and partially blocked the effect of DHT, whereas the AR antagonist flutamide had no effect. Moreover, DHT, 3beta-diol, and diarylpropionitrile treatment significantly decreased restraint-induced c-fos mRNA expression in the PVN. Together, these studies indicate that the inhibitory effects of DHT on HPA axis activity may be in part mediated via its conversion to 3beta-diol and subsequent binding to ERbeta. PMID:16452668

  10. Activation of transmembrane bile acid receptor TGR5 stimulates insulin secretion in pancreatic {beta} cells

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Divya P.; Rajagopal, Senthilkumar; Mahavadi, Sunila [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Mirshahi, Faridoddin [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Grider, John R. [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Murthy, Karnam S., E-mail: skarnam@vcu.edu [Department of Physiology and Biophysics, Virginia Commonwealth University School of Medicine, Richmond, VA (United States); Sanyal, Arun J., E-mail: asanyal@mcvh-vcu.edu [Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, VA (United States)

    2012-10-26

    Highlights: Black-Right-Pointing-Pointer G protein coupled receptor TGR5 is expressed in mouse and human islets. Black-Right-Pointing-Pointer TGR5 is coupled to activation of Gs and Ca{sup 2+} release via cAMP/Epac/PLC-{epsilon} pathway. Black-Right-Pointing-Pointer Activation of TGR5 by bile salts and selective ligands causes insulin secretion. Black-Right-Pointing-Pointer TGR5 could be a potential therapeutic target to treat diabetes. -- Abstract: Bile acids act as signaling molecules and stimulate the G protein coupled receptor, TGR5, in addition to nuclear farnesoid X receptor to regulate lipid, glucose and energy metabolism. Bile acid induced activation of TGR5 in the enteroendocrine cells promotes glucagon like peptide-1 (GLP-1) release, which has insulinotropic effect in the pancreatic {beta} cells. In the present study, we have identified the expression of TGR5 in pancreatic {beta} cell line MIN6 and also in mouse and human pancreatic islets. TGR5 selective ligands, oleanolic acid (OA) and INT-777 selectively activated G{alpha}{sub s} and caused an increase in intracellular cAMP and Ca{sup 2+}. OA and INT-777 also increased phosphoinositide (PI) hydrolysis and the increase was blocked by NF449 (a selective G{alpha}{sub s} inhibitor) or (U73122) (PI hydrolysis inhibitor). OA, INT-777 and lithocholic acid increased insulin release in MIN6 and human islets and the increase was inhibited by treatment with NF449, (U73122) or BAPTA-AM (chelator of calcium), but not with myristoylated PKI (PKA inhibitor), suggesting that the release is dependent on G{sub s}/cAMP/Ca{sup 2+} pathway. 8-pCPT-2 Prime -O-Me-cAMP, a cAMP analog, which activates Epac, but not PKA also stimulated PI hydrolysis. In conclusion, our study demonstrates that the TGR5 expressed in the pancreatic {beta} cells regulates insulin secretion and highlights the importance of ongoing therapeutic strategies targeting TGR5 in the control of glucose homeostasis.

  11. Reduced number of alpha- and beta-adrenergic receptors in the myocardium of rats exposed to tobacco smoke

    Energy Technology Data Exchange (ETDEWEB)

    Larue, D.; Kato, G.

    1981-04-09

    The concentration of alpha- and beta-adrenergic receptors--as measured by specific (/sup 3/H)WB-4101 and (-)-(/sup 3/H)dihydroalprenolol binding--was diminished by 60% below control values in the hearts of rats exposed to tobacco smoke. These changes in receptor numbers took place almost immediately after tobacco smoke exposure and were rapidly reversible after termination of the exposure. The dissociation constant, KD, for (/sup 3/H)WB-4101 was identical in exposed (KD . 0.34 +/- 0.09 nM) and control (KD . 0.35 +/- 0.07 nM) hearts but was significantly different in the case of (-)-(3H)dihydroalprenolol binding (exposed, KD . 2.83 +/- 0.30 mM vs. control KD . 5.22 +/- 0.61 nM). For beta-receptor binding there was no significant difference between exposed and control animals in the Ki values for (-)-epinephrine, (-)-norepinephrine, (-)-alprenolol, (+/-)-propranolol or timolol. (-)-Isoproterenol, however, was found to bind with lower affinity in exposed compared with control hearts. For alpha-receptor binding there was no significant difference between control and 'smoked' animals in the Ki values for (-)-epinephrine, (-0)-norepinephrine or phentolamine. The decrease in alpha- and beta-adrenergic receptor concentration may be related to the phenomenon of receptor desensitization resulting from a release of catecholamines in rats exposed to tobacco smoke.

  12. An LRP5 receptor with internal deletion in hyperparathyroid tumors with implications for deregulated WNT/beta-catenin signaling.

    Directory of Open Access Journals (Sweden)

    Peyman Björklund

    2007-11-01

    Full Text Available BACKGROUND: Hyperparathyroidism (HPT is a common endocrine disorder with incompletely understood etiology, characterized by enlarged hyperactive parathyroid glands and increased serum concentrations of parathyroid hormone and ionized calcium. We have recently reported activation of the Wnt signaling pathway by accumulation of beta-catenin in all analyzed parathyroid tumors from patients with primary HPT (pHPT and in hyperplastic parathyroid glands from patients with uremia secondary to HPT (sHPT. Mechanisms that may account for this activation have not been identified, except for a few cases of beta-catenin (CTNNB1 stabilizing mutation in pHPT tumors. METHODS AND FINDINGS: Reverse transcription PCR and Western blot analysis showed expression of an aberrantly spliced internally truncated WNT coreceptor low-density lipoprotein receptor-related protein 5 (LRP5 in 32 out of 37 pHPT tumors (86% and 20 out of 20 sHPT tumors (100%. Stabilizing mutation of CTNNB1 and expression of the internally truncated LRP5 receptor was mutually exclusive. Expression of the truncated LRP5 receptor was required to maintain the nonphosphorylated active beta-catenin level, transcription activity of beta-catenin, MYC expression, parathyroid cell growth in vitro, and parathyroid tumor growth in a xenograft severe combined immunodeficiency (SCID mouse model. WNT3 ligand and the internally truncated LRP5 receptor strongly activated transcription, and the internally truncated LRP5 receptor was insensitive to inhibition by DKK1. CONCLUSIONS: The internally truncated LRP5 receptor is strongly implicated in deregulated activation of the WNT/beta-catenin signaling pathway in hyperparathyroid tumors, and presents a potential target for therapeutic intervention.

  13. Retinoic acid receptor beta2 promotes functional regeneration of sensory axons in the spinal cord.

    Science.gov (United States)

    Wong, Liang-Fong; Yip, Ping K; Battaglia, Anna; Grist, John; Corcoran, Jonathan; Maden, Malcolm; Azzouz, Mimoun; Kingsman, Susan M; Kingsman, Alan J; Mazarakis, Nicholas D; McMahon, Stephen B

    2006-02-01

    The embryonic CNS readily undergoes regeneration, unlike the adult CNS, which has limited axonal repair after injury. Here we tested the hypothesis that retinoic acid receptor beta2 (RARbeta2), critical in development for neuronal growth, may enable adult neurons to grow in an inhibitory environment. Overexpression of RARbeta2 in adult rat dorsal root ganglion cultures increased intracellular levels of cyclic AMP and stimulated neurite outgrowth. Stable RARbeta2 expression in DRG neurons in vitro and in vivo enabled their axons to regenerate across the inhibitory dorsal root entry zone and project into the gray matter of the spinal cord. The regenerated neurons enhanced second-order neuronal activity in the spinal cord, and RARbeta2-treated rats showed highly significant improvement in sensorimotor tasks. These findings show that RARbeta2 induces axonal regeneration programs within injured neurons and may thus offer new therapeutic opportunities for CNS regeneration. PMID:16388307

  14. Design and synthesis of carborane-containing estrogen receptor-beta (ERβ)-selective ligands.

    Science.gov (United States)

    Ohta, Kiminori; Ogawa, Takumi; Oda, Akifumi; Kaise, Asako; Endo, Yasuyuki

    2015-10-01

    Candidates for highly selective estrogen receptor-beta (ERβ) ligands (6a-c, 7a-c, 8a and 8b) were designed and synthesized based on carborane-containing ER ligands 1 and 2 as lead compounds. Among them, p-carboranylcyclohexanol derivatives 8a and 8b exhibited high ERβ selectivity in competitive binding assay: for example, 8a showed 56-fold selectivity for ERβ over ERα. Docking studies of 8a and 8b with the ERα and ERβ ligand-binding domains (LBDs) suggested that the p-carborane cage of the ligands is located close to key amino acid residues that influence ER-subtype selectivity, that is, Leu384 in the ERα LBD and Met336 in the ERβ LBD. The p-carborane cage in 8a and 8b appears to play a crucial role in the increased ERβ selectivity. PMID:26298498

  15. Genomic organization of the mouse peroxisome proliferator-activated receptor beta/delta gene

    DEFF Research Database (Denmark)

    Larsen, Leif K; Amri, Ez-Zoubir; Mandrup, Susanne;

    2002-01-01

    Peroxisome proliferator-activated receptor (PPAR) beta/delta is ubiquitously expressed, but the level of expression differs markedly between different cell types. In order to determine the molecular mechanisms governing PPARbeta/delta gene expression, we have isolated and characterized the mouse...... gene encoding PPARbeta/delta. The gene spans approx. 41 kb and comprises 11 exons of which the six exons located in the 3'-end of the gene are included in all transcripts. Primer-extension and 5'-rapid amplification of cDNA ends experiments revealed the presence of multiple transcription start points...... and splice variants, originating from the use of at least four different promoters. One of these transcription start points was found to be used predominantly in all tissues examined. Initiation from this major transcription start point gives rise to a transcript with a 548 nt 5'-untranslated leader...

  16. GABA{sub A} receptor beta 3 subunit gene is possibly paternally imprinted in humans

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-02-15

    As the gene for GABA{sub A} receptor beta 3 subunit (GABRB3) is encompassed by a small molecular deletion in chromosome 15q11-q13, which is the critical region for Angelman syndrome(AS), the GABRB3 gene could be a candidate gene for AS. The abnormal phenotype of AS is manifested only when the deletion is inherited from the mother, not from the father. Therefore, a candidate gene for AS should be paternally imprinted. Although it was reported that the GABRB3 gene was expressed equally from either the maternal or paternal chromosome in mouse brain (i.e., not imprinted), it is well known that imprinting shows tissue specificity, and it remains to be determined if all genes imprinted in the mouse are also imprinted in humans. 4 refs., 1 fig.

  17. Beta3 adrenergic receptor is involved in vascular injury in deoxycorticosterone acetate-salt hypertensive mice.

    Science.gov (United States)

    Sheng, Li-Juan; Ruan, Cheng-Chao; Ma, Yu; Chen, Dong-Rui; Kong, Ling-Ran; Zhu, Ding-Liang; Gao, Ping-Jin

    2016-03-01

    Beta3 adrenergic receptor (ADRB3) mediates vessel relaxation in the endothelium while it modulates lipolysis in the adipose tissue. However, the function and regulation mechanism of ADRB3 in the perivascular adipose tissue (PVAT), especially in hypertension, is still unclear. We show that ADRB3 protein is upregulated in the PVAT of deoxycorticosterone acetate-salt (DOCA-salt) hypertensive mice, with the characteristics of PVAT browning and increased uncoupling protein 1 (UCP1) expression. Inhibition of ADRB3 with selective antagonist SR59230A caused serious vascular injury in vivo, even though UCP1 expression was downregulated. ADRB3 protein was regulated by let-7b, which was decreased in the PVAT of the DOCA-salt group. These data reveal that ADRB3 in PVAT contributes to vascular function in the progression of hypertension. PMID:26910302

  18. AVPV neurons containing estrogen receptor-beta in adult male rats are influenced by soy isoflavones

    Directory of Open Access Journals (Sweden)

    Bu Lihong

    2007-02-01

    Full Text Available Abstract Background Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. It is known that 17beta-estradiol induces apoptosis in anteroventral periventricular nucleus (AVPV in rat brain. Also, there is evidence that consumption of soy isoflavones reduces the volume of AVPV in male rats. Therefore, in this study, we examined the influence of dietary soy isoflavones on apoptosis in AVPV of 150 day-old male rats fed either a soy isoflavone-free diet (Phyto-free or a soy isoflavone-rich diet (Phyto-600. Results The occurrence of apoptosis in AVPV was examined by TUNEL staining. The incidence of apoptosis was about 10 times higher in the Phyto-600 group (33.1 ± 1.7% than in the Phyto-free group (3.6 ± 1.0%. Furthermore, these apoptotic cells were identified as neurons by dual immunofluorescent staining of GFAP and NeuN as markers of astrocytes and neurons, respectively. Then the dopaminergic neurons in AVPV were detected by immunohistochemistry staining of tyrosine hydroxylase (TH. No significant difference in the number of TH neurons was observed between the diet treatment groups. When estrogen receptor (ER alpha and beta were examined by immunohistochemistry, we observed a 22% reduction of ERbeta-positive cell numbers in AVPV with consumption of soy isoflavones, whereas no significant change in ERalpha-positive cell numbers was detected. Furthermore, almost all the apoptotic cells were ERbeta-immunoreactive (ir, but not ERalpha-ir. Last, subcutaneous injections of equol (a major isoflavone metabolite that accounts for approximately 70–90% of the total circulating plasma isoflavone levels did not alter the volume of AVPV in adult male rats. Conclusion In summary, these findings provide direct evidence that consumption of soy isoflavones, but not the exposure to equol, influences the loss of ERbeta-containing neurons in male AVPV.

  19. In vivo occupancy of female rat brain estrogen receptors by 17beta-estradiol and tamoxifen.

    Science.gov (United States)

    Pareto, D; Alvarado, M; Hanrahan, S M; Biegon, A

    2004-11-01

    Estrogens or antiestrogens are currently used by millions of women, but the interaction of these hormonal agents with brain estrogen receptors (ER) in vivo has not been characterized to date. Our goal was to assess, in vivo, the extent and regional distribution of brain ER occupancy in rats chronically exposed to 17beta-estradiol (E(2)) or tamoxifen (TAM). For that purpose, female ovariectomized Sprague-Dawley rats were implanted with subcutaneous pellets containing either placebo (OVX), E(2), or TAM for 3 weeks. ER occupancy in grossly dissected regions was quantified with 16alpha-[(18)F]fluoroestradiol ([(18)F]FES). Both E(2) and TAM produced significant decreases in radioligand uptake in the brain although the effect of E(2) was larger and more widespread than the effect of TAM. Detailed regional analysis of the interaction was then undertaken using a radioiodinated ligand, 11beta-methoxy-16alpha-[(125)I]iodo-estradiol ([(125)I]MIE(2)), and quantitative ex vivo autoradiography. E(2) treatment resulted in near-complete (86.6 +/- 17.5%) inhibition of radioligand accumulation throughout the brain, while ER occupancy in the TAM group showed a marked regional distribution such that percentage inhibition ranged from 40.5 +/- 15.6 in the ventrolateral part of the ventromedial hypothalamic nucleus to 84.6 +/- 4.5 in the cortical amygdala. These results show that exposure to pharmacologically relevant levels of TAM produces a variable, region-specific pattern of brain ER occupancy, which may be influenced by the regional proportion of ER receptor subtypes. These findings may partially explain the highly variable and region-specific effects observed in neurochemical, metabolic, and functional studies of the effects of TAM in the brain of experimental animals as well as human subjects.

  20. Nuclear orphan receptor TLX affects gene expression, proliferation and cell apoptosis in beta cells.

    Science.gov (United States)

    Shi, Xiaoli; Xiong, Xiaokan; Dai, Zhe; Deng, Haohua; Sun, Li; Hu, Xuemei; Zhou, Feng; Xu, Yancheng

    Nuclear orphan receptor TLX is an essential regulator of the growth of neural stem cells. However, its exact function in pancreatic islet cells is still unknown. In the present study, gene expression profiling analysis revealed that overexpression of TLX in beta cell line MIN6 causes suppression of 176 genes and upregulation of 49 genes, including a cadre of cell cycle, cell proliferation and cell death control genes, such as Btg2, Ddit3 and Gadd45a. We next examined the effects of TLX overexpression on proliferation, apoptosis and insulin secretion in MIN6 cells. Proliferation analysis using EdU assay showed that overexpression of TLX increased percentage of EdU-positive cells. Cell cycle and apoptosis analysis revealed that overexpression of TLX in MIN6 cells resulted in higher percentage of cells exiting G1 into S-phase, and a 58.8% decrease of cell apoptosis induced by 0.5 mM palmitate. Moreover, TLX overexpression did not cause impairment of insulin secretion. Together, we conclude that TLX is among factors capable of controlling beta cell proliferation and survival, which may serve as a target for the development of novel therapies for diabetes.

  1. INTERACTION OF PAH-RELATED COMPOUNDS WITH THE ALPHA AND BETA ISOFORMS OF ESTROGEN RECEPTOR. (R826192)

    Science.gov (United States)

    The ability of several 4- and 5-ring polycyclic aromatic hydrocarbons (PAHs), heterocyclic PAHs, and their monohydroxy derivatives to interact with the estrogen receptor (ER) alpha and beta isoforms was examined. Only compounds possessing a hydroxyl group were able to compete wit...

  2. Vertebral Artery Aneurysm Mimicking as Left Subclavian Artery Aneurysm in a Patient with Transforming Growth Factor Beta Receptor II Mutation.

    Science.gov (United States)

    Afifi, Rana O; Dhillon, Baltej Singh; Sandhu, Harleen K; Charlton-Ouw, Kristofer M; Estrera, Anthony L; Azizzadeh, Ali

    2015-10-01

    We report successful endovascular repair of a left vertebral artery aneurysm in a patient with transforming growth factor beta receptor II mutation. The patient was initially diagnosed with a left subclavian artery aneurysm on computed tomography angiography. The patient consented to publication of this report.

  3. Polymorphisms of innate pattern recognition receptors, response to interferon-beta and development of neutralizing antibodies in multiple sclerosis patients

    DEFF Research Database (Denmark)

    Enevold, Christian; Oturai, Annette Bang; Sørensen, Per Soelberg;

    2010-01-01

    Interferon-beta therapy of patients with relapsing-remitting multiple sclerosis involves repeated 'immunizations' with exogenous protein solutions. Innate pattern recognition receptors play an important role in immune responses towards foreign substances and may thus be related to treatment outcome....

  4. Disappearance of beta(2)-adrenergic receptors on astrocytes in canine distemper encephalitis : possible implications for the pathogenesis of multiple sclerosis

    NARCIS (Netherlands)

    De Keyser, J; Wilczak, N; Zurbriggen, A

    2001-01-01

    It has been reported that astrocytes in the white matter of patients with multiple sclerosis (MS) lack beta (2)-adrenergic receptors. This abnormality might explain why astrocytes in active MS plaques aberrantly express major histocompatibility (MHC) class II molecules, which play an important role

  5. How Can 1+1=3? beta(2)-Adrenergic and Glucocorticoid Receptor Agonist Synergism in Obstructive Airway Diseases

    NARCIS (Netherlands)

    Schmidt, Martina; Michel, Martin C.

    2011-01-01

    For a long time it was believed that beta(2)-adrenergic receptor agonists used in the treatment of obstructive airway diseases worked primarily on airway smooth muscle cells, causing relaxation, whereas glucocorticoids primarily improved airway function via their anti-inflammatory action, indicating

  6. Platelet-Derived Growth Factor Receptor Beta Serum Concentrations during First-Line Therapy in Ovarian Cancer

    NARCIS (Netherlands)

    Mathey, Sabrina; Graeser, Monika Karla; Eulenburg, Christine Zu; Woelber, Linn; Trillsch, Fabian; Jaenicke, Fritz; Mueller, Volkmar; Milde-Langosch, Karin; Mahner, Sven

    2013-01-01

    Objectives: Angiogenesis plays an important role in ovarian cancer. The interaction of platelet-derived growth factor receptor-beta (PDGFR-P) with vascular endothelial growth factor (VEGF) in the process of angiogenesis may represent an essential feature in the progression of the disease. Methods: P

  7. Selective suppression of chemokine receptor CXCR3 expression by interferon-beta1a in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Sellebjerg, F

    2002-01-01

    We studied the expression of chemokine receptors CCR1, CCR2, CCR3, CCR5, and CXCR3 on CD4 and CD8 positive T cells, and on CD14 positive monocytes in blood from 10 patients with relapsing-remitting multiple sclerosis (MS) at initiation of interferon (IFN)-beta treatment, after 1 month and after 3...

  8. Family-based association analysis of beta(2)-adrenergic receptor polymorphisms in the Childhood Asthma Management Program

    NARCIS (Netherlands)

    Silverman, EK; Kwiatkowski, DJ; Sylvia, JS; Lazarus, R; Drazen, JM; Lange, C; Laird, NM; Weiss, ST

    2003-01-01

    Background: beta(2)-Adrenergic receptor (B2AR) polymorphisms have been associated with a variety of asthma-related phenotypes, but association results have been inconsistent across different studies. Objective: We sought to apply family-based association methods to individual single nucleotide polym

  9. Internalization of the human CRF receptor 1 is independent of classical phosphorylation sites and of beta-arrestin 1 recruitment

    DEFF Research Database (Denmark)

    Rasmussen, Trine N; Novak, Ivana; Nielsen, Søren M

    2004-01-01

    . In the present study, agonist-induced internalization of CRFR1 in HEK293 cells was visualized by confocal microscopy and quantified using the radioligand 125I-labelled sauvagine. Recruitment of beta-arrestin 1 in response to receptor activation was demonstrated by confocal microscopy. The extent of 125I...

  10. Deletion of angiotensin II type 2 receptor accelerates adipogenesis in murine mesenchymal stem cells via Wnt10b/beta-catenin signaling.

    Science.gov (United States)

    Matsushita, Kenichi; Wu, Yaojiong; Pratt, Richard E; Dzau, Victor J

    2016-08-01

    Recent evidence suggests that the renin-angiotensin system (RAS) has a vital role in adipocyte biology and the pathophysiology of metabolic syndrome. Obesity is the main culprit of metabolic syndrome; and mesenchymal stem cells (MSCs) have been forwarded as a major source of adipocyte generation. Previously, we reported that MSCs have a local RAS and that pharmacological blockade of angiotensin II type 2 receptor (AT2R) promotes adipogenesis in human MSCs. However, the definitive roles of AT2R and how AT2R functions in adipogenesis remains unknown. To this end, we employed AT2R-null murine MSCs to characterize how AT2R affects the differentiation of MSCs into adipocytes. Murine MSCs were isolated from AT2R-null mice and wild-type littermates, grown to confluency, and then differentiated into adipocytes. Adipogenesis was quantitated by assessing the lipid droplet accumulation. Using the lipophilic fluorescent dye, the AT2R-null cells showed significantly increased total fluorescence (261.6±49.6% vs littermate) on day 7. Oil red O staining followed by extraction of the absorbed dye and measurement of the absorbance on day 14 also exhibited significantly increased lipid droplet accumulation in the AT2R-null cells (202.7±14.1% vs littermate). We also examined the expression of adipogenic marker genes by quantitative RT-PCR. The AT2R-null group exhibited significantly increased expression of PPAR-gamma, fatty acid synthase, and adiponectin (vs littermate). We further examined the role of Wnt10b/beta-catenin signaling, which reportedly has an important inhibitory role in adipogenesis. The AT2R-null group exhibited significantly decreased Wnt10b expression accompanied by decreased beta-catenin (vs littermate). Our results thus revealed that the AT2R inhibits adipogenic differentiation in murine MSCs. Moreover, this inhibitory effect is associated with Wnt10b/beta-catenin signaling. These results provide important insights into the pathophysiology of obesity and obesity

  11. High-resolution crystal structure of an engineered human beta2-adrenergic G protein-coupled receptor

    DEFF Research Database (Denmark)

    Cherezov, Vadim; Rosenbaum, Daniel M; Hanson, Michael A;

    2007-01-01

    Heterotrimeric guanine nucleotide-binding protein (G protein)-coupled receptors constitute the largest family of eukaryotic signal transduction proteins that communicate across the membrane. We report the crystal structure of a human beta2-adrenergic receptor-T4 lysozyme fusion protein bound...... to the partial inverse agonist carazolol at 2.4 angstrom resolution. The structure provides a high-resolution view of a human G protein-coupled receptor bound to a diffusible ligand. Ligand-binding site accessibility is enabled by the second extracellular loop, which is held out of the binding cavity by a pair...

  12. Random length assortment of human and mouse T cell receptor for antigen alpha and beta chain CDR3.

    Science.gov (United States)

    Johnson, G; Wu, T T

    1999-10-01

    In view of the recently determined three-dimensional structures of complexes formed by the T cell receptor for antigen (TCR), the processed peptide and the MHC class I molecule, it is expected that the combined configuration formed by the third complementarity determining regions (CDR3) of TCR alpha and beta chains will be very restricted in size and shape due to the limited length variations of the processed peptides. Thus, the combined TCR alpha and beta chain CDR3 lengths should have a fairly narrow distribution. This feature can be due to the selective association of long alpha chain CDR3 with short beta chain CDR3 and vice versa or due to random assortment of alpha and beta chain CDR3 of even narrower length distribution. Based on existing translated amino acid sequence data, it has been found that the latter mechanism is responsible.

  13. Platelet-derived growth factor receptor beta is critical for zebrafish intersegmental vessel formation.

    Directory of Open Access Journals (Sweden)

    Katie M Wiens

    Full Text Available BACKGROUND: Platelet-derived growth factor receptor beta (PDGFRbeta is a tyrosine kinase receptor known to affect vascular development. The zebrafish is an excellent model to study specific regulators of vascular development, yet the role of PDGF signaling has not been determined in early zebrafish embryos. Furthermore, vascular mural cells, in which PDGFRbeta functions cell autonomously in other systems, have not been identified in zebrafish embryos younger than 72 hours post fertilization. METHODOLOGY/PRINCIPAL FINDINGS: In order to investigate the role of PDGFRbeta in zebrafish vascular development, we cloned the highly conserved zebrafish homolog of PDGFRbeta. We found that pdgfrbeta is expressed in the hypochord, a developmental structure that is immediately dorsal to the dorsal aorta and potentially regulates blood vessel development in the zebrafish. Using a PDGFR tyrosine kinase inhibitor, a morpholino oligonucleotide specific to PDGFRbeta, and a dominant negative PDGFRbeta transgenic line, we found that PDGFRbeta is necessary for angiogenesis of the intersegmental vessels. SIGNIFICANCE/CONCLUSION: Our data provide the first evidence that PDGFRbeta signaling is required for zebrafish angiogenesis. We propose a novel mechanism for zebrafish PDGFRbeta signaling that regulates vascular angiogenesis in the absence of mural cells.

  14. A liver X receptor (LXR)-{beta} alternative splicing variant (LXRBSV) acts as an RNA co-activator of LXR-{beta}

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Koshi, E-mail: khashi@med.gunma-u.ac.jp [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan); Ishida, Emi; Matsumoto, Shunichi; Shibusawa, Nobuyuki; Okada, Shuichi [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan); Monden, Tsuyoshi [Department of Endocrinology and Metabolism, Dokkyo Medical College, Mibu, Tochigi (Japan); Satoh, Tetsurou; Yamada, Masanobu; Mori, Masatomo [Department of Medicine and Molecular Science, Graduate School of Medicine, Gunma University, Maebashi, Gunma 371-8511 (Japan)

    2009-12-25

    We report the isolation and functional characterization of a novel transcriptional co-activator, termed LXRBSV. LXRBSV is an alternative splicing variant of liver X receptor (LXR)-{beta} LXRBSV has an intronic sequence between exons 2 and 3 in the mouse LXR-{beta} gene. The LXRBSV gene is expressed in various tissues including the liver and brain. We sub-cloned LXRBSV into pSG5, a mammalian expression vector, and LXRBSV in pSG5 augmented human Sterol Response Element Binding Protein (SREBP)-1c promoter activity in HepG2 cells in a ligand (TO901317) dependent manner. The transactivation mediated by LXRBSV is selective for LXR-{beta}. The LXRBSV protein was deduced to be 64 amino acids in length; however, a GAL4-LXRBSV fusion protein was not able to induce transactivation. Serial deletion constructs of LXRBSV demonstrated that the intronic sequence inserted in LXRBSV is required for its transactivation activity. An ATG mutant of LXRBSV was able to induce transactivation as wild type. Furthermore, LXRBSV functions in the presence of cycloheximide. Taken together, we have concluded that LXRBSV acts as an RNA transcript not as a protein. In the current study, we have demonstrated for the first time that an alternative splicing variant of a nuclear receptor acts as an RNA co-activator.

  15. Generation of an estrogen receptor beta-iCre knock-in mouse.

    Science.gov (United States)

    Cacioppo, Joseph A; Koo, Yongbum; Lin, Po-Ching Patrick; Osmulski, Sarah A; Ko, Chunjoo D; Ko, CheMyong

    2016-01-01

    A novel knock-in mouse that expresses codon-improved Cre recombinase (iCre) under regulation of the estrogen receptor beta (Esr2) promoter was developed for conditional deletion of genes and for the spatial and/or temporal localization of Esr2 expression. ESR2 is one of two classical nuclear estrogen receptors and displays a spatiotemporal expression pattern and functions that are different from the other estrogen receptor, ESR1. A cassette was constructed that contained iCre, a polyadenylation sequence, and a neomycin selection marker. This construct was used to insert iCre in front of the endogenous start codon of the Esr2 gene of a C57BL/6J embryonic stem cell line via homologous recombination. Resulting Esr2-iCre mice were bred with ROSA26-lacZ and Ai9-RFP reporter mice to visualize cells of functional iCre expression. Strong expression was observed in the ovary, the pituitary, the interstitium of the testes, the head and tail but not body of the epididymis, skeletal muscle, the coagulation gland (anterior prostate), the lung, and the preputial gland. Additional diffuse or patchy expression was observed in the cerebrum, the hypothalamus, the heart, the adrenal gland, the colon, the bladder, and the pads of the paws. Overall, Esr2-iCre mice will serve as a novel line for conditionally ablating genes in Esr2-expressing tissues, identifying novel Esr2-expressing cells, and differentiating the functions of ESR2 and ESR1.

  16. Recessive and dominant mutations in retinoic acid receptor beta in cases with microphthalmia and diaphragmatic hernia.

    Science.gov (United States)

    Srour, Myriam; Chitayat, David; Caron, Véronique; Chassaing, Nicolas; Bitoun, Pierre; Patry, Lysanne; Cordier, Marie-Pierre; Capo-Chichi, José-Mario; Francannet, Christine; Calvas, Patrick; Ragge, Nicola; Dobrzeniecka, Sylvia; Hamdan, Fadi F; Rouleau, Guy A; Tremblay, André; Michaud, Jacques L

    2013-10-01

    Anophthalmia and/or microphthalmia, pulmonary hypoplasia, diaphragmatic hernia, and cardiac defects are the main features of PDAC syndrome. Recessive mutations in STRA6, encoding a membrane receptor for the retinol-binding protein, have been identified in some cases with PDAC syndrome, although many cases have remained unexplained. Using whole-exome sequencing, we found that two PDAC-syndrome-affected siblings, but not their unaffected sibling, were compound heterozygous for nonsense (c.355C>T [p.Arg119(∗)]) and frameshift (c.1201_1202insCT [p.Ile403Serfs(∗)15]) mutations in retinoic acid receptor beta (RARB). Transfection studies showed that p.Arg119(∗) and p.Ile403Serfs(∗)15 altered RARB had no transcriptional activity in response to ligands, confirming that the mutations induced a loss of function. We then sequenced RARB in 15 subjects with anophthalmia and/or microphthalmia and at least one other feature of PDAC syndrome. Surprisingly, three unrelated subjects with microphthalmia and diaphragmatic hernia showed de novo missense mutations affecting the same codon; two of the subjects had the c.1159C>T (Arg387Cys) mutation, whereas the other one carried the c.1159C>A (p.Arg387Ser) mutation. We found that compared to the wild-type receptor, p.Arg387Ser and p.Arg387Cys altered RARB induced a 2- to 3-fold increase in transcriptional activity in response to retinoic acid ligands, suggesting a gain-of-function mechanism. Our study thus suggests that both recessive and dominant mutations in RARB cause anophthalmia and/or microphthalmia and diaphragmatic hernia, providing further evidence of the crucial role of the retinoic acid pathway during eye development and organogenesis.

  17. PGC-1{beta} regulates mouse carnitine-acylcarnitine translocase through estrogen-related receptor {alpha}

    Energy Technology Data Exchange (ETDEWEB)

    Gacias, Mar; Perez-Marti, Albert; Pujol-Vidal, Magdalena; Marrero, Pedro F. [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Haro, Diego, E-mail: dharo@ub.edu [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain); Relat, Joana [Department of Biochemistry and Molecular Biology, School of Pharmacy and the Institute of Biomedicine of the University of Barcelona (IBUB) (Spain)

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer The Cact gene is induced in mouse skeletal muscle after 24 h of fasting. Black-Right-Pointing-Pointer The Cact gene contains a functional consensus sequence for ERR. Black-Right-Pointing-Pointer This sequence binds ERR{alpha} both in vivo and in vitro. Black-Right-Pointing-Pointer This ERRE is required for the activation of Cact expression by the PGC-1/ERR axis. Black-Right-Pointing-Pointer Our results add Cact as a genuine gene target of these transcriptional regulators. -- Abstract: Carnitine/acylcarnitine translocase (CACT) is a mitochondrial-membrane carrier proteins that mediates the transport of acylcarnitines into the mitochondrial matrix for their oxidation by the mitochondrial fatty acid-oxidation pathway. CACT deficiency causes a variety of pathological conditions, such as hypoketotic hypoglycemia, cardiac arrest, hepatomegaly, hepatic dysfunction and muscle weakness, and it can be fatal in newborns and infants. Here we report that expression of the Cact gene is induced in mouse skeletal muscle after 24 h of fasting. To gain insight into the control of Cact gene expression, we examine the transcriptional regulation of the mouse Cact gene. We show that the 5 Prime -flanking region of this gene is transcriptionally active and contains a consensus sequence for the estrogen-related receptor (ERR), a member of the nuclear receptor family of transcription factors. This sequence binds ERR{alpha}in vivo and in vitro and is required for the activation of Cact expression by the peroxisome proliferator-activated receptor gamma coactivator (PGC)-1/ERR axis. We also demonstrate that XTC790, the inverse agonist of ERR{alpha}, specifically blocks Cact activation by PGC-1{beta} in C2C12 cells.

  18. NMDA-receptor activation but not ion flux is required for amyloid-beta induced synaptic depression.

    Directory of Open Access Journals (Sweden)

    Albert Tamburri

    Full Text Available Alzheimer disease is characterized by a gradual decrease of synaptic function and, ultimately, by neuronal loss. There is considerable evidence supporting the involvement of oligomeric amyloid-beta (Aβ in the etiology of Alzheimer's disease. Historically, AD research has mainly focused on the long-term changes caused by Aβ rather than analyzing its immediate effects. Here we show that acute perfusion of hippocampal slice cultures with oligomeric Aβ depresses synaptic transmission within 20 minutes. This depression is dependent on synaptic stimulation and the activation of NMDA-receptors, but not on NMDA-receptor mediated ion flux. It, therefore, appears that Aβ dependent synaptic depression is mediated through a use-dependent metabotropic-like mechanism of the NMDA-receptor, but does not involve NMDA-receptor mediated synaptic transmission, i.e. it is independent of calcium flux through the NMDA-receptor.

  19. Differential interleukin-1 receptor antagonism on pancreatic beta and alpha cells. Studies in rodent and human islets and in normal rats

    DEFF Research Database (Denmark)

    Zumsteg, U; Reimers, J I; Pociot, F;

    1993-01-01

    , mouse and human islets exposed to recombinant human interleukin-1 beta, and on interleukin-1 beta induced changes in blood glucose, serum insulin and serum glucagon levels in Wistar Kyoto rats. The interleukin-1 receptor antagonist reduced the co-mitogenic effect of interleukin-1 beta on mouse and rat......The monokines interleukin-1 alpha and -beta have been implicated as effector molecules in the immune-mediated pancreatic beta-cell destruction leading to insulin-dependent diabetes mellitus. Here we investigated the effects of interleukin-1 receptor antagonism on insulin and glucagon release of rat...... thymocytes with a 50% inhibitory concentration of 10- and 100-fold molar excess, respectively. Complete inhibition was obtained with a 100-1,000-fold molar excess. However, at a 100-fold molar excess the interleukin-1 receptor antagonist did not antagonise the potentiating effect of interleukin-1 beta on rat...

  20. Molecular analysis of T-cell receptor beta genes in cutaneous T-cell lymphoma reveals Jbeta1 bias.

    Science.gov (United States)

    Morgan, Suzanne M; Hodges, Elizabeth; Mitchell, Tracey J; Harris, Susan; Whittaker, Sean J; Smith, John L

    2006-08-01

    Molecular characterization of T-cell receptor junctional region sequences in cutaneous T-cell lymphoma had not been previously reported. We have examined in detail the features of the T-cell receptor beta (TCRB) gene rearrangements in 20 individuals with well-defined stages of cutaneous T-cell lymphoma (CTCL) comprising 10 cases with early-stage mycosis fungoides (MF) and 10 cases with late-stage MF or Sezary syndrome. Using BIOMED-2 PCR primers, we detected a high frequency of clonally rearranged TCR gamma and TCRB genes (17/20 and 15/20 cases, respectively). We carried out sequencing analysis of each complete clonal variable (V)beta-diversity (D)beta-joining(J)beta fingerprint generated by PCR amplification, and determined the primary structure of the Vbeta-Dbeta-Jbeta junctional regions. We observed considerable diversity in the T-cell receptor Vbeta gene usage and complementarity-determining region 3 loops. Although we found that TCRB gene usage in CTCL and normal individuals share common features, our analysis also revealed preferential usage of Jbeta1 genes in all cases with advanced stages of disease.

  1. Live Borrelia burgdorferi preferentially activate interleukin-1 beta gene expression and protein synthesis over the interleukin-1 receptor antagonist.

    Science.gov (United States)

    Miller, L C; Isa, S; Vannier, E; Georgilis, K; Steere, A C; Dinarello, C A

    1992-01-01

    Lyme arthritis is one of the few forms of chronic arthritis in which the cause is known with certainty. Because cytokines are thought to contribute to the pathogenesis of chronic arthritis, we investigated the effect of the Lyme disease spirochete, Borrelia burgdorferi, on the gene expression and synthesis of IL-1 beta and the IL-1 receptor antagonist (IL-1ra) in human peripheral blood mononuclear cells. Live B. burgdorferi induced fivefold more IL-1 beta than IL-1 alpha and sevenfold more IL-1 beta than IL-1ra; LPS or sonicated B. burgdorferi induced similar amounts of all three cytokines. This preferential induction of IL-1 beta was most dramatic in response to a low passage, virulent preparation of B. burgdorferi vs. three high passage avirulent strains. No difference in induction of IL-1ra was seen between these strains. The marked induction of IL-1 beta was partially diminished by heat-treatment and abrogated by sonication; IL-1ra was not affected. This suggested that a membrane component(s) accounted for the preferential induction of IL-1 beta. However, recombinant outer surface protein beta induced little IL-1 beta. By 4 h after stimulation, B. burgdorferi induced sixfold more IL-1 beta protein than LPS. In contrast to LPS-induced IL-1 beta mRNA which reached maximal accumulation after 3 h, B. burgdorferi-induced IL-1 beta mRNA showed biphasic elevations at 3 and 18 h. B. burgdorferi-induced IL-1ra mRNA peaked at 12 h, whereas LPS-induced IL-1ra mRNA peaked at 9 h. IL-1 beta synthesis increased in response to increasing numbers of spirochetes, whereas IL-1ra synthesis did not. The preferential induction by B. burgdorferi of IL-1 beta over IL-1ra is an example of excess agonist over antagonist synthesis induced by a microbial pathogen, and may contribute to the destructive lesion of Lyme arthritis. Images PMID:1387885

  2. Interleukin 2 receptor beta chain expressed in an oligodendroglioma line binds interleukin 2 and delivers growth signal.

    OpenAIRE

    Okamoto, Y; Minamoto, S; Shimizu, K.; Mogami, H; Taniguchi, T.

    1990-01-01

    Interleukin 2 (IL-2) is a potent growth factor for T lymphocytes, playing a crucial role in the immune response. In view of the considerable evidence that the immunoregulatory cytokines (or lymphokines) also play a role in the growth and differentiation of cells in the central nervous system (CNS), we examined the operation of the IL-2 system in a cell line of CNS origin by expressing a cDNA encoding the beta chain of the human IL-2 receptor (IL-2R beta, a 75-kDa protein). When the cDNA was e...

  3. Receptor tyrosine phosphatase beta is expressed in the form of proteoglycan and binds to the extracellular matrix protein tenascin

    DEFF Research Database (Denmark)

    Barnea, G; Grumet, M; Milev, P;

    1994-01-01

    immunohistochemical studies indicated that both RPTP beta and the extracellular matrix protein tenascin are localized in similar regions of the central nervous system. We have performed co-aggregation assays with red and green Co-vaspheres coated with tenascin and 3F8 PG, respectively, showing that the extracellular...... domain of RPTP beta (3F8 PG) binds specifically to tenascin. The interaction between a receptor tyrosine phosphatase and an extracellular matrix protein may have a role in development of the mammalian central nervous system....

  4. Identification of three adjacent amino acids of interleukin-2 receptor beta chain which control the affinity and the specificity of the interaction with interleukin-2.

    OpenAIRE

    Imler, J L; Miyajima, A; Zurawski, G

    1992-01-01

    The beta chain of the interleukin-2 (IL-2) receptor (IL-2R beta) and the interleukin-3 (IL-3) binding protein AIC2A are members of the family of cytokine receptors, which also includes the receptors for growth hormone (GHR) and prolactin. A four amino acid sequence of AIC2A has recently been shown to be critical for IL-3 binding. We analyze here the function of the analogous sequence of human IL-2R beta and identify three amino acids, Ser132, His133 and Tyr134, which play a critical role in I...

  5. Islet-selectivity of G-protein coupled receptor ligands evaluated for PET imaging of pancreatic {beta}-cell mass

    Energy Technology Data Exchange (ETDEWEB)

    Cline, Gary W., E-mail: gary.cline@yale.edu [Yale University School of Medicine (United States); Zhao, Xiaojian [Yale University School of Medicine (United States); Jakowski, Amy B.; Soeller, Walter C.; Treadway, Judith L. [Pfizer Global Research and Development, Pfizer Inc., Groton CT (United States)

    2011-09-02

    Highlights: {yields} We screened G-protein coupled receptors for imaging pancreatic. {yields} Database mining and immunohistochemistry identified GPCRs enriched in {beta}-cells. {yields} In vitro and in vivo assays were used to determine exocrine vs endocrine specificity. {yields} GPCR candidates for imaging of {beta}-cell mass are Prokineticin-1R, mGluR5, and GLP-1R. -- Abstract: A critical unmet need exists for methods to quantitatively measure endogenous pancreatic {beta}-cell mass (BCM) for the clinical evaluation of therapies to prevent or reverse loss of BCM and diabetes progression. Our objective was to identify G-protein coupled receptors (GPCRs) that are expressed with a high degree of specificity to islet {beta}-cells for receptor-targeted imaging of BCM. GPCRs enriched in pancreatic islets relative to pancreas acinar and hepatic tissue were identified using a database screen. Islet-specific expression was confirmed by human pancreas immunohistochemistry (IHC). In vitro selectivity assessment was determined from the binding and uptake of radiolabeled ligands to the rat insulinoma INS-1 832/13 cell line and isolated rat islets relative to the exocrine pancreas cell-type, PANC-1. Tail-vein injections of radioligands into rats were used to determine favorable image criteria of in vivo biodistribution to the pancreas relative to other internal organs (i.e., liver, spleen, stomach, and lungs). Database and IHC screening identified four candidate receptors for further in vitro and in vivo evaluation for PET imaging of BCM: prokineticin-1 receptor (PK-1R), metabotropic glutamate receptor type-5 (mGluR5), neuropeptide Y-2 receptor (NPY-2R), and glucagon-like peptide 1 receptor (GLP-1R). In vitro specificity ratios gave the following receptor rank order: PK-1R > GLP-1R > NPY-2R > mGluR5. The biodistribution rank order of selectivity to the pancreas was found to be PK-1R > VMAT2 {approx} GLP-1R > mGluR5. Favorable islet selectivity and biodistribution

  6. Evaluation of estrogen receptor alpha and beta and progesterone receptor expression and correlation with clinicopathologic factors and proliferative marker Ki-67 in breast cancers

    DEFF Research Database (Denmark)

    Rosa, Fabíola E; Caldeira, José R F; Felipes, Joice;

    2008-01-01

    To elucidate the molecular profile of hormonal steroid receptor status, we analyzed ER-alpha, ER-beta, and PGR mRNA and protein expression in 80 breast carcinomas using reverse transcriptase polymerase chain reaction (RT-PCR), quantitative RT-PCR, and immunohistochemical analysis. Qualitative...... analysis revealed positive expression of ER-alpha, ER-beta, and PGR mRNA in 48%, 59%, and 48% of the breast carcinomas, respectively. ER-alpha, ER-beta, and PGR transcript overexpression was observed in 51%, 0%, and 12% of the cases, respectively, whereas moderate or strong protein expression was detected...... in 68%, 78%, and 49% of the cases, respectively. Tumor grade was negatively correlated with transcript and protein levels of ER-alpha (P = .0169 and P = .0006, respectively) and PGR (P = .0034 and P = .0005, respectively). Similarly, proliferative index Ki-67 was negatively associated with transcript...

  7. Beta-Adrenergic Receptor Population is Up-Regulated in Chicken Skeletal Muscle Cells Treated with Forskolin

    Science.gov (United States)

    Bridge, K. Y.; Young, R. B.; Vaughn, J. R.

    1998-01-01

    Skeletal muscle hypertrophy is promoted by in vivo administration of beta-adrenergic receptor (betaAR) agonists. These compounds presumably exert their physiological action through the betaAR, and alterations in the population of betaAR could potentially change the ability of the cell to respond to the betaAR agonists. Since the intracellular chemical signal generated by the betaAR is cyclic AMP (cAMP), experiments were initiated in primary chicken muscle cell cultures to determine if artificial elevation of intracellular cAMP by treatment with forskolin would alter the population of functional betaAR expressed on the surface of muscle cells. Chicken skeletal muscle cells after 7 days in culture were employed for the experiments because muscle cells have attained a steady state with respect to muscle protein metabolism at this stage. Cells were treated with 0-10 microM forskolin for a total of three days. At the end of the 1, 2, and 3 day treatment intervals, the concentration of cAMP and the betaAR population were measured. Receptor population was measured in intact muscle cell cultures as the difference between total binding of [H-3]CGP-12177 and non-specific binding of [H-3]CGP-12177 in the presence of 1 microM propranolol. Intracellular cAMP concentration was measured by radioimmunoassay. The concentration of cAMP in forskolin-treated cells increased up to 10-fold in a dose dependent manner. Increasing concentrations of forskolin also led to an increase in betaAR population, with a maximum increase of approximately 50% at 10 microM. This increase in PAR population was apparent after only 1 day of treatment, and the pattern of increase was maintained for all 3 days of the treatment period. Thus, increasing the intracellular concentration of cAMP leads to up-regulation of betaAR population. The effect of forskolin on the quantity and apparent synthesis rate of the heavy chain of myosin (mhc) were also investigated. A maximum increase of 50% in the quantity of mhc

  8. Tumour nuclear oestrogen receptor beta 1 correlates inversely with parathyroid tumour weight.

    Science.gov (United States)

    Haglund, Felix; Rosin, Gustaf; Nilsson, Inga-Lena; Juhlin, C Christofer; Pernow, Ylva; Norenstedt, Sophie; Dinets, Andrii; Larsson, Catharina; Hartman, Johan; Höög, Anders

    2015-03-01

    Primary hyperparathyroidism (PHPT) is a common endocrinopathy, frequently caused by a parathyroid adenoma, rarely by a parathyroid carcinoma that lacks effective oncological treatment. As the majority of cases are present in postmenopausal women, oestrogen signalling has been implicated in the tumourigenesis. Oestrogen receptor beta 1 (ERB1) and ERB2 have been recently identified in parathyroid adenomas, the former inducing genes coupled to tumour apoptosis. We applied immunohistochemistry and slide digitalisation to quantify nuclear ERB1 and ERB2 in 172 parathyroid adenomas, atypical adenomas and carcinomas, and ten normal parathyroid glands. All the normal parathyroid glands expressed ERB1 and ERB2. The majority of tumours expressed ERB1 (70.6%) at varying intensities, and ERB2 (96.5%) at strong intensities. Parathyroid carcinomas expressed ERB1 in three out of six cases and ERB2 in five out of six cases. The intensity of tumour nuclear ERB1 staining significantly correlated inversely with tumour weight (P=0.011), and patients whose tumours were classified as ERB1-negative had significantly greater tumour weight as well as higher serum calcium (P=0.002) and parathyroid hormone levels (P=0.003). Additionally, tumour nuclear ERB1 was not expressed differentially with respect to sex or age of the patient. Levels of tumour nuclear ERB2 did not correlate with clinical characteristics. In conclusion, decreased ERB1 immunoreactivity is associated with increased tumour weight in parathyroid adenomas. Given the previously reported correlation with tumour-suppressive signalling, selective oestrogen receptor modulation (SERMs) may play a role in the treatment of parathyroid carcinomas. Future studies of SERMs and oestrogen treatment in PHPT should consider tumour weight as a potential factor in pharmacological responsiveness. PMID:25648860

  9. Tandospirone, a 5-HT1A partial agonist, ameliorates aberrant lactate production in the prefrontal cortex of rats exposed to blockade of N-methy-D-aspartate receptors; Towards the therapeutics of cognitive impairment of schizophrenia

    Directory of Open Access Journals (Sweden)

    Takashi eUehara

    2014-09-01

    Full Text Available Rationale Augmentation therapy with serotonin-1A (5-HT1A receptor partial agonists has been suggested to improve cognitive deficits in patients with schizophrenia. Decreased activity of prefrontal cortex may provide a basis for cognitive deficits of the disease. Lactate plays a significant role in the supply of energy to the brain, and glutamatergic neurotransmission contributes to lactate production.Objectives and methods The purposes of this study were to examine the effect of repeated administration (once a daily for 4 days of tandospirone (0.05 and 5 mg/kg on brain energy metabolism, as represented by extracellular lactate concentration (eLAC in the medial prefrontal cortex (mPFC of young adult rats..Results Four-day treatment with MK-801, an NMDA-R antagonist, prolonged eLAC elevation induced by foot shock stress (FS. Co-administration with the high-dose tandospirone suppressed prolonged FS-induced eLAC elevation in rats receiving MK-801, whereas tandospirone by itself did not affected eLAC increment.Conclusions These results suggest that stimulation of 5-HT1A receptors ameliorates abnormalities of energy metabolism in the mPFC due to blockade of NMDA receptors. These findings provide a possible mechanism based on brain energy metabolism by which 5-HT1A agonism improve cognitive impairment in schizophrenia and related disorders.

  10. Structure and diversity of the T cell antigen receptor beta-chain in a teleost fish.

    Science.gov (United States)

    Partula, S; de Guerra, A; Fellah, J S; Charlemagne, J

    1995-07-15

    Cell-mediated immunity (e.g., allograft rejection) is found in all vertebrates, and these reactions are known to depend on thymus-derived cells in amphibian, avian, and mammalian species. The participation of peripheral T cell-like lymphocytes subpopulations to fish immunity is now well documented, but the developmental origin, migration, and peripheral tissue distribution of these cells remain practically unknown. This is mainly due to the difficulty of efficiently thymectomizing fish at an early stage of development and to the lack of Ab strictly specific for thymocytes and T cell surface Ag. One strategy for analyzing T cell biology in fish would be to characterize the genes encoding polypeptides homologous to the TCR molecules. This report describes cDNA clones from the rainbow trout (Oncorhynchus mykiss) that have sequences very similar to amphibian, avian, and mammalian TCR beta-chains. Three complete trout V beta segments belonging to different families were analyzed; one of them had limited amino acid sequence similarity to the human V beta 20 family. The 10 trout beta-chain-joining segments all retain the invariant mammalian J beta residues, and comparison of 66 V beta-J beta junctions led to the identification of a D beta-like sequence (GGACAGGG) that is shorter than but very similar to the chicken D beta and mammalian D beta 1 sequences. There is considerable diversity at the V beta-D beta and D beta-J beta junctions, suggesting the presence of N-nucleotides. The trout C beta extracellular domain is shorter than mammalian C beta, and the hinge region has no cysteine residue. The transmembrane C beta domain contains a lysine residue that in mammals is thought to be involved in charged interactions with members of the CD3 complex. PMID:7608547

  11. Retinoic acid receptor beta2 and neurite outgrowth in the adult mouse spinal cord in vitro.

    Science.gov (United States)

    Corcoran, Jonathan; So, Po-Lin; Barber, Robert D; Vincent, Karen J; Mazarakis, Nicholas D; Mitrophanous, Kyriacos A; Kingsman, Susan M; Maden, Malcolm

    2002-10-01

    Retinoic acid, acting through the nuclear retinoic acid receptor beta2 (RARbeta2), stimulates neurite outgrowth from peripheral nervous system tissue that has the capacity to regenerate neurites, namely, embryonic and adult dorsal root ganglia. Similarly, in central nervous system tissue that can regenerate, namely, embryonic mouse spinal cord, retinoic acid also stimulates neurite outgrowth and RARbeta2 is upregulated. By contrast, in the adult mouse spinal cord, which cannot regenerate, no such upregulation of RARbeta2 by retinoic acid is observed and no neurites are extended in vitro. To test our hypothesis that the upregulation of RARbeta2 is crucial to neurite regeneration, we have transduced adult mouse or rat spinal cord in vitro with a minimal equine infectious anaemia virus vector expressing RARbeta2. After transduction, prolific neurite outgrowth occurs. Outgrowth does not occur when the cord is transduced with a different isoform of RARbeta nor does it occur following treatment with nerve growth factor. These data demonstrate that RARbeta2 is involved in neurite outgrowth, at least in vitro, and that this gene may in the future be of some therapeutic use. PMID:12235288

  12. Beta-adrenergic receptor sensitivity, autonomic balance and serotonergic activity in practitioners of Transcendental Meditation

    Energy Technology Data Exchange (ETDEWEB)

    Hill, D.A.

    1989-01-01

    The aim of this thesis was to investigate the acute autonomic effects of the Transcendental Meditation Program (TM) and resolve the conflict arising from discrepant neurochemical and psychophysiological data. Three experimental investigations were performed. The first examined beta{sub 2}-adrenergic receptors (AR's) on peripheral blood lymphocytes, via (I{sup 125})iodocyanopindolol binding, in 10 male mediating and 10 age matched non-meditating control subjects, to test the hypothesis that the long-term practice of TM and the TM Sidhi Program (TMSP) reduces end organ sensitivity to adrenergic agonists. The second investigated respiratory sinus arrhythmia (an indirect measure of cardiac Parasympathetic Nervous System tone), and skin resistance (a measure of Sympathetic Nervous System tone) during periods of spontaneous respiratory apneusis, a phenomenon occurring during TM that is known to mark the subjective experience of transcending. The third was within subject investigation of the acute effects of the TMSP on 5-hydroxytryptamine (5-HT) activity. Platelet 5-HT was assayed by high pressure liquid chromatography with electrochemical detection, plasma prolactin (PL) and lutenizing hormone (LH) by radioimmunoassay, tryptophan by spectrofluorimetry, and alpha-1-acid glycoprotein (AGP, a modulator of 5-HT uptake) by radial immunodiffusion assay.

  13. Beta-receptor activation increases sodium current in guinea pig heart

    Institute of Scientific and Technical Information of China (English)

    Hong-wei WANG; Zhi-fang YANG; Yin ZHANG; Jian-min YANG; Yuan-mou LIU; Ci-zhen LI

    2009-01-01

    Aim: To study the influence of β-receptor activation on sodium channel current and the physiological significance of increased sodium current with regard to the increased cardiac output caused by sympathetic excitation.Methods: Multiple experimental approaches, including ECG, action potential recording with conventional microelectrodes, whole-cell current measurements, single-channel recordings, and pumping-force measurements, were applied to guinea pig hearts and isolated ventricular myocytes.Results: Isoprenaline was found to dose-dependently shorten QRS waves, increase the amplitude and the Vmaxof action potentials, aug-ment the fast sodium current, and increase the occurrence frequencies and open time constants of the long-open and burst modes of the sodium channel. Increased levels of membrane-permeable cAMP have similar effects. In the presence of a calcium channel blocker, TTX reversed the increased pumping force produced by isoprenaline.Conclusion: Beta-adrenergic modulation increases the inward sodium current and accelerates the conduction velocity within the ventri-cles by changing the sodium channel modes, which might both be conducive to the synchronous contraction of the heart and enhance its pumping function.

  14. Identification of higenamine in Radix Aconiti Lateralis Preparata as a beta2-adrenergic receptor agonist

    Institute of Scientific and Technical Information of China (English)

    Gang BAI; Yang YANG; Qian SHI; Ze LIU; Qi ZHANG; Yuan-yuan ZHU

    2008-01-01

    Aim:To screen beta2-adrenergic receptor (β+-AR) agonists from Radix Aconiti Lateralis Preparata (RALP) as potential drug leads for asthma using a sensi-tive cell-based agonist assay.Methods:The β+-AR gene was stably expressed by Chinese hamster ovary (CHO) cells also stably expressing a cyclic adenosine monophosphate (AMP) response element-linked enhanced green fluorescent pro-tein reporter gene.The cells were used to screen agonists from high-performance liquid chromatographic fractions of an extract of RALE The fraction with the highest activity was selected for further compound isolation and the study of the structure-activity relationship.Its active compound was further identified by chromatography and mass spectrometry.Results:Bioactivity-directed fraction-ation of the crude extract of RALP led to the isolation and characterization of the effective compound,namely hignamine.It could dose-dependently relax the iso-lated guinea pig trachea strip precontraction with acetylcholine with EC50 value of (2.60±0.36)x 10-5 mol/L.Further in vivo studies also displayed that higuamine could protect experimental asthma model induced by histamine in guinea pigs to prolong the latent periods of asthma.Conclusion:Hignamine,as a β2-AR ago-nist existing in the extract of RALE is the key compound contributing to the suc-cessful relief of the bronchoconstriction.

  15. [Cloning of gene fragment of estrogen receptor-beta and its expression in mouse embryo].

    Science.gov (United States)

    Zhang, Zi-Feng; Fan, Shao-Hua; Lu, Jun; Wu, Dong-Mei; Shan, Qun; Hu, Bin; Li, Fei; Zheng, Yuan-Lin

    2008-03-01

    In order to study the expression and regulation effects of estrogen receptor-beta (ERbeta) in the development of mouse embryo, the primer of ERbeta was designed, the ERbeta fragment was first obtained by RT-PCR and subcloned into plasmids pGEM- 3Z, then the recombinant plasmids were linearized with the restriction enzymes of EcoRand Hind. Using Sp6 and T7 RNA polymerase, the digoxigenin(dig) labeled sense and anti-sense probes were transcriped in vitro, respectively. Then the expression of ERbeta in mouse embryo was examined with the probes by whole-mount in situ hybridization. The results indicated that ERbeta is expressed in the brain, spinal neural tube, genital ridge, pericardium, limb bud and mandibular arch of 10.5 dpc embryo, and is also expressed in the telencephalon, mesencephalon, medulla oblongata, spinal cord and limb bud of 13.5 dpc embryo. These results suggest that ERbeta maybe play a role of regulation in sexual differentiation, primal differentiation of neural tube, further differentiation of three primary cerebral vesicles and spinal cord, generation and differentiation of bone and cartilage of limb bud, development of pericardium and configuration differentiation of mandibular in mouse embryo. PMID:18332005

  16. Structural alterations of transforming growth factor-beta receptor genes in human cervical carcinoma

    NARCIS (Netherlands)

    Chen, TP; De Vries, EGE; Hollema, H; Yegen, HA; Vellucci, VF; Strickler, HD; Hildesheim, A; Reiss, M

    1999-01-01

    The development and progression of invasive uterine cervical carcinomas appear to be associated with the progressive loss of sensitivity to transforming growth factor-beta (TGF beta)-mediated cell cycle arrest. In order to identify possible molecular mechanisms responsible for TGF beta resistance, w

  17. Candidate Gene Study of TRAIL and TRAIL Receptors: Association with Response to Interferon Beta Therapy in Multiple Sclerosis Patients

    Science.gov (United States)

    Órpez-Zafra, Teresa; Pinto-Medel, María Jesús; Oliver-Martos, Begoña; Ortega-Pinazo, Jesús; Arnáiz, Carlos; Guijarro-Castro, Cristina; Varadé, Jezabel; Álvarez-Lafuente, Roberto; Urcelay, Elena; Sánchez-Jiménez, Francisca

    2013-01-01

    TRAIL and TRAIL Receptor genes have been implicated in Multiple Sclerosis pathology as well as in the response to IFN beta therapy. The objective of our study was to evaluate the association of these genes in relation to the age at disease onset (AAO) and to the clinical response upon IFN beta treatment in Spanish MS patients. We carried out a candidate gene study of TRAIL, TRAILR-1, TRAILR-2, TRAILR-3 and TRAILR-4 genes. A total of 54 SNPs were analysed in 509 MS patients under IFN beta treatment, and an additional cohort of 226 MS patients was used to validate the results. Associations of rs1047275 in TRAILR-2 and rs7011559 in TRAILR-4 genes with AAO under an additive model did not withstand Bonferroni correction. In contrast, patients with the TRAILR-1 rs20576-CC genotype showed a better clinical response to IFN beta therapy compared with patients carrying the A-allele (recessive model: p = 8.88×10−4, pc = 0.048, OR = 0.30). This SNP resulted in a non synonymous substitution of Glutamic acid to Alanine in position 228 (E228A), a change previously associated with susceptibility to different cancer types and risk of metastases, suggesting a lack of functionality of TRAILR-1. In order to unravel how this amino acid change in TRAILR-1 would affect to death signal, we performed a molecular modelling with both alleles. Neither TRAIL binding sites in the receptor nor the expression levels of TRAILR-1 in peripheral blood mononuclear cell subsets (monocytes, CD4+ and CD8+ T cells) were modified, suggesting that this SNP may be altering the death signal by some other mechanism. These findings show a role for TRAILR-1 gene variations in the clinical outcome of IFN beta therapy that might have relevance as a biomarker to predict the response to IFN beta in MS. PMID:23658636

  18. Molecular Characterization and Expression Analysis of Adrenergic Receptor Beta 2 (ADRB2) Gene before and after Exercise in the Horse

    OpenAIRE

    Cho, Hyun-Woo; Shin, Sangsu; Song, Ki-Duk; Park, Jeong-woong; Choi, Jae-Young; Lee, Hak-Kyo; Cho, Byung-Wook

    2015-01-01

    The adrenergic receptor beta 2 (ADRB2) plays a role in various physiological responses of the muscle to exercise, such as contraction and relaxation. Given its important role in muscle function, we investigated the structure of the horse ADRB2 gene and its expression pattern after exercise to determine if it can serve as a putative biomarker for recovery. Evolutionary analyses using synonymous and non-synonymous mutation ratios, were compared with other species (human, chimpanzee, mouse, rat,...

  19. Inactivation of the transforming growth factor beta type II receptor in human small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Hougaard, S; Nørgaard, P; Abrahamsen, N;

    1999-01-01

    Transforming growth factor beta (TGF-beta) exerts a growth inhibitory effect on many cell types through binding to two types of receptors, the type I and II receptors. Resistance to TGF-beta due to lack of type II receptor (RII) has been described in some cancer types including small cell lung...... cancer (SCLC). The purpose of this study was to examine the cause of absent RII expression in SCLC cell lines. Northern blot analysis showed that RII RNA expression was very weak in 16 of 21 cell lines. To investigate if the absence of RII transcript was due to mutations, we screened the poly-A tract...... of the mutation, which has not previously been observed in RII, has been linked to exposure to benzo[a]-pyrene, a component of cigarette smoke. Since RII has been mapped to chromosome 3p22 and nearby loci are often hypermethylated in SCLC, it was examined whether the lack of RII expression was due...

  20. Pancreatic beta-cell overexpression of the glucagon receptor gene results in enhanced beta-cell function and mass

    DEFF Research Database (Denmark)

    Gelling, Richard W; Vuguin, Patricia M; Du, Xiu Quan;

    2009-01-01

    In addition to its primary role in regulating glucose production from the liver, glucagon has many other actions, reflected by the wide tissue distribution of the glucagon receptor (Gcgr). To investigate the role of glucagon in the regulation of insulin secretion and whole body glucose homeostasi...

  1. Plasmin-induced migration requires signaling through protease-activated receptor 1 and integrin alpha(9)beta(1).

    Science.gov (United States)

    Majumdar, Mousumi; Tarui, Takehiko; Shi, Biao; Akakura, Nobuaki; Ruf, Wolfram; Takada, Yoshikazu

    2004-09-01

    Plasmin is a major extracellular protease that elicits intracellular signals to mediate platelet aggregation, chemotaxis of peripheral blood monocytes, and release of arachidonate and leukotriene from several cell types in a G protein-dependent manner. Angiostatin, a fragment of plasmin(ogen), is a ligand and an antagonist for integrin alpha(9)beta(1). Here we report that plasmin specifically interacts with alpha(9)beta(1) and that plasmin induces of cells expressing migration recombinant alpha(9)beta(1) (alpha(9)-Chinese hamster ovary (CHO) cells). Migration was dependent on an interaction of the kringle domains of plasmin with alpha(9)beta(1) as well as the catalytic activity of plasmin. Angiostatin, representing the kringle domains of plasmin, alone did not induce the migration of alpha(9)-CHO cells, but simultaneous activation of the G protein-coupled protease-activated receptor (PAR)-1 with an agonist peptide induced the migration on angiostatin, whereas PAR-2 or PAR-4 agonist peptides were without effect. Furthermore, a small chemical inhibitor of PAR-1 (RWJ 58259) and a palmitoylated PAR-1-blocking peptide inhibited plasmin-induced migration of alpha(9)-CHO cells. These results suggest that plasmin induces migration by kringle-mediated binding to alpha(9)beta(1) and simultaneous proteolytic activation of PAR-1. PMID:15247268

  2. Studies of the associations between functional beta2-adrenergic receptor variants and obesity, hypertension and type 2 diabetes in 7,808 white subjects

    DEFF Research Database (Denmark)

    Gjesing, A P; Andersen, G; Burgdorf, K S;

    2007-01-01

    Functional and common Arg16Gly and Gln27Glu polymorphisms have been identified in ADRB2, the gene encoding the beta2-adrenergic receptor. These variants have previously been examined for association with obesity, hypertension and diabetes with inconclusive results.......Functional and common Arg16Gly and Gln27Glu polymorphisms have been identified in ADRB2, the gene encoding the beta2-adrenergic receptor. These variants have previously been examined for association with obesity, hypertension and diabetes with inconclusive results....

  3. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (beta2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agen

  4. Blockade of Cannabinoid CB1 receptor attenuates the acquisition of morphine-induced conditioned place preference along with a downregulation of ERK, CREB phosphorylation, and BDNF expression in the nucleus accumbens and hippocampus.

    Science.gov (United States)

    Zhang, Jianbo; Wang, Na; Chen, Bo; Wang, Yi'nan; He, Jing; Cai, Xintong; Zhang, Hongbo; Wei, Shuguang; Li, Shengbin

    2016-09-01

    Cannabinoid CB1 receptor (CB1R) is highly expressed in the mesocorticolimbic system and associated with drug craving and relapse. Clinical trials suggest that CB1R antagonists may represent new therapies for drug addiction. However, the downstream signaling of CB1R is not fully elucidated. In the present study, we investigated the relationship between CB1R and the extracellular signal-regulated kinase (ERK), cAMP response element-binding protein (CREB), brain-derived neurotrophic factor (BDNF) signaling in the nucleus accumbens (NAc) and hippocampus in morphine-induced conditioned place preference (CPP), which is used to assess the morphine-induced reward memory. The protein level of CB1R, ERK, CREB, and BDNF were detected by western blotting. Additionally, a CB1R antagonist, AM251, was used to study whether blockade of CB1R altered the CPP and above-mentioned molecules. We found an increase of CB1R expression in the NAc and hippocampus of the mice following morphine CPP, but not those after repeated morphine in home cage without context exposure (NO-CPP). Both morphine CPP and NO-CPP induced an upregulation of ERK, CREB phosphorylation and BDNF expression. Furthermore, pretreatment with AM251 before morphine attenuated the CPP acquisition and CB1R expression as well as the activation of ERK-CREB-BDNF cascade. Collectively, these findings demonstrate that (1) Repeated morphine with context exposures but not merely the pharmacological effects of morphine increased CB1R expression both in the NAc and hippocampus. (2) CB1R antagonist mediated blockade of ERK-CREB-BDNF signaling activation in the NAc and hippocampus may be an important mechanism underlying the attenuation of morphine CPP. PMID:27461790

  5. Triiodothyronine receptor beta-2 messenger ribonucleic acid expression by somatotropes and thyrotropes: effect of propylthiouracil-induced hypothyroidism in rats.

    Science.gov (United States)

    Childs, G V; Taub, K; Jones, K E; Chin, W W

    1991-11-01

    mRNA for a thyroid hormone receptor isoform that is unique to the pituitary gland (TR beta-2) is down-regulated by T3. Increases in the expression of this mRNA are seen in rats rendered hypothyroid by treatment with propylthiouracil (PTU). This study used dual labeling to determine which pituitary cells expressed TR beta-2 mRNA in normal and PTU-treated rats. In situ hybridization protocols localized the mRNA (with biotinylated complementary oligonucleotide probes detected by avidin-biotin-peroxidase), and immunoperoxidase protocols identified the pituitary hormone proteins. In dispersed pituitary cells, 20 +/- 2% (average +/- SD) of cells from normal rats and 30 +/- 3% of cells from PTU-treated rats were labeled for TR beta-2 mRNA. PTU caused increases in the area of the labeled cells (from 114 +/- 11 to 225 +/- 7 microns 2), the area of the label per cell (from 27 +/- 3 to 71 +/- 11 microns 2), and label density. PTU produced increases in the percentage of TSH cells from 8 +/- 1% to 19 +/- 2%, decreases in the percentage of GH cells from 27 +/- 3% to 11 +/- 2%, and no change in other cell types. After dual labeling, 73% of cells that expressed TR beta-2 mRNA stored either TSH (35 +/- 8) or GH (38 +/- 6). Less than 10% stored other hormones. When each cell type was analyzed, 56 +/- 3% of TSH cells and 43 +/- 4% of GH cells expressed TR beta-2 mRNA. When these percentages were multiplied by the percentages of each cell type in the overall population, TSH and GH cells with TR beta-2 mRNA represented 6.8 +/- 1% and 11.6 +/- 1% of the pituitary cells, respectively. Less than 1% of all pituitary cells expressed TR beta-2 and ACTH (0.9 +/- 0.06), LH (0.8 +/- 0.1), FSH (0.8 +/- 0.1), and PRL (0.9 +/- 0.04). PTU treatment increased the percentage of TSH cells with TR beta-2 mRNA to 72 +/- 4% and decreased the percentage of GH cells with TR beta-2 mRNA to 30 +/- 3%. However, some enlarged putative TSH cells could not be identified by immunolabel because the storage levels

  6. Systemic blockade of dopamine D2-like receptors increases high-voltage spindles in the globus pallidus and motor cortex of freely moving rats.

    Directory of Open Access Journals (Sweden)

    Chen Yang

    Full Text Available High-voltage spindles (HVSs have been reported to appear spontaneously and widely in the cortical-basal ganglia networks of rats. Our previous study showed that dopamine depletion can significantly increase the power and coherence of HVSs in the globus pallidus (GP and motor cortex of freely moving rats. However, it is unclear whether dopamine regulates HVS activity by acting on dopamine D₁-like receptors or D₂-like receptors. We employed local-field potential and electrocorticogram methods to simultaneously record the oscillatory activities in the GP and primary motor cortex (M1 in freely moving rats following systemic administration of dopamine receptor antagonists or saline. The results showed that the dopamine D₂-like receptor antagonists, raclopride and haloperidol, significantly increased the number and duration of HVSs, and the relative power associated with HVS activity in the GP and M1 cortex. Coherence values for HVS activity between the GP and M1 cortex area were also significantly increased by dopamine D₂-like receptor antagonists. On the contrary, the selective dopamine D₁-like receptor antagonist, SCH23390, had no significant effect on the number, duration, or relative power of HVSs, or HVS-related coherence between M1 and GP. In conclusion, dopamine D₂-like receptors, but not D₁-like receptors, were involved in HVS regulation. This supports the important role of dopamine D₂-like receptors in the regulation of HVSs. An siRNA knock-down experiment on the striatum confirmed our conclusion.

  7. beta-TrCP inhibition reduces prostate cancer cell growth via upregulation of the aryl hydrocarbon receptor.

    Directory of Open Access Journals (Sweden)

    Udi Gluschnaider

    Full Text Available BACKGROUND: Prostate cancer is a common and heterogeneous disease, where androgen receptor (AR signaling plays a pivotal role in development and progression. The initial treatment for advanced prostate cancer is suppression of androgen signaling. Later on, essentially all patients develop an androgen independent stage which does not respond to anti hormonal treatment. Thus, alternative strategies targeting novel molecular mechanisms are required. beta-TrCP is an E3 ligase that targets various substrates essential for many aspects of tumorigenesis. METHODOLOGY/PRINCIPAL FINDINGS: Here we show that beta-TrCP depletion suppresses prostate cancer and identify a relevant growth control mechanism. shRNA targeted against beta-TrCP reduced prostate cancer cell growth and cooperated with androgen ablation in vitro and in vivo. We found that beta-TrCP inhibition leads to upregulation of the aryl hydrocarbon receptor (AhR mediating the therapeutic effect. This phenomenon could be ligand independent, as the AhR ligand 2,3,7,8-Tetrachlorodibenzo-p-Dioxin (TCDD did not alter prostate cancer cell growth. We detected high AhR expression and activation in basal cells and atrophic epithelial cells of human cancer bearing prostates. AhR expression and activation is also significantly higher in tumor cells compared to benign glandular epithelium. CONCLUSIONS/SIGNIFICANCE: Together these observations suggest that AhR activation may be a cancer counteracting mechanism in the prostate. We maintain that combining beta-TrCP inhibition with androgen ablation could benefit advanced prostate cancer patients.

  8. Transforming growth factor beta receptor II polymorphisms are associated with Kawasaki disease

    Directory of Open Access Journals (Sweden)

    Yu Mi Choi

    2012-01-01

    Full Text Available Purpose : Transforming growth factor beta receptor 2 (TGFBR2 is a tumor suppressor gene that plays a role in the differentiation of striated cells and remodeling of coronary arteries. Single nucleotide polymorphisms (SNPs of this gene are associated with Marfan syndrome and sudden death in patients with coronary artery disease. Cardiovascular remodeling and T cell activation of TGFBR2 gene suggest that the TGFBR2 gene SNPs are related to the pathogenesis of Kawasaki disease (KD and coronary artery lesion (CAL. Methods : The subjects were 105 patients with KD and 500 healthy adults as controls. Mean age of KD group was 32 months age and 26.6% of those had CAL. We selected TGFBR2 gene SNPs from serum and performed direct sequencing. Results : The sequences of the eleven SNPs in the TGFBR2 gene were compared between the KD group and controls. Three SNPs (rs1495592, rs6550004, rs795430 were associated with development of KD (P=0.019, P=0.026, P=0.016, respectively. One SNP (rs1495592 was associated with CAL in KD group (P=0.022. Conclusion : Eleven SNPs in TGFBR2 gene were identified at that time the genome wide association. But, with the change of the data base, only six SNPs remained associated with the TGFBR2 gene. One of the six SNPs (rs6550004 was associated with development of KD. One SNP associated with CAL (rs1495592 was disassociated from the TGFBR2 gene. The other five SNPs were not functionally identified, but these SNPs are notable because the data base is changing. Further studies involving larger group of patients with KD are needed.

  9. Effect of blockade of neuropeptide Y receptor on aortic intima-media thickness and adipose tissue characteristics in normal and obese mice

    OpenAIRE

    Masoud Alasvand; Bahman Rashidi; Shaghayegh Haghjooy Javanmard; Majid Khazaei

    2015-01-01

    Objective(s): Atherosclerosis is an important risk factor for coronary heart disease. Neuropeptide Y (NPY) and its receptors, located in peripheral tissue such as white adipose tissue, have been linked to obesity and fat storage. The role of NPY in atherosclerosis has not yet been fully studied, so this study was conducted to further investigate the effect of BIIE 0246, an NPY receptor antagonist, on aortic intima-media thickness and size and number of adipocyte cells in normal and obese mice...

  10. Growth suppression by transforming growth factor beta 1 of human small-cell lung cancer cell lines is associated with expression of the type II receptor

    DEFF Research Database (Denmark)

    Nørgaard, P; Damstrup, L; Rygaard, K;

    1994-01-01

    was observed in two cell lines expressing only type III receptor and in TGF-beta-r negative cell lines. In two cell lines expressing all three receptor types, growth suppression was accompanied by morphological changes. To evaluate the possible involvement of the retinoblastoma protein (pRb) in mediating...... the growth-suppressive effect of TGF-beta 1, the expression of functional pRb, as characterised by nuclear localisation, was examined by immunocytochemistry. Nuclear association of pRb was only seen in two of the five TGF-beta 1-responsive cell lines. These results indicate that in SCLC pRb is not required...

  11. Why not treat human cancer with interleukin-1 blockade?

    NARCIS (Netherlands)

    Dinarello, C.A.

    2010-01-01

    The clinical successes of targeting angiogenesis provide a basis for trials of interleukin-1 (IL-1) blockade and particularly anti-IL-1beta as an add-on therapy in human metastatic disease. In animal studies for over 20 years, IL-1 has been demonstrated to increase adherence of tumor cells to the en

  12. Pathologically activated neuroprotection via uncompetitive blockade of N-methyl-D-aspartate receptors with fast off-rate by novel multifunctional dimer bis(propyl)-cognitin.

    Science.gov (United States)

    Luo, Jialie; Li, Wenming; Zhao, Yuming; Fu, Hongjun; Ma, Dik-Lung; Tang, Jing; Li, Chaoying; Peoples, Robert W; Li, Fushun; Wang, Qinwen; Huang, Pingbo; Xia, Jun; Pang, Yuanping; Han, Yifan

    2010-06-25

    Uncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists with fast off-rate (UFO) may represent promising drug candidates for various neurodegenerative disorders. In this study, we report that bis(propyl)-cognitin, a novel dimeric acetylcholinesterase inhibitor and gamma-aminobutyric acid subtype A receptor antagonist, is such an antagonist of NMDA receptors. In cultured rat hippocampal neurons, we demonstrated that bis(propyl)-cognitin voltage-dependently, selectively, and moderately inhibited NMDA-activated currents. The inhibitory effects of bis(propyl)-cognitin increased with the rise in NMDA and glycine concentrations. Kinetics analysis showed that the inhibition was of fast onset and offset with an off-rate time constant of 1.9 s. Molecular docking simulations showed moderate hydrophobic interaction between bis(propyl)-cognitin and the MK-801 binding region in the ion channel pore of the NMDA receptor. Bis(propyl)-cognitin was further found to compete with [(3)H]MK-801 with a K(i) value of 0.27 mum, and the mutation of NR1(N616R) significantly reduced its inhibitory potency. Under glutamate-mediated pathological conditions, bis(propyl)-cognitin, in contrast to bis(heptyl)-cognitin, prevented excitotoxicity with increasing effectiveness against escalating levels of glutamate and much more effectively protected against middle cerebral artery occlusion-induced brain damage than did memantine. More interestingly, under NMDA receptor-mediated physiological conditions, bis(propyl)-cognitin enhanced long-term potentiation in hippocampal slices, whereas MK-801 reduced and memantine did not alter this process. These results suggest that bis(propyl)-cognitin is a UFO antagonist of NMDA receptors with moderate affinity, which may provide a pathologically activated therapy for various neurodegenerative disorders associated with NMDA receptor dysregulation. PMID:20404346

  13. Pathologically activated neuroprotection via uncompetitive blockade of N-methyl-D-aspartate receptors with fast off-rate by novel multifunctional dimer bis(propyl)-cognitin.

    Science.gov (United States)

    Luo, Jialie; Li, Wenming; Zhao, Yuming; Fu, Hongjun; Ma, Dik-Lung; Tang, Jing; Li, Chaoying; Peoples, Robert W; Li, Fushun; Wang, Qinwen; Huang, Pingbo; Xia, Jun; Pang, Yuanping; Han, Yifan

    2010-06-25

    Uncompetitive N-methyl-d-aspartate (NMDA) receptor antagonists with fast off-rate (UFO) may represent promising drug candidates for various neurodegenerative disorders. In this study, we report that bis(propyl)-cognitin, a novel dimeric acetylcholinesterase inhibitor and gamma-aminobutyric acid subtype A receptor antagonist, is such an antagonist of NMDA receptors. In cultured rat hippocampal neurons, we demonstrated that bis(propyl)-cognitin voltage-dependently, selectively, and moderately inhibited NMDA-activated currents. The inhibitory effects of bis(propyl)-cognitin increased with the rise in NMDA and glycine concentrations. Kinetics analysis showed that the inhibition was of fast onset and offset with an off-rate time constant of 1.9 s. Molecular docking simulations showed moderate hydrophobic interaction between bis(propyl)-cognitin and the MK-801 binding region in the ion channel pore of the NMDA receptor. Bis(propyl)-cognitin was further found to compete with [(3)H]MK-801 with a K(i) value of 0.27 mum, and the mutation of NR1(N616R) significantly reduced its inhibitory potency. Under glutamate-mediated pathological conditions, bis(propyl)-cognitin, in contrast to bis(heptyl)-cognitin, prevented excitotoxicity with increasing effectiveness against escalating levels of glutamate and much more effectively protected against middle cerebral artery occlusion-induced brain damage than did memantine. More interestingly, under NMDA receptor-mediated physiological conditions, bis(propyl)-cognitin enhanced long-term potentiation in hippocampal slices, whereas MK-801 reduced and memantine did not alter this process. These results suggest that bis(propyl)-cognitin is a UFO antagonist of NMDA receptors with moderate affinity, which may provide a pathologically activated therapy for various neurodegenerative disorders associated with NMDA receptor dysregulation.

  14. Specific in vitro toxicity of crude and refined petroleum products: II. Estrogen (alpha and beta) and androgen receptor-mediated responses in yeast assays.

    NARCIS (Netherlands)

    Vrabie, C.M.; Candido, A.; van Duursen, M.B.M.; Jonker, M.T.O.

    2010-01-01

    The present study is the second in a series aiming at a systematic inventory of specific toxic effects of oils. By employing a recombinant yeast stably transfected with human estrogen receptor-alpha (ERalpha) or -beta (ERbeta) or androgen receptor (AR) and expressing yeast enhanced green fluorescent

  15. Effect of blockade of neuropeptide Y receptor on aortic intima-media thickness and adipose tissue characteristics in normal and obese mice

    Directory of Open Access Journals (Sweden)

    Masoud Alasvand

    2015-05-01

    Full Text Available Objective(s: Atherosclerosis is an important risk factor for coronary heart disease. Neuropeptide Y (NPY and its receptors, located in peripheral tissue such as white adipose tissue, have been linked to obesity and fat storage. The role of NPY in atherosclerosis has not yet been fully studied, so this study was conducted to further investigate the effect of BIIE 0246, an NPY receptor antagonist, on aortic intima-media thickness and size and number of adipocyte cells in normal and obese mice. Materials and Methods: Tests were performed on 24 male C57BL/6 mice. The animals were divided into four groups as follows: control (normal, obese (high-fat diet, normal+NPY receptor antagonist (1 μM, 100 µl/Kg BIIE0246 intraperitoneally and obese+NPY receptor antagonist (n=6 each. After 14 days, the animals were sacrificed and epididymal adipose tissue and thoracic aorta were removed. Evaluations were made for adipocyte cell number and size and for aortic intima-media thickness. Results: The group on a high-fat diet showed a significantly decreased number of adipocyte cells and increased cell size (P0.05. Conclusion: NPY receptor antagonist had no effect on adipocyte cell size and aortic intima-media thickness; however, it decreased cell number in the normal group indicating likely involvement in the progression of obesity

  16. Human-Specific SNP in Obesity Genes, Adrenergic Receptor Beta2 (ADRB2), Beta3 (ADRB3), and PPAR γ2 (PPARG), during Primate Evolution

    Science.gov (United States)

    Takenaka, Akiko; Nakamura, Shin; Mitsunaga, Fusako; Inoue-Murayama, Miho; Udono, Toshifumi; Suryobroto, Bambang

    2012-01-01

    Adrenergic-receptor beta2 (ADRB2) and beta3 (ADRB3) are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM) in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG) is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and resistance to NIDDM. In humans, energy-expense alleles, Gln27 in ADRB2 and Trp64 in ADRB3, are at higher frequencies than Glu27 and Arg64, respectively, but Ala12 in PPARG is at lower frequency than Pro12. Adaptation of humans for lipolysis, thermogenesis, and reduction of fat accumulation could be considered by examining which alleles in these genes are dominant in non-human primates (NHP). All NHP (P. troglodytes, G. gorilla, P. pygmaeus, H. agilis and macaques) had energy-thrifty alleles, Gly16 and Glu27 in ADRB2, and Arg64 in ADRB3, but did not have energy-expense alleles, Arg16, Gln27 and Trp64 alleles. In PPARG gene, all NHP had large adipocyte accumulating type, the Pro12 allele. Conclusions These results indicate that a tendency to produce much more heat through the energy-expense alleles developed only in humans, who left tropical rainforests for savanna and developed new features in their heat-regulation systems, such as reduction of body hair and increased evaporation of water, and might have helped the protection of entrails from cold at night, especially in glacial periods. PMID:22937051

  17. Human-specific SNP in obesity genes, adrenergic receptor beta2 (ADRB2, Beta3 (ADRB3, and PPAR γ2 (PPARG, during primate evolution.

    Directory of Open Access Journals (Sweden)

    Akiko Takenaka

    Full Text Available UNLABELLED: Adrenergic-receptor beta2 (ADRB2 and beta3 (ADRB3 are obesity genes that play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. The Glu27 allele in ADRB2 and the Arg64 allele in ADRB3 are associated with abdominal obesity and early onset of non-insulin-dependent diabetes mellitus (NIDDM in many ethnic groups. Peroxisome proliferator-activated receptor γ (PPARG is required for adipocyte differentiation. Pro12Ala mutation decreases PPARG activity and resistance to NIDDM. In humans, energy-expense alleles, Gln27 in ADRB2 and Trp64 in ADRB3, are at higher frequencies than Glu27 and Arg64, respectively, but Ala12 in PPARG is at lower frequency than Pro12. Adaptation of humans for lipolysis, thermogenesis, and reduction of fat accumulation could be considered by examining which alleles in these genes are dominant in non-human primates (NHP. All NHP (P. troglodytes, G. gorilla, P. pygmaeus, H. agilis and macaques had energy-thrifty alleles, Gly16 and Glu27 in ADRB2, and Arg64 in ADRB3, but did not have energy-expense alleles, Arg16, Gln27 and Trp64 alleles. In PPARG gene, all NHP had large adipocyte accumulating type, the Pro12 allele. CONCLUSIONS: These results indicate that a tendency to produce much more heat through the energy-expense alleles developed only in humans, who left tropical rainforests for savanna and developed new features in their heat-regulation systems, such as reduction of body hair and increased evaporation of water, and might have helped the protection of entrails from cold at night, especially in glacial periods.

  18. Traceable Coulomb Blockade Thermometry

    CERN Document Server

    Hahtela, Ossi; Kemppinen, Antti; Meschke, Matthias; Prunnila, Mika; Gunnarsson, David; Roschier, Leif; Penttila, Jari; Pekola, Jukka

    2016-01-01

    We present a measurement and analysis scheme for determining traceable thermodynamic temperature at cryogenic temperatures using Coulomb blockade thermometry. The uncertainty of the electrical measurement is improved by utilizing two sampling digital voltmeters instead of the traditional lock-in technique. The remaining uncertainty is dominated by that of the numerical analysis of the measurement data. Two analysis methods, the numerical fitting of the full conductance curve and measuring the height of the conductance dip yield almost identical results. The complete uncertainty analysis shows that the relative expanded uncertainty (k = 2) in determining the thermodynamic temperature in the temperature range from 20 mK to 200 mK is below 1 %. A good agreement within the measurement uncertainty is experimentally demonstrated between the Coulomb blockade thermometer and a superconducting reference point device that has been directly calibrated against the Provisional Low Temperature Scale of 2000.

  19. Bradykinin antagonist counteracts the acute effect of both angiotensin-converting enzyme inhibition and of angiotensin receptor blockade on the lower limit of autoregulation of cerebral blood flow

    DEFF Research Database (Denmark)

    Sigurdsson, Sigurdur T; Paulson, Olaf B; Høj Nielsen, Arne;

    2014-01-01

    The lower limit of autoregulation of cerebral blood flow (CBF) can be modulated with both angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARB). The influence of bradykinin antagonism on ARB-induced changes was the subject of this study. CBF was measured in Sprague......-Dawley rats with laser Doppler technique. The blood pressure was lowered by controlled bleeding. Six groups of rats were studied: a control group and five groups given drugs intravenously: an ACE inhibitor (enalaprilat), an ARB (candesartan), a bradykinin-2 receptor antagonist (Hoe 140), a combination...

  20. Structural Characterization of the Boca/Mesd Maturation Factors for LDL-Receptor-Type beta Propeller Domains

    Energy Technology Data Exchange (ETDEWEB)

    M Collins; W Hendrickson

    2011-12-31

    Folding and trafficking of low-density lipoprotein receptor (LDLR) family members, which play essential roles in development and homeostasis, are mediated by specific chaperones. The Boca/Mesd chaperone family specifically promotes folding and trafficking of the YWTD {beta} propeller-EGF domain pair found in the ectodomain of all LDLR members. Limited proteolysis, NMR spectroscopy, analytical ultracentrifugation, and X-ray crystallography were used to define a conserved core composed of a structured domain that is preceded by a disordered N-terminal region. High-resolution structures of the ordered domain were determined for homologous proteins from three metazoans. Seven independent protomers reveal a novel ferrodoxin-like superfamily fold with two distinct {beta} sheet topologies. A conserved hydrophobic surface forms a dimer interface in each crystal, but these differ substantially at the atomic level, indicative of nonspecific hydrophobic interactions that may play a role in the chaperone activity of the Boca/Mesd family.

  1. Interleukin 1 (IL-1) type I receptors mediate activation of rat hypothalamus-pituitary-adrenal axis and interleukin 6 production as shown by receptor type selective deletion mutants of IL-1beta.

    Science.gov (United States)

    Van Dam, A M; Malinowsky, D; Lenczowski, M J; Bartfai, T; Tilders, F J

    1998-06-01

    The cytokine interleukin 1 (IL-1) plays an important role in the activation of the hypothalamus-pituary-adrenal (HPA)-axis and interleukin 6 (IL-6) production during infection or inflammation. Which of the interleukin-1 receptor types mediates these effects is not known. To investigate this issue a pharmacological approach was chosen by using recently developed IL-1 receptor type selective ligands. Rats were given one of various doses of recombinant human IL-1beta (rhIL-1beta; 1 and 10 microg/kg) and of several IL-1beta mutants (DeltaSND, DeltaQGE and DeltaI; 1, 10 and 100 microg/kg), that differ in their affinities for the IL-1 type I receptor but have similar affinities for the IL-1 type II receptor. One hour after intravenous administration of rhIL-1beta or IL-1beta mutants, plasma levels of ACTH, corticosterone (cort) and IL-6 were measured. Doses of 1 and 10 microg/kg rhIL-1beta markedly elevated plasma levels of ACTH, cort and IL-6. However, 10-100-fold higher doses of IL-1beta mutants DeltaSND and DeltaQGE and at least 100-fold higher doses of DeltaI have to be administered to increase plasma levels of ACTH, cort and IL-6. The potency differences correlate with their respective affinity for the type I receptor but not with that of the IL-1 type II receptor. It is concluded that IL-1beta induced ACTH, cort and IL-6 production is mediated by interleukin 1 type I receptors.

  2. Beta-adrenergic receptors support attention to extinction learning that occurs in the absence, but not the presence, of a context change

    Directory of Open Access Journals (Sweden)

    Marion Emma André

    2015-05-01

    Full Text Available The noradrenergic (NA-system is an important regulator of cognitive function. It contributes to extinction learning(EL, and in disorders where EL is impaired NA-dysfunction has been postulated. We explored whether NA acting on beta-adrenergic-receptors (β-AR, regulates EL that depends on context, but is not fear-associated. We assessed behaviour in an ‘AAA’ or ‘ABA’ paradigm: rats were trained for 3 days in a T-maze(context-A to learn that a reward is consistently found in the goal arm, despite low reward probability. This was followed on day 4 by EL(unrewarded, whereby in the ABA-paradigm, EL was reinforced by a context change (B, and in the AAA-paradigm, no context change occurred. On day 5, re-exposure to the A-context (unrewarded occurred. Typically, in control ‘AAA’ animals EL occurred on day 4 that progressed further on day 5. In control ‘ABA’ animals, EL also occurred on day 4, followed by renewal of the previously learned (A behavior on day 5, that was followed (in day 5 by extinction of this behavior, as the animals realised that no food reward would be given.Treatment with the β-AR-antagonist, propranolol, prior to EL on day 4, impaired EL in the AAA-paradigm. In the ‘ABA’ paradigm, antagonist treatment on day 4, had no effect on extinction that was reinforced by a context change (B. Furthermore, β-AR-antagonism prior to renewal testing (on day 5 in the ABA-paradigm, resulted in normal renewal behavior, although subsequent extinction of responses during day 5 was prevented by the antagonist. Thus, under both treatment conditions, β-AR-antagonism prevented extinction of the behavior learned in the ‘A’ context.β-AR-blockade during an overt context change did not prevent EL, whereas β-AR were required for EL in an unchanging context. These data suggest that β-AR may support EL by reinforcing attention towards relevant changes in the previously learned experience, and that this process supports extinction

  3. Association of beta 2 -adrenergic receptor gene polymorphisms and nocturnal asthma in Saudi patients

    Directory of Open Access Journals (Sweden)

    Al-Rubaish Abdullah

    2011-01-01

    Full Text Available Background and Objectives : Two polymorphisms of beta 2 -adrenergic receptor (β2 -AR gene, namely the substitution from arginine (Arg to glycine (Gly at codon 16 and from glutamine (Gln to glutamic (Glu at codon 27, are linked with functional changes in the β2 -AR in the respiratory system even though they are not deemed to be susceptibility genes for asthma per se. The objective of this study was to investigate this association in a subset of asthmatic patients, namely those with nocturnal asthma. Methods : The β2 -AR gene polymorphisms at codon 16 and 27 were assessed in 40 patients clinically diagnosed with nocturnal asthma and 96 normal controls. Genomic DNA was obtained from whole blood and genotyping was carried out by a PCR based restriction fragment length polymorphism technique. Results : There was a statistically significant difference in genotype frequencies at codon 16 (Arg/Gly between nocturnal asthmatic patients and normal control subjects (P < 0.05. However, there was no statistically significant difference in allele frequencies between the two groups. In addition, there was a significant association between Arg16-Gly genotype with nocturnal asthma compared to homozygous Gly16 (codominant model P = 0.0033, OR = 3.69: 95% CI: 1.49-9.12. However, there were no statistically significant differences in genotype and allele frequencies at codon 27 (Gln/Glu between the normal control and nocturnal asthmatic groups (χ2 = 1.81, P = 0.41. The results also indicate that linkage disequilibrium existed between the β2 -AR codon 16 and β2 -AR codon 27 polymorphism (/ D΄/ = 0.577. The data for all haplotypes did not show a statistically significant association. Conclusion : We present the genotype and allele frequencies of β2 -AR gene polymorphisms in normal Saudi subjects and nocturnal asthmatic patients. There was a significant difference in genotype frequencies at codon 16 (Arg/Gly. However, our study indicates a poor association of

  4. Selective estrogen receptor-beta (SERM-beta) compounds modulate raphe nuclei tryptophan hydroxylase-1 (TPH-1) mRNA expression and cause antidepressant-like effects in the forced swim test.

    Science.gov (United States)

    Clark, J A; Alves, S; Gundlah, C; Rocha, B; Birzin, E T; Cai, S-J; Flick, R; Hayes, E; Ho, K; Warrier, S; Pai, L; Yudkovitz, J; Fleischer, R; Colwell, L; Li, S; Wilkinson, H; Schaeffer, J; Wilkening, R; Mattingly, E; Hammond, M; Rohrer, S P

    2012-11-01

    Estrogen acts through two molecularly distinct receptors termed estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) which bind estradiol with similar affinities and mediate the effects of estrogen throughout the body. ERα plays a major role in reproductive physiology and behavior, and mediates classic estrogen signaling in such tissues as the uterus, mammary gland, and skeleton. ERβ, however, modulates estrogen signaling in the ovary, the immune system, prostate, gastrointestinal tract, and hypothalamus, and there is some evidence that ERβ can regulate ERα activity. Moreover, ERβ knockout studies and receptor distribution analyses in the CNS suggest that this receptor may play a role in the modulation of mood and cognition. In recent years several ERβ-specific compounds (selective estrogen receptor beta modulators; SERM-beta) have become available, and research suggests potential utility of these compounds in menopausal symptom relief, breast cancer prevention, diseases that have an inflammatory component, osteoporosis, cardiovascular disease, and inflammatory bowel disease, as well as modulation of mood, and anxiety. Here we demonstrate an antidepressant-like effect obtained using two SERM-beta compounds, SERM-beta1 and SERM-beta2. These compounds exhibit full agonist activity at ERβ in a cell based estrogen response element (ERE) transactivation assay. SERM-beta1 and 2 are non-proliferative with respect to breast as determined using the MCF-7 breast cancer cell-based assay and non-proliferative in the uterus as determined by assessing the effects of SERM-beta compounds on immature rat uterine weight and murine uterine weight. In vivo SERM-beta1 and 2 are brain penetrant and display dose dependent efficacy in the murine dorsal raphe assays for induction of tryptophan hydroxylase mRNA and progesterone receptor protein. These compounds show activity in the murine forced swim test and promote hippocampal neurogenesis acutely in rats. Taken

  5. Placental expression of estrogen receptor beta and its hormone binding variant – comparison with estrogen receptor alpha and a role for estrogen receptors in asymmetric division and differentiation of estrogen-dependent cells

    Directory of Open Access Journals (Sweden)

    Henley Donald C

    2003-04-01

    Full Text Available Abstract During human pregnancy, the production of 17-beta-estradiol (E2 rises steadily to eighty fold at term, and placenta has been found to specifically bind estrogens. We have recently demonstrated the expression of estrogen receptor alpha (ER-alpha protein in human placenta and its localization in villous cytotrophoblast (CT, vascular pericytes, and amniotic fibroblasts. In vitro, E2 stimulated development of large syncytiotrophoblast (ST aggregates. In the present study we utilized ER-beta affinity purified polyclonal (N19:sc6820 and ER-alpha monoclonal (clone h-151 antibodies. Western blot analysis revealed a single ~52 kDa ER-beta band in chorionic villi (CV protein extracts. In CV, strong cytoplasmic ER-beta immunoreactivity was confined to ST. Dual color immunohistochemistry revealed asymmetric segregation of ER-alpha in dividing villous CT cells. Prior to separation, the cell nuclei more distant from ST exhibited high ER-alpha, while cell nuclei associated with ST showed diminution of ER-alpha and appearance of ER-beta. In trophoblast cultures, development of ST aggregates was associated with diminution of ER-alpha and appearance of ER-beta immunoreactivity. ER-beta was also detected in endothelial cells, amniotic epithelial cells and fibroblasts, extravillous trophoblast (nuclear and cytoplasmic and decidual cells (cytoplasmic only. In addition, CFK-E12 (E12 and CWK-F12 (F12 monoclonal antibodies, which recognize ~64 kDa ER-beta with hormone binding domain, showed nuclear-specific reactivity with villous ST, extravillous trophoblast, and amniotic epithelium and fibroblasts. Western blot analysis indicated abundant expression of a ~64 kDa ER-beta variant in trophoblast cultures, significantly higher when compared to the chorionic villi and freshly isolated trophoblast cell protein extracts. This is the first report on ER-beta expression in human placenta and cultured trophoblast. Our data indicate that during trophoblast

  6. Blockade of Nicotine and Cannabinoid Reinforcement and Relapse by a Cannabinoid CB1-Receptor Neutral Antagonist AM4113 and Inverse Agonist Rimonabant in Squirrel Monkeys.

    Science.gov (United States)

    Schindler, Charles W; Redhi, Godfrey H; Vemuri, Kiran; Makriyannis, Alexandros; Le Foll, Bernard; Bergman, Jack; Goldberg, Steven R; Justinova, Zuzana

    2016-08-01

    Nicotine, the main psychoactive component of tobacco, and (-)-Δ(9)-tetrahydrocannabinol (THC), the main psychoactive ingredient in cannabis, play major roles in tobacco and marijuana dependence as reinforcers of drug-seeking and drug-taking behavior. Drugs that act as inverse agonists of cannabinoid CB1 receptors in the brain can attenuate the rewarding and abuse-related effects of nicotine and THC, but their clinical use is hindered by potentially serious side effects. The recently developed CB1-receptor neutral antagonists may provide an alternative therapeutic approach to nicotine and cannabinoid dependence. Here we compare attenuation of nicotine and THC reinforcement and reinstatement in squirrel monkeys by the CB1-receptor inverse agonist rimonabant and by the recently developed CB1-receptor neutral antagonist AM4113. Both rimonabant and AM4113 reduced two effects of nicotine and THC that play major roles in tobacco and marijuana dependence: (1) maintenance of high rates of drug-taking behavior, and (2) priming- or cue-induced reinstatement of drug-seeking behavior in abstinent subjects (models of relapse). In contrast, neither rimonabant nor AM4113 modified cocaine-reinforced or food-reinforced operant behavior under similar experimental conditions. However, both rimonabant and AM4113 reduced cue-induced reinstatement in monkeys trained to self-administer cocaine, suggesting the involvement of a common cannabinoid-mediated mechanism in the cue-induced reinstatement for different drugs of abuse. These findings point to CB1-receptor neutral antagonists as a new class of medications for treatment of both tobacco dependence and cannabis dependence. PMID:26888056

  7. Opioid/NMDA receptors blockade reverses the depressant-like behavior of foot shock stress in the mouse forced swimming test.

    Science.gov (United States)

    Haj-Mirzaian, Arya; Ostadhadi, Sattar; Kordjazy, Nastaran; Dehpour, Ahmad Reza; Ejtemaei Mehr, Shahram

    2014-07-15

    Opioid and glutamatergic receptors have a key role in depression following stress. In this study, we assessed opioid and glutamatergic receptors interaction with the depressant-like behavior of acute foot-shock stress in the mouse forced swimming test. Stress was induced by intermittent foot shock stimulation during 30min and swim periods were afterwards conducted by placing mice in separated glass cylinders filled with water for 6min. The immobility time during the last 4min of the test was considered. Acute foot-shock stress significantly increased the immobility time of mice compared to non-stressed control group (P≤0.01). Administration of non-selective opioid receptors antagonist, naltrexone (1 and 2mg/kg, i.p.), and the selective non-competitive NMDA receptor antagonist, MK-801 (0.05mg/kg, i.p.), and the selective serotonin reuptake inhibitor, fluoxetine (5mg/kg), significantly reduced the immobility time in stressed animals (P≤0.01). Lower doses of MK-801 (0.01mg/kg), naltrexone (0.3mg/kg), NMDA (75mg/kg) and morphine(5mg/kg) had no effect on foot-shock stressed mice. Combined treatment of sub-effective doses of naltrexone and MK-801 significantly showed an antidepressant-like effect (P≤0.001). On the other hand, co-administration of non-effective doses of NMDA and morphine with effective doses of naltrexone and MK-801 reversed the anti-immobility effect of these drugs. Taken together, we have for the first time demonstrated the possible role of opioid/NMDA receptors signaling in the depressant-like effect of foot-shock stress, and proposed the use of drugs that act like standard anti-depressants in stress-induced depression.

  8. Alpha and beta adrenergic effects on metabolism in contracting, perfused muscle

    DEFF Research Database (Denmark)

    Richter, Erik; Ruderman, N B; Galbo, H

    1982-01-01

    The role of alpha- and beta-adrenergic receptor stimulation for the effect of epinephrine on muscle glycogenolysis, glucose- and oxygen uptake and muscle performance was studied in the perfused rat hindquarter at rest and during electrical stimulation (60 contractions/min). Adrenergic stimulation...... was obtained by epinephrine in a physiological concentration (2.4 X 10(-8) M) and alpha- and beta-adrenergic blockade by 10(-5) M phentolamine and propranolol, respectively. Epinephrine enhanced net glycogenolysis during contractions most markedly in slow-twitch red fibers. In these fibers the effect...

  9. Polymorphism analysis in estrogen receptors alpha and beta genes and their association with infertile population in Pakistan

    OpenAIRE

    Liaqat, Sinha; Hasnain, Shahida; Muzammil, Saima; Hayat, Sumreen

    2015-01-01

    Studies on polymorphism of estrogen receptor (ESR) alpha and beta genes have been mostly implicated in infertility, but the results have been controversial due to lack of comprehensive data. The present study focused on association of ESR genes with both male and female infertility. In ESRα, PvuII (rs2234693) and XbaI (rs9340799) were studied while in ESRβ gene, risk of infertility was determined for silent G/A RsaI (rs1256049) polymorphism. Total 124 subjects (74 cases and 50 controls) were ...

  10. Effect of Cardiopulmonary Bypass on Beta Adrenergic ReceptorAdenylate Cyclase System on Surfaces of Peripheral Lymphocytes

    Institute of Scientific and Technical Information of China (English)

    LUO Ailin; TIAN Yuke; JIN Shiao

    2000-01-01

    The experimental results showed that the level of CAMP, the ratio of cAPM to cGMP,IL-2R expression and IL-2 production in vitro in lymphocytes immediate and 2 weeks after cardiopulmonary bypass (CPB) were significantly lower than those before anesthetics in the patients undergoing cardiac surgery with CPB. These findings suggested that CPB could cause serious damage to adrenergic beta receptor-adenylate cyclase system on circulating lymphocytes surfaces,which might be one of the mechanisms resulting in immunosuppression after open heart surgery with CPB.

  11. Estrogen receptors alpha and beta in rat placenta: detection by RT-PCR, real time PCR and Western blotting

    Directory of Open Access Journals (Sweden)

    Al-Bader Maie D

    2006-03-01

    Full Text Available Abstract Background High levels of estrogens during pregnancy not only retard placental and fetal growth but can lead to reproductive tract abnormalities in male progeny. Estrogens act through estrogen receptors (ER to modulate the transcription of target genes. These ER exist in two isoforms, ER alpha and ER beta and recently several variants of these isoforms have been identified. Methods The expressions of ER isoforms and variants have been studied in rat placenta at 16, 19 and 21 days gestation (dg. Gene expression was assessed using RT-PCR and real time PCR while protein expression was studied using Western blotting followed by immunodetection. Placental homogenates were probed with: a monoclonal antibody raised against the steroid binding domain of the ER alpha (ER alpha -S, a monoclonal antibody raised against the hinge region of ER alpha (ER alpha -H and a polyclonal antibody raised against the amino terminus of ER beta. Results ER alpha and ER beta mRNA and protein were detected from as early as 16 dg. Two PCR products were detected for ER alpha, one for the wild type ER alpha, and a smaller variant. Real time PCR results suggested the presence of a single product for ER beta. The antibodies used for detection of ER alpha protein both identified a single 67 kDa isoform; however a second 54 kDa band, which may be an ER alpha variant, was identified when using the ER alpha -H antibody. The abundance of both ER alpha bands decreased significantly between 16 and 19 dg. As for ER beta, four bands (76, 59, 54 and 41 kDa were detected. The abundance of the 59 and 54 kDa bands decreased significantly between 16 and 19 dg. Conclusion This study shows that both ER protein isoforms and their variants are present in rat placenta. The decrease in their expression near parturition suggests that the placenta may be relatively unresponsive to estrogens at this stage.

  12. Validation study of a receptor-based lateral flow assay for detection of beta-lactam antibiotics in milk.

    Science.gov (United States)

    Abouzied, Mohamed; Sarzynski, Michael; Walsh, Aaron; Wood, Heather; Mozola, Mark

    2009-01-01

    A validation study designed to meet the requirements of the AOAC Research Institute and the U.S. Food and Drug Administration (FDA), Center for Veterinary Medicine, was conducted for a receptor-based, immunochromatographic method (BetaStar US) for detection of beta-lactam antibiotic residues in raw, commingled bovine milk. The assay was found to detect amoxicillin, ampicillin, cephapirin, cloxacillin, and penicillin G at levels below the FDA tolerance/safe levels but above the maximum sensitivity thresholds established by the National Conference on Interstate Milk Shipments. Results of the Part I (internal) and Part II (independent laboratory) dose-response studies using spiked samples were in very close agreement for all five drugs tested, with differences between the Part I and Part II 90/95% sensitivity values ranging from 0 to 1 ppb. The test was able to detect all five drugs at the approximate 90/95% sensitivity levels when present as incurred residues in milk collected from cows that had been treated with the specific drug. A sixth drug, ceftiofur, was found to be undetectable at levels of 1000 control milk samples. The assay was found to be applicable to the testing of frozen raw milk samples. Results of ruggedness experiments established the operating parameter tolerances for the BetaStar US assay. Results of cross-reactivity testing established that the assay detects certain other beta-lactam drugs (dicloxacillin and ticarcillin), but it does not cross-react with any of 30 drugs belonging to other classes. Abnormally high bacterial or somatic cell counts in raw milk produced no interference with the ability of the test to detect beta-lactams at tolerance/safe levels. PMID:19610391

  13. Molecular Characterization and Sex-Specific Tissue Expression of Estrogen Receptor Alpha (esr1), Estrogen Receptor Beta-a (esr2a) and Ovarian Aromatase (cyp19a1a) in Yellow Perch (Perca flavescens)

    Science.gov (United States)

    Yellow perch (Perca flavescens) exhibit an estrogen-stimulated sexual size dimorphism (SSD) wherein females grow faster and larger than males. To aid in the examination of this phenomenon, the cDNA sequences encoding estrogen receptor-alpha (esr1), estrogen receptor-beta-a (esr2a) and ovarian aroma...

  14. 17-Beta-estradiol inhibits transforming growth factor-beta signaling and function in breast cancer cells via activation of extracellular signal-regulated kinase through the G protein-coupled receptor 30.

    Science.gov (United States)

    Kleuser, Burkhard; Malek, Daniela; Gust, Ronald; Pertz, Heinz H; Potteck, Henrik

    2008-12-01

    Breast cancer development and breast cancer progression involves the deregulation of growth factors leading to uncontrolled cellular proliferation, invasion and metastasis. Transforming growth factor (TGF)-beta plays a crucial role in breast cancer because it has the potential to act as either a tumor suppressor or a pro-oncogenic chemokine. A cross-communication between the TGF-beta signaling network and estrogens has been postulated, which is important for breast tumorigenesis. Here, we provide evidence that inhibition of TGF-beta signaling is associated with a rapid estrogen-dependent nongenomic action. Moreover, we were able to demonstrate that estrogens disrupt the TGF-beta signaling network as well as TGF-beta functions in breast cancer cells via the G protein-coupled receptor 30 (GPR30). Silencing of GPR30 in MCF-7 cells completely reduced the ability of 17-beta-estradiol (E2) to inhibit the TGF-beta pathway. Likewise, in GPR30-deficient MDA-MB-231 breast cancer cells, E2 achieved the ability to suppress TGF-beta signaling only after transfection with GPR30-encoding plasmids. It is most interesting that the antiestrogen fulvestrant (ICI 182,780), which possesses agonistic activity at the GPR30, also diminished TGF-beta signaling. Further experiments attempted to characterize the molecular mechanism by which activated GPR30 inhibits the TGF-beta pathway. Our results indicate that GPR30 induces the stimulation of the mitogen-activated protein kinases (MAPKs), which interferes with the activation of Smad proteins. Inhibition of MAPK activity prevented the ability of E2 from suppressing TGF-beta signaling. These findings are of great clinical relevance, because down-regulation of TGF-beta signaling is associated with the development of breast cancer resistance in response to antiestrogens.

  15. Chromosomal translocation involving the beta T cell receptor gene in acute leukemia

    OpenAIRE

    1988-01-01

    DNA spanning a t(7;19) chromosomal translocation breakpoint was isolated from the human T cell line SUP-T7 established from an acute lymphoblastic leukemia. Nucleotide sequence analysis showed that the point of crossover on chromosome 7 occurred immediately adjacent to joining segment J beta 1.1 within the TCR-beta gene, suggesting that this translocation resulted from an error in TCR gene rearrangement. On chromosome 19, the translocation occurred within a previously uncharacterized transcri...

  16. Structure of the T-cell receptor in a Ti alpha beta, Ti gamma delta double positive T-cell line

    DEFF Research Database (Denmark)

    Kuhlmann, J; Geisler, C

    1993-01-01

    is still not known. It has been suggested that each T-cell receptor contains two Ti dimers. To gain insight into the structure of the T-cell receptor we constructed a Ti alpha beta, Ti gamma delta double positive T-cell line which contained four functional Ti chains (Ti alpha, beta, gamma, and delta......The multichain T-cell receptor is composed of at least six different polypeptide chains. The clonotypic Ti heterodimer (Ti alpha beta or Ti gamma delta) is non-covalently associated with the CD3 chains (CD3 gamma delta epsilon zeta). The exact number of subunits constituting the T-cell receptor......). The data demonstrated an absence of Ti dimers containing mixtures of chains other than the typical Ti alpha beta and Ti gamma delta combinations. Furthermore, by co-modulation experiments we demonstrated that the Ti alpha beta and the Ti gamma delta dimers were not expressed in the same T-cell receptor...

  17. Blockade of prostaglandin E2 signaling through EP1 and EP3 receptors attenuates Flt3L-dependent dendritic cell development from hematopoietic progenitor cells

    Science.gov (United States)

    Singh, Pratibha; Hoggatt, Jonathan; Hu, Peirong; Speth, Jennifer M.; Fukuda, Seiji; Breyer, Richard M.

    2012-01-01

    Dendritic cell (DC) homeostasis, like all mature blood cells, is maintained via hierarchal generation from hematopoietic precursors; however, little is known about the regulatory mechanisms governing DC generation. Here, we show that prostaglandin E2 (PGE2) is required for optimal Flt3 ligand–mediated DC development and regulates expression of the Flt3 receptor on DC-committed progenitor cells. Inhibition of PGE2 biosynthesis reduces Flt3-mediated activation of STAT3 and expression of the antiapoptotic protein survivin, resulting in increased apoptosis of DC-committed progenitor cells. Reduced DC development caused by diminished PGE2 signaling is reversed by overexpression of Flt3 or survivin in DC progenitors and conversely is mimicked by STAT3 inhibition. PGE2 regulation of DC generation is specifically mediated through the EP1 and EP3 G protein PGE2 receptors. These studies define a novel DC progenitor regulatory pathway in which PGE2 signaling through EP1/EP3 receptors regulates Flt3 expression and downstream STAT3 activation and survivin expression, required for optimal DC progenitor survival and DC development in vivo. PMID:22110249

  18. Effects of AT1 Receptor Blockade on Plasma Thromboxane A2 (TXA2 Level and Skin Microcirculation in Young Healthy Women on Low Salt Diet

    Directory of Open Access Journals (Sweden)

    Ana Cavka

    2013-10-01

    Full Text Available Objective: To determine the effect of AT1 receptor antagonism on skin microcirculation and plasma level of thromboxane A2 (TXA2. Methods: Healthy women (n=20 maintained 7 days low salt (LS diet (intake 2 metabolite thromboxane B2 (TXB2 and plasma renin activity (PRA aldosterone concentration, electrolytes (Na+, K+, as well as blood pressure and heart rate were determined before and after study protocols. Results: PRA and aldosterone increased significantly after 7 days of both LS diet and LS diet+losartan. LS diet or LS diet+losartan administrations had no significant effect on post-occlusion hyperemia While there was no change in TXB2 after LS diet TXB2 significantly increased after one week of LS+losartan compared to control levels (cTXB2 pg/mL control 101±80 vs. LS diet+losartan 190±116, pConclusion: These data suggest that inhibition of AT1 receptors could lead to activation of AT2 receptors, which maintain hyperemia, despite the increased level of vasoconstrictor TXA2. These findings also suggest an important role of crosstalk between renin-angiotensin system (RAS and arachidonic acid metabolites in the regulation of microcirculation under physiological conditions.

  19. Blockade of insulin-like growth factor type-1 receptor with cixutumumab (IMC-A12): a novel approach to treatment for multiple cancers.

    Science.gov (United States)

    Rowinsky, Eric K; Schwartz, Jonathan D; Zojwalla, Naseem; Youssoufian, Hagop; Fox, Floyd; Pultar, Philippe; Novosyadlyy, Ruslan; Cosaert, Jan; Ludwig, Dale L

    2011-12-01

    Insulin-like growth factor type-1 receptor (IGF-1R) plays a central role in cell proliferation and survival and is overexpressed in many tumor types. Notably, IGF-1R-mediated signaling confers resistance to diverse cytotoxic, hormonal, and biologic agents, suggesting that therapies targeting IGF-1R may be effective against a broad range of human malignancies. Cixutumumab (IMC-A12; ImClone Systems) is a fully human immunoglobulin G1 (IgG1) monoclonal antibody that specifically inhibits IGF-1R signaling. Binding of cixutumumab to IGF-1R results in receptor internalization and degradation. Because cixutumumab is an IgG1 monoclonal antibody, it may induce additional cytotoxicity via immune effector mechanisms such as antibody-dependent cellular cytotoxicity. In preclinical studies, cixutumumab monotherapy resulted in growth inhibition of multiple experimental cancers. Moreover, cixutumumab safely enhanced the tumor growth inhibitory and cytotoxic effects of a broad range of chemotherapeutics, and modulated the action of agents that target hormone receptors and signal transduction, which may have implications for cancer therapy. Herein, we review published preclinical and clinical data for cixutumumab and provide a comprehensive overview of selected clinical studies.

  20. Pancreatic Beta Cell G-Protein Coupled Receptors and Second Messenger Interactions: A Systems Biology Computational Analysis.

    Science.gov (United States)

    Fridlyand, Leonid E; Philipson, Louis H

    2016-01-01

    Insulin secretory in pancreatic beta-cells responses to nutrient stimuli and hormonal modulators include multiple messengers and signaling pathways with complex interdependencies. Here we present a computational model that incorporates recent data on glucose metabolism, plasma membrane potential, G-protein-coupled-receptors (GPCR), cytoplasmic and endoplasmic reticulum calcium dynamics, cAMP and phospholipase C pathways that regulate interactions between second messengers in pancreatic beta-cells. The values of key model parameters were inferred from published experimental data. The model gives a reasonable fit to important aspects of experimentally measured metabolic and second messenger concentrations and provides a framework for analyzing the role of metabolic, hormones and neurotransmitters changes on insulin secretion. Our analysis of the dynamic data provides support for the hypothesis that activation of Ca2+-dependent adenylyl cyclases play a critical role in modulating the effects of glucagon-like peptide 1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and catecholamines. The regulatory properties of adenylyl cyclase isoforms determine fluctuations in cytoplasmic cAMP concentration and reveal a synergistic action of glucose, GLP-1 and GIP on insulin secretion. On the other hand, the regulatory properties of phospholipase C isoforms determine the interaction of glucose, acetylcholine and free fatty acids (FFA) (that act through the FFA receptors) on insulin secretion. We found that a combination of GPCR agonists activating different messenger pathways can stimulate insulin secretion more effectively than a combination of GPCR agonists for a single pathway. This analysis also suggests that the activators of GLP-1, GIP and FFA receptors may have a relatively low risk of hypoglycemia in fasting conditions whereas an activator of muscarinic receptors can increase this risk. This computational analysis demonstrates that study of second messenger

  1. The low-density lipoprotein receptor-related protein 10 is a negative regulator of the canonical Wnt/{beta}-catenin signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Young-Hee; Sekiya, Manami; Hirata, Michiko; Ye, Mingjuan; Yamagishi, Azumi [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan); Lee, Sang-Mi; Kang, Man-Jong [Department of Animal Science, College of Agriculture and Life Science, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Hosoda, Akemi; Fukumura, Tomoe; Kim, Dong-Ho [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan); Saeki, Shigeru, E-mail: saeki@life.osaka-cu.ac.jp [Department of Molecular and Biochemical Nutrition, Graduate School of Human Life Science, Osaka City University, Osaka 558-8585 (Japan)

    2010-02-19

    Wnt signaling pathways play fundamental roles in the differentiation, proliferation and functions of many cells as well as developmental, growth, and homeostatic processes in animals. Low-density lipoprotein receptor (LDLR)-related protein (LRP) 5 and LRP6 serve as coreceptors of Wnt proteins together with Frizzled receptors, triggering activation of canonical Wnt/{beta}-catenin signaling. Here, we found that LRP10, a new member of the LDLR gene family, inhibits the canonical Wnt/{beta}-catenin signaling pathway. The {beta}-catenin/T cell factor (TCF) transcriptional activity in HEK293 cells was activated by transfection with Wnt3a or LRP6, which was then inhibited by co-transfection with LRP10. Deletion of the extracellular domain of LRP10 negated its inhibitory effect. The inhibitory effect of LRP10 was consistently conserved in HEK293 cells even when GSK3{beta} phosphorylation was inhibited by incubation with lithium chloride and co-transfection with constitutively active S33Y-mutated {beta}-catenin. Nuclear {beta}-catenin accumulation was unaffected by LRP10. The present studies suggest that LRP10 may interfere with the formation of the {beta}-catenin/TCF complex and/or its binding to target DNA in the nucleus, and that the extracellular domain of LRP10 is critical for inhibition of the canonical Wnt/{beta}-catenin signaling pathway.

  2. Influence of Angiotensin II Subtype 2 Receptor (AT2R Antagonist, PD123319, on Cardiovascular Remodelling of Aged Spontaneously Hypertensive Rats during Chronic Angiotensin II Subtype 1 Receptor (AT1R Blockade

    Directory of Open Access Journals (Sweden)

    Emma S. Jones

    2012-01-01

    Adult (20 weeks and senescent (20 months spontaneously hypertensive rats (SHRs were treated with either the AT1R antagonist, candesartan cilexetil (2 mg/kg/day, the AT2R antagonist, PD123319 (10 mg/kg/day, or a combination of the 2 compounds. Mean arterial pressure (MAP and left ventricular volume were markedly decreased by candesartan cilexetil, however, simultaneous treatment with PD123319 had no additional effect on either parameter. Perivascular fibrosis was significantly reduced by candesartan cilexetil in aged animals only, and this effect was reversed by concomitant PD123319 administration. Vascular hypertrophy was reduced by candesartan cilexetil, and these effects were reversed by simultaneous PD123319. These results suggest that AT2R stimulation does not significantly influence the antihypertensive effect of chronic AT1R blockade, but plays a role in the regulation of vascular structure. The severe degree of cardiac perivascular fibrosis in senescent animals was regressed by AT1R blockade and this effect was reversed by simultaneous AT2R inhibition, demonstrating an antifibrotic role of AT2R stimulation in the aging hypertensive heart.

  3. Blockade of NK-1 receptors in the lateral commissural nucleus tractus solitarii of awake rats had no effect on the cardiovascular responses to chemoreflex activation

    Directory of Open Access Journals (Sweden)

    Zhang C.

    2000-01-01

    Full Text Available The neurotransmission of the chemoreflex in the nucleus tractus solitarii (NTS, particularly of the sympatho-excitatory component, is not completely understood. There is evidence that substance P may play a role in the neurotransmission of the chemoreflex in the NTS. Microinjection of substance P (50 pmol/50 nl, N = 12, and 5 nmol/50 nl, N = 8 into the commissural NTS of unanesthetized rats produced a significant increase in mean arterial pressure (101 ± 1 vs 108 ± 2 and 107 ± 3 vs 115 ± 4 mmHg, respectively and no significant changes in heart rate (328 ± 11 vs 347 ± 15 and 332 ± 7 vs 349 ± 13 bpm, respectively 2 min after microinjection. Previous treatment with WIN, an NK-1 receptor antagonist (2.5 nmol/50 nl, microinjected into the NTS of a specific group of rats, blocked the pressor (11 ± 5 vs 1 ± 2 mmHg and tachycardic (31 ± 6 vs 4 ± 3 bpm responses to substance P (50 pmol/50 nl, N = 5 observed 10 min after microinjection. Bilateral microinjection of WIN into the lateral commissural NTS (N = 8 had no significant effect on the pressor (50 ± 4 vs 42 ± 6 mmHg or bradycardic (-230 ± 16 vs -220 ± 36 bpm responses to chemoreflex activation with potassium cyanide (iv. These data indicate that the activation of NK-1 receptors by substance P in the NTS produces an increase in baseline mean arterial pressure and heart rate. However, the data obtained with WIN suggest that substance P and NK-1 receptors do not play a major role in the neurotransmission of the chemoreflex in the lateral commissural NTS.

  4. BLOCKADE OF ROSTRAL VENTROLATERAL MEDULLA (RVLM BOMBESIN RECEPTOR TYPE 1 DECREASES BLOOD PRESSURE AND SYMPATHETIC ACTIVITY IN ANESTHETIZED SPONTANEOUSLY HYPERTENSIVE RATS

    Directory of Open Access Journals (Sweden)

    Izabella Silva De Jesus Pinto

    2016-06-01

    Full Text Available IIntrathecal injection of bombesin (BBS promoted hypertensive and sympathoexcitatory effects in normotensive (NT rats. However, the involvement of rostral ventrolateral medulla (RVLM in these responses is still unclear. In the present study, we investigated: (1 the effects of BBS injected bilaterally into RVLM on cardiorespiratory and sympathetic activity in NT and spontaneously hypertensive rats (SHR; (2 the contribution of RVLM bombesin type 1 receptors (BB1 to the maintenance of hypertension in SHR. Urethane-anesthetized rats (1.2 g · kg−1, i.v. were instrumented to record mean arterial pressure (MAP, diaphragm (DIA motor and renal sympathetic nerve activity (RSNA. In NT rats and SHR, BBS (0.3 mM nanoinjected into RVLM increased MAP (33.9 ± 6.6 mmHg and 37.1 ± 4.5 mmHg, respectively; p < 0.05 and RSNA (97.8 ± 12.9 % and 84.5 ± 18.1 %, respectively; p < 0.05. In SHR, BBS also increased DIA burst amplitude (115.3 ± 22.7 %; p < 0.05. BB1 receptors antagonist (BIM-23127; 3 mM reduced MAP (-19.9 ± 4.4 mmHg; p < 0.05 and RSNA (-17.7 ± 3.8 %; p < 0.05 in SHR, but not in NT rats (-2.5 ± 2.8 mmHg; -2.7 ± 5.6 %, respectively. These results show that BBS can evoke sympathoexcitatory and pressor responses by activating RVLM BB1 receptors. This pathway might be involved in the maintenance of high levels of arterial blood pressure in SHR.

  5. Combined stimulation of the glycine and polyamine sites of the NMDA receptor attenuates NMDA blockade-induced learning deficits of rats in a 14-unit T-maze.

    Science.gov (United States)

    Meyer, R C; Knox, J; Purwin, D A; Spangler, E L; Ingram, D K

    1998-02-01

    The present study examined the effects of multi-site activation of the glycine and polyamine sites of the NMDA receptor on memory formation in rats learning a 14-unit T-maze task. The competitive NMDA receptor antagonist, (+/-)-3-(2-carboxypiperazine-4-yl)-propyl-1-phosphonic acid (CPP, 9 mg/kg), was used to impair learning. The objectives were two-fold: (1) to investigate the effects of independent stimulation of the strychnine-insensitive glycine site or the polyamine site; (2) to investigate the effects of simultaneous activation of these two sites. Male, Fischer-344 rats were pretrained to a criterion of 13 out of 15 shock avoidances in a straight runway, and 24 h later were trained in a 14-unit T-maze that also required shock avoidance. Prior to maze training, rats received intraperitoneal (i.p.) injections of saline, saline plus CPP, CPP plus the glycine agonist, D-cycloserine (DCS, 30 or 40 mg/kg), CPP plus the polyamine agonist, spermine (SPM, 2.5 or 5 mg/kg), or CPP plus a combination of DCS (7.5 mg/kg) and SPM (0.625 mg/kg). Individual administration of either DCS or SPM attenuated the CPP-induced maze learning impairment in a dose-dependent manner. However, the combined treatment with both DCS and SPM completely reversed the learning deficit at doses five-fold less than either drug given alone. These findings provide additional evidence that the glycine and polyamine modulatory sites of the NMDA receptor are involved in memory formation. Furthermore, the potent synergistic effect resulting from combined activation of the glycine and polyamine sites would suggest a stronger interaction between these two sites than previously considered, and might provide new therapeutic approaches for enhancing glutamatergic function. PMID:9498733

  6. HLA-DR, DQ and T cell antigen receptor constant beta genes in Japanese patients with ulcerative colitis.

    Science.gov (United States)

    Kobayashi, K; Atoh, M; Konoeda, Y; Yagita, A; Inoko, H; Sekiguchi, S

    1990-01-01

    We studied the T cell antigen receptor (TcR) constant beta chain genes on HLA typed Japanese patients with ulcerative colitis (UC). A TcR constant beta EcoRI 6.0-kb fragment was present in all Japanese UC patients (n = 17) but completely absent in the controls (n = 35) (chi2 = 47.6, P less than 0.001). The frequency of HLA-DR2 antigen was significantly higher in UC patients (85% versus 28% in controls, P less than 0.001). Furthermore, HLA-DQw1 antigen was also increased in UC patients (96% versus 60% in controls, P less than 0.001). However, HLA-DR4 antigen was significantly decreased in UC patients (12% versus 37%, P = 0.02). HLA-DR1 antigen was not found in UC patients and was present in only 15% of the controls. These results suggest that TcR beta chain and HLA-DQw1 antigen may be important in the pathogenesis of Japanese UC. Images Fig. 1 PMID:1973647

  7. Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.

    Science.gov (United States)

    Powell, Susan A; Smith, Bradford B; Timm, Karen I; Menino, Alfred R

    2007-08-01

    Because estrogen may be involved in maternal recognition of pregnancy and embryonic migration in llamas, expression of estrogen receptor subtypes alpha (ERalpha) and beta (ERbeta) was evaluated in corpus luteum (CL), endometrium, and uterus using relative RT-PCR. Tissues were recovered from sterile-mated (SM) and pregnant (PG) females during Days 7-11 and 7-13 (Day 0 = day of mating), respectively, and follicular phase and juvenile females. Luteal expression of ERalpha and beta was similar (P > 0.10) in SM and PG females and within Days 7-11, however, expression of ERalpha in ovarian tissue from follicular phase females was greater (P Uterus expressed less ERalpha and beta compared to endometrium (P = 0.07 and P 0.10) between SM and PG females or by day. The presence of luteal ER during this period may mean a role for estradiol in maternal recognition of pregnancy. Observed increases in uterine ER expression with no changes in endometrium suggest expression increased in myometrium and/or perimetrium. Upregulation of myometrial ERbeta in PG females may be involved in supporting uterine migration of the embryo. PMID:17219432

  8. Pet measurements of postsynaptic muscarinic and beta adrenergic receptors in the heart

    International Nuclear Information System (INIS)

    There is ample evidence from both experimental and clinical studies that changes in β-adrenergic and muscarinic receptor density can be associated with such cardiac diseases as congestive heart failure, myocardial ischemia and infarction, cardiomyopathy, diabetes, or thyroid-induced muscle disease. Changes in B-adrenergic density also have been shown in the denervated transplanted heart. These alterations of cardiac receptors have been demonstrated in vitro on homogenates from samples collected mainly during surgery or post mortem. Recent developments of Positron Emission Tomography (PET) techniques and of radioligands suitable for cardiac receptor binding studies in vivo have made possible both the imaging and the measurement of receptor density. From these studies, important information is now available concerning physiologic and pathologic conditions, as well as alterations induced by treatment. For the investigation of myocardial B-adrenergic receptors we have used [11C] CGP 12177, a potent hydrophilic antagonist of the 3-adrenergic receptor. The quantification of myocardial muscarinic receptors in vivo has been obtained with [11C] MQNB, a nonmetabolized hydrophilic antagonist of the muscarinic receptor. Receptor density and affinity have been measured by a kinetic, nonequilibrium approach in an experimental protocol that provides sufficient data to determine values for all parameters from a single experiment

  9. Blockade of the interleukin-2 receptor by anti-Tac antibody inhibits the generation of antigen-nonspecific suppressor T cells in vitro.

    OpenAIRE

    Oh-Ishi, T; Goldman, C K; Misiti, J; Waldmann, T. A.

    1988-01-01

    The role of interleukin 2 (IL-2) in the activation of suppressor T cells was investigated by using the monoclonal antibody anti-Tac, which blocks the binding of IL-2 to the 55-kDa peptide of the high-affinity IL-2 receptor. Anti-Tac was added to an antigen-nonspecific suppressor system in which Con A-induced suppressor T cells were generated during a preculture period, and their effects on immunoglobulin production were assessed in second, indicator cultures containing pokeweed mitogen and pe...

  10. Pavlovian conditioning of morphine-induced alterations of immune status: evidence for peripheral beta-adrenergic receptor involvement.

    Science.gov (United States)

    Coussons-Read, M E; Dykstra, L A; Lysle, D T

    1994-09-01

    The present studies examined the involvement of peripheral beta-adrenergic receptor activity in the establishment and expression of conditioned morphine-induced alterations of immune status. Previous work in our laboratory has shown that morphine's immunomodulatory effects can become conditioned to environmental stimuli which predict drug administration. These immune alterations include conditioned changes in natural killer cell activity, interleukin-2 production, and mitogen-induced lymphocyte proliferation. During the training phase of these experiments, Lewis rats received two conditioning sessions during which a subcutaneous injection of 15 mg/kg morphine sulfate was paired with exposure to a distinctive environment. On the test day, rats were reexposed to the conditioned stimulus prior to sacrifice. Saline or nadolol (0.002, 0.02, 0.2, or 2.0 mg/kg) was administered either prior to the training sessions or prior to the test session. Administration of nadolol prior to training did not affect the development of conditioned alterations of immune status. Conversely, nadolol administration prior to testing completely attenuated the expression of a subset of the conditioned morphine-induced changes in immune status. Taken together, these studies suggest that whereas peripheral beta-adrenergic receptor activity is not required for the establishment of conditioned morphine-induced alterations of immune status, it is involved in the expression of a subset of these conditioned immunomodulatory effects.

  11. Interferon beta and vitamin D synergize to induce immunoregulatory receptors on peripheral blood monocytes of multiple sclerosis patients.

    Directory of Open Access Journals (Sweden)

    Anne Waschbisch

    Full Text Available Immunoglobulin-like transcript (ILT 3 and 4 are inhibitory receptors that modulate immune responses. Their expression has been reported to be affected by interferon, offering a possible mechanism by which this cytokine exerts its therapeutic effect in multiple sclerosis, a condition thought to involve excessive immune activity. To investigate this possibility, we measured expression of ILT3 and ILT4 on immune cells from multiple sclerosis patients, and in post-mortem brain tissue. We also studied the ability of interferon beta, alone or in combination with vitamin D, to induce upregulation of these receptors in vitro, and compared expression levels between interferon-treated and untreated multiple sclerosis patients. In vitro interferon beta treatment led to a robust upregulation of ILT3 and ILT4 on monocytes, and dihydroxyvitamin D3 increased expression of ILT3 but not ILT4. ILT3 was abundant in demyelinating lesions in postmortem brain, and expression on monocytes in the cerebrospinal fluid was higher than in peripheral blood, suggesting that the central nervous system milieu induces ILT3, or that ILT3 positive monocytes preferentially enter the brain. Our data are consistent with involvement of ILT3 and ILT4 in the modulation of immune responsiveness in multiple sclerosis by both interferon and vitamin D.

  12. 5-HT(2C) serotonin receptor blockade prevents tau protein hyperphosphorylation and corrects the defect in hippocampal synaptic plasticity caused by a combination of environmental stressors in mice.

    Science.gov (United States)

    Busceti, Carla Letizia; Di Pietro, Paola; Riozzi, Barbara; Traficante, Anna; Biagioni, Francesca; Nisticò, Robert; Fornai, Francesco; Battaglia, Giuseppe; Nicoletti, Ferdinando; Bruno, Valeria

    2015-09-01

    Exposure to multimodal sensory stressors is an everyday occurrence and sometimes becomes very intense, such as during rave parties or other recreational events. A growing body of evidence suggests that strong environmental stressors might cause neuronal dysfunction on their own in addition to their synergistic action with illicit drugs. Mice were exposed to a combination of physical and sensory stressors that are reminiscent of those encountered in a rave party. However, this is not a model of rave because it lacks the rewarding properties of rave. A 14-h exposure to environmental stressors caused an impairment of hippocampal long-term potentiation (LTP) and spatial memory, and an enhanced phosphorylation of tau protein in the CA1 and CA3 regions. These effects were transient and critically depended on the activation of 5-HT2C serotonin receptors, which are highly expressed in the CA1 region. Acute systemic injection of the selective 5-HT2C antagonist, RS-102,221 (2 mg/kg, i.p., 2 min prior the onset of stress), prevented tau hyperphosphorylation and also corrected the defects in hippocampal LTP and spatial memory. These findings suggest that passive exposure to a combination of physical and sensory stressors causes a reversible hippocampal dysfunction, which might compromise mechanisms of synaptic plasticity and spatial memory for a few days. Drugs that block 5-HT2C receptors might protect the hippocampus against the detrimental effect of environmental stressors. PMID:26145279

  13. Blockade of Rostral Ventrolateral Medulla (RVLM) Bombesin Receptor Type 1 Decreases Blood Pressure and Sympathetic Activity in Anesthetized Spontaneously Hypertensive Rats.

    Science.gov (United States)

    Pinto, Izabella S; Mourão, Aline A; da Silva, Elaine F; Camargo, Amanda S; Marques, Stefanne M; Gomes, Karina P; Fajemiroye, James O; da Silva Reis, Angela A; Rebelo, Ana C S; Ferreira-Neto, Marcos L; Rosa, Daniel A; Freiria-Oliveira, André H; Castro, Carlos H; Colombari, Eduardo; Colugnati, Diego B; Pedrino, Gustavo R

    2016-01-01

    Intrathecal injection of bombesin (BBS) promoted hypertensive and sympathoexcitatory effects in normotensive (NT) rats. However, the involvement of rostral ventrolateral medulla (RVLM) in these responses is still unclear. In the present study, we investigated: (1) the effects of BBS injected bilaterally into RVLM on cardiorespiratory and sympathetic activity in NT and spontaneously hypertensive rats (SHR); (2) the contribution of RVLM BBS type 1 receptors (BB1) to the maintenance of hypertension in SHR. Urethane-anesthetized rats (1.2 g · kg(-1), i.v.) were instrumented to record mean arterial pressure (MAP), diaphragm (DIA) motor, and renal sympathetic nerve activity (RSNA). In NT rats and SHR, BBS (0.3 mM) nanoinjected into RVLM increased MAP (33.9 ± 6.6 and 37.1 ± 4.5 mmHg, respectively; p BIM-23127; 3 mM) reduced MAP (-19.9 ± 4.4 mmHg; p < 0.05) and RSNA (-17.7 ± 3.8%; p < 0.05) in SHR, but not in NT rats (-2.5 ± 2.8 mmHg; -2.7 ± 5.6%, respectively). These results show that BBS can evoke sympathoexcitatory and pressor responses by activating RVLM BB1 receptors. This pathway might be involved in the maintenance of high levels of arterial blood pressure in SHR. PMID:27313544

  14. Long-term exposure to IL-1beta enhances Toll-IL-1 receptor-mediated inflammatory signaling in murine airway hyperresponsiveness

    DEFF Research Database (Denmark)

    Zhang, Yaping; Xu, Cang-Bao; Cardell, Lars-Olaf

    2009-01-01

    Toll-interleukin-1 (Toll-IL-1) receptor signaling may play a key role in the development of airway hyperreactivity (AHR) and chronic airway inflammatory diseases such as asthma. Previously, we have demonstrated that pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha) and interleukin......RNA expression following IL-1beta treatment. Immunohistochemistry confirmed that protein expression for CD14, RP105, MCP-1 and phosphorylated IkappaB-alpha were increased in both the airway epithelial and smooth muscle cells. In order to link the activation of Toll-IL-1 receptor-mediated inflammatory signal......-1beta (IL-1beta), induce AHR. However, the underlying intracellular signaling mechanisms that lead to AHR remain elusive. In order to see if the Toll-IL-1 receptor-mediated inflammatory signal pathways are involved in the development of AHR, the present study was designed to use a real-time PCR...

  15. Expression of glucocorticoid receptor, mineralocorticoid receptor, and 11beta-hydroxysteroid dehydrogenase 1 and 2 in the fetal and postnatal ovine hippocampus: ontogeny and effects of prenatal glucocorticoid exposure.

    Science.gov (United States)

    Sloboda, Deborah M; Moss, Timothy J M; Li, Shaofu; Matthews, Stephen G; Challis, John R G; Newnham, John P

    2008-05-01

    To determine the expression of glucocorticoid metabolizing and action genes in the hippocampus of fetal, neonatal, and adult sheep. Pregnant ewes (or their fetuses) received intramuscular injections of saline or betamethasone (BETA, 0-5 mg/kg) at 104, 111, 118, and/or 125 days of gestation (dG). Hippocampal tissue was collected prior to (75, 84, and 101 dG), during (109 and 116 dG), or after (121, 132, and 146 dG; 6 and 12 postnatal weeks; 3.5 years of age) saline or BETA injections. Hippocampal glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and 11beta-hydroxysteroid dehydrogenase (11betaHSD)1 and 11betaHSD2 mRNA levels were determined using qRT-PCR. Control animals late in gestation demonstrated a decrease in mRNA encoding GR and 11betaHSD1, whereas 11betaHSD2 was undetectable, consistent with a damping of the negative feedback influence of circulating or locally produced cortisol on the hypothalamic-pituitary-adrenal (HPA) axis. BETA-administration had transient effects on fetal GR and MR, and early in postnatal life (12 weeks of age) 11betaHSD1 mRNA was increased. Hippocampal MR mRNA was elevated in adult offspring exposed to either one or four doses of maternal BETA (Pglucocorticoid negative feedback, facilitating increased preterm HPA activity and parturition. Adult offspring of BETA-treated mothers demonstrated increased MR and 11betaHSD2 mRNA, therefore it appears that exposure of fetus to high levels of synthetic glucocorticoids may have long-lasting effects on the hippocampal expression of HPA-related genes into adulthood.

  16. Blockade of the locomotor stimulant effects of amphetamine by group I, group II, and group III metabotropic glutamate receptor ligands in the rat nucleus accumbens: possible interactions with dopamine receptors.

    Science.gov (United States)

    David, H N; Abraini, J H

    2003-05-01

    Previous investigations have shown that mGlu receptors would be involved in the amphetamine-induced motor response. However, data are somewhat controversial across studies where methodological protocols vary. The aim of the present study was to determine the involvement of mGlu receptors in the NAcc in the locomotor-activating properties of amphetamine in rats well habituated to their experimental environment, a condition known to modulate the motor response to amphetamine. Focal infusion of the group I mGlu receptor antagonist S-4-CPG, which has no effect on basal motor activity, virtually suppressed the locomotor response to amphetamine, while infusion of the group II mGlu receptor antagonist LY 341495 or the group III mGlu receptor agonist AP4, at the minimal dose that produces locomotor activation, reduced it by approximately a half. These effects were blocked by the group I mGlu receptor agonist DHPG, the group II mGlu receptor agonist APDC, and the group III mGlu receptor antagonist MPPG, respectively. These data confirm that mGlu receptors in the NAcc contribute to the psychostimulant motor effect of amphetamine. Results are discussed from the view of recent neuropharmacological studies that have defined the effects of these mGlu receptor ligands on basal motor activity and DA receptor agonists-induced locomotor responses in rats exposed to similar experimental procedures (Eur J Neuroscience 13 (2001) 2157; Neuropharmacology 41 (2001) 454; Eur J Neuroscience 13 (2001) 869). It is suggested that the contribution of mGlu receptors to the amphetamine-induced motor response may result mainly from their functional, either direct or indirect, interactions with D1-like receptors in the NAcc. PMID:12681370

  17. Angiotensin receptor blockade in acute stroke. The Scandinavian Candesartan Acute Stroke Trial: rationale, methods and design of a multicentre, randomised- and placebo-controlled clinical trial (NCT00120003)

    DEFF Research Database (Denmark)

    Sandset, Else Charlotte; Murray, Gordon; Boysen, Gudrun Margrethe;

    2010-01-01

    Elevated blood pressure following acute stroke is common, and yet early antihypertensive treatment is controversial. ACCESS suggested a beneficial effect of the angiotensin receptor blocker candesartan in the acute phase of stroke, but these findings need to be confirmed in new, large trials. AIM...... variables: Secondary effect variables include • the Barthel index (functional status) • EuroQol (quality of life) and • Mini-mental state examination (cognition) at 6-months • Health economic costs during the first 6-months......, Sweden, Denmark, Belgium, Germany, Poland, Lithuania, Estonia and Finland. STUDY OUTCOMES: There are two co-primary effect variables: • Functional status at 6-months, measured by the modified Rankin Scale, and • vascular death, myocardial infarction or stroke during the first 6-months. Secondary outcome...

  18. Blockade of tumor necrosis factor (TNF) receptor type 1-mediated TNF-alpha signaling protected Wistar rats from diet-induced obesity and insulin resistance.

    Science.gov (United States)

    Liang, Huifang; Yin, Bingjiao; Zhang, Hailong; Zhang, Shu; Zeng, Qingling; Wang, Jing; Jiang, Xiaodan; Yuan, Li; Wang, Cong-Yi; Li, Zhuoya

    2008-06-01

    TNF-alpha plays an important role in the pathogenesis of obesity and insulin resistance in which the effect of TNF-alpha signaling via TNF receptor type 1 (TNFR1) largely remains controversial. To delineate the role of TNFR1-mediated TNF-alpha signaling in the pathogenesis of this disorder, a TNFR1 blocking peptide-Fc fusion protein (TNFR1BP-Fc) was used for the present study. Wistar rats were fed a high-fat/high-sucrose (HFS) diet for 16 wk until obesity and insulin resistance developed. In comparison with increased body weight and fat weight, enlarged adipocytes, and hypertriglyceridemia in the obese state, the subsequent 4-wk treatment with TNFR1BP-Fc resulted in significant weight loss characterized by decreased fat pad weight and adipocyte size and reduced plasma triglycerides. Furthermore, obesity-induced insulin resistance, including hyperinsulinemia, elevated C-peptide, higher degree of hyperglycemia after glucose challenge, and less hypoglycemic response to insulin, was markedly improved, and the compensatory hyperplasia and hypertrophy of pancreatic islets were reduced. Interestingly, treatment with TNFR1BP-Fc markedly suppressed systemic TNF-alpha release and its local expression in pancreatic islets and muscle and adipose tissues. In addition, blockage of TNFR1-mediated TNF-alpha signaling in obese rats significantly enhanced tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1) in the muscle and fat tissues. Our results strongly suggest a pivotal role for TNFR1-mediated TNF-alpha signaling in the pathogenesis of obesity and insulin resistance. Thus, TNFR1BP-Fc may be a good candidate for the treatment of this disease. PMID:18339717

  19. Effects of muscarinic M1 receptor blockade on cocaine-induced elevations of brain dopamine levels and locomotor behavior in rats.

    Science.gov (United States)

    Tanda, Gianluigi; Ebbs, Aaron L; Kopajtic, Theresa A; Elias, Lyn M; Campbell, Bettye L; Newman, Amy H; Katz, Jonathan L

    2007-04-01

    Cholinergic muscarinic systems have been shown to influence dopaminergic function in the central nervous system. In addition, previous studies of benztropine analogs that inhibit dopamine uptake and show antagonism at muscarinic receptors show these drugs to be less effective than cocaine in producing its various prototypic effects such as locomotor stimulation. Because previous pharmacological studies on these topics have used nonselective M1 antagonists, we examined the interactions of preferential M1 muscarinic antagonists and cocaine. Dose-dependent increases in extracellular levels of dopamine in selected brain areas, the nucleus accumbens (NAc) shell and core, and the prefrontal cortex, were produced by cocaine but not by the preferential M1 antagonists telenzepine and trihexyphenidyl. When administered with cocaine, however, both M1 antagonists dose-dependently increased the effects of cocaine on dopamine in the NAc shell, and these effects were selective in that they were not obtained in the NAc core or in the prefrontal cortex. Telenzepine also increased locomotor activity, although the effect was small compared with that of cocaine. The locomotor stimulant effects of trihexyphenidyl, in contrast, approached those of cocaine. Telenzepine attenuated, whereas trihexyphenidyl enhanced the locomotor stimulant effects of cocaine, with neither drug facilitating cocaine-induced stereotypy. The present results indicate that preferential antagonist effects at muscarinic M1 receptors do not uniformly alter all of the effects of cocaine, nor do they explain the differences in effects of cocaine and benztropine analogs, and that the alterations in dopamine levels in the NAc shell do not predict the behavioral effects of the interactions with cocaine. PMID:17255465

  20. Excitatory amino acid receptor blockade within the caudal pressor area and rostral ventrolateral medulla alters cardiovascular responses to nucleus raphe obscurus stimulation in rats

    Directory of Open Access Journals (Sweden)

    Silva N.F.

    2002-01-01

    Full Text Available Pressor responses elicited by stimulation of the nucleus raphe obscurus (NRO depend on the integrity of the rostral ventrolateral medulla (RVLM. Therefore, to test the participation of excitatory amino acid (EAA receptors in the cardiovascular responses evoked by NRO stimulation (1 ms, 100 Hz, 40-70 µA, for 10 s, the EAA antagonist kynurenic acid (Kyn was microinjected at different sites in the ventrolateral medullar surface (2.7 nmol/200 nl of male Wistar rats (270-320 g, N = 39 and NRO stimulation was repeated. The effects of NRO stimulation were: hypertension (deltaMAP = +43 ± 1 mmHg, P<0.01, bradycardia (deltaHR = -30 ± 7 bpm, P<0.01 and apnea. Bilateral microinjection of Kyn into the RVLM, which did not change baseline parameters, almost abolished the bradycardia induced by NRO stimulation (deltaHR = -61 ± 3 before vs -2 ± 3 bpm after Kyn, P<0.01, N = 7. Unilateral microinjection of Kyn into the CVLM did not change baseline parameters or reduce the pressor response to NRO stimulation (deltaMAP = +46 ± 5 before vs +48 ± 5 mmHg after Kyn, N = 6. Kyn bilaterally microinjected into the caudal pressor area reduced blood pressure and heart rate and almost abolished the pressor response to NRO stimulation (deltaMAP = +46 ± 4 mmHg before vs +4 ± 2 mmHg after Kyn, P<0.01, N = 7. These results indicate that EAA receptors on the medullary ventrolateral surface play a role in the modulation of the cardiovascular responses induced by NRO stimulation, and also suggest that the RVLM participates in the modulation of heart rate responses and that the caudal pressor area modulates the pressor response following NRO stimulation.

  1. TLR2 is a primary receptor for Alzheimer's amyloid beta peptide to trigger neuroinflammatory activation.

    NARCIS (Netherlands)

    Liu, S.; Liu, Y.; Hao, W.; Wolf, L.; Kiliaan, A.J.; Penke, B.; Rube, C.E.; Walter, J.; Heneka, M.T.; Hartmann, T.; Menger, M.D.; Fassbender, K.

    2012-01-01

    Microglia activated by extracellularly deposited amyloid beta peptide (Abeta) act as a two-edged sword in Alzheimer's disease pathogenesis: on the one hand, they damage neurons by releasing neurotoxic proinflammatory mediators (M1 activation); on the other hand, they protect neurons by triggering an

  2. Crystal structure of the human beta2 adrenergic G-protein-coupled receptor

    DEFF Research Database (Denmark)

    Rasmussen, Søren Gøgsig Faarup; Choi, Hee-Jung; Rosenbaum, Daniel M;

    2007-01-01

    was crystallized in a lipid environment when bound to an inverse agonist and in complex with a Fab that binds to the third intracellular loop. Diffraction data were obtained by high-brilliance microcrystallography and the structure determined at 3.4 A/3.7 A resolution. The cytoplasmic ends of the beta2AR...

  3. Inducible Conditional Vascular-Specific Overexpression of Peroxisome Proliferator-Activated Receptor Beta/Delta Leads to Rapid Cardiac Hypertrophy

    Science.gov (United States)

    Wagner, Kay-Dietrich; Vukolic, Ana; Baudouy, Delphine; Michiels, Jean-François

    2016-01-01

    Peroxisome proliferator-activated receptors are nuclear receptors which function as ligand-activated transcription factors. Among them, peroxisome proliferator-activated receptor beta/delta (PPARβ/δ) is highly expressed in the heart and thought to have cardioprotective functions due to its beneficial effects in metabolic syndrome. As we already showed that PPARβ/δ activation resulted in an enhanced cardiac angiogenesis and growth without impairment of heart function, we were interested to determine the effects of a specific activation of PPARβ/δ in the vasculature on cardiac performance under normal and in chronic ischemic heart disease conditions. We analyzed the effects of a specific PPARβ/δ overexpression in endothelial cells on the heart using an inducible conditional vascular-specific mouse model. We demonstrate that vessel-specific overexpression of PPARβ/δ induces rapid cardiac angiogenesis and growth with an increase in cardiomyocyte size. Upon myocardial infarction, vascular overexpression of PPARβ/δ, despite the enhanced cardiac vessel formation, does not protect against chronic ischemic injury. Our results suggest that the proper balance of PPARβ/δ activation in the different cardiac cell types is required to obtain beneficial effects on the outcome in chronic ischemic heart disease. PMID:27057154

  4. Specific Endocytosis Blockade of Trypanosoma cruzi Exposed to a Poly-LAcNAc Binding Lectin Suggests that Lectin-Sugar Interactions Participate to Receptor-Mediated Endocytosis

    Science.gov (United States)

    Brosson, Sébastien; Fontaine, Frédéric; Vermeersch, Marjorie; Perez-Morga, David; Pays, Etienne; Bousbata, Sabrina; Salmon, Didier

    2016-01-01

    Trypanosoma cruzi is a protozoan parasite transmitted by a triatomine insect, and causing human Chagas disease in South America. This parasite undergoes a complex life cycle alternating between non-proliferative and dividing forms. Owing to their high energy requirement, replicative epimastigotes of the insect midgut display high endocytic activity. This activity is mainly restricted to the cytostome, by which the cargo is taken up and sorted through the endosomal vesicular network to be delivered to reservosomes, the final lysosomal-like compartments. In African trypanosomes tomato lectin (TL) and ricin, respectively specific to poly-N-acetyllactosamine (poly-LacNAc) and β-D-galactose, allowed the identification of giant chains of poly-LacNAc in N-glycoproteins of the endocytic pathway. We show that in T. cruzi epimastigote forms also, glycoproteins of the endocytic pathway are characterized by the presence of N-linked glycans binding to both ricin and TL. Affinity chromatography using both TL and Griffonia simplicifolia lectin II (GSLII), specific to non-reducing terminal residue of N-acetylglucosamine (GlcNAc), led to an enrichment of glycoproteins of the trypanosomal endocytic pathway. Incubation of live parasites with TL, which selectively bound to the cytostome/cytopharynx, specifically inhibited endocytosis of transferrin (Tf) but not dextran, a marker of fluid endocytosis. Taken together, our data suggest that N-glycan modification of endocytic components plays a crucial role in receptor-mediated endocytosis of T. cruzi. PMID:27685262

  5. Discovery of Innovative Therapies for Rare Immune-Mediated Inflammatory Diseases via Off-Label Prescription of Biologics: The Case of IL-6 Receptor Blockade in Castleman's Disease.

    Science.gov (United States)

    Musters, Anne; Assaf, Amira; Gerlag, Danielle M; Tak, Paul P; Tas, Sander W

    2015-01-01

    Biologics have revolutionized the field of clinical immunology and proven to be both effective and safe in common immune-mediated inflammatory diseases (IMIDs) such as rheumatoid arthritis, inflammatory bowel diseases, and various hematological disorders. However, in patients with rare, severe IMIDs failing on standard therapies, it is virtually impossible to conduct randomized controlled trials. Therefore, biologics are usually prescribed off-label in these often severely ill patients. Unfortunately, off-label prescription is sometimes hampered in these diseases due to a lack of reimbursement that is often based on a presumed lack of evidence for effectiveness. In the present article, we will discuss that off-label prescription of biologics can be a good way to discover new treatments for rare diseases. This will be illustrated using a case of multicentric Castleman's disease, an immune-mediated lymphoproliferative disorder, in which off-label tocilizumab (humanized anti-IL-6 receptor blocking antibody) treatment resulted in remarkable clinical improvement. Furthermore, we will give recommendations for monitoring efficacy and safety of biologic treatment in rare IMIDs, including the use of registries. In conclusion, we put forward that innovative treatments for rare IMIDs can be discovered via off-label prescription of biologicals, provided that this is based on rational arguments including knowledge of the pathophysiology of the disease.

  6. Phenserine, a novel acetylcholinesterase inhibitor, attenuates impaired learning of rats in a 14-unit T-maze induced by blockade of the N-methyl-D-aspartate receptor.

    Science.gov (United States)

    Patel, N; Spangler, E L; Greig, N H; Yu, Q S; Ingram, D K; Meyer, R C

    1998-01-01

    The present study evaluated the interaction of the glutamatergic and acetylcholinergic systems in memory formation, with an overall emphasis on developing multi-system approaches for treating age-related cognitive decline and Alzheimer' s disease. Specifically, we used a 14-unit T-maze to investigate whether phenserine (PHEN), a long-acting acetylcholinesterase inhibitor, could overcome a learning deficit in rats induced by the NMDA receptor antagonist, 3-(+/-) 2-carboxypiperzin-4-yl) propyl phosphonic acid (CPP). Prior to drug treatment, 3-month-old male Fischer-344 rats were trained to criterion (13 of 15 shock avoidances) in a straight runway. Twenty-four hours later, rats were given i.p. injections of saline (SAL), CPP (9 mg/kg) + SAL or CPP + PHEN (0.25, 0.5 or 0.75 mg/kg) and received 15 massed training trials in a 14-unit T-maze. CPP significantly increased the number of errors made in the maze relative to controls, and phenserine significantly reduced the number of errors made relative to rats receiving CPP only, with the lowest dose being the most effective. These results provide further support of phenserine's potent, cognitive-enhancing properties, and suggest that combined modulation of glutamatergic and acetylcholinergic systems may be of potential benefit in developing new pharmacotherapies for Alzheimer's disease and age-related cognitive decline. PMID:9592071

  7. Swimming exercise changes hemodynamic responses evoked by blockade of excitatory amino receptors in the rostral ventrolateral medulla in spontaneously hypertensive rats.

    Science.gov (United States)

    Ogihara, Cristiana A; Schoorlemmer, Gerhardus H M; Lazari, Maria de Fátima M; Giannocco, Gisele; Lopes, Oswaldo U; Colombari, Eduardo; Sato, Monica A

    2014-01-01

    Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercise would change the neurotransmission in the rostral ventrolateral medulla (RVLM), a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Bilateral injections of kynurenic acid (KYN) were carried out in the RVLM in sedentary- (S-) or exercised- (E-) SHR and WKY rats submitted to swimming for 6 weeks. Rats were α-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor). Injections of KYN into the RVLM elicited a major vasodilation in the hindlimb more than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hindlimb vasodilation evoked by KYN and increased the mesenteric vasodilation in E-SHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR. PMID:24696852

  8. Swimming Exercise Changes Hemodynamic Responses Evoked by Blockade of Excitatory Amino Receptors in the Rostral Ventrolateral Medulla in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Cristiana A. Ogihara

    2014-01-01

    Full Text Available Exercise training reduces sympathetic activity in hypertensive humans and rats. We hypothesized that the swimming exercise would change the neurotransmission in the rostral ventrolateral medulla (RVLM, a key region involved in sympathetic outflow, and hemodynamic control in spontaneously hypertensive rats (SHR and Wistar-Kyoto (WKY rats. Bilateral injections of kynurenic acid (KYN were carried out in the RVLM in sedentary- (S- or exercised- (E- SHR and WKY rats submitted to swimming for 6  weeks. Rats were α-chloralose anesthetized and artificially ventilated, with Doppler flow probes around the lower abdominal aorta and superior mesenteric artery. Injections into the RVLM were made before and after i.v. L-NAME (nitric oxide synthase, NOS, inhibitor. Injections of KYN into the RVLM elicited a major vasodilation in the hindlimb more than in the mesenteric artery in E-SHR compared to S-SHR, but similar decrease in arterial pressure was observed in both groups. Injections of KYN into the RVLM after i.v. L-NAME attenuated the hindlimb vasodilation evoked by KYN and increased the mesenteric vasodilation in E-SHR. Swimming exercise can enhance the hindlimb vasodilation mediated by peripheral NO release, reducing the activation of neurons with EAA receptors in the RVLM in SHR.

  9. Evaluation of spirometry values in relation to beta-2-adrenergic receptor gene polymorphism

    OpenAIRE

    Poziomkowska-Gesicka, I; Dzieciolowska-Baran, E; Gawlikowska-Sroka, A; Slowik-Zylka, D; Sroczynski, T

    2010-01-01

    Introduction The vagus nerve plays a special role in the control of respiratory system activity which represents the parasympathetic part of the autonomic nervous system. A small bronchial innervation by the sympathetic system also is observed, and there is a significant expression of adrenergic receptors, in particular β2 receptors, in the airways. The development of genetics and molecular biology allows for a detailed study which can clarify the essential elements in the pathogenesis of man...

  10. Immunolocalization of estrogen receptor beta in the epididymis of mature and immature pigs.

    OpenAIRE

    Maggiolini, M.; L Siciliano; B Bilinska; CARPINO, A.; V Rago

    2004-01-01

    A growing body of evidence suggests a role of estrogens in the male reproduction via their specific estrogen receptors (ERalpha/ERbeta). Estrogen receptor distribution along the genital tract tissues has been described in different species, but it is unknown in the pig. Therefore, the aim of the present study was to localize ERbeta in the epididymis of mature and immature pigs (aged 2 and 18 months, respectively). Immunohistochemistry was carried out on paraffin-embedded tissues using a mouse...

  11. Association of estrogen receptor beta variants and serum levels of estradiol with risk of colorectal cancer: a case control study

    Directory of Open Access Journals (Sweden)

    Wu Huanlei

    2012-07-01

    Full Text Available Abstract Background Endogenous estrogens may play a vital role in colorectal tumorigenesis. Estrogen receptor beta is the predominant subtype which mediates the biological effect of estrogens, while loss of expression of estrogen receptor beta has been indicated as a common step in the development of colorectal cancer (CRC. Epidemiological studies have revealed several functional polymorphisms of estrogen receptor beta (ESR2 for cancer risk, but relevant study in CRC is limited, particularly in men. This study aimed to investigate the association of circulating estradiol and variations of ESR2 with CRC risk in men. Methods We initiated a case–control study consisting of 390 patients with CRC and 445 healthy controls in men only. We genotyped ESR2 single nucleotide polymorphisms (SNPs rs1256049 and rs4986938 and measured serum estradiol concentration using chemilluminescence immunoassay. Multivariable logistic regression model was performed to evaluate the associations between these variables and CRC risk. Results ESR2 rs1256049 CT/TT genotypes were associated with reduced risk of CRC (odds ratio [OR], 0.7, 95% confidence interval [CI], 0.5–1.0, while rs4986938 CT/TT genotypes were associated with increased risk of CRC (OR, 1.5, 95% CI, 1.0–2.1. In addition, the CRC risk increased with the number of risk genotypes of these two SNPs in a dose–response manner (Ptrend, 0.003. Specifically, subjects carrying risk genotypes of both SNPs had the highest risk of CRC (OR, 2.0, 95% CI, 1.3–3.3.. Moreover, serum estradiol concentration alone was associated with risk of CRC in men (OR, 1.2, 95% CI, 1.0–1.3. However, individuals presenting both rs4986938 CT/TT genotypes and high level of serum estradiol had a high risk of CRC (OR, 2.3, 95% CI, 1.4–3.9, compared with those presenting CC genotype and low level of serum estradiol. The similar joint results were not observed for SNP rs1256049. Conclusions These results suggest that endogenous

  12. High value of the radiobiological parameter Dq correlates to expression of the transforming growth factor beta type II receptor in a panel of small cell lung cancer cell lines

    DEFF Research Database (Denmark)

    Hougaard, S; Krarup, M; Nørgaard, P;

    1998-01-01

    Our panel of SCLC cell lines have previously been examined for their radiobiological characteristics and sensitivity to treatment with TGF beta 1. In this study we examined the possible correlations between radiobiological parameters and the expression of the TGF beta type II receptor (TGF beta-r...... role for the repair of radiation induced DNA damage in SCLC....

  13. Stoichiometry of expressed alpha(4)beta(2)delta gamma-aminobutyric acid type A receptors depends on the ratio of subunit cDNA transfected.

    Science.gov (United States)

    Wagoner, Kelly R; Czajkowski, Cynthia

    2010-05-01

    The gamma-aminobutyric acid type A receptor (GABA(A)R) is the target of many depressants, including benzodiazepines, anesthetics, and alcohol. Although the highly prevalent alphabetagamma GABA(A)R subtype mediates the majority of fast synaptic inhibition in the brain, receptors containing delta subunits also play a key role, mediating tonic inhibition and the actions of endogenous neurosteroids and alcohol. However, the fundamental properties of delta-containing GABA(A)Rs, such as subunit stoichiometry, are not well established. To determine subunit stoichiometry of expressed delta-containing GABA(A)Rs, we inserted the alpha-bungarotoxin binding site tag in the alpha(4), beta(2), and delta subunit N termini. An enhanced green fluorescent protein tag was also inserted into the beta(2) subunit to shift its molecular weight, allowing us to separate subunits using SDS-PAGE. Tagged alpha(4)beta(2)delta GABA(A)Rs were expressed in HEK293T cells using various ratios of subunit cDNA, and receptor subunit stoichiometry was determined by quantitating fluorescent alpha-bungarotoxin bound to each subunit on Western blots of surface immunopurified tagged GABA(A)Rs. The results demonstrate that the subunit stoichiometry of alpha(4)beta(2)delta GABA(A)Rs is regulated by the ratio of subunit cDNAs transfected. Increasing the ratio of delta subunit cDNA transfected increased delta subunit incorporation into surface receptors with a concomitant decrease in beta(2) subunit incorporation. Because receptor subunit stoichiometry can directly influence GABA(A)R pharmacological and functional properties, considering how the transfection protocols used affect subunit stoichiometry is essential when studying heterologously expressed alpha(4)beta(2)delta GABA(A)Rs. Successful bungarotoxin binding site tagging of GABA(A)R subunits is a novel tool with which to accurately quantitate subunit stoichiometry and will be useful for monitoring GABA(A)R trafficking in live cells.

  14. The role of 14-3-3{beta} in transcriptional activation of estrogen receptor {alpha} and its involvement in proliferation of breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yoonseo; Kim, Hyungjin; Jang, Sung-Wuk [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of); Ko, Jesang, E-mail: jesangko@korea.ac.kr [School of Life Sciences and Biotechnology, Korea University, Seoul 136-701 (Korea, Republic of)

    2011-10-14

    Highlights: {yields} 14-3-3{beta} interacts with ER{alpha} and the interaction is Akt-dependent. {yields} 14-3-3{beta} regulates the transcriptional activity of ER{alpha} in a ligand-dependent manner. {yields} 14-3-3{beta} increases expressions of ER{alpha} target genes. {yields} 14-3-3{beta} increases breast cancer cell proliferation. -- Abstract: The estrogen receptor (ER) functions as a transcription factor that mediates the effects of estrogen. ER{alpha}, which plays a crucial role in the development and progression of breast cancer, is activated by estrogen binding, leading to receptor phosphorylation, dimerization, and recruitment of co-activators and chaperons to the estrogen-bound receptor complex. The 14-3-3 proteins bind to target proteins via phosphorylation and influence many cellular events by altering their subcellular localization or acting as a chaperone. However, regulation of ER{alpha} expression and transactivation by the 14-3-3 proteins has not been reported. We demonstrate that 14-3-3{beta} functions as a positive regulator of ER{alpha} through a direct protein-protein interaction in an estrogen-dependent manner. Ectopic expression of 14-3-3{beta} stimulated ER{alpha}-mediated transcriptional activity in MCF-7 breast cancer cells. Enhanced ER{alpha} transcriptional activity due to 14-3-3{beta} increased the expressions of the endogenous ER{alpha} target genes, leading to proliferation of breast cancer cells. We suggest that 14-3-3{beta} has oncogenic potential in breast cancer via binding to ER{alpha} and activation of the transcriptional activity of ER{alpha}.

  15. Molecular characterization of thyroid hormone receptor beta from Schistosoma japonicum and assessment of its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice

    OpenAIRE

    Qiu Chunhui; Liu Shengfa; Hong Yang; Fu Zhiqiang; Wei Meimei; Ai Dezhou; Lin Jiaojiao

    2012-01-01

    Abstract Background Thyroid hormones (TH) modulate growth, development and differentiation and metabolic processes by interacting with thyroid hormone receptors (THRs). The purpose of this study was to identify a novel thyroid hormone receptor beta encoding gene of Schistosoma japonicum (SjTHRβ) and to investigate its potential as a vaccine candidate antigen against schistosomiasis in BALB/c mice. Methods The full-length cDNA sequence of SjTHRβ, its gene organization, and its transcript level...

  16. Analysis of beta, gamma, and delta T-cell receptor genes in mycosis fungoides and Sezary syndrome.

    Science.gov (United States)

    Whittaker, S J; Smith, N P; Jones, R R; Luzzatto, L

    1991-10-01

    The authors have analyzed the configuration of immunoglobulin (Ig) and beta, gamma and delta T-cell receptor (TCR) genes in DNA extracted from skin, lymph nodes, and peripheral blood mononuclear cells obtained from 41 patients with mycosis fungoides (MF), 14 patients with Sezary syndrome, and 13 patients with benign inflammatory dermatoses. No discrete rearranged bands (DRB) were detected in patients with inflammatory dermatoses. In tissue DNA from 19 patients with MF DRB were detected with beta and gamma, but not delta TCR probes. Only one patient with MF had a rearrangement of gamma and delta with germ line beta TCR genes. In 13 patients multiple biopsies were analyzed and DRB, when present, were identical in different lesions from individual patients. In three patients analysis of DNA from dermatopathic lymph nodes did not reveal DRB. Analysis of peripheral blood DNA from 24 patients revealed a discrete rearrangement of the gamma TCR gene in four patients and both beta and gamma genes in four additional patients. In MF DRB were detected more frequently with advancing stage of disease in tissues (P less than 0.01) but not in peripheral blood (P equals 0.36). Of 14 patients with Sezary syndrome, eight had DRB in peripheral blood DNA with both beta and gamma probes and in three of these patients identical DRB were also detected in DNA from skin biopsy samples. In contrast, DRB were not detected in the peripheral blood of the other six patients. In both MF and Sezary syndrome there was no restricted usage of particular V gamma genes. These results indicate that in MF (1) T-cell clones can be detected in skin biopsy specimens from the majority of patients with early stage disease, (2) gamma delta T-cell clones are only rarely found, and (3) TCR gene analysis can detect T-cell clones in the peripheral blood with a greater degree of specificity than conventional light microscopic study. In Sezary syndrome these studies also suggest that a subset of patients have a

  17. Axial (HNF3beta) and retinoic acid receptors are regulators of the zebrafish sonic hedgehog promoter.

    OpenAIRE

    Chang, B E; Blader, P.; Fischer, N.; Ingham, P W; Strähle, U.

    1997-01-01

    The signalling molecule Sonic hedgehog is involved in a multitude of distinct patterning processes during vertebrate embryogenesis. In the nascent body axis of the zebrafish embryo, sonic hedgehog is co-expressed with axial (HNF3beta in mammals), a transcription regulator of the winged helix family. We show here that misexpression of axial leads to ectopic activation of sonic hedgehog expression in the zebrafish, suggesting that axial is a regulator of sonic hedgehog transcription. The sonic ...

  18. [Central effects of five beta-adrenergic receptor blockers in healthy volunteers: a quantitative EEG study].

    Science.gov (United States)

    Sabot, C; Pechadre, J C; Beudin, P; Lauxerois, M; Trolese, J F; Kantelip, J P; Ducher, J L; Gibert, J

    1989-03-01

    The effects of five beta blockers on the central nervous system of healthy subjects was studied by computerized EEG analysis. All subjects underwent continuous recording with a Holter magnetic type recorder during the experimental period. For 10 consecutive days, five groups of subjects received alternately placebo and the beta blockers acebutolol 600 mg, carteolol 20 mg, metoprolol 200 mg, pindolol 30 mg and sotalol 320 mg. EEG recordings (C4/P4, P4/02 and C3/P3, P3/01) lasting 5 min were made between 8.30 and 9.30 a.m. Subjects were at rest with eyes closed and there was no vigilance control. The signal was recorded on a magnetic tape recorder and then processed by Nicolet MED 80 system. Comparisons of absolute and relative powers and of average frequencies were then made between the different sequences and groups. The possible correlations between the changes observed in the power spectrum and the clinical, pharmacological and pharmacokinetic specific properties of each beta blocker are discussed.

  19. A Specific Cholesterol Binding Site Is Established by the 2.8 Å Structure of the Human [beta][subscript 2]-Adrenergic Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Michael A.; Cherezov, Vadim; Griffith, Mark T.; Roth, Christopher B.; Jaakola, Veli-Pekka; Chien, Ellen Y.T.; Velasquez, Jeffrey; Kuhn, Peter; Stevens, Raymond C. (Scripps)

    2008-07-08

    The role of cholesterol in eukaryotic membrane protein function has been attributed primarily to an influence on membrane fluidity and curvature. We present the 2.8 {angstrom} resolution crystal structure of a thermally stabilized human {beta}{sub 2}-adrenergic receptor bound to cholesterol and the partial inverse agonist timolol. The receptors pack as monomers in an antiparallel association with two distinct cholesterol molecules bound per receptor, but not in the packing interface, thereby indicating a structurally relevant cholesterol-binding site between helices I, II, III, and IV. Thermal stability analysis using isothermal denaturation confirms that a cholesterol analog significantly enhances the stability of the receptor. A consensus motif is defined that predicts cholesterol binding for 44% of human class A receptors, suggesting that specific sterol binding is important to the structure and stability of other G protein-coupled receptors, and that this site may provide a target for therapeutic discovery.

  20. Neu1 desialylation of sialyl alpha-2,3-linked beta-galactosyl residues of TOLL-like receptor 4 is essential for receptor activation and cellular signaling.

    Science.gov (United States)

    Amith, Schammim Ray; Jayanth, Preethi; Franchuk, Susan; Finlay, Trisha; Seyrantepe, Volkan; Beyaert, Rudi; Pshezhetsky, Alexey V; Szewczuk, Myron R

    2010-02-01

    The ectodomain of TOLL-like receptors (TLR) is highly glycosylated with several N-linked gylcosylation sites located in the inner concave surface. The precise role of these sugar N-glycans in TLR receptor activation is unknown. Recently, we have shown that Neu1 sialidase and not Neu2, -3 and -4 forms a complex with TLR-2, -3 and -4 receptors on the cell-surface membrane of naïve and activated macrophage cells (Glycoconj J DOI 10.1007/s10719-009-9239-8). Activation of Neu1 is induced by TLR ligands binding to their respective receptors. Here, we show that endotoxin lipopolysaccharide (LPS)-induced MyD88/TLR4 complex formation and subsequent NFkappaB activation is dependent on the removal of alpha-2,3-sialyl residue linked to beta-galactoside of TLR4 by the Neu1 activity associated with LPS-stimulated live primary macrophage cells, macrophage and dendritic cell lines but not with primary Neu1-deficient macrophage cells. Exogenous alpha-2,3 sialyl specific neuraminidase (Streptoccocus pneumoniae) and wild-type T. cruzi trans-sialidase (TS) but not the catalytically inactive mutant TSAsp98-Glu mediate TLR4 dimerization to facilitate MyD88/TLR4 complex formation and NFkappaB activation similar to those responses seen with LPS. These same TLR ligand-induced NFkappaB responses are not observed in TLR deficient HEK293 cells, but are re-established in HEK293 cells stably transfected with TLR4/MD2, and are significantly inhibited by alpha-2,3-sialyl specific Maackia amurensis (MAL-2) lectin, alpha-2,3-sialyl specific galectin-1 and neuraminidase inhibitor Tamiflu but not by alpha-2,6-sialyl specific Sambucus nigra lectin (SNA). Taken together, the findings suggest that Neu1 desialylation of alpha-2,3-sialyl residues of TLR receptors enables in removing a steric hinderance to receptor association for TLR activation and cellular signaling. PMID:19796680

  1. Preliminary study on association of beta2-adrenergic receptor polymorphism with hypertension in hypertensive subjects attending Balok Health Centre, Kuantan.

    Science.gov (United States)

    Atia, A E; Norsidah, K; Nor Zamzila, A; Rafidah Hanim, M; Samsul, D; Aznan, M A M; Rashidah, A R; Norlelawati, A T

    2012-02-01

    Polymorphisms within the beta2-adrenergic receptor (ADRB2) gene have been repeatedly linked to hypertension. Among the ADRB2 polymorphisms detected, Arg16Gly and Gln27Glu codons are considered the two most important variations. The amino acid substitution at these codons may lead to abnormal regulation of ADRB2 activity. The aim of the present study was to assess the association between ADRB2 polymorphisms and hypertension. This case-control study consisted of 100 unrelated subjects (50 hypertensive and 50 matched normal controls). Arg16Gly and the Gln27Glu polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay. There were no significant evidence of association in allelic and genotypes distribution of Arg16Gly and Glu27Gln with blood pressure and hypertension. These findings suggest that the variation within codon 16 and 27 of ADRB2 gene were unlikely to confer genetic susceptibility for hypertension in our population samples. PMID:22582545

  2. Human epidermal growth factor receptor 3 (HER3) blockade with U3-1287/AMG888 enhances the efficacy of radiation therapy in lung and head and neck carcinoma.

    Science.gov (United States)

    Li, Chunrong; Brand, Toni M; Iida, Mari; Huang, Shyhmin; Armstrong, Eric A; van der Kogel, Albert; Wheeler, Deric L

    2013-09-01

    HER3 is a member of the epidermal growth factor receptor (EGFR) family of receptor tyrosine kinases. In the present study, we investigated the capacity of the HER3 blocking antibody, U3-1287/AMG888, to modulate the in vitro and in vivo radiation response of human squamous cell carcinomas of the lung and head and neck. We screened a battery of cell lines from these tumors for HER3 expression and demonstrated that all cell lines screened exhibited expression of HER3. Importantly, U3-1287/AMG888 treatment could block both basal HER3 activity and radiation induced HER3 activation. Proliferation assays indicated that HER3 blockade could decrease the proliferation of both HNSCC cell line SCC6 and NSCLC cell line H226. Further, we demonstrated that U3-1287/AMG888 can sensitize cells to radiation in clonogenic survival assays, in addition to increasing DNA damage as detected via λ-H2AX immunofluorescence. To determine if U3-1287/AMG888 could enhance radiation sensitivity in vivo we performed tumor growth delay experiments using SCC6, SCC1483, and H226 xenografts. The results of these experiments indicated that the combination of U3-1287/AMG888 and radiation could decrease tumor growth in studies using single or fractionated doses of radiation. Analysis of HER3 expression in tumor samples indicated that radiation treatment activated HER3 in vivo and that U3-1287/AMG888 could abrogate this activation. Immunohistochemistry analysis of SCC6 tumors treated with both U3-1287/AMG888 and a single dose of radiation demonstrated that various cell survival and proliferation markers could be reduced. Collectively our findings suggest that U3-1287/AMG888 in combination with radiation has an impact on cell and tumor growth by increasing DNA damage and cell death. These findings suggest that HER3 may play an important role in response to radiation therapy and blocking its activity in combination with radiation may be of therapeutic benefit in human tumors. PMID:23998444

  3. Polymorphism at the ovine beta3-adrenergic receptor locus: associations with birth weight, growth rate, carcass composition and cold survival.

    Science.gov (United States)

    Forrest, R H; Hickford, J G H; Hogan, A; Frampton, C

    2003-02-01

    The beta3-adrenergic receptors (ADRB3s) are predominantly found on the surface of adipocytes and are the major mediators of the lipolytic and thermogenic effects of high catecholamine concentrations. Polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis of part of the ovine beta3-adrenergic receptor gene (ADRB3) intron was used to screen 12 large Merino half-sib families for sequence variation. Six different alleles that segregated in a Mendelian fashion were observed. The genetic basis for the allelic differences were identified by sequencing the ADRB3 (coding and non-coding regions) from animals that were homozygous for each of the alleles. Five sire lines (two Merino x Merino, two Merino x Coopworth, one Dorset Down x Coopworth) provided phenotypic and genotypic data used to ascertain the effects of allelic variation at the ADRB3 locus on birth weight, weaning weight, growth rate (up until weaning), carcass composition at 63 days post-weaning and cold survival. Statistical analyses within each half-sib family showed that in some sire lines (S13, S15, and S17) the inheritance of a particular allele was associated with increased birth weights and/or increased growth rates up until weaning. The inheritance of a particular sire allele was associated with fatter carcasses in sire line S16. Chi-squared analysis revealed the association of the E allele with cold survival and the D allele with cold-related mortality in sire line S14. Such associations support the hypothesis that ADRB3s are involved in energy homeostasis. With more research, the variation detected at the ADRB3 locus may assist in the genetic selection for desirable animal production traits.

  4. Ultrastructural characterization of noradrenergic- and beta-adrenergic receptor-containing profiles in the lateral nucleus of the amygdala

    Directory of Open Access Journals (Sweden)

    Claudia Farb

    2010-10-01

    Full Text Available Norepinephrine (NE is thought to play a key role in fear and anxiety, but its role in amygdala-dependent Pavlovian fear conditioning, a major model for understanding the neural basis of fear, is poorly understood. The lateral nucleus of the amygdala (LA is a critical brain region for fear learning and regulating the effects of stress on memory. To understand better the cellular mechanisms of NE and its adrenergic receptors in the LA, we used antibodies directed against dopamine beta-hydroxylase (DβH, the synthetic enzyme for NE, or against two different isoforms of the beta-adrenergic receptors (βARs, one that predominately recognizes neurons (βAR 248 and the other astrocytes (βAR 404, to characterize the microenvironments of DβH and βAR. By electron microscopy, most DβH terminals did not make synapses, but when they did, they formed both asymmetric and symmetric synapses. By light microscopy, βARs were present in both neurons and astrocytes. Confocal microscopy revealed that both excitatory and inhibitory neurons express βAR248. By electron microscopy, βAR 248 was present in neuronal cell bodies, dendritic shafts and spines, and some axon terminals and astrocytes. When in dendrites and spines, βAR 248 was frequently concentrated along plasma membranes and at post-synaptic densities of asymmetric (excitatory synapses. βAR 404 was expressed predominately in astrocytic cell bodies and processes. These astrocytic processes were frequently interposed between unlabeled terminals or ensheathed asymmetric synapses. Our findings provide a morphological basis for understanding ways in which NE may modulate transmission by acting via synaptic or non-synaptic mechanisms in the LA.

  5. Conversion of agonist site to metal-ion chelator site in the beta(2)-adrenergic receptor

    DEFF Research Database (Denmark)

    Elling, C E; Thirstrup, K; Holst, Birgitte;

    1999-01-01

    in the mutant receptors not by normal catecholamine ligands but instead either by free zinc ions or by zinc or copper ions in complex with small hydrophobic metal-ion chelators. Chelation of the metal ions by small hydrophobic chelators such as phenanthroline or bipyridine protected the cells from the toxic...... effect of, for example Cu(2+), and in several cases increased the affinity of the ions for the agonistic site. Wash-out experiments and structure-activity analysis indicated, that the high-affinity chelators and the metal ions bind and activate the mutant receptor as metal ion guided ligand complexes....... Because of the well-understood binding geometry of the small metal ions, an important distance constraint has here been imposed between TM-III and -VII in the active, signaling conformation of 7TM receptors. It is suggested that atoxic metal-ion chelator complexes could possibly in the future be used...

  6. Cloning of T-cell antigen receptor beta chain cDNAs from Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Hordvik, I; Jacob, A L; Charlemagne, J; Endresen, C

    1996-01-01

    Atlantic salmon (Salmo salar) cDNAs encoding the T-cell antigen receptor beta chain (TCRB) were isolated from leukocyte RNA by reverse transcription - polymerase chain reaction (RT-PCR). Twenty-five distinct cDNA fragments covering the variable (V) - diversity (D) - joining (J) junction and part of the constant (C) region were characterized; the sequences of which indicate interchangeable V/D/J usage and expression in the context of one TCRBC gene. Full-length TCRBC sequence information was derived from a leukocyte cDNA library. Key residues of the salmon TCRBC region are in good agreement with those of other species. One distinct exception is the absence of the hinge region cysteine residue which is involved in covalent bonding between the alpha and beta chain in mammalian TCRs. As in amphibian and avian species, the salmon TCRBC membrane proximal region is considerably shorter than the mammalian. An octamer sequence (GGACAGGG) very similar to amphibian, avian, and mammalian D sequences could be recognized in the VDJ junctions from salmon. The pattern of VDJ variability also indicates that mechanisms like trimming and addition occur in fish as in higher vertebrates. Compared with mammals, a relatively high frequency (32%) of the VDJ junctions in salmon were out of frame. PMID:8881032

  7. AT1-IR-beta Association: A New Mechanism for the Inhibition of Insulin Receptor Function in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Lakshmi Pulakat

    2008-01-01

    Full Text Available Epidemiological evidence show that increased mortality in breast cancer is linked to hypertension and insulin resistance. Because Angiotensin II (Ang II, a hormone implicated in hypertension and insulin resistance, is a normal mitogen for breast tissue and elevated expression of the Ang II receptor AT1 is seen in breast cancer, we analyzed the effects of Ang II exposure on the functions of IR in human breast cancer cell line MCF-7. Exposure of MCF-7 to Ang II for 2 hours a significantly reduced 125I-insulin binding to IR, and b induced co-immuno-precipitation of the AT1 with IR-beta subunit. These Ang II-mediated effects on IR were inhibited by the AT1 antagonist losartan, and were not observed when exposure time was below 1-hour. These observations suggest extended exposure to Ang II have detrimental effects on insulin binding to IR that were not discovered in the previous studies where Ang II-exposure of insulin responsive cells was performed for periods less than one hour. In addition, they suggest a novel mechanism that involves AT1-IR-beta association for the inhibition of insulin binding to IR in response to extended exposure (2-hours of breast cancer cells to elevated levels of Ang II (as seen in hypertensive patients, and provides a molecular link for the inhibition of normal IR signaling by Ang II in breast cancer.

  8. Folate receptor beta as a potential delivery route for novel folate antagonists to macrophages in the synovial tissue of rheumatoid arthritis patients

    NARCIS (Netherlands)

    J.W. van der Heijden; R. Oerlemans; B.A.C. Dijkmans; H. Qi; C.J. van der Laken; W.F. Lems; A.L. Jackman; M.C. Kraan; P.P. Tak; M. Ratnam; G. Jansen

    2009-01-01

    OBJECTIVE: To determine the expression of folate receptor beta (FRbeta) in synovial biopsy tissues and peripheral blood lymphocytes from rheumatoid arthritis (RA) patients and to identify novel folate antagonists that are more selective in the targeting and internalization of FRbeta than methotrexat

  9. Lack of associations between serum leptin, a polymorphism in the gene for the beta(3)-adrenergic receptor and glucose tolerance in the Dutch population.

    NARCIS (Netherlands)

    Janssen, JAMJL; Koper, JW; Stolk, RP; Englaro, P; Uitterlinden, AG; Huang, Q; van Leeuwen, JPTM; Blum, WF; Attanasio, AMF; Pols, HAP; Grobbee, DE; de Jong, FH; Lamberts, SWJ

    1998-01-01

    BACKGROUND The associations between leptin levels and the prevalence of a polymorphism in the beta(3)-adrenergic receptor were studied in a cross-sectional analysis of 600 participants in a population-based study, which were stratified for glucose tolerance by an oral glucose tolerance test. METHODS

  10. The nicotinic alpha7 acetylcholine receptor agonist ssr180711 is unable to activate limbic neurons in mice overexpressing human amyloid-beta1-42

    DEFF Research Database (Denmark)

    Soderman, A.; Spang-Thomsen, Mogens; Hansen, H.;

    2008-01-01

    Recent studies have demonstrated that amyloid-beta1-42 (Abeta1-42) binds to the nicotinergic alpha7 acetylcholine receptor (alpha7 nAChR) and that the application of Abeta1-42 to cells inhibits the function of the alpha7 nAChR. The in vivo consequences of the pharmacological activation of the alpha...

  11. Studies of associations between the Arg389Gly polymorphism of the beta1-adrenergic receptor gene (ADRB1) and hypertension and obesity in 7677 Danish white subjects

    DEFF Research Database (Denmark)

    Gjesing, A P; Andersen, G; Albrechtsen, A;

    2007-01-01

    Activation of the beta(1)-adrenergic receptor (ADRB1) causes increased lipolysis in adipose tissue and enhances cardiac output. Analysis of the association of the functional ADRB1 Arg389Gly variant with obesity and hypertension has given ambiguous results. To clarify the potential impact...

  12. TRANSCRIPTIONAL REGULATION OF RETINOIC ACID RECEPTOR-BETA IN RETINOIC ACID-SENSITIVE AND ACID-RESISTANT P19-EMBRYOCARCINOMA CELLS

    NARCIS (Netherlands)

    KRUYT, FAE; VANDENBRINK, CE; DEFIZE, LHK; DONATH, MJ; KASTNER, P; KRUIJER, W; CHAMBON, P; VANDERSAAG, PT; Kruyt, Frank

    1991-01-01

    As in other embryocarcinoma (EC) cell lines retinoic acid (RA) rapidly induces expression of the nuclear retinoic acid receptor (RAR) beta in murine P19 EC cells, while RAR-alpha is expressed constitutively. In the RA-resistant P19 EC-derived RAC65 cells, however, there is no such induction and an a

  13. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, de J.; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (ß2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  14. Beta-adrenergic receptor agonists induce the release of granulocyte chemotactic protein-2, oncostatin M, and vascular endothelial growth factor from macrophages

    NARCIS (Netherlands)

    Verhoeckx, K.C.M.; Doornbos, R.P.; Witkamp, R.F.; Greef, J. van der; Rodenburg, R.J.T.

    2006-01-01

    Vascular endothelial growth factor (VEGF), oncostatin M (OSM), and granulocyte chemotactic protein-2 (GCP-2/CXCL6) are up-regulated in U937 macrophages and peripheral blood macrophages exposed to LPS, beta-adrenergic receptor (β2-AR) agonists (e.g. zilpaterol, and clenbuterol) and some other agents

  15. TGF-beta receptor 2 downregulation in tumour-associated stroma worsens prognosis and high-grade tumours show more tumour-associated macrophages and lower TGF-beta1 expression in colon carcinoma: a retrospective study

    Directory of Open Access Journals (Sweden)

    Papadopoulos Thomas

    2007-08-01

    Full Text Available Abstract Background Histological phenotype and clinical behaviour of malignant tumours are not only dependent on alterations in the epithelial cell compartment, but are affected by their interaction with inflammatory cells and tumour-associated stroma. Studies in animal models have shown influence of tumour-associated macrophages (TAM on histological grade of differentiation in colon carcinoma. Disruption of transforming growth factor beta (TGF-beta signalling in tumour cells is related to more aggressive clinical behaviour. Expression data of components of this pathway in tumour-associated stroma is limited. Methods Tissue micro arrays of 310 colon carcinomas from curatively resected patients in UICC stage II and III were established. In a first step we quantified amount of CD68 positive TAMs and expression of components of TGF-beta signalling (TGF-beta1, TGF-beta receptors type 1 and 2, Smad 3 and 4 in tumour and associated stroma. Further we analyzed correlation to histological and clinical parameters (histological grade of differentiation (low-grade (i.e. grade 1 and 2 vs. high-grade (i.e. grade 3 and 4, lymph node metastasis, distant metastasis, 5 year cancer related survival using Chi-square or Fisher's exact test, when appropriate, to compare frequencies, Kaplan-Meier method to calculate 5-year rates of distant metastases and cancer-related survival and log rank test to compare the rates of distant metastases and survival. To identify independent prognostic factors Cox regression analysis including lymph node status and grading was performed. Results High-grade tumours and those with lymph node metastases showed higher rates of TAMs and lower expression of TGF-beta1. Loss of nuclear Smad4 expression in tumor was associated with presence of lymph node metastasis, but no influence on prognosis could be demonstrated. Decrease of both TGF-beta receptors in tumour-associated stroma was associated with increased lymph node metastasis and

  16. Influence of pudendal nerve blockade on stress relaxation in the female urethra

    DEFF Research Database (Denmark)

    Thind, P; Bagi, P; Mieszczak, C;

    1996-01-01

    The urethral pressure decay following a sudden and sustained dilatation corresponds to stress relaxation. Urethral stress relaxation can be described by the equation Pt = Pequ + P alpha e-t/tau alpha + P beta e-t/tau beta, where Pt is the pressure at time t, Pequ is the equilibrium pressure after...... dilatation, P alpha and P beta are pressure decay, and tau alpha and tau beta are time constants. The time constants have previously proved independent of the way the dilatation is performed. The urethral stress relaxation obtained in 10 healthy women before and after pudendal nerve blockade was analysed...... by the mathematical model and the pressure parameters and time constants determined. The fast time constant, tau beta, was reduced by the nerve blockade, whereas tau alpha was unaffected, however, both P alpha and P beta were reduced. No single stress relaxation parameter can therefore be related to the muscle...

  17. Effects of cigarette smoke exposure on nicotinic acetylcholine receptor subunits {alpha}7 and {beta}2 in the sudden infant death syndrome (SIDS) brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Machaalani, Rita, E-mail: rita.machaalani@sydney.edu.au [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia); Say, Meichien [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); Waters, Karen A. [Department of Medicine, The University of Sydney, NSW 2006 (Australia); Bosch Institute, The University of Sydney, NSW 2006 (Australia); The Children' s Hospital at Westmead, NSW 2145 (Australia)

    2011-12-15

    It is postulated that nicotine, as the main neurotoxic constituent of cigarette smoke, influences SIDS risk through effects on nicotinic acetylcholine receptors (nAChRs) in brainstem nuclei that control respiration and arousal. This study compared {alpha}7 and {beta}2 nAChR subunit expression in eight nuclei of the caudal and rostral medulla and seven nuclei of the pons between SIDS (n = 46) and non-SIDS infants (n = 14). Evaluation for associations with known SIDS risk factors included comparison according to whether infants had a history of exposure to cigarette smoke in the home, and stratification for sleep position and gender. Compared to non-SIDS infants, SIDS infants had significantly decreased {alpha}7 in the caudal nucleus of the solitary tract (cNTS), gracile and cuneate nuclei, with decreased {beta}2 in the cNTS and increased {beta}2 in the facial. When considering only the SIDS cohort: 1-cigarette smoke exposure was associated with increased {alpha}7 in the vestibular nucleus and increased {beta}2 in the rostral dorsal motor nucleus of the vagus, rNTS and Cuneate, 2-there was a gender interaction for {alpha}7 in the gracile and cuneate, and {beta}2 in the cNTS and rostral arcuate nucleus, and 3-there was no effect of sleep position on {alpha}7, but prone sleep was associated with decreased {beta}2 in three nuclei of the pons. In conclusion, SIDS infants demonstrate differences in expression of {alpha}7 and {beta}2 nAChRs within brainstem nuclei that control respiration and arousal, which is independent on prior history of cigarette smoke exposure, especially for the NTS, with additional differences for smoke exposure ({beta}2), gender ({alpha}7 and {beta}2) and sleep position ({beta}2) evident. -- Highlights: Black-Right-Pointing-Pointer The 'normal' response to smoke exposure is decreased {alpha}7 and {beta}2 in certain nuclei. Black-Right-Pointing-Pointer SIDS infants have decreased {alpha}7 in cNTS, Grac and Cun. Black

  18. Brain activation by short-term nicotine exposure in anesthetized wild-type and beta2-nicotinic receptors knockout mice: a BOLD fMRI study

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, S.V.; Changeux, J.P.; Granon, S. [Unite de Neurobiologie Integrative du Systeme Cholinergique, URA CNRS 2182, Institut Pasteur, Departement de Neuroscience, 25 rue du Dr Roux, 75015 Paris (France); Amadon, A.; Giacomini, E.; Le Bihan, D. [Service Hospitalier Frederic Joliot, 4 place du general Leclerc, 91400 Orsay (France); Wiklund, A. [Section of Anaesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm (Sweden)

    2009-07-01

    Rationale: The behavioral effects of nicotine and the role of the beta2-containing nicotinic receptors in these behaviors are well documented. However, the behaviors altered by nicotine rely on the functioning on multiple brain circuits where the high-affinity {beta}2-containing nicotinic receptors ({beta}2*nAChRs) are located. Objectives We intend to see which brain circuits are activated when nicotine is given in animals naive for nicotine and whether the {beta}2*nAChRs are needed for its activation of the blood oxygen level dependent (BOLD) signal in all brain areas. Materials and methods: We used functional magnetic resonance imaging (fMRI) to measure the brain activation evoked by nicotine (1 mg/kg delivered at a slow rate for 45 min) in anesthetized C57BL/6J mice and {beta}2 knockout (KO) mice. Results: Acute nicotine injection results in a significant increased activation in anterior frontal, motor, and somatosensory cortices and in the ventral tegmental area and the substantia nigra. Anesthetized mice receiving no nicotine injection exhibited a major decreased activation in all cortical and subcortical structures, likely due to prolonged anesthesia. At a global level, {beta}2 KO mice were not rescued from the globally declining BOLD signal. However, nicotine still activated regions of a meso-cortico-limbic circuit likely via {alpha}7 nicotinic receptors. Conclusions: Acute nicotine exposure compensates for the drop in brain activation due to anesthesia through the meso-cortico-limbic network via the action of nicotine on {beta}2*nAChRs. The developed fMRI method is suitable for comparing responses in wild-type and mutant mice. (authors)

  19. Liver X receptors alpha and beta regulate renin expression in vivo

    NARCIS (Netherlands)

    Morello, Fulvio; de Boer, Rudolf A; Steffensen, Knut R; Gnecchi, Massimiliano; Chisholm, Jeffrey W; Boomsma, Frans; Anderson, Leonard M; Lawn, Richard M; Gustafsson, Jan-Ake; Lopez-Ilasaca, Marco; Pratt, Richard E; Dzau, Victor J

    2005-01-01

    The renin-angiotensin-aldosterone system controls blood pressure and salt-volume homeostasis. Renin, which is the first enzymatic step of the cascade, is critically regulated at the transcriptional level. In the present study, we investigated the role of liver X receptor alpha (LXR(alpha)) and LXR(b

  20. Essential domain of receptor tyrosine phosphatase beta (RPTPbeta) for interaction with Helicobacter pylori vacuolating cytotoxin

    DEFF Research Database (Denmark)

    Yahiro, Kinnosuke; Wada, Akihiro; Yamasaki, Eiki;

    2004-01-01

    Helicobacter pylori produces a potent exotoxin, VacA, which causes progressive vacuolation as well as gastric injury. Although VacA was able to interact with two receptor-like protein tyrosine phosphatases, RPTPbeta and RPTPalpha, RPTPbeta was found to be responsible for gastric damage caused...

  1. Interaction of Protease-Activated Receptor 2 with G Proteins and Beta-Arrestin 1 Studied by Bioluminescence Resonance Energy Transfer

    Directory of Open Access Journals (Sweden)

    Mohammed Akli eAyoub

    2013-12-01

    Full Text Available G protein-coupled receptors (GPCRs are well recognized as being able to activate several signaling pathways through the activation of different G proteins as well as other signaling proteins such as beta-arrestins. Therefore, understanding how such multiple GPCR-mediated signaling can be integrated constitute an important aspect. Here, we applied bioluminescence resonance energy transfer (BRET to shed more light on the G protein coupling profile of trypsin receptor, or protease-activated receptor 2 (PAR2, and its interaction with beta-arrestin1. Using YFP and Rluc fusion constructs expressed in COS-7 cells, BRET data revealed a pre-assembly of PAR2 with both Galphai1 and Galphao and a rapid and transient activation of these G proteins upon receptor activation. In contrast, no preassembly of PAR2 with Galpha12 could be detected and their physical association can be measured with a very slow and sustained kinetics similar to that of beta-arrestin1 recruitment. These data demonstrate the coupling of PAR2 with Galphai1, Galphao and Galpha12 in COS-7 cells with differences in the kinetics of GPCR-G protein coupling, a parameter that very likely influences the cellular response. Moreover, this further illustrates that preassembly or agonist-induced G protein interaction depends on receptor-G protein pairs indicating another level of complexity and regulation of the signaling of GPCR-G protein complexes and its multiplicity.

  2. Computational Studies of Beta Amyloid (Aβ42 with p75NTR Receptor: A Novel Therapeutic Target in Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Shine Devarajan

    2014-01-01

    Full Text Available Alzheimer’s disease is a neurodegenerative disorder characterized by the accumulation of beta amyloid plaques (Aβ which can induce neurite degeneration and progressive dementia. It has been identified that neuronal apoptosis is induced by binding of Aβ42 to pan neurotrophin receptor (p75NTR and gave the possibility that beta amyloid oligomer is a ligand for p75NTR. However, the atomic contact point responsible for molecular interactions and conformational changes of the protein upon binding was not studied in detail. In view of this, we conducted a molecular docking and simulation study to investigate the binding behaviour of Aβ42 monomer with p75NTR ectodomain. Furthermore, we proposed a p75NTR-ectodomain-Aβ42 complex model. Our data revealed that, Aβ42 specifically recognizes CRD1 and CRD2 domains of the receptor and formed a “cap” like structure at the N-terminal of receptor which is stabilized by a network of hydrogen bonds. These findings are supported by molecular dynamics simulation that Aβ42 showed distinct structural alterations at N- and C-terminal regions due to the influence of the receptor binding site. Overall, the present study gives more structural insight on the molecular interactions of beta amyloid protein involved in the activation of p75NTR receptor.

  3. Developmental Changes is Expression of Beta-Adrenergic Receptors in Cultures of C2C12 Skeletal Muscle Cells

    Science.gov (United States)

    Young, Ronald B.; Bridge, K. Y.; Vaughn, J. R.

    2000-01-01

    beta-Adrenergic receptor (bAR) agonists have been reported to modulate growth in several mammalian and avian species, and bAR agonists presumably exert their physiological action on skeletal muscle cells through this receptor. Because of the importance of bAR regulation on muscle protein metabolism in muscle cells, the objectives of this study were to determine the developmental expression pattern of the bAR population in C2C12 skeletal muscle cells, and to analyze changes in both the quantity and isoform expression of the major muscle protein, myosin. The number of bAR in mononucleated C2C12 cells was approximately 8,000 bAR per cell, which is comparable with the population reported in several other nonmuscle cell types. However, the bar population increased after myoblast fusion to greater than 50,000 bAR per muscle cell equivalent. The reasons for this apparent over-expression of bAR in C2C12 cells is not known. The quantity of myosin also increased after C2C12 myoblast fusion, but the quantity of myosin was less than that reported in primary muscle cell cultures. Finally, at least five different isoforms of myosin heavy chain could be resolved in C2C12 cells, and three of these exhibited either increased or decreased developmental regulation relative to the others. Thus, C2C12 myoblasts undergo developmental regulation of bAR population and myosin heavy chain isoform expression.

  4. Gut-homing CD4+ T cell receptor alpha beta+ T cells in the pathogenesis of murine inflammatory bowel disease

    DEFF Research Database (Denmark)

    Rudolphi, A; Boll, G; Poulsen, S S;

    1994-01-01

    We studied which T cell subsets from the gut-associated lymphoid tissue (GALT) can migrate out of the gut mucosa and repopulate GALT compartments of an immunodeficient (semi)syngeneic host. Many distinct lymphocyte subsets were found in GALT of immunocompetent H-2d (BALB/c, BALB/cdm2, C.B-17......+/+) mice. No antigen receptor-expressing lymphoid cells were found in GALT of congenic C.B-17 scid/scid (scid) mice. The heterotopic transplantation of a full-thickness gut wall graft from the ileum or colon of immunocompetent (C.B-17+/+, BALB/cdm2) donor mice onto immunodeficient scid mice selectively...... reconstituted a CD3+ T cell receptor alpha beta+ CD4+ T cell subset. CD4+ cells of this subset expressed the surface phenotype of mucosa-seeking, memory T cells. In the immunodeficient scid host, this gut-derived CD4+ T cell subset was found in spleen, peritoneal cavity, mesenteric lymph nodes (LN), epithelial...

  5. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    OpenAIRE

    Niu,Ai-qin; Xie, Liang-jun; Wang, Hui; Bing ZHU; Wang, Sheng-Qi

    2016-01-01

    Background Estrogen receptors (ERs) are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal appr...

  6. Receptor Density Is Key to the Alpha2/Beta Interferon Differential Activities

    OpenAIRE

    Moraga, I.; Harari, D.; Schreiber, G.; Uze, G.; Pellegrini, S.

    2009-01-01

    Multiple type I interferons (IFN-α/β) elicit Jak/Stat activation, rapid gene induction, and pleiotropic effects, such as differentiation, antiviral protection, and blocks in proliferation, which are dependent on the IFN subtype and the cellular context. To date, ligand- and receptor-specific molecular determinants underlying IFN-α/β differential activities or potencies have been well characterized. To analyze cellular determinants that impact subtype-specific potency, human fibrosarcoma U5A-d...

  7. The evolving role of oestrogen receptor beta in clinical breast cancer

    OpenAIRE

    Speirs, Valerie

    2008-01-01

    Controversy surrounds the potential clinical importance of oestrogen receptor (ER)β in breast cancer, and three recent papers have sought to resolve this. In the present issue of Breast Cancer Research Novelli and colleagues explored the significance of ERβ1 expression in 936 breast cancer patients, and they showed diverse relationships according to lymph node status. A second paper examined 442 breast cancers in which ERβ1 was an independent predictor of recurrence, disease-free survival and...

  8. Interleukin 1 receptor antagonist mediates the beneficial effects of systemic interferon beta in mice: implications for rheumatoid arthritis

    NARCIS (Netherlands)

    M. Corr; D.L. Boyle; L.M. Ronacher; B.R. Lew; L.G. van Baarsen; P.P. Tak; G.S. Firestein

    2011-01-01

    Objectives Interferon beta (IFN beta) therapy is effective in multiple sclerosis and murine models of arthritis. Surprisingly, systemic IFN beta treatment induces only minimal improvement in rheumatoid arthritis (RA). To explain this paradox, the authors evaluated the mechanism of IFN beta benefit i

  9. Modeling the interactions of a peptide-major histocompatibility class I ligand with its receptors. II. Cross-reaction between a monoclonal antibody and two alpha beta T cell receptors

    DEFF Research Database (Denmark)

    Rognan, D; Engberg, J; Stryhn, A;

    2000-01-01

    -peptide pair into the Fab combining site. Interestingly, the most energetically favored binding mode shows numerous analogies to the recently determined recognition of class I MHC-peptide complexes by alpha beta T cell receptors (TCRs). The pSAN13.4.1 also binds diagonally across the MHC binding groove...

  10. Ryanodine receptor type I and nicotinic acid adenine dinucleotide phosphate receptors mediate Ca2+ release from insulin-containing vesicles in living pancreatic beta-cells (MIN6).

    Science.gov (United States)

    Mitchell, Kathryn J; Lai, F Anthony; Rutter, Guy A

    2003-03-28

    We have demonstrated recently (Mitchell, K. J., Pinton, P., Varadi, A., Tacchetti, C., Ainscow, E. K., Pozzan, T., Rizzuto, R., and Rutter, G. A. (2001) J. Cell Biol. 155, 41-51) that ryanodine receptors (RyR) are present on insulin-containing secretory vesicles. Here we show that pancreatic islets and derived beta-cell lines express type I and II, but not type III, RyRs. Purified by subcellular fractionation and membrane immuno-isolation, dense core secretory vesicles were found to possess a similar level of type I RyR immunoreactivity as Golgi/endoplasmic reticulum (ER) membranes but substantially less RyR II than the latter. Monitored in cells expressing appropriately targeted aequorins, dantrolene, an inhibitor of RyR I channels, elevated free Ca(2+) concentrations in the secretory vesicle compartment from 40.1 +/- 6.7 to 90.4 +/- 14.8 microm (n = 4, p < 0.01), while having no effect on ER Ca(2+) concentrations. Furthermore, nicotinic acid adenine dinucleotide phosphate (NAADP), a novel Ca(2+)-mobilizing agent, decreased dense core secretory vesicle but not ER free Ca(2+) concentrations in permeabilized MIN6 beta-cells, and flash photolysis of caged NAADP released Ca(2+) from a thapsigargin-insensitive Ca(2+) store in single MIN6 cells. Because dantrolene strongly inhibited glucose-stimulated insulin secretion (from 3.07 +/- 0.51-fold stimulation to no significant glucose effect; n = 3, p < 0.01), we conclude that RyR I-mediated Ca(2+)-induced Ca(2+) release from secretory vesicles, possibly potentiated by NAADP, is essential for the activation of insulin secretion.

  11. Interleukin-1-mediated febrile responses in mice and interleukin-1 beta activation of NFkappaB in mouse primary astrocytes, involves the interleukin-1 receptor accessory protein.

    Science.gov (United States)

    Zetterström, M; Lundkvist, J; Malinowsky, D; Eriksson, G; Bartfai, T

    1998-06-01

    The endogenous pyrogen interleukin-1 (IL-1) is considered as one of the key molecules in orchestrating the host response of injury and inflammation. IL-1 exerts its effects upon binding to the type I IL-1 receptor (IL-1RI). The IL-1-IL-1RI complex is further thought to associate with the IL-1 receptor accessory protein (IL-1RAcP), which is suggested to be important for most IL-1 signal transduction pathways. With the aim of investigating the importance of the IL-1RAcP in IL-1 signalling, IL-1alpha and IL-1beta induced febrile responses and IL-1beta-mediated activation of NFkappaB in primary astrocyte cultures were examined using IL-1RAcP-deficient (IL-1RAcP KO) and wild type mice, respectively. It was shown that neither recombinant rat IL-1alpha (rrIL-1alpha, 25 microg/kg), recombinant rat IL-1beta (rrIL-1beta, 40 microg/kg) nor recombinant human IL-1beta (rhIL-1beta, 50 microg/kg) injected i.p. could elicit febrile responses in the IL-1RAcP-deficient mice, while the same doses of rrIL-1alpha/beta or rhIL-1beta injected into wild type mice caused normal fever responses. A febrile response could be induced in the IL-1RAcP-deficient mice by i.p. administration of E. coli lipopolysaccharide (LPS, 50 microg/kg) and this response was similar to that obtained in wild type mice. Furthermore, it was shown that rhIL-1beta activated, in a concentration-dependent manner, nuclear translocation of the transcriptional nuclear factor kappa B (NFkappaB) in primary astrocyte cultures prepared from wild type mice, whereas no IL-1beta-induced translocation of NFkappaB could be detected in cultures prepared from IL-1RAcP-deficient mice, as revealed by electrophoretic mobility shift assay (EMSA). The rhIL-1beta-induced NFkappaB complexes were shown to contain p50 but no, or very little, p65 and cRel immunoreactive proteins.

  12. Alternative-splicing in the exon-10 region of GABA(A receptor beta(2 subunit gene: relationships between novel isoforms and psychotic disorders.

    Directory of Open Access Journals (Sweden)

    Cunyou Zhao

    Full Text Available BACKGROUND: Non-coding single nucleotide polymorphisms (SNPs in GABRB2, the gene for beta(2-subunit of gamma-aminobutyric acid type A (GABA(A receptor, have been associated with schizophrenia (SCZ and quantitatively correlated to mRNA expression and alternative splicing. METHODS AND FINDINGS: Expression of the Exon 10 region of GABRB2 from minigene constructs revealed this region to be an "alternative splicing hotspot" that readily gave rise to differently spliced isoforms depending on intron sequences. This led to a search in human brain cDNA libraries, and the discovery of two novel isoforms, beta(2S1 and beta(2S2, bearing variations in the neighborhood of Exon-10. Quantitative real-time PCR analysis of postmortem brain samples showed increased beta(2S1 expression and decreased beta(2S2 expression in both SCZ and bipolar disorder (BPD compared to controls. Disease-control differences were significantly correlated with SNP rs187269 in BPD males for both beta(2S1 and beta(2S2 expressions, and significantly correlated with SNPs rs2546620 and rs187269 in SCZ males for beta(2S2 expression. Moreover, site-directed mutagenesis indicated that Thr(365, a potential phosphorylation site in Exon-10, played a key role in determining the time profile of the ATP-dependent electrophysiological current run-down. CONCLUSION: This study therefore provided experimental evidence for the importance of non-coding sequences in the Exon-10 region in GABRB2 with respect to beta(2-subunit splicing diversity and the etiologies of SCZ and BPD.

  13. Advances in Renin-Angiotensin System Blockades in Treating Metabolic Syndrome%肾素-血管紧张素系统阻断剂治疗代谢综合征的进展

    Institute of Scientific and Technical Information of China (English)

    张凤; 周华梅; 张霞

    2012-01-01

    代谢综合征以胰岛素抵抗为主要特征,是心血管疾病的危险因素.非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)是代谢综合征在肝脏的表现.肾素-血管紧张素系统(renin-angiotensin system,RAS)的激活参与了代谢综合征的发生、发展,阻断RAS的激活是代谢综合征的治疗途径之一.RAS阻断剂包括血管紧张素转换酶抑制剂(angiotensin converting enzyme inhibitor,ACEI)和血管紧张素Ⅱ受体拮抗剂(angiotensin receptor blockade,ARB),可降低血压、改善胰岛β细胞功能和胰岛素抵抗,但RAS阻断剂对NAFLD的疗效尚存在争议.该文就RAS阻断剂治疗代谢综合征的进展进行了综述.%Insulin resistance is a key characteristic of metabolic syndrome, which is considered as a predictor of cardiovascular diseases. Non - alcoholic fatty liver disease (NAFLD) is a hepatic manifestation of metabolic syndrome. The activation of renin - angiotensin system (RAS) is involved in the development of metabolic syndrome. The inhibition of RAS activation is an effective treatment of metabolic syndrome. RAS blockades, including angiotensin converting enzyme inhibitor (ACEI) and angiotensin receptor blockade (ARB), can decrease blood pressure, improve islet beta - cell function and insulin resistance. However, there is still a controversy about the effect of RAS blockades on NAFLD. In this article, current evidence concerning RAS blockades in the treatment of metabolic syndrome will be reviewed.

  14. Intersubunit bridge formation governs agonist efficacy at nicotinic acetylcholine alpha4beta2 receptors

    DEFF Research Database (Denmark)

    Rohde, Line Aagot Hede; Ahring, Philip Kiær; Jensen, Marianne Lerbech;

    2012-01-01

    The a4ß2 subtype of the nicotinic acetylcholine receptor (nAChR) has been pursued as a drug target for treatment of psychiatric and neurodegenerative disorders and smoking cessation aids for decades. Still, a thorough understanding of structure-function relationships of a4ß2 agonists is lacking....... Using binding experiments, electrophysiology and X-ray crystallography we have investigated a consecutive series of five prototypical pyridine-containing agonists derived from 1-(pyridin-3-yl)-1,4-diazepane. A correlation between binding affinities at a4ß2 and the acetylcholine binding protein from...

  15. Acetylcholine release in mouse hippocampal CA1 preferentially activates inhibitory-selective interneurons via alpha4 beta2* nicotinic receptor activation

    Directory of Open Access Journals (Sweden)

    L. Andrew Bell

    2015-04-01

    Full Text Available Acetylcholine (ACh release onto nicotinic receptors directly activates subsets of inhibitory interneurons in hippocampal CA1. However, the specific interneurons activated and their effect on the hippocampal network is not completely understood. Therefore, we investigated subsets of hippocampal CA1 interneurons that respond to ACh release through the activation of nicotinic receptors and the potential downstream effects this may have on hippocampal CA1 network function. ACh was optogenetically released in mouse hippocampal slices by expressing the excitatory optogenetic protein oChIEF-tdTomato in medial septum/diagonal band of Broca cholinergic neurons using Cre recombinase-dependent adeno-associated viral mediated transfection. The actions of optogenetically released ACh were assessed on both pyramidal neurons and different interneuron subtypes via whole cell patch clamp methods. Vasoactive intestinal peptide (VIP-expressing interneurons that selectively innervate other interneurons (VIP/IS were excited by ACh through the activation of nicotinic receptors containing alpah4 and beta2 subunits (alpha4 beta2*. ACh release onto VIP/IS was presynaptically inhibited by M2 muscarinic autoreceptors. ACh release produced spontaneous inhibitory postsynaptic current (sIPSC barrages blocked by dihydro-beta-erythroidine in interneurons but not pyramidal neurons. Optogenetic suppression of VIP interneurons did not inhibit these sIPSC barrages suggesting other interneuron-selective interneurons were also excited by 42* nicotinic receptor activation. In contrast, interneurons that innervate pyramidal neuron perisomatic regions were not activated by ACh release onto nicotinic receptors. Therefore, we propose ACh release in CA1 facilitates disinhibition through activation of 42* nicotinic receptors on interneuron-selective interneurons whereas interneurons that innervate pyramidal neurons are less affected by nicotinic receptor activation.

  16. c-fos gene induction by interleukin 2: identification of the critical cytoplasmic regions within the interleukin 2 receptor beta chain.

    OpenAIRE

    Hatakeyama, M; Kawahara, A; Mori, H.; Shibuya, H.; Taniguchi, T.

    1992-01-01

    Interleukin 2 (IL-2) plays a critical role in the growth and differentiation of lymphoid cells. The IL-2 signal is delivered intracellularly by the IL-2 receptor beta chain (IL-2R beta); however, the mechanism by which the signal reaches the nucleus remains unclear. In this study, we demonstrate the rapid activation of c-fos protooncogene transcription by IL-2 and provide evidence that the serum-responsive element (SRE) within the c-fos promoter is responsible for the activation in a murine p...

  17. A novel missense mutation in oncostatin M receptor beta causing primary localized cutaneous amyloidosis.

    Science.gov (United States)

    Saeedi, Marjan; Ebrahim-Habibi, Azadeh; Haghighi, Alireza; Zarrabi, Fariba; Amoli, Mahsa M; Robati, Reza M

    2014-01-01

    Primary localized cutaneous amyloidosis (PLCA) is a chronic skin disorder, caused by amyloid material deposition in the upper dermis. Autosomal dominant PLCA has been mapped earlier to pathogenic missense mutations in the OSMR gene, which encodes the oncostatin M receptor ß subunit (OSMRß). OSMRß is interleukin-6 family cytokine receptors and possesses two ligands, oncostatin M and interleukin-31, which both have biologic roles in inflammation and keratinocyte cell proliferation, differentiation, and apoptosis. Here, we identified a new OSMR mutation in a Kurdish family for the first time. Blood samples were taken from all the affected individuals in the family. DNA extraction was performed using salting out technique. Primers were designed for intron flanking individual exons of OSMR gene which were subjected to direct sequencing after PCR amplification for each sample. Sequencing showed a C/T substitution at position 613 in the proband. This mutation results in an L613S (leucine 613 to serine) amino acid change. The identified mutation was observed in all affected family members but not in 100 ethnically matched healthy controls. Elucidating the molecular basis of familial PLCA provides new insight into mechanisms of itch in human skin and may lead to new therapeutic targets for pruritus. PMID:25054142

  18. A role for Peroxisome Proliferator-Activated Receptor Beta in T cell development

    Science.gov (United States)

    Mothe-Satney, Isabelle; Murdaca, Joseph; Sibille, Brigitte; Rousseau, Anne-Sophie; Squillace, Raphaëlle; Le Menn, Gwenaëlle; Rekima, Akila; Larbret, Frederic; Pelé, Juline; Verhasselt, Valérie; Grimaldi, Paul A.; Neels, Jaap G.

    2016-01-01

    Metabolism plays an important role in T cell biology and changes in metabolism drive T cell differentiation and fate. Most research on the role of metabolism in T lymphocytes focuses on mature T cells while only few studies have investigated the role of metabolism in T cell development. In this study, we report that activation or overexpression of the transcription factor Peroxisome Proliferator-Activated Receptor β (PPARβ) increases fatty acid oxidation in T cells. Furthermore, using both in vivo and in vitro models, we demonstrate that PPARβ activation/overexpression inhibits thymic T cell development by decreasing proliferation of CD4−CD8− double-negative stage 4 (DN4) thymocytes. These results support a model where PPARβ activation/overexpression favours fatty acid- instead of glucose-oxidation in developing T cells, thereby hampering the proliferative burst normally occurring at the DN4 stage of T cell development. As a consequence, the αβ T cells that are derived from DN4 thymocytes are dramatically decreased in peripheral lymphoid tissues, while the γδ T cell population remains untouched. This is the first report of a direct role for a member of the PPAR family of nuclear receptors in the development of T cells. PMID:27680392

  19. A Novel Missense Mutation in Oncostatin M Receptor Beta Causing Primary Localized Cutaneous Amyloidosis

    Directory of Open Access Journals (Sweden)

    Marjan Saeedi

    2014-01-01

    Full Text Available Primary localized cutaneous amyloidosis (PLCA is a chronic skin disorder, caused by amyloid material deposition in the upper dermis. Autosomal dominant PLCA has been mapped earlier to pathogenic missense mutations in the OSMR gene, which encodes the oncostatin M receptor ß subunit (OSMRß. OSMRß is interleukin-6 family cytokine receptors and possesses two ligands, oncostatin M and interleukin-31, which both have biologic roles in inflammation and keratinocyte cell proliferation, differentiation, and apoptosis. Here, we identified a new OSMR mutation in a Kurdish family for the first time. Blood samples were taken from all the affected individuals in the family. DNA extraction was performed using salting out technique. Primers were designed for intron flanking individual exons of OSMR gene which were subjected to direct sequencing after PCR amplification for each sample. Sequencing showed a C/T substitution at position 613 in the proband. This mutation results in an L613S (leucine 613 to serine amino acid change. The identified mutation was observed in all affected family members but not in 100 ethnically matched healthy controls. Elucidating the molecular basis of familial PLCA provides new insight into mechanisms of itch in human skin and may lead to new therapeutic targets for pruritus.

  20. Estrogen receptor beta activation prevents glucocorticoid receptor-dependent effects of the central nucleus of the amygdala on behavior and neuroendocrine function.

    Science.gov (United States)

    Weiser, Michael J; Foradori, Chad D; Handa, Robert J

    2010-06-01

    Neuropsychiatric disorders such as anxiety and depression have formidable economic and societal impacts. A dysregulation of the hypothalamo-pituitary-adrenal (HPA) axis leading to elevated endogenous glucocorticoid levels is often associated with such disorders. Chronically high glucocorticoid levels may act upon the central nucleus of the amygdala (CeA) to alter normally adaptive responses into those that are maladaptive and detrimental. In addition to glucocorticoids, other steroid hormones such as estradiol and androgens can also modify hormonal and behavioral responses to threatening stimuli. In particular, estrogen receptor beta (ERbeta) agonists have been shown to be anxiolytic. Consequently, these experiments addressed the hypothesis that the selective stimulation of glucocorticoid receptor (GR) in the CeA would increase anxiety-like behaviors and HPA axis reactivity to stress, and further, that an ERbeta agonist could modulate these effects. Young adult female Sprague-Dawley rats were ovariectomized and bilaterally implanted via stereotaxic surgery with a wax pellet containing the selective GR agonist RU28362 or a blank pellet, to a region just dorsal to the CeA. Four days later, animals were administered the ERbeta agonist S-DPN or vehicle (with four daily sc injections). Anxiety-type behaviors were measured using the elevated plus maze (EPM). Central RU28362 implants caused significantly higher anxiety-type behaviors in the EPM and greater plasma CORT levels than controls given a blank central implant. Moreover, S-DPN treated animals, regardless of type of central implant, displayed significantly lower anxiety-type behaviors and post-EPM plasma CORT levels than vehicle treated controls or vehicle treated animals implanted with RU28362. These results indicate that selective activation of GR within the CeA is anxiogenic, and peripheral administration of an ERbeta agonist can overcome this effect. These data suggest that estradiol signaling via ERbeta

  1. Elevated N-terminal pro-brain natriuretic peptide levels predict an enhanced anti-hypertensive and anti-proteinuric benefit of dietary sodium restriction and diuretics, but not angiotensin receptor blockade, in proteinuric renal patients

    NARCIS (Netherlands)

    Slagman, Maartje C. J.; Waanders, Femke; Vogt, Liffert; Damman, Kevin; Hemmelder, Marc; Navis, Gerjan; Laverman, Gozewijn D.

    2012-01-01

    Background. Renin angiotensin aldosterone system (RAAS) blockade only partly reduces blood pressure, proteinuria and renal and cardiovascular risk in chronic kidney disease (CKD) but often requires sodium targeting [i.e. low sodium diet (LS) and/or diuretics] for optimal efficacy. However, both unde

  2. Prediction of selective estrogen receptor beta agonist using open data and machine learning approach

    Directory of Open Access Journals (Sweden)

    Niu AQ

    2016-07-01

    Full Text Available Ai-qin Niu,1 Liang-jun Xie,2 Hui Wang,1 Bing Zhu,1 Sheng-qi Wang3 1Department of Gynecology, the First People’s Hospital of Shangqiu, Shangqiu, Henan, People’s Republic of China; 2Department of Image Diagnoses, the Third Hospital of Jinan, Jinan, Shandong, People’s Republic of China; 3Department of Mammary Disease, Guangdong Provincial Hospital of Chinese Medicine, the Second Clinical College of Guangzhou University of Chinese Medicine, Guangzhou, People’s Republic of China Background: Estrogen receptors (ERs are nuclear transcription factors that are involved in the regulation of many complex physiological processes in humans. ERs have been validated as important drug targets for the treatment of various diseases, including breast cancer, ovarian cancer, osteoporosis, and cardiovascular disease. ERs have two subtypes, ER-α and ER-β. Emerging data suggest that the development of subtype-selective ligands that specifically target ER-β could be a more optimal approach to elicit beneficial estrogen-like activities and reduce side effects. Methods: Herein, we focused on ER-β and developed its in silico quantitative structure-activity relationship models using machine learning (ML methods. Results: The chemical structures and ER-β bioactivity data were extracted from public chemogenomics databases. Four types of popular fingerprint generation methods including MACCS fingerprint, PubChem fingerprint, 2D atom pairs, and Chemistry Development Kit extended fingerprint were used as descriptors. Four ML methods including Naïve Bayesian classifier, k-nearest neighbor, random forest, and support vector machine were used to train the models. The range of classification accuracies was 77.10% to 88.34%, and the range of area under the ROC (receiver operating characteristic curve values was 0.8151 to 0.9475, evaluated by the 5-fold cross-validation. Comparison analysis suggests that both the random forest and the support vector machine are superior

  3. Radiolabeled high affinity peptidomimetic antagonist selectively targets {alpha}{sub v}{beta}{sub 3} receptor-positive tumor in mice

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Beom-Su [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Lim, Esther [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Hee Park, Seung [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Shin, In Soo [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Danthi, S. Narasimhan [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Hwang, In Sook [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Le, Nhat [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Yu, Sarah [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Xie Jianwu [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Li, King C.P. [Department of Radiology, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Carrasquillo, Jorge A. [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States); Paik, Chang H. [Department of Nuclear Medicine, Warren G. Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892 (United States)]. E-mail: cpaik@mail.nih.gov

    2007-05-15

    Objectives: The aim of this research was to synthesize radiolabeled peptidomimetic integrin {alpha}{sub v}{beta}{sub 3} antagonists that selectively target integrin {alpha}{sub v}{beta}{sub 3} receptor and clear rapidly from the whole body. Methods: Integrin {alpha}{sub v}{beta}{sub 3} antagonists, 4-[2-(3,4,5,6-tetrahydropyrimidine-2-ylamino) ethyloxy]benzoyl-2-(S)-aminoethylsulfonyl-amino-{beta}-alanine (IA) and 4-[2-(3,4,5,6-tetrahydro-pyrimidin-2-ylamino)-ethyloxy]benzoyl-2-(S)-[N- (3-amino-neopenta-1-carbamyl)]-aminoethylsulfonylamino-{beta}-alanine hydrochloride (IAC), a hydrophobic carbamate derivative of IA, were conjugated with 2-p-isothiocyanatobenzyl-DOTA at the amino terminus and labeled with {sup 111}In. The {sup 111}In labeled IA and IAC were subjected to in vitro receptor binding, biodistribution and imaging studies using nude mice bearing the receptor-positive M21 human melanoma xenografts. Results: The {sup 111}In-labeled IA (40%) and -IAC (72%) specifically bound in vitro to {alpha}{sub v}{beta}{sub 3} (0.8 {mu}M) at a molar excess. This receptor binding was completely blocked by a molar excess of cold IA to {alpha}{sub v}{beta}{sub 3}. The higher receptor-binding affinity of the {sup 111}In-labeled IAC was reflected in higher tumor uptake and retention: 5.6{+-}1.4 and 4.5{+-}0.7 %ID/g vs. 3.8{+-}0.9 and 2.0{+-}0.3 %ID/g for the {sup 111}In-labeled IA at 0.33 and 2 h. The tumor uptakes were inhibited by the co-injection of 200 {mu}g of IA, indicating that the uptake was receptor mediated. These antagonists were excreted primarily via the renal system. The {sup 111}In activity retained in the whole body was quite comparable between the {sup 111}In-labeled IA (24% ID) and the {sup 111}In-labeled IAC (33% ID) at 2 h. The higher peak tumor uptake and longer retention resulted in higher tumor-to-background ratios for the {sup 111}In-labeled IAC at 2 h with 9.7, 2.3, 0.8, 1.9, 7.1, 2.2, 0.9, 3.7 and 9.9 for blood, liver, kidney, lung, heart, stomach

  4. Disruption of estrogen receptor beta in mice brain results in pathological alterations resembling Alzheimer disease

    Institute of Scientific and Technical Information of China (English)

    Qing-hong ZHANG; Yan-hong HUANG; Yu-zhen HU; Geng-ze WEI; Xue-feng HAN; Shun-yan LU; Yu-feng ZHAO

    2004-01-01

    AIM: To study the pathological characteristics of the mice with estrogen receptor β (ERβ) disruption in brain.METHODS: Immunohistochemistry method was applied in the study. RESULTS: β-Amyloid peptide(Aβ42) and apolipoprotein E (ApoE) immunoreactive substances were accumulated notably in cortex and limbic structures such as the hippocampus and amygdala in brain, resembling the pathological changes of human Alzheimer disease (AD). Aβ formed cloudy-like deposits in parenchyma of brain, while apoE also deposited along or surrounding the blood vessels. CONCLUSIONS: ERβ is crucial to the development of neural degenerative disease, so modulation of Aβ metabolism via ERβ signal pathway might be beneficial for AD prevention or therapy.

  5. Relationship between Beta Estrogen Receptor Polymorphism and Psychosocial Stress on Menopausal Women

    Directory of Open Access Journals (Sweden)

    Elizabet Catherine Jusuf

    2016-08-01

    Full Text Available Menopause is a normal stage of development experienced by elderly women. This study aimed to evaluate the association between polymorphisms of ERα & ERβ and the incidence of psychosocial stress on menopausal women. This research was conducted in BLU dr. Wahidin Sudirohusodo and affiliate hospitals of Department of Obstetrics and Gynecology Medical Faculty of Hasanuddin University in Makassar, using cross-sectional design. Obtained sample of 102 subjects who met the inclusion criteria and examined polymorphisms receptors ERβ. Data were statistically analyzed using the chi square test with p value <0.05. Results showed that respondents who experienced psychosocial stress has the most ERβ polymorphism homozygous dominant AA. There is ERβ polymorphism relationship with the occurrence of psychosocial stress in menopausal women.

  6. Cloning of somatolactin alpha, beta forms and the somatolactin receptor in Atlantic salmon: Seasonal expression profile in pituitary and ovary of maturing female broodstock

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    Taranger Geir

    2008-09-01

    Full Text Available Abstract Background Somatolactin (Sl is a fish specific adenohypophyseal peptide hormone related to growth hormone (Gh. Some species, including salmonids, possess two forms: Sl alpha and Sl beta. The somatolactin receptor (slr is closely related to the growth hormone receptor (ghr. Sl has been ascribed many physiological functions, including a role in sexual maturation. In order to clarify the role of Sl in the sexual maturation of female Atlantic salmon (Salmo salar, the full length cDNAs of slr, Sl alpha and Sl beta were cloned and their expression was studied throughout a seasonal reproductive cycle using real-time quantitative PCR (RTqPCR. Methods Atlantic salmon Sl alpha, Sl beta and slr cDNAs were cloned using a PCR approach. Gene expression of Sl alpha, SL beta and slr was studied using RTqPCR over a 17 month period encompassing pre-vitellogenesis, vitellogenesis, ovulation and post ovulation in salmon females. Histological examination of ovarian samples allowed for the classification according to the degree of follicle maturation into oil drop, primary, secondary or tertiary yolk stage. Results The mature peptide sequences of Sl alpha, Sl beta and slr are highly similar to previously cloned salmonid forms and contained the typical motifs. Phylogenetic analysis of Atlantic salmon Sl alpha and Sl beta shows that these peptides group into the two Sl clades present in some fish species. The Atlantic salmon slr grouped with salmonid slr amongst so-called type I ghr. An increase in pituitary Sl alpha and Sl beta transcripts before and during spawning, with a decrease post-ovulation, and a constant expression level of ovarian slr were observed. There was also a transient increase in Sl alpha and Sl beta in May prior to transfer from seawater to fresh water and ensuing fasting. Conclusion The up-regulation of Sl alpha and Sl beta during vitellogenesis and spawning, with a subsequent decrease post-ovulation, supports a role for Sl during gonadal

  7. Immunolocalization of estrogen receptor beta in the epididymis of mature and immature pigs.

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    M Maggiolini

    2004-03-01

    Full Text Available A growing body of evidence suggests a role of estrogens in the male reproduction via their specific estrogen receptors (ERalpha/ERbeta. Estrogen receptor distribution along the genital tract tissues has been described in different species, but it is unknown in the pig. Therefore, the aim of the present study was to localize ERbeta in the epididymis of mature and immature pigs (aged 2 and 18 months, respectively. Immunohistochemistry was carried out on paraffin-embedded tissues using a mouse anti-human monoclonal IgG against ERbeta as the primary antibody, and a goat anti-mouse biotinylated IgG as the secondary antibody. Avidin-biotin-peroxidase complex was then applied followed by diaminobenzidine. In immature pigs, the epithelial cells from the caput, corpus and cauda epididymis showed no or very weak immunoreactivity for ERbeta, whereas they were all strongly immmunoreactive in mature pigs. A various intensity of immunostaining from weak to strong in the smooth muscle cells as well as in the connective tissue cells were detected in the epididymis of both, young and adult pigs. This is the first report on the cellular localization of ERbeta protein in porcine epidydimis. The present study demonstrated that (1 irrespectively of the epididymal region, the epithelial cells of caput, corpus and cauda epididymis of mature pigs revealed a strong immunoreactivity for ERbeta, and (2 ERbeta expression in the epididymal epithelium is regulated by puberty. Finally, although the biological activity of ERbeta has not yet been established, the results of the present study suggest its involvement in estrogen modulation of pig epididymal function.

  8. Concomitant targeting of EGF receptor, TGF-beta and SRC points to a novel therapeutic approach in pancreatic cancer.

    Directory of Open Access Journals (Sweden)

    Sophie Deharvengt

    Full Text Available To test the hypothesis that concomitant targeting of the epidermal growth factor receptor (EGFR and transforming growth factor-beta (TGF-β may offer a novel therapeutic approach in pancreatic cancer, EGFR silencing by RNA interference (shEGFR was combined with TGF-β sequestration by soluble TGF-β receptor II (sTβRII. Effects on colony formation in 3-dimensional culture, tumor formation in nude mice, and downstream signaling were monitored. In both ASPC-1 and T3M4 cells, either shEGFR or sTβRII significantly inhibited colony formation. However, in ASPC-1 cells, combining shEGFR with sTβRII reduced colony formation more efficiently than either approach alone, whereas in T3M4 cells, shEGFR-mediated inhibition of colony formation was reversed by sTβRII. Similarly, in vivo growth of ASPC-1-derived tumors was attenuated by either shEGFR or sTβRII, and was markedly suppressed by both vectors. By contrast, T3M4-derived tumors either failed to form or were very small when EGFR alone was silenced, and these effects were reversed by sTβRII due to increased cancer cell proliferation. The combination of shEGFR and sTβRII decreased phospho-HER2, phospho-HER3, phoshpo-ERK and phospho-src (Tyr416 levels in ASPC-1 cells but increased their levels in T3M4 cells. Moreover, inhibition of both EGFR and HER2 by lapatinib or of src by SSKI-606, PP2, or dasatinib, blocked the sTβRII-mediated antagonism of colony formation in T3M4 cells. Together, these observations suggest that concomitantly targeting EGFR, TGF-β, and src may constitute a novel therapeutic approach in PDAC that prevents deleterious cross-talk between EGFR family members and TGF-β-dependent pathways.

  9. Variations in maternal care alter corticosterone and 17beta-estradiol levels, estrous cycle and folliculogenesis and stimulate the expression of estrogen receptors alpha and beta in the ovaries of UCh rats

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    Amorim João PA

    2011-12-01

    Full Text Available Abstract Background Variations in maternal care are associated with neonatal stress, hormonal disturbances and reproductive injuries during adulthood. However, the effects of these variations on sex hormones and steroid receptors during ovary development remain undetermined. This study aimed to i