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Sample records for adrenergic receptor gene

  1. β3-Adrenergic receptor gene polymorphism and type 2 diabetes in a Caucasian population

    NARCIS (Netherlands)

    Oeveren van-Dybicz, A.M.; Vonkeman, H.E.; Bon, M.A.M.; Bergh, van den F.A.J.T.M.; Vermes, I.

    2008-01-01

    Aim: The β3-adrenergic receptor (β3-AR) is suspected to play a key role in the regulation of energy balance by increasing lipolysis and thermogenesis. A mutation in the β3-AR gene (Trp64Arg) has been associated with the capacity of weight gain and with early onset of noninsulin dependent diabetes me

  2. Relationship between the Mutation of IRS-1 Gene and β3-adrenergic Receptor Gene

    Institute of Scientific and Technical Information of China (English)

    丁国宪; 沈捷; 陈家伟

    2001-01-01

    Objective To explore the relationship between the mutation of Insulin receptor substrate-1 ( IRS-1) gene and β3-adrenergic receptor (β3-AR) gene associated with insulin resistance, to further elucidate the etiology and pathogenesis of type 2 DM, hypertension and coronary heart disease. Methods 281 Chinese subjects are divided into three groups according to the oral glucose tolerance test (OGTT), The subjects were genotyped for the codon 64 of β3-AR gene, the codon 972 of IRS-1 gene polymorphisms by applying polymerase chain reaction (PCR) restriction fragment-length polymorphisms (RFLP) screening. Results Our study found that there was significantly increased frequency of IRS-1 gene mutation in IGT subjects and type 2 DM patients (P<0.05, 0.01, respectively), increased frequency of β3-AR gene mutation in type 2 DM patients (P<0.01), compared with NGT subjects. After adjusted for age, sex and plasma glucose, the level of insulin was significantly correlated with polymorphism of IRS-1 gene and β3-AR gene (P<0.001 in all ) by multiple regression analysis. In the models of Logistic regression, type 2 DM is closely related to age and family history (OR=3.1966, 1.4670; P=0.0272, 0.009; respectively), and to the polymorphism of β3-AR gene (OR=1.7380, P=0.0356), but not related to the polymorphism of IRS-1 gene. Conclusions These results suggest that mutation of IRS-1 gene may be the risk factor for insulin resistance, whereas mutation of β3-AR gene may be a common risk factor for insulin resistance, obesity, type 2 DM and hypertension.

  3. High-throughput chemiluminometric genotyping of single nucleotide polymorphisms of histamine, serotonin, and adrenergic receptor genes.

    Science.gov (United States)

    Toubanaki, Dimitra K; Christopoulos, Theodore K; Ioannou, Penelope C; Flordellis, Christodoulos S

    2009-02-01

    Several pharmacogenetic studies are focused on the investigation of the relation between the efficacy of various antipsychotic agents (e.g., clozapine) and the genetic profile of the patient with an emphasis on genes that code for neurotransmitter receptors such as histamine, serotonin, and adrenergic receptors. We report a high-throughput method for genotyping of single nucleotide polymorphisms (SNPs) within the genes of histamine H2 receptor (HRH2), serotonin receptor (HTR2A1 and HTR2A2), and beta(3) adrenergic receptor (ADRB3). The method combines the high specificity of allele discrimination by oligonucleotide ligation reaction (OLR) and the superior sensitivity and simplicity of chemiluminometric detection in a microtiter well assay configuration. The genomic region that spans the locus of interest is first amplified by polymerase chain reaction (PCR). Subsequently, an oligonucleotide ligation reaction is performed using a biotinylated common probe and two allele-specific probes that are labeled at the 3' end with digoxigenin and fluorescein. The ligation products are immobilized in polystyrene wells via biotin-streptavidin interaction, and the hybrids are denatured. Detection is accomplished by the addition of alkaline phosphatase-conjugated anti-digoxigenin or anti-fluorescein antibodies in combination with a chemiluminogenic substrate. The ratio of the luminescence signals obtained from digoxigenin and fluorescein indicates the genotype of the sample. The method was applied successfully to the genotyping of 23 blood samples for all four SNPs. The results were in concordance with both PCR-restriction fragment length polymorphism analysis and sequencing.

  4. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    Veldhuis-Vlug, A G; Oei, L; Souverein, P C; Tanck, M W T; Rivadeneira, F; Zillikens, M C; Kamphuisen, P W; Maitland-van der Zee, A H; de Groot, M C H; Hofman, A; Uitterlinden, A G; Fliers, E; de Boer, A; Bisschop, P H

    2015-01-01

    Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rotterdam Stu

  5. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    A.G. Veldhuis-Vlug; L. Oei (Ling); P. Souverein (Patrick); M.W.T. Tanck (Michael); F. Rivadeneira Ramirez (Fernando); M.C. Zillikens (Carola); P.W. Kamphuisen; A-H. Maitland-van der Zee (Anke-Hilse); M.C.H. de Groot; A. Hofman (Albert); A.G. Uitterlinden (André); E. Fliers (Eric); A.C. de Boer (Anthonius); P.H. Bisschop

    2015-01-01

    textabstractSummary: Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in t

  6. Association of polymorphisms in the beta-2 adrenergic receptor gene with fracture risk and bone mineral density

    NARCIS (Netherlands)

    Veldhuis-Vlug, A. G.; Oei, L.; Souverein, P. C.; Tanck, M. W T; Rivadeneira, F.; Zillikens, M. C.; Kamphuisen, P. W.; Maitland - van der Zee, A. H.; de Groot, M. C H; Hofman, A.; Uitterlinden, A. G.; Fliers, E.; de Boer, A.; Bisschop, P. H.

    2015-01-01

    Summary: Signaling through the beta-2 adrenergic receptor (B2AR) on the osteoblast influences bone remodeling in rodents. In the B2AR gene, three polymorphisms influence receptor function. We show that these polymorphisms are not associated with fracture risk or bone mineral density in the UCP, Rott

  7. 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...

  8. Structure of the gene for human. beta. /sub 2/-adrenergic receptor: expression and promoter characterization

    Energy Technology Data Exchange (ETDEWEB)

    Emorine, L.J.; Marullo, S.; Delavier-Klutchko, C.; Kaveri, S.V.; Durieu-Trautmann, O.; Strosberg, A.D.

    1987-10-01

    The genomic gene coding for the human ..beta../sub 2/-adrenergic receptor (..beta../sub 2/AR) from A431 epidermoid cells has been isolated. Transfection of the gene into eukaryotic cells restores a fully active receptor/GTP-binding protein/adenylate cyclase complex with ..beta../sub 2/AR properties. Southern blot analyses with ..beta../sub 2/AR-specific probes show that a single ..beta../sub 2/AR gene is common to various human tissues and that its flanking sequences are highly conserved among humans and between man and rabbit, mouse, and hamster. Functional significance of these regions is supported by the presence of a promoter region (including mRNA cap sites, two TATA boxes, a CAAT box, and three G + C-rich regions that resemble binding sites for transcription factor Sp1) 200-300 base pairs 5' to the translation initiation codon. In the 3' flanking region, sequences homologous to glucocorticoid-response elements might be responsible for the increased expression of the ..beta../sub 2/AR gene observed after treatment of the transfected cells with hydrocortisone. In addition, 5' to the promoter region, an open reading frame encodes a 251-residue polypeptide that displays striking homologies with protein kinases and other nucleotide-binding proteins.

  9. Astrocytic β2 Adrenergic Receptor Gene Deletion Affects Memory in Aged Mice

    Science.gov (United States)

    Jensen, Cathy Joanna; Demol, Frauke; Bauwens, Romy; Kooijman, Ron; Massie, Ann; Villers, Agnès; Ris, Laurence; De Keyser, Jacques

    2016-01-01

    In vitro and in vivo studies suggest that the astrocytic adrenergic signalling enhances glycogenolysis which provides energy to be transported to nearby cells and in the form of lactate. This energy source is important for motor and cognitive functioning. While it is suspected that the β2-adrenergic receptor on astrocytes might contribute to this energy balance, it has not yet been shown conclusively in vivo. Inducible astrocyte specific β2-adrenergic receptor knock-out mice were generated by crossing homozygous β2-adrenergic receptor floxed mice (Adrb2flox) and mice with heterozygous tamoxifen-inducible Cre recombinase-expression driven by the astrocyte specific L-glutamate/L-aspartate transporter promoter (GLAST-CreERT2). Assessments using the modified SHIRPA (SmithKline/Harwell/Imperial College/Royal Hospital/Phenotype Assessment) test battery, swimming ability test, and accelerating rotarod test, performed at 1, 2 and 4 weeks, 6 and 12 months after tamoxifen (or vehicle) administration did not reveal any differences in physical health or motor functions between the knock-out mice and controls. However deficits were found in the cognitive ability of aged, but not young adult mice, reflected in impaired learning in the Morris Water Maze. Similarly, long-term potentiation (LTP) was impaired in hippocampal brain slices of aged knock-out mice maintained in low glucose media. Using microdialysis in cerebellar white matter we found no significant differences in extracellular lactate or glucose between the young adult knock-out mice and controls, although trends were detected. Our results suggest that β2-adrenergic receptor expression on astrocytes in mice may be important for maintaining cognitive health at advanced age, but is dispensable for motor function. PMID:27776147

  10. Polymorphisms in α- and β-Adrenergic Receptor Genes, Hypertension, and Obstructive Sleep Apnea: The Skaraborg Sleep Study

    Directory of Open Access Journals (Sweden)

    Kristina Bengtsson Boström

    2010-01-01

    Full Text Available The sympathetic nervous system and the adrenergic receptors play an important role in regulation of blood pressure. This study explored the associations between functional polymorphisms of the α2B-, β1-, and β2-adrenergic receptor genes and obstructive sleep apnea (OSA in hypertensive patients and hypertension in patients with OSA in a populationbased sample of 157 hypertensive patients and 181 healthy control subjects. Only the Arg389Gly polymorphism of the β1-adrenergic receptor gene was associated with increased risk for mild OSA in hypertensive patients (Arg/Arg versus Gly/Arg/Gly/Gly, 2.1, 95% CI, 1.02–4.7. Hypertensive men carrying the Arg389Arg genotype had higher crude and age-adjusted AHI than carriers of the Arg389Gly/Gly389Gly genotypes. When adjusted also for BMI this difference became borderline significant. This difference was not observed in women. The risk of hypertension in mild OSA was associated with increasing number of Arg-alleles (Arg/Arg OR 5.4, 95% CI 1.4–21.2.

  11. 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

  12. Beta 2-adrenergic receptor gene association with overweight and asthma in children and adolescents and its relationship with physical fitness

    Directory of Open Access Journals (Sweden)

    Neiva Leite

    2015-12-01

    Full Text Available Objective: To investigate the association of Arg16Gly and Gln27Glu polymorphisms of β2-adrenergic receptor gene (ADRB2 with the occurrence of asthma and overweight and the gene's influence on anthropometric, clinic, biochemical and physical fitness variables in children and adolescents. Methods: Subjects were evaluated for allelic frequencies of the β2-adrenergic receptor gene, height, weight, body mass index (BMI, BMI Z-score, waist circumference (WC, pubertal stage, resting heart rate (HRres, blood pressure (BP, total cholesterol (TC, glucose, insulin, high density lipoprotein (HDL-C, low density lipoprotein (LDL-C, triglyceride (TG, Homeostasis Metabolic Assessment (HOMA2-IR, Quantitative Insulin Sensitivity Check Index (QUICKI and maximal oxygen uptake (VO2max. The participants were divided in four groups: overweight asthmatic (n=39, overweight non-asthmatic (n=115, normal weight asthmatic (n=12, and normal weight non-asthmatic (n=40. Results: Regarding the Gln27Glu polymorphism, higher total cholesterol was observed in usual genotype individuals than in genetic variant carriers (p=0.04. No evidence was found that the evaluated polymorphisms are influencing the physical fitness. The Arg16 allele was found more frequently among the normal weight asthmatic group when compared to the normal weight non-asthmatic group (p=0.02, and the Glu27 allele was more frequently found in the overweight asthmatics group when compared to the normal weight non-asthmatic group (p=0.03. Conclusions: The association of Arg16 allele with the occurrence of asthma and of the Glu27 allele with overweight asthmatic adolescents evidenced the contribution of the β2-adrenergic receptor gene to the development of obesity and asthma.

  13. Adrenergic receptors are a fallible index of adrenergic denervation hypersensitivity

    DEFF Research Database (Denmark)

    Dejgaard, Anders; Liggett, S B; Christensen, N J

    1991-01-01

    by measuring these in a group of subjects with well-documented adrenergic denervation hypersensitivity, patients with diabetic autonomic neuropathy. Mononuclear leukocyte beta 2-adrenergic receptor densities (and binding affinities), measured with 125I-labelled pindolol, and isoproterenol-stimulated cyclic AMP...... accumulation, in samples from patients with insulin-dependent diabetes mellitus (IDDM) with diabetic autonomic neuropathy (n = 8), were no different from those in samples from patients with IDDM without neuropathy (n = 8), or from non-diabetic subjects (n = 8). In addition, platelet alpha 2-adrenergic receptor...... to diabetic autonomic neuropathy. Regardless of the mechanism of adrenergic denervation hypersensitivity in such patients, these data provide further evidence that measurements of cellular adrenergic receptors (and adenylate cyclase) in vitro are a fallible index of sensitivity to catecholamines in vivo....

  14. Gene transfer of a β2-adrenergic receptor kinase inhibitor up-regulates the level of β2-adrenergic receptor and cAMP in the asthmatic murine lung

    Institute of Scientific and Technical Information of China (English)

    Mao Huang; Yan Wu; Xin Yao; Wuangjian Cha; Kaisheng Yin

    2005-01-01

    Objective: To investigate the effects of gene transfer of a β-adrenergic receptor(β-AR) kinase inhibitor(β ARKct)on pulmonary β2-adrenergic receptor and cAMP following β2-AR agonist treatment in asthmatic mice, and to analyze the relationship between the routes of gene delivery and the changes of β2AR and cAMP. Methods: BALB/c mice were sensitized and challenged by ovalbumin to establish the asthmatic model treated with βAR agonist ( salbutamol injected intramuscularly). The plasmid with the expression of βARKct was constructed and βARKct gene transfer was performed through intravenous injection or intratracheal instillation in asthmatic mice.The gene expression was measured with Western blot analysis, and the changes of pulmonary β-AR and cAMP evaluated by Radioimmunoassay. Results: The expression of tranfered βARKct gene was detectable in lungs and it was expressed more in the lungs of the mice receiving intratracheally plasmid than those receiving intravenously. The levels of βAR and cAMP were upregulated after using plasmid-βARKct to the asthmatic mice treated with β AR agonist. Conclusion: Our results indicated that there were down-regulation of βAR and cAMP in asthmatic mice treated with βAR agonist. Gene transfer of βARKct could inhibit the extent of the down-regulation of βAR and cAMP. The route of gene delivery could also affect the degree of up-regulation of βAR and cAMP. Gene transfer βARKct may provide a novel approach to the therapeutic strategy for asthma.

  15. The Polymorphisms of Ser49Gly and Gly389Arg in Beta-1-Adrenergic Receptor Gene in Major Depression

    Science.gov (United States)

    KOKUT, Süleyman; ATAY, İnci Meltem; UZ, Efkan; AKPINAR, Abdullah; DEMİRDAŞ, Arif

    2015-01-01

    Introduction It was reported that the genetic susceptibility of major depressive disorder (MDD) is related with genetic polymorphisms. The aim of this study was to investigate the possible association of the genotype and allele frequencies of Ser49Gly and Arg389Gly polymorphisms in MDD by comparing them with healthy subjects. Methods A total of 144 patients with MDD diagnosed according to Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) criteria and 105 healthy controls were included in the study. Polymerase chain reaction (PCR) with restriction fragment length polymorphism (RFLP) was used for genotyping. Results Of the 144 participants in the MDD group, 77 (53.5%) had homozygous wild type (AA), 57 (39.6%) had heterozygous type (AG), and 10 (6.9%) had mutant (GG) genotype for Ser49Gly, whereas 75 (52.1%) had homozygous wild type (GG), 59 (41.0%) had heterozygous (GC) type, and 10 (6.9%) had mutant homozygous (CC) genotype for Gly386Arg. There were no significant difference in the allele and genotype frequencies of the beta-1-adrenergic receptor (ADRB1) gene for Ser49Gly and Arg389Gly polymorphisms after comparing with healthy controls (p=0.626; p=0.863 and p=0.625; p=0.914). Conclusion The results of our study did not reveal a major effect of the polymorphism of Ser49Gly and Gly389Arg in the ADRB1 gene in MDD. Further studies with larger sample size are required to elucidate the role of other beta-1 adrenergic gene polymorphisms in MDD.

  16. Circulating sex hormones and gene expression of subcutaneous adipose tissue oestrogen and alpha-adrenergic receptors in HIV-lipodystrophy: implications for fat distribution

    DEFF Research Database (Denmark)

    Andersen, Ove; Pedersen, Steen B; Svenstrup, Birgit;

    2007-01-01

    of alpha2A-adrenergic-receptor correlated positively with expression of oestrogen-receptor-alpha. CONCLUSIONS: The results fit the hypothesis that sex hormones play a role in altered fat distribution and insulin sensitivity of male patients with HIV-lipodystrophy. The effect of oestradiol......OBJECTIVE: Circulating oestradiol and testosterone, which have been shown to increase in human immunodeficiency virus (HIV)-infected patients following highly active antiretroviral therapy (HAART), may influence fat distribution and insulin sensitivity. Oestradiol increases subcutaneous adipose...... tissue in humans possibly through binding to oestrogen-receptor-alpha, which in turn activates anti-lipolytic alpha2A-adrenergic-receptor. DESIGN AND METHODS: To address these issues circulating pituitary-gonadal-axis hormones and gene expression of receptors in subcutaneous adipose tissue were...

  17. α1B-Adrenergic receptor signaling controls circadian expression of Tnfrsf11b by regulating clock genes in osteoblasts

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    Takao Hirai

    2015-11-01

    Full Text Available Circadian clocks are endogenous and biological oscillations that occur with a period of <24 h. In mammals, the central circadian pacemaker is localized in the suprachiasmatic nucleus (SCN and is linked to peripheral tissues through neural and hormonal signals. In the present study, we investigated the physiological function of the molecular clock on bone remodeling. The results of loss-of-function and gain-of-function experiments both indicated that the rhythmic expression of Tnfrsf11b, which encodes osteoprotegerin (OPG, was regulated by Bmal1 in MC3T3-E1 cells. We also showed that REV-ERBα negatively regulated Tnfrsf11b as well as Bmal1 in MC3T3-E1 cells. We systematically investigated the relationship between the sympathetic nervous system and the circadian clock in osteoblasts. The administration of phenylephrine, a nonspecific α1-adrenergic receptor (AR agonist, stimulated the expression of Tnfrsf11b, whereas the genetic ablation of α1B-AR signaling led to the alteration of Tnfrsf11b expression concomitant with Bmal1 and Per2 in bone. Thus, this study demonstrated that the circadian regulation of Tnfrsf11b was regulated by the clock genes encoding REV-ERBα (Nr1d1 and Bmal1 (Bmal1, also known as Arntl, which are components of the core loop of the circadian clock in osteoblasts.

  18. Beta adrenergic receptors in human cavernous tissue

    Energy Technology Data Exchange (ETDEWEB)

    Dhabuwala, C.B.; Ramakrishna, C.V.; Anderson, G.F.

    1985-04-01

    Beta adrenergic receptor binding was performed with /sup 125/I iodocyanopindolol on human cavernous tissue membrane fractions from normal tissue and transsexual procedures obtained postoperatively, as well as from postmortem sources. Isotherm binding studies on normal fresh tissues indicated that the receptor density was 9.1 fmoles/mg. with a KD of 23 pM. Tissue stored at room temperature for 4 to 6 hours, then at 4C in saline solution for 19 to 20 hours before freezing showed no significant changes in receptor density or affinity, and provided evidence for the stability of postmortem tissue obtained within the same time period. Beta receptor density of 2 cavernous preparations from transsexual procedures was not significantly different from normal control tissues, and showed that high concentrations of estrogen received by these patients had no effect on beta adrenergic receptor density. Displacement of /sup 125/iodocyanopindolol by 5 beta adrenergic agents demonstrated that 1-propranolol had the greatest affinity followed by ICI 118,551, zinterol, metoprolol and practolol. When the results of these displacement studies were subjected to Scatfit, non- linear regression line analysis, a single binding site was described. Based on the relative potency of the selective beta adrenergic agents it appears that these receptors were of the beta 2 subtype.

  19. Differential coupling of Arg- and Gly389 polymorphic forms of the β1-adrenergic receptor leads to pathogenic cardiac gene regulatory programs

    OpenAIRE

    2008-01-01

    The β1-adrenergic receptor (β1AR; ADRB1) polymorphism Arg389Gly is located in an intracellular loop and is associated with distinct human and mouse cardiovascular phenotypes. To test the hypothesis that β1-Arg389 and β1-Gly389 alleles could differentially couple to pathways beyond that of classic Gs-adenylyl cyclase (AC)/cAMP signaling, we performed comparative gene expression profile analyses on hearts from wild-type and transgenic mice that expressed either human β1-Arg389 or β1-Gly389 rece...

  20. Circulating sex hormones and gene expression of subcutaneous adipose tissue oestrogen and alpha-adrenergic receptors in HIV-lipodystrophy: implications for fat distribution

    DEFF Research Database (Denmark)

    Andersen, Ove; Pedersen, Steen B; Svenstrup, Birgit

    2007-01-01

    OBJECTIVE: Circulating oestradiol and testosterone, which have been shown to increase in human immunodeficiency virus (HIV)-infected patients following highly active antiretroviral therapy (HAART), may influence fat distribution and insulin sensitivity. Oestradiol increases subcutaneous adipose...... tissue in humans possibly through binding to oestrogen-receptor-alpha, which in turn activates anti-lipolytic alpha2A-adrenergic-receptor. DESIGN AND METHODS: To address these issues circulating pituitary-gonadal-axis hormones and gene expression of receptors in subcutaneous adipose tissue were...... determined in 31 nondiabetic HIV-infected male patients receiving HAART (16 with lipodystrophy), in whom measures of fat distribution (CT and DEXA-scans) and insulin sensitivity (hyperinsulinaemic euglycaemic clamp) were available. RESULTS: Total and free oestradiol and testosterone were decreased...

  1. Thyroid hormone and adrenergic signaling interact to control pineal expression of the dopamine receptor D4 gene (Drd4)

    DEFF Research Database (Denmark)

    Kim, Jong-So; Bailey, Michael J; Weller, Joan L;

    2009-01-01

    . Our studies indicate that Drd4 is the dominant dopamine receptor gene expressed in the pineal gland. The gene is expressed in pinealocytes at levels which are approximately 100-fold greater than in other tissues, except the retina, in which transcript levels are similar. Pineal Drd4 expression...... and whether thyroid hormone controls expression of other genes in the pineal gland.......Dopamine plays diverse and important roles in vertebrate biology, impacting behavior and physiology through actions mediated by specific G-protein-coupled receptors, one of which is the dopamine receptor D4 (Drd4). Here we present studies on the >100-fold daily rhythm in rat pineal Drd4 expression...

  2. Adrenergic Receptors From Molecular Structure to in vivo function.

    Science.gov (United States)

    Hein, L; Kobilka, B K

    1997-07-01

    Adrenergic receptors form the interface between the sympathetic nervous system and the cardiovascular system as well as many endocrine and parenchymal tissues. Although several hundred G-protein-coupled receptors have been identified, adrenergic receptors, along with the visual pigment rhodopsin, have been among the most extensively studied members of this family of receptors. This review focuses on recent advances in understanding the molecular structure, function, and regulation of adrenergic receptors using in vitro systems and integrates recent transgenic animal models that were generated to study the adrenergic system in vivo. (Trends Cardiovasc Med 1997;7:137-145). © 1997, Elsevier Science Inc.

  3. Energy expenditure, body composition and insulin response to glucose in male twins discordant for the Trp64Arg polymorphism of the beta3-adrenergic receptor gene

    DEFF Research Database (Denmark)

    Højlund, K; Christiansen, C; Bjørnsbo, K S;

    2006-01-01

    and environmental background, the Trp64Arg polymorphism of the beta3AR gene is associated with lower fat mass, fasting insulin levels and an appropriate insulin response to glucose. Thus, heterozygosity for the Trp64Arg variant is unlikely to increase the risk of obesity, insulin resistance or type 2 diabetes.......AIM: The tryptophan to arginine change in position 64 (Trp64Arg) polymorphism of the beta3-adrenergic receptor (beta3AR) gene has been associated with an increased prevalence of obesity, insulin resistance and type 2 diabetes. In this, decreased rates of energy expenditure and impaired insulin......-ray absorptiometry scanning and energy expenditure by indirect and direct calorimetry. RESULTS: Twins heterozygous for the Trp64Arg polymorphism showed significantly lower fat mass independent of the method used, and significantly lower fasting insulin and glucose concentrations compared with their homozygous wild...

  4. The β3-adrenergic receptor is dispensable for browning of adipose tissues.

    Science.gov (United States)

    de Jong, Jasper M A; Wouters, René T F; Boulet, Nathalie; Cannon, Barbara; Nedergaard, Jan; Petrovic, Natasa

    2017-02-21

    Brown and brite/beige adipocytes are attractive therapeutic targets to treat metabolic diseases. To maximally utilize their functional potential, further understanding is required about their identities and their functional differences. Recent studies with β3-adrenergic receptor knockout mice reported that brite/beige adipocytes, but not classical brown adipocytes, require the β3-adrenergic receptor for cold-induced transcriptional activation of thermogenic genes. We aimed to further characterize this requirement of the β3-adrenergic receptor as a functional distinction between classical brown and brite/beige adipocytes. However, when comparing wild-type and β3-adrenergic receptor knockout mice, we observed no differences in cold-induced thermogenic gene expression (Ucp1, Pgc1a, Dio2 and Cidea) in brown or white (brite/beige) adipose tissues. Irrespective of the duration of the cold exposure or the sex of the mice, we observed no effect of the absence of the β3-adrenergic receptor. Experiments with the β3-adrenergic receptor agonist CL-316,243 verified the functional absence of β3-adrenergic signaling in these knockout mice. The β3-adrenergic receptor knockout model in the present study was maintained on a FVB/N background, whereas earlier reports used C57BL/6 and 129Sv mice. Thus, our data imply background-dependent differences in adrenergic signaling mechanisms in response to cold exposure. Nonetheless, the present data indicate that the β3-adrenergic receptor is dispensable for cold-induced transcriptional activation in both classical brown and, as opposed to earlier studies, brite/beige cells. This should be taken into account in the increasing number of studies on the induction of browning and their extrapolation to human physiology.

  5. Association of Gln27Glu and Arg16Gly polymorphisms in Beta2-adrenergic receptor gene with obesity susceptibility: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Hongxiu Zhang

    Full Text Available BACKGROUND: The beta2-adrenergic receptor (ADRB2 gene polymorphism has been implicated in susceptibility to obesity, but study results are still controversial. OBJECTIVE: The present meta-analysis is performed to determine whether there are any associations between the Gln27Glu (rs1042714 or the Arg16Gly (rs1042713 polymorphisms in ADRB2 and obesity susceptibility. METHODS: The PubMed (1950-2014, Embase (1974-2014, and China National Knowledge Infrastructure (CNKI, 1994-2014 databases were searched using the search terms ("Beta2-adrenergic receptor", "β2-adrenergic receptor" or "ADRB2", "polymorphism," and "obesity". Fixed- or random-effects pooled measures were determined on the bias of heterogeneity tests across studies. Publication bias was examined by Egger's test and the modified Begg's test. RESULTS: Eighteen published articles were selected for meta-analysis. Overall analyses showed that rs1042714 (Gln27Glu was associated with significantly increased obesity risk in the heterozygote model (Gln/Glu vs. Gln/Gln: OR: 1.16, 95% CI: 1.04-1.30, I2 = 49%, P = 0.009 and the dominant model (Gln/Glu + Glu/Glu vs. Gln/Gln: OR: 1.2, 95% CI: 1.00-1.44, I2 = 55%, P = 0.04, whereas no significant association was found in the other models for rs1042714. Also, no significant association was found between the rs1042713 (Arg16Gly gene polymorphism and the risk of obesity in all genetic models. In addition, neither rs1042713 (Arg16Gly nor rs1042714 (Gln27Glu showed any significant association with obesity susceptibility when the population were stratified based on gender. CONCLUSION: Our meta-analysis revealed that the rs1042714 (Gln27Glu polymorphism is associated with obesity susceptibility. However, our results do not support an association between rs1042713 (Arg16Gly polymorphisms and obesity in the populations investigated. This conclusion warrants confirmation by more case-control and cohort studies.

  6. Muscle Plasticity and β2-Adrenergic Receptors: Adaptive Responses of β2-Adrenergic Receptor Expression to Muscle Hypertrophy and Atrophy

    Directory of Open Access Journals (Sweden)

    Shogo Sato

    2011-01-01

    Full Text Available We discuss the functional roles of β2-adrenergic receptors in skeletal muscle hypertrophy and atrophy as well as the adaptive responses of β2-adrenergic receptor expression to anabolic and catabolic conditions. β2-Adrenergic receptor stimulation using anabolic drugs increases muscle mass by promoting muscle protein synthesis and/or attenuating protein degradation. These effects are prevented by the downregulation of the receptor. Endurance training improves oxidative performance partly by increasing β2-adrenergic receptor density in exercise-recruited slow-twitch muscles. However, excessive stimulation of β2-adrenergic receptors negates their beneficial effects. Although the preventive effects of β2-adrenergic receptor stimulation on atrophy induced by muscle disuse and catabolic hormones or drugs are observed, these catabolic conditions decrease β2-adrenergic receptor expression in slow-twitch muscles. These findings present evidence against the use of β2-adrenergic agonists in therapy for muscle wasting and weakness. Thus, β2-adrenergic receptors in the skeletal muscles play an important physiological role in the regulation of protein and energy balance.

  7. G16R single nucleotide polymorphism but not haplotypes of the ß2-adrenergic receptor gene alters cardiac output in humans

    DEFF Research Database (Denmark)

    Rokamp, Kim Z; Staalsø, Jonatan M; Gartmann, Martin

    2013-01-01

    Variation in genes encoding the ß2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) may influence Q¿ (cardiac output). The 46G>A (G16R) SNP (single nucleotide polymorphism) has been associated with ß2-mediated vasodilation, but the effect of ADRB2 haplotypes on Q¿ has not been...... studied. Five SNPs within ADRB2 (46G>A, 79C>G, 491C>T, 523C>A and 1053G>C by a pairwise tagging principle) and the I/D (insertion/deletion) polymorphism in ACE were genotyped in 143 subjects. Cardiovascular variables were evaluated by the Model flow method at rest and during incremental cycling exercise...

  8. Neurohumoral activation in heart failure: the role of adrenergic receptors

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    Patricia C. Brum

    2006-09-01

    Full Text Available Heart failure (HF is a common endpoint for many forms of cardiovascular disease and a significant cause of morbidity and mortality. The development of end-stage HF often involves an initial insult to the myocardium that reduces cardiac output and leads to a compensatory increase in sympathetic nervous system activity. Acutely, the sympathetic hyperactivity through the activation of beta-adrenergic receptors increases heart rate and cardiac contractility, which compensate for decreased cardiac output. However, chronic exposure of the heart to elevated levels of catecholamines released from sympathetic nerve terminals and the adrenal gland may lead to further pathologic changes in the heart, resulting in continued elevation of sympathetic tone and a progressive deterioration in cardiac function. On a molecular level, altered beta-adrenergic receptor signaling plays a pivotal role in the genesis and progression of HF. beta-adrenergic receptor number and function are decreased, and downstream mechanisms are altered. In this review we will present an overview of the normal beta-adrenergic receptor pathway in the heart and the consequences of sustained adrenergic activation in HF. The myopathic potential of individual components of the adrenergic signaling will be discussed through the results of research performed in genetic modified animals. Finally, we will discuss the potential clinical impact of beta-adrenergic receptor gene polymorphisms for better understanding the progression of HF.A insuficiência cardíaca (IC é a via final comum da maioria das doenças cardiovasculares e uma das maiores causas de morbi-mortalidade. O desenvolvimento do estágio final da IC freqüentemente envolve um insulto inicial do miocárdio, reduzindo o débito cardíaco e levando ao aumento compensatório da atividade do sistema nervoso simpático (SNS. Existem evidências de que apesar da exposição aguda ser benéfica, exposições crônicas a elevadas concentra

  9. Beta-Adrenergic gene therapy for cardiovascular disease

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    Koch Walter J

    2000-10-01

    Full Text Available Abstract Gene therapy using in vivo recombinant adenovirus-mediated gene transfer is an effective technique that offers great potential to improve existing drug treatments for the complex cardiovascular diseases of heart failure and vascular smooth muscle intimal hyperplasia. Cardiac-specific adenovirus-mediated transfer of the carboxyl-terminus of the β-adrenergic receptor kinase (βARKct, acting as a Gβγ-β-adrenergic receptor kinase (βARK1 inhibitor, improves basal and agonist-induced cardiac performance in both normal and failing rabbit hearts. In addition, βARKct adenovirus infection of vascular smooth muscle is capable of significantly diminishing neointimal proliferation after angioplasty. Therefore, further investigation is warranted to determine whether inhibition of βARK1 activity and sequestration of Gβγ via an adenovirus that encodes the βARKct transgene might be a useful clinical tool for the treatment of cardiovascular pathologies.

  10. 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...

  11. 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

  12. Effects of β2-Adrenergic Receptor Gene Polymorphisms on Ritodrine Therapy in Pregnant Women with Preterm Labor: Prospective Follow-Up Study

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    Jin Young Park

    2014-07-01

    Full Text Available This study aimed to evaluate the effects of β2-adrenergic receptor (ADRB2 gene polymorphisms on ritodrine therapy outcomes in patients with preterm labor. Genotyping analysis of ADRB2 gene (rs1042713, rs1042714, rs1042717, rs1042718, and rs1042719 was performed on 137 patients with preterm labor. Survival analysis was conducted for the effects of SNPs on the median time to delivery as a primary outcome. The median time to delivery in the study patients was 349.3 h. Gestational age at admission and modified Bishop scores revealed significant effects on time to delivery (p < 0.001. Among studied SNPs, rs1042717 and rs1042718 showed linkage disequilibrium in this population, and their effects on time to delivery were marginally significant (p < 0.1. Patients with variant-homozygotes in the rs1042713 showed considerably shortened time to delivery compared to wild-allele carriers. The rs1042719 polymorphism significantly affected time to delivery in both univariate and multivariate analysis; the GC and CC carriers showed 64% decrease in time to delivery compared to the wild-type homozygote carriers. Based on the results, it was concluded that the gene polymorphisms of ADRB2 could affect ritodrine therapy in patients with preterm labor. However, given the single-center and the relatively small sample size, our hypothesis requires further independent validation using multi-center and large sample size.

  13. Pharmacologic specificity of alpha-2 adrenergic receptor subtypes

    Energy Technology Data Exchange (ETDEWEB)

    Petrash, A.; Bylund, D.

    1986-03-01

    The authors have defined alpha-2 adrenergic receptor subtypes in human and rat tissues using prazosin as a subtype selective drug. Prazosin has a lower affinity (250 nM) at alpha-2A receptor and a higher affinity (5 nM) at alpha-2B receptors. In order to determine if other adrenergic drugs are selective for one or the other subtypes, the authors performed (/sup 3/H)yohimbine inhibition experiments with various adrenergic drugs in tissues containing alpha-2A, alpha-2B or both subtypes. Oxymetazoline, WB4101 and yohimbine were found to be 80-, 20- and 10-fold more potent at alpha-2A receptors than at alpha-2B receptors. Phentolamine, adazoxan, (+)- and (-)-mianserin, clonidine, (+)-butaclamol, (-)- and (+)-norepinephrine, epinephrine, dopamine and thioridazine were found to have equal affinities for the two subtypes. These results further validate the subdivision of alpha-2 adrenergic receptors into alpha-2A and alpha-2B subtypes.

  14. The Effects of Continuous and Intermittent Feeding of β-agonist Zilpaterol Hydrochloride on Muscle β-adrenergic Receptors Gene Expression in Feedlot Male Lambs

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    Vahid Vahedi

    2016-04-01

    Full Text Available Introduction The compounds known as β-adrenergic agonists (β-AA are organic molecules that have the ability to bind to β-adrenergic receptors (β-AR and start biochemical reactions that will result in increase of accretion of skeletal muscle and reduction in accretion of fat. The anabolic responses to β-AA are temporary, with a peak time occurring during the first 14 days, after which there is a linear decline in growth response, due to either down-regulation or desensitization of the β-AR. Based on down-regulation of β-AR research, the hypothesis that intermittent feeding of β-AA could enhance response on growth performance was created. The objective of this study was therefore to ascertain the effects of continuous and intermittent use of ZH for a period of 42 d on β-AR gene expression in Lori-Bakhtiari feedlot lambs. Materials and Methods The continuous feeding of ZH (daily regimen, intermittent 1 d feeding ZH followed by 1 d of withdrawal (1 on 1 off regimen, and intermittent 2 d feeding ZH followed by 2 d of withdrawal (2 on 2 off regimen were employed as the different feeding methods. Thirty two Lori-Bakhtiari male lambs (initial BW=44±4.7 kg were assigned to one of four treatments (8 lambs/treatment based on initial BW and were fed with a diet content of 14% protein and supplemented with 0.2 mg/kg of live weight d-1ZH. The basal diet without ZH was the added control group. For evaluating gene expression, biopsy samples of the semimembranosus muscle were collected from 3 lambs per treatment before ZH supplementation on d 0, and subsequently at d 21, and d 42. Samples were rapidly frozen in liquid N2. In laboratory after total RNA isolation from muscle, the RNA was then reverse-transcribed into complementary DNA (cDNA. Real time PCR for cDNA samples was performed using an iQ5 BioRad instrument. Results and Discussion The results of this study showed that the main effects and period × regimen interactions effect was not significant

  15. Human-specific SNP in obesity genes, adrenergic receptor beta2 (ADRB2, Beta3 (ADRB3, and PPAR γ2 (PPARG, during primate evolution.

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    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.

  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. Association of β-adrenergic receptor genes polymorphisms with incidence of subsequent cardiovascular events in Han Chinese patients with coronary artery disease

    Institute of Scientific and Technical Information of China (English)

    LI Zhi-gen; WU Hong; ZHOU Ying-ling; CHEN Zhu-jun; MENG Jin-xiu; YANG Jun-qing; CHEN Ji-yan

    2013-01-01

    Background Sequence variants in the β-adrenergic receptor (ADRB) genes have a close relationship with the development of coronary artery disease (CAD) and the patient's prognosis.However,there is a lack of data on the role of the variants in ADRBs genes in Han Chinese patients with CAD.We aimed to investigate the association of genetic variants in the ADRB1 and ADRB2 genes with the incidence of major adverse cardiac event (MACE) in Han Chinese patients with CAD.Methods A total of 545 Han Chinese patients with CAD undergoing percutaneous coronary intervention (PCI) were recruited to the study and followed for one year.Three variant sites in ADRB1 (rs1801253) and ADRB2 (rs1042713 and rs1042714) were genotyped.The effect of the ADRB1 and ADRB2 genotypes on MACE within one year was assessed.Results There were 47 cases of MACE during follow-up.There was no significant difference in the incidence of MACE among patients carrying different genotypes of the three variants in ADRB1 and ADRB2 (Log-rank,all P >0.05).Cox regression analysis showed no association between three variants in ADRB1 and ADRB2 genes and the incidence of MACE during one-year follow-up,the adjusted hazard ratios (95% confidence interval) for rs1801253,rs1042713 and rs1042714 were 1.05 (0.54-2.02),1.24 (0.58-2.64) and 1.66 (0.81-3.42),respectively.Conclusion Our data did not support a relationship between the three polymorphisms of ADRB1 (rs1801253) and ADRB2 (rs1042713 and rs1042714) genes and risk of subsequent cardiovascular events after PCI in Han Chinese patients with CAD.

  18. β3-adrenergic receptor gene, body mass index, bone mineral density and fracture risk in elderly men and women: the Dubbo Osteoporosis Epidemiology Study (DOES

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    Center Jacqueline R

    2006-07-01

    Full Text Available Abstract Background Recent studies have suggested that the Arg allele of β3-adrenergic receptor (ADRB3 gene is associated with body mass index (BMI, which is an important predictor of bone mineral density (BMD and fracture risk. However, whether the ADRB3 gene polymorphism is associated with fracture risk has not been investigated. The aim of study was to examine the inter-relationships between ADRB3 gene polymorphisms, BMI, BMD and fracture risk in elderly Caucasians. Methods Genotypes of the ADRB3 gene were determined in 265 men and 446 women aged 60+ in 1989 at entry into the study, whose BMD were measured by DXA (GE Lunar, WI USA at baseline. During the follow-up period (between 1989 and 2004, fractures were ascertained by reviewing radiography reports and personal interviews. Results The allelic frequencies of the Trp and the Arg alleles were 0.925 and 0.075 respectively, and the relative frequencies of genotypes Trp/Trp, Trp/Arg and Arg/Arg 0.857, 0.138 and 0.006 respectively. There was no significant association between BMI and ADRB3 genotypes (p = 0.10 in women and p = 0.68 in men. There was also no significant association between ADRB3 genotypes and lumbar spine or femoral neck BMD in either men and women. Furthermore, there were no significant association between ADRB3 genotypes and fracture risk in both women and men, either before or after adjusting for and, BMD and BMI. Conclusion The present data suggested that in Caucasian population the contribution of ADRB3 genotypes to the prediction of BMI, BMD and fracture risk is limited.

  19. The Relationship between Birthweight and Longitudinal Changes of Blood Pressure Is Modulated by Beta-Adrenergic Receptor Genes: The Bogalusa Heart Study

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    Wei Chen

    2010-01-01

    Full Text Available This study examines the genetic influence of β-adrenergic receptor gene polymorphisms (β2-AR Arg16Gly and β3-AR Trp64Arg on the relationship of birthweight to longitudinal changes of blood pressure (BP from childhood to adulthood in 224 black and 515 white adults, aged 21–47 years, enrolled in the Bogalusa Heart Study. Blacks showed significantly lower birthweight and frequencies of β2-AR Gly16 and β3-AR Trp64 alleles and higher BP levels and age-related trends than whites. In multivariable regression analyses using race-adjusted BP and birthweight, low birthweight was associated with greater increase in age-related trend of systolic BP (standardized regression coefficient β=−0.09, P=.002 and diastolic BP (β=−0.07, P=.037 in the combined sample of blacks and whites, adjusting for the first BP measurement in childhood, sex, age, and gestational age. Adjustment for the current body mass index strengthened the birthweight-BP association. Importantly, the strength of the association, measured as regression coefficients, was modulated by the combination of β2-AR and β3-AR genotypes for systolic (P=.042 for interaction and diastolic BP age-related trend (P=.039 for interaction, with blacks and whites showing a similar trend in the interaction. These findings indicate that the intrauterine programming of BP regulation later in life depends on β-AR genotypes.

  20. Adrenergic receptor control mechanism for growth hormone secretion.

    Science.gov (United States)

    Blackard, W G; Heidingsfelder, S A

    1968-06-01

    The influence of catecholamines on growth hormone secretion has been difficult to establish previously, possibly because of the suppressive effect of the induced hyperglycemia on growth hormone concentrations. In this study, an adrenergic receptor control mechanism for human growth hormone (HGH) secretion was uncovered by studying the effects of alpha and beta receptor blockade on insulin-induced growth hormone elevations in volunteer subjects. Alpha adrenergic blockade with phentolamine during insulin hypoglycemia, 0.1 U/kg, inhibited growth hormon elevations to 30-50% of values in the same subjects during insulin hypoglycemia without adrenergic blockade. More complete inhibition by phentolamine could not be demonstrated at a lower dose of insulin (0.05 U/kg). Beta adrenergic blockade with propranolol during insulin hypoglycemia significantly enhanced HGH concentrations in paired experiments. The inhibiting effect of alpha adrenergic receptor blockade on HGH concentrations could not be attributed to differences in blood glucose or free fatty acid values; however, more prolonged hypoglycemia and lower plasma free fatty acid values may have been a factor in the greater HGH concentrations observed during beta blockade. In the absence of insulin induced hypoglycemia, neither alpha nor beta adrenergic receptor blockade had a detectable effect on HGH concentrations. Theophylline, an inhibitor of cyclic 3'5'-AMP phosphodiesterase activity, also failed to alter plasma HGH concentrations. These studies demonstrate a stimulatory effect of alpha receptors and a possible inhibitory effect of beta receptors on growth hormone secretion.

  1. THE POLYMORPHISM OF Α2B-ADRENERGIC RECEPTOR GENE — A NEW GENETIC MARKER OF THE HEREDITARY SICK SINUS SYNDROME

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    S. Iu. Nikulina

    2010-01-01

    Full Text Available Aim. To study the association of the hereditary sick sinus syndrome (SSS with gene α2B-adrenergic receptor (ADRA2B polymorphism.Material and methods. 29 families with hereditary primary SSS from the database of the Chair of Therapy № 1 of Krasnoyarsk State Medical University named after prof. V.F. Voyno-Yasenetsky were included in the study. Group 1 included probands (20 women and 9 men, 58±0.15 y.o., group 2 – proband relatives of I, II and III degree (65 males and 68 females, 39±0.13 y.o., group 3 (control — 89 healthy volunteers. Clinical examination (physical examination, ECG, bicycle ergometry, ECG monitoring, atropine test, electrophysiological study, echocardiography was performed in all probands and their relatives. The diagnosis of SSS was confirmed by transesophageal left atrium stimulation in 75 individuals. Genotypic examination of gene ADRA2B I/D polymorphism was performed in 213 individuals: 75 SSS-patients, 49 their healthy relatives, 89 healthy volunteers.Results. 3 types of ADRA2B genotypes (II — homozygous wild, ID — heterozygous, DD — homozygous mutant were founded by allele-specific polymerase chain reaction. Significant prevalence of the homozygous genotype of more rare alleles DD in SSS-patients (28±5.2% compared to the control group (8.99±3.0% was found.Conclusion. Study of the genetic marker can be used to identify predisposition to hereditary SSS in the population and individual-family level. SSS due to mutations in genes that regulate cell function of sinus node and the sinoatrial conduct occurs, apparently, extremely rarely.

  2. The acute modulation of norepinephrine on immune responses and genes expressions via adrenergic receptors in the giant freshwater prawn, Macrobrachium rosenbergii.

    Science.gov (United States)

    Chang, Chin-Chyuan; Tsai, Wan-Lin; Jiang, Jia-Rong; Cheng, Winton

    2015-10-01

    Norepinephrine (NE), immunocompetent parameters (total haemocyte count (THC), phenoloxidase (PO) activity, respiratory burst (RB), superoxide dismutase (SOD) activity, phagocytic activity and clearance efficiency to Lactococcus garvieae), and prophenoloxidase (proPO) system-related genes (lipopolysaccharide- and β-1,3-glucan-binding protein, LGBP; prophenoloxidase, proPO; peroxinectin, PE; α2-macroglobulin, α2-M) expressions were investigated in Macrobrachium rosenbergii received NE through injection at 50 pmol/prawn after 0, 30, 60, and 120 min. Furthermore, the PO activity, RB, SOD activity, phagocytic activity and proPO system-related genes expressions were determined in haemocytes incubated with cacodylate buffer (CAC), NE, and NE co-treated with various adrenergic receptor (AR) antagonists in vitro. Results showed that NE, THC, granular cells, PO activity, SOD activity, proPO system-related genes expressions, and phagocytic activity and clearance efficiency to L. garvieae increased; PO activity per granulocyte and RB per haemocyte decreased from 30 to 120 min; semigranular cells and RB increased in the initial 30 min, and then decreased at 120 min when the prawns received NE by injection. In vitro studies, all the determined immune parameters and genes expressions were significantly decreased in haemocytes incubated with NE after 30 min. The negative effects of NE were prevented on the PO activity and phagocytic activity by the β-AR antagonist of metoprolol (Met), on the SOD activity by the β-AR antagonist of propranolol (Pro), on the RB by the β-AR antagonist of Met and prazosin (Pra), and on the proPO system-related genes expressions by α-AR antagonist of Pra. These results show that NE modulates prawn haemocytes proPO system-related genes expressions via α1-AR, PO activity and phagocytosis via β1-AR, respiratory burst via α1-and β1-ARs, and SOD activity via β2-AR. It is concluded that NE stimulates the regulation of immunocompetence parameters

  3. AT(1) receptor Gαq protein-independent signalling transcriptionally activates only a few genes directly, but robustly potentiates gene regulation from the β2-adrenergic receptor

    DEFF Research Database (Denmark)

    Christensen, Gitte Lund; Knudsen, Steen; Schneider, Mikael;

    2011-01-01

    of Gαq protein-dependent and -independent regulation of AT(1)R mediated gene expression. We found angiotensin II to regulate 212 genes, whereas Gαq-independent signalling obtained with the biased agonist, SII angiotensin II only regulated few genes. Interestingly, SII angiotensin II, like Ang II vastly...

  4. Relationship between Trp64Arg mutation in the β3-adrenergic receptor gene and metabolic syndrome: a seven-year follow-up study

    Institute of Scientific and Technical Information of China (English)

    ZHU Lü-yun; HU Li-ye; LI Xiao-ling; WANG Guang-yu; SHAN Wei; MA Li-cheng; WANG Xiu-hui

    2010-01-01

    Background It has been shown that the β3-adrenergic receptor (β3-AR) gene Trp64Arg mutation was closely related to obesity and insulin resistance, and may be related to the prevalence of metabolic syndrome (MS). The aim of this study was to investigate the relationship between the 33-AR gene mutation and the prevalence of MS. Methods A seven-year follow-up study was initiated in 2000, with 496 samples of simplex obese subjects (body mass index ≥25 kg/m2) and 248 normal-weight subjects. According to the β3-AR genotypes, the subjects were classified as Trp64 homozygote group and Arg64 carrier group and after 7 years the prevalence of MS was determined. Results According to the baseline profile, there were no significant differences in the adiposity, blood pressure, lipid profile, fasting plasma glucose and fasting insulin between Trp64 homozygote group and Arg64 carrier group either in obesity or normal-weight subjects. The results of follow-up study indicated that in obese men the prevalence rate of MS was much higher in Arg64 carrier group than that in Trp64 homozygote group (54.76% vs. 40.85%, P <0.05), but there was no statistical difference in women of the above groups. The prevalence rate of MS in obese men of both Trp64 homozygote group and Arg64 carrier obese group were obviously higher than that in women of the above groups (40.85% vs. 18.27% and 54.76% vs 21.28%, all P <0.005). Differences were not statistically significant in the prevalence of MS for normal weight Trp64 homozygote group and normal weight Arg64 carrier group, either between men, between women, or between men and women. Comparison of populations indicated that no matter with the β3-AR gene mutation or not, the prevalence of MS in obese subjects was significantly higher than normal weight subjects (X2=28.240 and x2=15.586, all P <0.005). Logistic analysis showed that the mutation of β3-AR gene was associated with the prevalence of MS in men.

  5. The Gln27Glu Polymorphism in β2-Adrenergic receptor gene is linked to hypertriglyceridemia, hyperinsulinemia and hyperleptinemia in Saudis

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    Daghestani Maha H

    2010-08-01

    Full Text Available Abstract Background β2-adrenoceptor (β2AR gene polymorphism glutamine 27 glutamic acid (Gln27Glu and Arg16Gly were reported to have an association with obesity and obesity related disorders in some population. We evaluated Gln27Glu polymorphism in the β2AR gene in obese Saudi populations to investigate the association of β2AR gene with obesity and other related metabolic parameters. Design We studied possible association of Gln27Glu in β2AR gene with body mass index (BMI, anthropometric measurements and other metabolic parameters. The β2AR gene polymorphism (Gln27Glu was identified by sequencing PCR products representing locus of interest. Based on BMI, the subjects were divided into three groups, normal weight, overweight and obese. The genotype and allele frequency were calculated separately for each group. Results The allelic frequency of Glu27 did not differ amongst the three groups, though the Glu27 homozygote (Glu/Glu were more in obese subjects and had higher concentration of triglyceride, leptin and insulin compared to in the Gln27 heterozygotes and Gln/Gln homozygotes. Conclusions In this study we were able to provide evidence on the influence of Gln27Glu genetic variant of β2AR gene on lipid phenotypes, insulin and leptin levels in the Saudi populations.

  6. Association of β1 and β3 adrenergic receptors gene polymorphisms with insulin resistance and high lipid profiles related to type 2 diabetes and metabolic syndrome

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    Ana I. Burguete-García

    2014-06-01

    Full Text Available Background: Among the diverse genes associated to type 2 diabetes (T2D, the β-adrenergic receptors are an excellent candidate to study in Mexican population. The objective of this work was to analyze the association of polymorphisms in ADRB1 (rs1801253 (Arg389Gly and ADRB3 (Trp64Arg genes with T2D and metabolic syndrome (MS. Methods: We studied 445 MS patients, 502 with T2D and 552 healthy controls. Anthropometric features and complete biochemical profile were evaluated, and Arg389Gly and Trp64Arg SNPs were determined by TaqMan assays. Data analysis was adjusted by African, Caucasian and Amerindian ancestral percentage. Results: The variant Arg389Gly of ADRB1 was statistically associated with an increase of LDL levels (P < 0.008, and the variant ADRB3 Trp64Arg was associated to larger HOMA-IR (P < 0.018 and with an increase of insulin levels (P < 0.001. A multiple logistic regression analysis was made in three grouping models: For ADRB3 in the codominant model Trp/Arg genotype, there was an OR of 1.53 (1.09-2.13, P < 0.003 which was increased up to OR 2.99 (1.44-6.22, P < 0.003 for the Arg/Arg genotype. Similar risk association was found under the dominant model Trp/Arg-Arg/Arg genotype with OR 1.67 (1.21-2.30; P < 0.002. In the recessive model (Arg/Arg genotype, there was also a high association OR 2.56 (1.24-5.26, P < 0.01. Conclusions: The ADRB3 Trp64Arg variant is a susceptibility gene polymorphism for T2D and the ADRB1 Gly389Arg for lipid metabolism disruption. These results show that these variants are potential biomarkers for predicting metabolic alterations and evolution in diabetic and metabolic syndrome patients.

  7. 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.

  8. β-Adrenergic receptor signaling and modulation of long-term potentiation in the mammalian hippocampus.

    Science.gov (United States)

    O'Dell, Thomas J; Connor, Steven A; Guglietta, Ryan; Nguyen, Peter V

    2015-09-01

    Encoding new information in the brain requires changes in synaptic strength. Neuromodulatory transmitters can facilitate synaptic plasticity by modifying the actions and expression of specific signaling cascades, transmitter receptors and their associated signaling complexes, genes, and effector proteins. One critical neuromodulator in the mammalian brain is norepinephrine (NE), which regulates multiple brain functions such as attention, perception, arousal, sleep, learning, and memory. The mammalian hippocampus receives noradrenergic innervation and hippocampal neurons express β-adrenergic receptors, which are known to play important roles in gating the induction of long-lasting forms of synaptic potentiation. These forms of long-term potentiation (LTP) are believed to importantly contribute to long-term storage of spatial and contextual memories in the brain. In this review, we highlight the contributions of noradrenergic signaling in general and β-adrenergic receptors in particular, toward modulating hippocampal LTP. We focus on the roles of NE and β-adrenergic receptors in altering the efficacies of specific signaling molecules such as NMDA and AMPA receptors, protein phosphatases, and translation initiation factors. Also, the roles of β-adrenergic receptors in regulating synaptic "tagging" and "capture" of LTP within synaptic networks of the hippocampus are reviewed. Understanding the molecular and cellular bases of noradrenergic signaling will enrich our grasp of how the brain makes new, enduring memories, and may shed light on credible strategies for improving mental health through treatment of specific disorders linked to perturbed memory processing and dysfunctional noradrenergic synaptic transmission.

  9. Adrenergic Receptors and Metabolism: Role in development of cardiovascular disease

    Directory of Open Access Journals (Sweden)

    Michele eCiccarelli

    2013-10-01

    Full Text Available Activation of the adrenergic system has a profound effects on metabolism. Increased circulating catecholamine and activation of the different adrenergic receptors deployed in the various organs produce important metabolic responses which include: 1 increased lipolysis and elevated levels of fatty acids in plasma, 2 increased gluconeogenesis by the liver to provide substrate for the brain and 3 moderate inhibition of insulin release by the pancreas to conserve glucose and to shift fuel metabolism of muscle in the direction of fatty acid oxidation. These physiological responses, typical of the stress conditions, are demonstrated to be detrimental for the functioning of different organs like the cardiac muscle when they become chronic. Indeed, a common feature of many pathological conditions involving over-activation of the adrenergic system is the development of metabolic alterations which can include insulin resistance, altered glucose and lipid metabolism and mitochondrial dysfunction. These patterns are involved with a variably extent among the different pathologies , however they are in general strictly correlated to the level of activation of the adrenergic system. Here we will review the effects of the different adrenergic receptors subtypes on the metabolic variation observed in important disease like Heart Failure.

  10. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    Energy Technology Data Exchange (ETDEWEB)

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with (/sup 3/H)yohimbine, whereas (/sup 3/H)clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, (/sup 3/H) clonidine and (/sup 3/H)yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of (/sup 3/H)clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations.

  11. Adrenergic receptor subtypes in the cerebral circulation of newborn piglets

    Energy Technology Data Exchange (ETDEWEB)

    Wagerle, L.C.; Delivoria-Papadopoulos, M.

    1987-06-01

    The purpose of this study was to identify the ..cap alpha..-adrenergic receptor subtype mediating cerebral vasoconstriction during sympathetic nerve stimulation in the newborn piglet. The effect of ..cap alpha../sub 1/- and ..cap alpha../sub 2/-antagonists prazosin and yohimbine on the cerebrovascular response to unilateral electrical stimulation (15 Hz, 15 V) of the superior cervical sympathetic trunk was studied in 25 newborn piglets. Regional cerebral blood flow was measured with tracer microspheres. Sympathetic stimulation decreased blood flow to the ipsilateral cerebrum hippocampus, choroid plexus, and masseter muscle. ..cap alpha../sub 1/-Adrenergic receptor blockade with prazosin inhibited the sympathetic vasoconstriction in the cerebrum, hippocampus, and masseter muscle and abolished it in the choroid plexus. ..cap alpha../sub s/-Adrenergic receptor blockade with yohimbine had no effect. Following the higher dose of yohimbine, however, blood flow to all brain regions was increased by approximately two-fold, possibly due to enhanced cerebral metabolism. These data demonstrate that vascular ..cap alpha../sub 1/-adrenergic receptors mediate vasoconstriction to neuroadrenergic stimulation in cerebral resistance vessels in the newborn piglet.

  12. Phosphoinositide metabolism and adrenergic receptors in astrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Noble, E.P.; Ritchie, T.; de Vellis, J.

    1986-03-01

    Agonist-induced phosphoinositide (PI) breakdown functions as a signal generating system. Diacylglycerol, one breakdown product of phosphotidylinositol-4,5-diphosphate hydrolysis, can stimulate protein kinase C, whereas inositol triphosphate, the other product, has been proposed to be a second messenger for Ca/sup + +/ mobilization. Using purified astrocyte cultures from neonatal rat brain, the effects of adrenergic agonists and antagonists at 10/sup -5/ M were measured on PI breakdown. Astrocytes grown in culture were prelabeled with (/sup 3/H)inositol, and basal (/sup 3/H) inositol phosphate (IP/sub 1/) accumulation was measured in the presence of Li/sup +/. Epinephrine > norepinephrine (NE) were the most active stimulants of IP/sub 1/ production. The ..cap alpha../sub 1/ adrenoreceptor blockers, phentolamine and phenoxybenzamine, added alone had no effect on IP/sub 1/ production was reduced below basal levels. Propranolol partially blocked the effects of NE. Clonidine and isoproterenol, separately added, reduced IP/sub 1/ below basal levels and when added together diminished IP/sub 1/ accumulation even further. The role of adrenergic stimulation in the production of c-AMP.

  13. Neurohumoral activation in heart failure: the role of adrenergic receptors

    OpenAIRE

    Patricia C. Brum; Rolim, Natale P. L.; BACURAU, Aline V. N.; Alessandra Medeiros

    2006-01-01

    Heart failure (HF) is a common endpoint for many forms of cardiovascular disease and a significant cause of morbidity and mortality. The development of end-stage HF often involves an initial insult to the myocardium that reduces cardiac output and leads to a compensatory increase in sympathetic nervous system activity. Acutely, the sympathetic hyperactivity through the activation of beta-adrenergic receptors increases heart rate and cardiac contractility, which compensate for decreased cardia...

  14. Association between essential hypertension and polymorphisms of beta 1 adrenergic receptor gene G1165C (Gly389Arg) in Chinese Mongolian population

    Institute of Scientific and Technical Information of China (English)

    Rile Hu; Shigang Zhao; Guangming Niu; Chunyu Zhang; Zhiguang Wang; Mingfang Jiang

    2006-01-01

    BACKGROUND: The prevalences of hypertension, cerebrovascular diseases, etc. are higher in Mongolian population because of the influence of various factors including genetics, geography, diet, etc. Therefore, it is helpful to develop researches on the genetics of various diseases including hypertension in Mongolian population.OBJECTIVE: To analyze the association between the polymorphism of beta1 adrenergic receptor (β1-AR)gene G1165C (Arg389Gly), an important candidate gene for various diseases of cardiovascular system, and essential hypertension in Mongolian population.DESIGN: A cross-sectional study.SETTINGS: Department of Neurology, the First Affiliated Hospital of Inner Mongolia Medical College; Wulate Houqi Red Cross Society.PARTICIPANTS: The survey was carried out from February 2003 to March 2005. Totally 239 Mongolian residents, whose blood relations of 3 generations were all Mongolians, were selected from Wulate Houqi, Inner Mongolia, and they were all informed with the survey and detected items. Based on the diagnostic standard of hypertension set by WHO in 1999, the subjects were divided into two groups according to the level blood pressure: ① Normal blood pressure group (n=117): systolic blood pressure (SBP) < 140 mm Hg (1 mm Hg =0.133 kPa), diastolic blood pressure (DBP) < 90 mm Hg, and those having histories of cerebrovascular disease, heart disease, diseases of liver, kidney and tiroides, and diabetes mellitus were excluded. ② Essential hypertension group (n=122): including 51 patients with simple high SBP. All the enrolled subjects had no blood relationship with each other, and had no history of miscegenation.METHODS: The body height, body mass, waist circumference and blood lipids were measured routinely, and their habits of smoking and drinking were also investigated. Peripheral venous blood (5 mL) was drawn, the genome DNA was extracted, and the polymorphisms of the β1-AR G1165C (Gly389Arg) genotype were detected with the Sequenom system

  15. Interaction between muscarinic and β-adrenergic receptors

    Institute of Scientific and Technical Information of China (English)

    Martin C. Michel

    2012-01-01

    In many tissues the parasympathetic and sympathetic nervous system regulate smooth musc tone via their transmitters aeetylcholine and noradrenaline, respectively. Direct smooth musc e e effects of acetylcholine via muscarinic receptors always promote contraction, but non-neuronal sources can importantly contribute to such stimulation. Direct smooth muscle effects of noradren- aline can promote contraction via al- and sometimes also α2-adrenoceptors but can promote re- laxation and inhibit contraction via β-adrenoceptors. I will focus on the interaction between sub- types of muscarinic and β-adrenergic receptors, largely using the urinary bladder as an exam- ple.

  16. β3 肾上腺能受体基因多态性分析及其初步应用%β3- adrenergic receptor gene polymorphism analysis and application

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Objective: To investigate the effect of β3- adrenergic receptor gene polymorphism on obesity and insulin resistance. Methods: With PCR - RFLP and PCR - dideoxy - chain - termination method of DNA sequencing, we investigated the influence of the β3- adrenergic receptor gene polymorphism on obesity, insulin resistance and lipid profile in native Chinese. Results: β3- AR 190 T→C mutation was detected among 48 diabetic patients and 32 volunteers. Conclusion:This genetic variation is likely to be involved in early onset of Type 2 diabetes. But it's not the major factor affecting on obesity and dyslipidemia.%建立 β3- 肾上腺能受体基因多态性检测方法,了解其表型特征。方法:应用 PCR-限制性片段长度多态性和 PCR-双脱氧链终止法测序技术分析 β3- 肾上腺能受体(β3-AR)基因型。结果:48 例北方汉族糖尿病人和 32 例正常对照者中均存在 β3-AR 基因 190 位 T→C 的单碱基变异,两组人群中基因型的构成比例无显著差异。结论:Arg64Arg 纯合子可能具有糖尿病早发的特点,但 β3-AR 基因不是造成肥胖、脂质紊乱的主要决定因素。

  17. Pregnancy modifies the alpha2-beta-adrenergic receptor functional balance in rabbit fat cells.

    Science.gov (United States)

    Bousquet-Mélou, A; Muñoz, C; Galitzky, J; Berlan, M; Lafontan, M

    1999-02-01

    The sympathetic nervous system controls lipolysis in fat by activation of four adrenergic receptors: beta1, beta2, beta3, and alpha2. During pregnancy, maternal metabolism presents anabolic and catabolic phases, characterized by modifications of fat responsiveness to catecholamines. The contributions of the four adrenergic receptors to adipocyte responsiveness during pregnancy have never been studied. Our aim was to evaluate the influence of pregnancy on adrenergic receptor-mediated lipolysis in rabbit white adipocytes. Functional studies were performed using subtype-selective and non-selective adrenergic receptor agonists. Overall adrenergic responsiveness was measured with the physiological agonist epinephrine. Non-adrenergic agents were used to evaluate different steps of the lipolytic cascade. The alpha2- and beta1/beta2-adrenergic receptor numbers were determined with selective radioligands. Non-adrenergic agents revealed that pregnancy induced an intracytoplasmic modification of the lipolytic cascade in inguinal but not in retroperitoneal adipocytes. Pregnancy induced an increase in beta1- and specially beta3-mediated lipolysis. The amounts of adipocyte beta1/beta2- and alpha2-adrenergic receptors were increased in pregnant rabbits. Epinephrine effects revealed an increased contribution of alpha2-adrenergic receptor-mediated antilipolysis in adipocytes from pregnant rabbits. These results indicate that pregnancy regulates adipocyte responsiveness to catecholamines mainly via the alpha2- and beta3-adrenergic pathways. Pregnancy induces an intracytoplasmic modification of the lipolytic cascade, probably via hormone-sensitive lipase, with differences according to fat location.-Bousquet-Mélou, A., C. Muñoz, J. Galitzky, M. Berlan, and M. Lafontan. Pregnancy modifies the alpha2-beta-adrenergic receptor functional balance in rabbit fat cells.

  18. Vascular adrenergic receptor responses in skeletal muscle in myotonic dystrophy

    Energy Technology Data Exchange (ETDEWEB)

    Mechler, F.; Mastaglia, F.L.

    1981-02-01

    The pharmacological responses of vascular adrenergic receptors to intravenously administered epinephrine, phentolamine, and propranolol were assessed by measuring muscle blood flow (MBF) changes in the tibialis anterior muscle using the xenon 133 clearance technique and were compared in 8 normal subjects and 11 patients with myotonic dystrophy. In cases with advanced involvement of the muscle, the resting MBF was reduced and was not significantly altered by epinephrine before or after alpha- or beta-receptor blockade. In patients in whom the tibialis anterior muscle was normal or only minimally affected clinically, a paradoxical reduction in the epinephrine-induced increase in MBF was found after alpha blockade by phentolamine, and the epinephrine-induced MBF increase was not completely blocked by propranolol as in the normal subjects. These findings point to functional alteration in the properties of vascular adrenergic receptors in muscle in myotonic dystrophy. While this may be another manifestation of a widespread cell membrane defect in the disease, the possibility that the changes are secondary to the myotonic state cannot be excluded.

  19. Electrical Stimulation Decreases Coupling Efficiency Between Beta-Adrenergic Receptors and Cyclic AMP Production in Cultured Muscle Cells

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.

    1999-01-01

    Electrical stimulation of skeletal muscle cells in culture is an effective way to simulate the effects of muscle contraction and its effects on gene expression in muscle cells. Expression of the beta-adrenergic receptor and its coupling to cyclic AMP synthesis are important components of the signaling system that controls muscle atrophy and hypertrophy, and the goal of this project was to determine if electrical stimulation altered the beta-adrenergic response in muscle cells. Chicken skeletal muscle cells that had been grown for seven days in culture were subjected to electrical stimulation for an additional two days at a pulse frequency of 0.5 pulses/sec and a pulse duration of 200 msec. At the end of this two-day stimulation period, beta-adrenergic receptor population was measured by the binding of tritium-labeled CGP-12177 to muscle cells, and coupling to cAMP synthesis was measured by Radioimmunoassay (RIA) after treating the cells for 10 min with the potent (beta)AR agonist, isoproterenol. The number of beta adrenergic receptors and the basal levels of intracellular cyclic AMP were not affected by electrical stimulation. However, the ability of these cells to synthesize cyclic AMP was reduced by approximately 50%. Thus, an enhanced level of contraction reduces the coupling efficiency of beta-adrenergic receptors for cyclic AMP production.

  20. Autoantibodies against α1 adrenergic receptor related with cardiac remodeling in hypertensive patients by clinical observation

    Institute of Scientific and Technical Information of China (English)

    李正在

    2006-01-01

    Objective To investigate the effects of autoantibodies against a adrenergic receptor on cardiac remodeling in patients with hypertension. Methods Five hundred and fifty three patients with hypertension in our hospital were selected. The autoantibodies againstα1 adrenergic receptor in sera of donor were detected by ELISA, and the Results of echocardiography were recorded. By

  1. Alpha-adrenergic receptors in rat skeletal muscle

    DEFF Research Database (Denmark)

    Rattigan, S; Appleby, G J; Edwards, S J;

    1986-01-01

    Sarcolemma-enriched preparations from muscles rich in slow oxidative red fibres contained specific binding sites for the alpha 1 antagonist, prazosin (e.g. soleus Kd 0.13 nM, Bmax 29 fmol/mg protein). Binding sites for prazosin were almost absent from white muscle. Displacement of prazosin bindin...... adrenergic receptors are present on the sarcolemma of slow oxidative red fibres of rat skeletal muscle. The presence provides the mechanistic basis for apparent alpha-adrenergic effects to increase glucose and oxygen uptake in perfused rat hindquarter.......Sarcolemma-enriched preparations from muscles rich in slow oxidative red fibres contained specific binding sites for the alpha 1 antagonist, prazosin (e.g. soleus Kd 0.13 nM, Bmax 29 fmol/mg protein). Binding sites for prazosin were almost absent from white muscle. Displacement of prazosin binding...... from sarcolemma of soleus muscle (phentolamine greater than phenylephrine greater than idazoxan greater than yohimbine) suggested that the receptors were alpha 1. Binding sites for dihydroalprenolol (beta antagonist) were also more concentrated on red than white muscle and outnumbered prazosin sites...

  2. Differential Regulation of Two Palmitoylation Sites in the Cytoplasmic Tail of the β1-Adrenergic Receptor*

    OpenAIRE

    2011-01-01

    S-Palmitoylation of G protein-coupled receptors (GPCRs) is a prevalent modification, contributing to the regulation of receptor function. Despite its importance, the palmitoylation status of the β1-adrenergic receptor, a GPCR critical for heart function, has never been determined. We report here that the β1-adrenergic receptor is palmitoylated on three cysteine residues at two sites in the C-terminal tail. One site (proximal) is adjacent to the seventh transmembrane domain and is a consensus ...

  3. N-terminal {beta}{sub 2}-adrenergic receptor polymorphisms do not correlate with bronchodilator response in asthma families

    Energy Technology Data Exchange (ETDEWEB)

    Holyroyd, K.J.; Dragwa, C.; Xu, J. [Johns Hopkins Medical Institutions, Baltimore, MD (United States)] [and others

    1994-09-01

    Family and twin studies have suggested that susceptibility to asthma is inherited. One clinically relevant phenotype in asthma is the bronchodilator response to beta adrenergic therapy (reversibility) which may also be inherited and vary among asthmatics. Two polymorphisms of the {beta}{sub 2}-adrenergic receptor common to both asthmatic and normal individuals have been reported. One polymorphism, an amino acid polymorphism at position 16, correlated in one study with the need for long-term corticosteriod use in a population of asthmatics. It is conceivable that the increased use of corticosteroids needed to control symptoms in these patients may be explained by a decreased responsiveness to brochodilators mediated through this amino acid polymorphism in the {beta}{sub 2}-adrenergic receptor. However, the response to {beta}{sub 2} bronchodilators was not tested in these patients. In our Dutch asthma families, DNA sequencing of the {beta}{sub 2}-adrenergic receptor has been performed for N-terminal polymorphisms at amino acid positions 16 and 27 in over 100 individuals, and no correlation was found with the increase of FEV{sub 1} in response to bronchodilator. Linkage analysis between bronchodilator response and marker D5S412 near the {beta}{sub 2}-adrenergic receptor gene was performed in 286 sibpairs from these families. Using a bronchodilator response of >10% in FEV{sub 1} as a qualitative definition of affected individuals, there were 145 unaffected sibpairs, 121 sibpairs where one was affected, and 20 in which both were affected. Linear regression analysis of these sibpair data suggested possible linkage (p=0.007). This supports further examination of the {beta}{sub 2}-adrenergic receptor and its regulatory regions for polymorphisms that correlate with the bronchodilator response in asthma families.

  4. Purification and reconstitution of the human platelet. cap alpha. /sub 2/-adrenergic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Regan, J.W.; Cerione, R.A.; Nakata, H.; Benovic, J.L.; DeMarinis, R.M.; Caron, M.G.; Lefkowitz, R.J.

    1986-05-01

    Human platelet ..cap alpha../sub 2/-adrenergic receptors have been purified approx.80,000 fold to apparent homogeneity by a five step chromatographic procedure. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of radioiodinated protein from purified receptor preparations shows a single major band of M/sub r/ 64,000. The competitive binding of ligands to the purified receptor protein shows the proper ..cap alpha../sub 2/-adrenergic specificity. The ..cap alpha../sub 2/-adrenergic receptor contains an essential sulfhydryl residues. Thus, exposure of the purified receptor to the sulfhydryl specific reagent, phenylmercuric chloride (PMC), resulted in a 80% loss of binding activity. This loss of binding activity was prevented when exposure to PMC was done in the presence of ..cap alpha../sub 2/-adrenergic ligands and it was reversed by subsequent exposure to dithiothreitol. Partial proteolysis of purified ..cap alpha../sub 2/-adrenergic receptors was obtained with S. aureus V-8 protease, ..cap alpha..-chymotrypsin and papain. In a comparison with purified ..beta../sub 2/-adrenergic receptors no common partial proteolytic products were found. Partially purified preparations of the ..cap alpha../sub 2/-adrenergic receptor were successfully reconstituted into phospholipid vesicles with the inhibitory guanyl nucleotide-binding regulatory protein, N/sub i/. In these reconstituted preparations, epinephrine could stimulate, and phentolamine could block, the GTPase activity of N/sub i/.

  5. ß2 -adrenergic receptor Thr164IIe polymorphism, blood pressure and ischaemic heart disease in 66¿750 individuals

    DEFF Research Database (Denmark)

    Thomsen, M; Dahl, Morten; Tybjaerg-Hansen, A;

    2012-01-01

    The ß(2) -adrenergic receptor (ADRB2) is located on smooth muscle cells and is an important regulator of smooth muscle tone. The Thr164Ile polymorphism (rs1800888) in the ADRB2 gene is rare but has profound functional consequences on receptor function and could cause lifelong elevated smooth musc...... tone. We tested the hypothesis that Thr164Ile is associated with increased blood pressure, increased frequency of hypertension and increased risk of cardiovascular disease (CVD)....

  6. Recent progress in α1-adrenergic receptor research

    Institute of Scientific and Technical Information of China (English)

    Zhong-jian CHEN; Kenneth P MINNEMAN

    2005-01-01

    α1-Adrenergic receptors (AR) play an important role in the regulation of physiological responses mediated by norepinephrine and epinephrine, particularly in the cardiovascular system. The three cloned α1-AR subtypes (α1A, α1B, and α1D)are G protein-coupled receptors that signal through the Gq/11 signaling pathway,each showing distinct pharmacological properties and tissue distributions.However, due to the lack of highly subtype-selective drugs, the functional rolesof individual subtypes are still not clear. Development of new subtype-specific drugs will greatly facilitate the identification of the functions of each subtype.Conopeptide ρ-TIA has been found to be a new α1B-AR selective antagonist withdifferent modes of inhibition at α1-AR subtypes. In addition, recent studies using genetically engineered mice have shed some light on α1-AR functions in vivo,especially in the cardiovascular system and brain. Several proteins have been shown to interact directly with particular α1-AR, and may be important in regulating receptor function. Receptor heterodimerization has been shown to be important for cell surface expression, signaling and internalization. These new observations are likely to help elucidate the functional roles of individual α1-AR subtypes.

  7. Association of β1 and β3 adrenergic receptors gene polymorphisms with insulin resistance and high lipid profiles related to type 2 diabetes and metabolic syndrome.

    Science.gov (United States)

    Burguete-Garcia, Ana I; Martinez-Nava, Gabriela A; Valladares-Salgado, Adan; Bermudez Morales, V H; Estrada-Velasco, Barbara; Wacher, Niels; Peralta-Romero, Jesus; Garcia-Mena, Jaime; Parra, Esteban; Cruz, Miguel

    2014-06-01

    Antecedentes: Entre los diversos genes asociados a la diabetes tipo 2 (DT2), los receptores –adrenérgicos– son excelentes candidatos para estudiar en la población mexicana dada la alta prevalencia de estas patologías. El objetivo de este trabajo fue analizar la asociación de polimorfismos en los genes ADRB1 (rs1801253) (Arg389Gly) y ADRB3 (Trp64Arg) con DT2 y SM. Métodos: Se estudiaron 445 pacientes con Síndrome Metabólico, 502 con diabetes tipo 2 y 552 controles sanos. Se evaluaron las características antropométricas, perfil bioquímico completo y los polimorfismos Arg389Gly y Trp64Arg SNPs se determinaron mediante ensayos TaqMan. El análisis de datos fue ajustado por porcentaje de ancestralidad. Resultados: Para la variante ADRB1 Arg389Gly se observó una asociación estadísticamente significativa con un aumento de los niveles de LDL (P diabetes tipo 2.

  8. GENETIC VARIATION IN THE ALPHA1B - ADRENERGIC RECEPTOR AND VASCULAR RESPONSE

    Science.gov (United States)

    Adefurin, Abiodun; Ghimire, Laxmi V.; Kohli, Utkarsh; Muszkat, Mordechai; Sofowora, Gbenga G.; Li, Chun; Levinson, Rebecca T.; Paranjape, Sachin Y.; Stein, C. Michael; Kurnik, Daniel

    2016-01-01

    α1B- adrenergic receptors contribute to vasoconstriction in humans. We tested the hypothesis that variation in the ADRA1B gene contributes to interindividual variability and ethnic differences in adrenergic vasoconstriction. We measured dorsal hand vein responses to increasing doses of phenylephrine in 64 Caucasians and 41 African-Americans and genotyped 34 ADRA1B variants. We validated findings in another model of catecholamine-induced vasoconstriction, the increase in mean arterial pressure (ΔMAP) during a cold pressor test (CPT). One ADRA1B variant, rs10070745, present in 14 African-American heterozygotes but not in Caucasians, was associated with a lower phenylephrine ED50 (geometric mean [95% CI], 144 [69–299] ng/ml) compared to 27 African-American non-carriers (208 [130–334] ng/ml; P=0.015) and contributed to the ethnic differences in ED50. The same variant was also associated with a greater ΔMAP during CPT (P=0.008). In conclusion, ADRA1B rs10070745 was significantly associated with vasoconstrictor responses after adrenergic stimulation and contributed to the ethnic difference in phenylephrine sensitivity. PMID:27089938

  9. Species differences in the localization and number of CNS beta adrenergic receptors: Rat versus guinea pig

    Energy Technology Data Exchange (ETDEWEB)

    Booze, R.M.; Crisostomo, E.A.; Davis, J.N.

    1989-06-01

    The localization and number of beta adrenergic receptors were directly compared in the brains of rats and guinea pigs. The time course of association and saturability of (125I)cyanopindolol (CYP) binding to slide-mounted tissue sections was similar in rats (Kd = 17 pM) and guinea pigs (Kd = 20 pM). The beta-1 and beta-2 receptor subtypes were examined through the use of highly selective unlabeled receptor antagonists, ICI 118,551 (50 nM) and ICI 89,406 (70 nM). Dramatic species differences between rats and guinea pigs were observed in the neuroanatomical regional localization of the beta adrenergic receptor subtypes. For example, in the thalamus prominent beta-1 and beta-2 receptor populations were identified in the rat; however, the entire thalamus of the guinea pig had few, if any, beta adrenergic receptors of either subtype. Hippocampal area CA1 had high levels of beta-2 adrenergic receptors in both rats and guinea pigs but was accompanied by a widespread distribution of beta-2 adrenergic receptors only in rats. Quantitative autoradiographic analyses of 25 selected neuroanatomical regions (1) confirmed the qualitative differences in CNS beta adrenergic receptor localization, (2) determined that guinea pigs had significantly lower levels of beta adrenergic receptors than rats and (3) indicated a differential pattern of receptor subtypes between the two species. Knowledge of species differences in receptor patterns may be useful in designing effective experiments as well as in exploring the relationships between receptor and innervation patterns. Collectively, these data suggest caution be used in extrapolation of the relationships of neurotransmitters and receptors from studies of a single species.

  10. The impact of β 2 adrenergic receptor polymorphisms on the outcomes in cardiovascular diseases

    Directory of Open Access Journals (Sweden)

    Ersilia Cipolletta

    2014-12-01

    Full Text Available Cardiovascular diseases (CVD include a heterogeneous group of multifactorial conditions and represent the major health problem in the western society. Many studies have evidenced that inter-individual variability affects the prognosis and the response to pharmacological treatment in patients with CVD. The identification of genetic markers to select patients more susceptible to develop cardiovascular complications has a therapeutic interest for undertaking individualized therapeutic approach. The sympathetic nervous system acts through adrenergic receptor subtypes and plays a key role in the development and prognosis of CVD. In particular, β-2 adrenergic receptors (β2AR, expressed in a wide variety of tissues, are critical regulators of cardiac output, peripheral vascular resistance and metabolism. Several variations with multiple single-nucleotide polymorphisms have been identified in β2AR gene. There are 3 common β2AR polymorphisms characterized in more detail for their influence on functional receptor activity. In particular, the changing an arginine for a glycine at position 16 of the receptor protein (Arg16Gly is associated with increased agonist-induced down-regulation; the substitution of glutamine with glutamic acid at position 27 (Gln27Glu leads to resistance to down-regulation; the substitution of threonine with isoleucine (Thr164Ile at position 164 causes receptor uncoupling from the G protein. Many studies have indicated the association of β2AR polymorphisms with various cardiovascular and metabolic diseases and have contributed to indicate the β2AR gene variants an appropriate target for investigating possible links between receptor polymorphisms, drug responses and susceptibility to CVD. However, the reports on the association of β2AR polymorphisms with clinical outcomes of CVD have been contradictory. In this review, we will illustrate the effects of β2ARs genetic variability on the management of CVD.

  11. β2-adrenergic receptor Thr164Ile polymorphism, obesity, and diabetes

    DEFF Research Database (Denmark)

    Thomsen, Mette; Dahl, Morten; Tybjærg-Hansen, Anne;

    2012-01-01

    The β(2)-adrenergic receptor (ADRB2) influences regulation of energy balance by stimulating catecholamine-induced lipolysis in adipose tissue. The rare functional ADRB2rs1800888(Thr164Ile) polymorphism could therefore influence risk of obesity and subsequently diabetes.......The β(2)-adrenergic receptor (ADRB2) influences regulation of energy balance by stimulating catecholamine-induced lipolysis in adipose tissue. The rare functional ADRB2rs1800888(Thr164Ile) polymorphism could therefore influence risk of obesity and subsequently diabetes....

  12. 中国肥胖患者β_2 肾上腺素受体基因多态性的研究%Polymorphism in β_2 Adrenergic Receptor Gene in Chinese Population with Obesity

    Institute of Scientific and Technical Information of China (English)

    吴红梅; 白怀; 范平; 刘瑞; 刘宇; 刘秉文

    2009-01-01

    Objective To investigate the variation of β_2 adrenergic receptor (β_2AR) gene and its association with obesity in Chinese population. Methods The allele of β_2AR gene at Argl6Gly and Gln27Glu sites were analysed with polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) in 396 people with Han nationality in Chengdu, among whom 126 had obesity. Results The allele frequencies of Arg and Gly at Argl6Gly site were 0. 571 and 0. 429 for the obese people, and 0. 559 and 0. 441 for the non-obese people, respectively. The allele frequencies of Gin and Glu at Gln27Glu site were 0. 920 and 0. 080 for the obese people, and 0. 916 and 0. 084 for the non-obese people, respectively. No significant differences were found in the genotype frequencies of the two sites between non-obese and obese people. The non-obese females and obese males with genotype Arg/Arg at Argl6Gly site had elevated serum TC and LDL-C levels compared with those who carried Arg/ Gly or Gly/Gly (P0.05).在Arg16Gly位点,非肥胖组女性和肥胖组男性Arg/Arg基因型携带者血清 TC 和 LDLC 水平分别高于Arg/Gly和Gly/Gly基因型携带者(P0.05).结论 β_2AR基因Arg16Gly和Gln27Glu多态性与成都地区中国汉族人肥胖无关联,但Arg16Gly位点对特定性别非肥胖及肥胖人群血清TC、LDLC及部分载脂蛋白水平有一定影响.

  13. Adrenergic receptors and gastric secretion in dogs. Is a "tonic balance" relationship between vagal and beta 2-adrenergic activity a possibility?

    DEFF Research Database (Denmark)

    Gottrup, F; Hovendal, C; Bech, K

    1984-01-01

    The relative influence of adrenergic receptors on gastric acid secretion in the dog stomach with different vagal activity or "tone" is almost unknown. beta-adrenoceptors seem to be most important for the direct effect of adrenergic stimulation on acid secretion. In this study the effects of vagot...

  14. Prenatal exposure to methylmercury alters development of adrenergic receptor binding sites in peripheral sympathetic target tissues

    Energy Technology Data Exchange (ETDEWEB)

    Slotkin, T.A.; Orband, L.; Cowdery, T.; Kavlock, R.J.; Bartolome, J.

    1987-01-01

    In order to assess the impact of prenatal exposure to methylmercury on sympathetic neurotransmission, effects on development of adrenergic receptor binding sites in peripheral tissues was evaluated. In the liver, methylmercury produced a dose-dependent increase in alpha/sub 1/, alpha/sub 2/, and beta-receptor binding of radioliganda throughout the first 5 weeks of postnatal life. Similarly, renal alpha-receptor subtypes showed increased binding capabilities, but binding to alpha-receptor sites was reduced. At least some of the changes in receptors appear to be of functional significance, as physiological reactivity to adrenergic stimulation is altered in the same directions in these two tissues. The actions of methylmercury displayed tissue specificity in that the same receptor populations were largely unaffected in other tissues (lung, heart). These results suggest that methylmercury exposure in utero alters adrenergic responses through targeted effects on postsynaptic receptor populations in specific tissues.

  15. Multiple interactions between the alpha2C- and beta1-adrenergic receptors influence heart failure survival

    Directory of Open Access Journals (Sweden)

    Case Karen L

    2008-10-01

    Full Text Available Abstract Background Persistent stimulation of cardiac β1-adrenergic receptors by endogenous norepinephrine promotes heart failure progression. Polymorphisms of this gene are known to alter receptor function or expression, as are polymorphisms of the α2C-adrenergic receptor, which regulates norepinephrine release from cardiac presynaptic nerves. The purpose of this study was to investigate possible synergistic effects of polymorphisms of these two intronless genes (ADRB1 and ADRA2C, respectively on the risk of death/transplant in heart failure patients. Methods Sixteen sequence variations in ADRA2C and 17 sequence variations in ADRB1 were genotyped in a longitudinal study of 655 white heart failure patients. Eleven sequence variations in each gene were polymorphic in the heart failure cohort. Cox proportional hazards modeling was used to identify polymorphisms and potential intra- or intergenic interactions that influenced risk of death or cardiac transplant. A leave-one-out cross-validation method was utilized for internal validation. Results Three polymorphisms in ADRA2C and five polymorphisms in ADRB1 were involved in eight cross-validated epistatic interactions identifying several two-locus genotype classes with significant relative risks ranging from 3.02 to 9.23. There was no evidence of intragenic epistasis. Combining high risk genotype classes across epistatic pairs to take into account linkage disequilibrium, the relative risk of death or transplant was 3.35 (1.82, 6.18 relative to all other genotype classes. Conclusion Multiple polymorphisms act synergistically between the ADRA2C and ADRB1 genes to increase risk of death or cardiac transplant in heart failure patients.

  16. Alpha 2 adrenergic receptors in hyperplastic human prostate: identification and characterization using (/sup 3/H) rauwolscine

    Energy Technology Data Exchange (ETDEWEB)

    Shapiro, E.; Lepor, H.

    1986-05-01

    (/sup 3/H)Rauwolscine ((/sup 3/H)Ra), a selective ligand for the alpha 2 adrenergic receptor, was used to identify and characterize alpha 2 adrenergic receptors in prostate glands of men with benign prostatic hyperplasia. Specific binding of (/sup 3/H)Ra to prostatic tissue homogenates was rapid and readily reversible by addition of excess unlabelled phentolamine. Scatchard analysis of saturation experiments demonstrates a single, saturable class of high affinity binding sites (Bmax = 0.31 +/- 0.04 fmol./microgram. DNA, Kd = 0.9 +/- 0.11 nM.). The relative potency of alpha adrenergic drugs (clonidine, alpha-methylnorepinephrine and prazosin) in competing for (/sup 3/H)Ra binding sites was consistent with the order predicted for an alpha 2 subtype. The role of alpha 2 adrenergic receptors in normal prostatic function and in men with bladder outlet obstruction secondary to BPH requires further investigation.

  17. 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.

  18. Association of Polymorphisms of β3—Adrenergic Receptor,Angiotensinogen and Angiotensin—Converting Enzyme Gene with Hypertension in type 2 DM

    Institute of Scientific and Technical Information of China (English)

    丁国宪; 沈捷; 等

    2002-01-01

    Objective To explore the relationship between the mutant genes of ACE,ATN,β3-AR and hypertension in patients with type 2DM.Methods 281 recruited Chinese subjects were divided into two groups according to the oral glucose tolerance test (OGTT):(1)non-diabetes group including normal and impaired glucose tolerance(NGT,IGT):169cases;(2)Type 2 diabetes mellitus(DM):112 cases.The subjects were genotyped for the ACE gene,the ATN gene and the codon 64 of β3-AR gene polymorphisms by applying polymerase chain reaction(PCR),PCR restriction fragment-length polymorphisms screening with the use of endonuclease.Results Our study found that the frequency of D/D genotype and D allele of ACE gene,a/a genotype and an allele of ATN gene in HT patients without DM were increased (P all<0.05);that the frequency of codon 64 mutation of β3-AR gene also increased in HT patients with NGT(P<0.05).In the model of multiple factors non-condition-al Logistic regression analyses,HT had relationship with history of hypertension,age and glucose tolerance(OR=10.7457,1.7804,2.0346;P=0.0004,0.0000,0.0246;respectively),with polymorphism of ATN gene,β3AR gene,ACE gene(OR=2.2736,1.9353,1.8309;P=0.0543,0.0287,0.0432;resceptively).Conclusion These results suggest that variants of ACE gene,β3AR gene,ATN gene were associated with HT in type 2 DM.

  19. Association of Polymorphisms of β3-Adrenergic Receptor,Angiotensinogen and Angiotensin-Converting Enzyme Gene with Hypertension in type 2 DM

    Institute of Scientific and Technical Information of China (English)

    丁国宪; 沈捷; 陈家伟

    2002-01-01

    ObjectiveTo explore the relationship between the mutant genes of ACE,ATN,β3-AR and hypertension in patients with type 2 DM.Methods281 recruited Chinese subjects were divided into two groups according to the mellitus (DM):112 cases.The subjects were genotyped for the ACE gene,the ATN gene and the codon 64 of β3-AR gene polymorphisms by applying polymerase chain reaction (PCR),PCR restriction fragment-length polymorphisms screening with the use of endonuclease.ResultsOur study found that the frequency of D/D genotype and D allele of ACE gene,a/a genotype and an allele of ATN gene in HT patients without DM were increased (P all <0.05);that the frequency of codon 64 mutation of β3-AR gene also increased in HT patients with NGT (P <0.05).In the model of multiple factors non-condition-al Logistic regression analyses,HT had relationship with history of hypertension,age and glucose tolerance (OR=10.745 7,1.780 4,2.034 6;P=0.000 4,0.000 0,0.024 6;respectively),with polymorphism of ATN gene,β3AR gene,ACE gene (OR=2.273 6,1.935 3,1.830 9;P=0.054 3,0.028 7,0.043 2;resceptively).ConclusionThese results suggest that variants of ACE gene,β3AR gene,ATN gene were associated with HT in type 2 DM.``

  20. Genetic polymorphisms of human β-adrenergic receptor genes and their association with obesity%人类β-肾上腺素受体基因的遗传多态性及其与肥胖的关系

    Institute of Scientific and Technical Information of China (English)

    刘昭前; 莫玮; 黄琼; 周宏灏

    2007-01-01

    The prevalent rates of overweight and obesity are steadily increasing all over the world. Previous studies of some candidate genes have indicated that most of the genes are associated with obesity in human adipose tissue. As much as 40% of the variations in body mass could be attributed to genetic difference. The β-adrenergic receptor (β-AR) plays a major role in the regulation of energy balance in humans. A high sympathetic nervous system activity has been shown to be associated with obesity and is believed to have pathogenetic relevance. Several common single nucleotide polymorphisms (SNPs) including Gly389Arg in β1-AR, Gln27Glu in β2-AR, and Trp64Arg in β3-AR in humans could alter receptor function and these variations ofβ-ARs were shown to have certain association with obesity. Here we summarize the genetic polymorphisms of human β-ARs and their potential impacts to obesity.%在世界范围内,肥胖和超重的发生率正在稳步增长.过去有关候选基因的大量研究已经表明,大多数基因与人类脂肪组织中肥胖的发生相关.与人体体质量相关的40%以上的基因变异可以产生遗传差异.β-肾上腺素受体在人体能量平衡调节中扮演重要作用,交感神经系统的高度激活被认为与肥胖的发生密切相关.β-肾上腺素受体的单核苷酸多态性如β1-肾上腺素受体Gly389Arg,β2-肾上腺素受体Gln27Glu和β3-肾上腺素受体Trp64Arg已经被证明能够改变受体的功能,并与肥胖的发生有关.本文就β-肾上腺素受体的遗传多态性以及它们在肥胖发生中的作用作一综述.

  1. Impact of the Tamsulosin in Alpha Adrenergic Receptor of Airways at Patients with Increased Bronchial Reactibility

    OpenAIRE

    Mustafa, Lirim; Ilazi, Ali; Dauti, Arta; Islami, Pellumb; Kastrati, Bashkim; Islami, Hilmi

    2015-01-01

    Objective: In this work, effect of tamsulosin as antagonist of alpha1A and alpha1B adrenergic receptor and effect of agonists of beta2 adrenergic receptor–salbutamol in patients with increased bronchial reactibility was studied. Methods: Parameters of the lung function are determined with Body plethysmography six (6) hours after administration of tamsulosin. Raw and ITGV were registered and specific resistance (SRaw) was calculated as well. Tamsulosin was administered in per os manner as a pr...

  2. [Polymorphisms of 2B-adrenergic receptor and endothelial NO-Synthase genes in genesis of the hereditary sick sinus node syndrome].

    Science.gov (United States)

    Chernova, A A; Nikulina, S Iu; Shul'man, V A; Kukushkina, T S; Voevoda, M I; Maksimov, V N

    2011-01-01

    In this work we have demonstrated for the first time on the clinico-genetic material association between hereditary sick sinus node syndrome (SSNS) ADRA2B and eNOS genes polymorphisms. We have established predominance of homozygote genotype of more rare DD allele in patients with SSNS (28%) compared with subjects of control group (8.99%). We have found predominance of heterozygote genotype 4a/4b in patients with SSNS compared with subjects of control group (41.8 and 25.39%, respectively). The data obtained allow to suggest that eNOS gene polymorphism might be associated with SSNS.

  3. Altered adrenergic response and specificity of the receptors in rat ascites hepatoma AH130.

    Science.gov (United States)

    Sanae, F; Miyamoto, K; Koshiura, R

    1989-11-15

    Adenylate cyclase activation through adrenergic receptors in rat ascites hepatoma (AH) 130 cells in response to adrenergic drugs was studied, and receptor binding and displacement were compared with those of normal rat hepatocytes. Epinephrine (Epi) and norepinephrine (NE) activated AH130 adenylate cyclase about half as much as isoproterenol (IPN) but equaled IPN after treatment with the alpha-antagonist phentolamine or islet-activating protein (IAP). The three catecholamines in hepatocytes were similar regardless of phentolamine or IAP. These catecholamines activated adenylate cyclase in order of IPN greater than NE greater than Epi in AH130 cells but IPN greater than Epi greater than NE in hepatocytes. We then used the alpha 1-selective ligand [3H]prazosin, the alpha 2-selective ligand [3H]clonidine, and the beta-ligand [125I]iodocyanopindolol [( 125I]ICYP), and found that AH130 cells had few prazosin-binding sites, about eight times as many clonidine-binding sites with high affinity, and many more ICYP-binding sites than in hepatocytes. The dissociation constant (Ki) of the beta 1-selective drug metoprolol by Hofstee plots for AH130 cells was lower than that for hepatocytes. The inhibition of specific ICYP binding by the beta 2-selective agonist salbutamol for AH130 cells gave only one Ki value which was much higher than both high and low Ki values of the drug for hepatocytes. These findings indicate that the alpha- and beta-adrenergic receptors in hepatocytes are predominantly alpha 1-type and beta 2-type, but that those in AH130 cells are predominantly alpha 2-type and beta 1-type, and the low adrenergic response of AH130 cells is due to the dominant appearance of alpha 2-adrenergic receptors, linked with the inhibitory guanine-nucleotide binding regulatory protein, instead of alpha 1-adrenergic receptors, and beta 1-adrenergic receptors with low affinity for the hormone.

  4. Characterization and regulation of. beta. /sub 2/-adrenergic receptors in rat vas deferens

    Energy Technology Data Exchange (ETDEWEB)

    May, J.M.

    1985-01-01

    ..beta../sub 2/-Adrenergic receptors in rat vas deferens were examined by measuring the binding of /sup 125/I-pindolol (/sup 125/IPIN) to membrane preparations and the inhibition of evoked contractions in intact tissues. /sup 125/IPIN labeled a single class of binding sites with mass action kinetics. Affinity constants for ..beta..-adrenergic receptor antagonists calculated from both binding and functional experiments agreed well, suggesting that /sup 125/IPIN labels the functional ..beta../sub 2/-adrenergic receptor. n-Bromoacetylalprenololmenthane (BAAM) was used to decrease receptor density so that agonist affinity constants could be determined functionally. Treatment of tissues with BAAM decreased the functional potencies of agonists. Higher concentrations of BAAM decreased the maximum tissue response. Affinity constants for agonists calculated after BAAM treatment were compared to affinity constants determined from binding studies done under conditions designed to promote high or low affinity agonist binding. Functional affinity constants for isoproterenol and salbutamol agreed with the low affinity binding constants, suggesting that the low affinity form of the receptor initiates the functional response. Because acute denervation of vasa deferentia did not alter the density of /sup 125/IPIN binding sites, the sites are probably post-junctional. Chronic infusion of isoproterenol reduced the potency of isoproterenol, the maximum tissue response, and the receptor density. These results suggest that ..beta..-adrenergic receptor density and responsiveness in rat vas deferens are not affected by removing catecholamine sources, but receptor density and responsiveness can be decreased by increasing agonist concentration at the receptor.

  5. The role of adrenergic receptors in the motility of duodenum and choledochoduodenal junction in the pig.

    Science.gov (United States)

    Blichowski, A; Andrzejewski, W; Gaszyński, W; Kozulski, W

    1977-01-01

    The role of adenergic receptors in the motility of duodenum and choledochoduodenal junction in the pig. Acta Physiol. Pol., 1977, 28 (6): 521-528. The choldeochoduodenal junction in the Vietnamese pig is functionally and anatomically a part of duodenal wall. In view of this, investigations were carried out for establishing the role of adrenergic receptors in the development of motor function of this part of the intestinal tract. The experiments were performed on domestic Vietnamese pigs (Sus scrofa domestica) and they showed that after stimulation of alpha and beta adrenergic receptors the motor activity of the duodenal muscular coat and the choledochoduodenal junction is inhibited. The obtained results suggest similar reactions of the adrenergic receptors in both examined parts of the intestinal tract in the pig.

  6. Relationship between human evolution and neurally mediated syncope disclosed by the polymorphic sites of the adrenergic receptor gene α2B-AR.

    Directory of Open Access Journals (Sweden)

    Tomoyoshi Komiyama

    Full Text Available The objective of this study was to clarify the effects of disease on neurally mediated syncope (NMS during an acute stress reaction. We analyzed the mechanism of the molecular interaction and the polymorphisms of the alpha-2 adrenoreceptor (α2B-AR gene as the potential psychiatric cause of incentive stress. We focused on the following three genotypes of the repeat polymorphism site at Glu 301-303 in the α2B-AR gene: Glu12/12, Glu12/9, and Glu9/9. On the basis of our clinical research, NMS is likely to occur in people with the Glu12/9 heterotype. To verify this, we assessed this relationship with the interaction of Gi protein and adenylate cyclase by in silico analysis of the Glu12/9 heterotype. By measuring the difference in the dissociation time of the Gi-α subunit twice, we found that the Glu12/9 heterotype suppressed the action of adenylate cyclase longer than the Glu homotypes. As this difference in the Glu repeat number effect is thought to be one of the causes of NMS, we investigated the evolutionary significance of the Glu repeat number. Glu8 was originally repeated in simians, while the Glu12 repeats occurred over time during the evolution of bipedalism in humans. Taken with the Glu12 numbers, NMS would likely become a defensive measure to prevent significant blood flow to the human brain.

  7. [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.

  8. Efecto de la dieta y de los genes PPARγ2 y b2-adrenérgico en el metabolismo energético y en la composición corporal de mujeres obesas Effect of diet and PPARγ2 and b2-adrenergic receptor genes on energy metabolism and body composition in obese women

    Directory of Open Access Journals (Sweden)

    E. L. Rosado

    2006-06-01

    Glu la ingesta de AGPI puede resultar en mayor pérdida de peso corporal.Objective: To evaluate the effect of diet and PPARγ2 and b2-adrenergic receptor genes on energy metabolism and body composition in obese women. Material and methods: 60 obese women, aged 34.59 ± 7.56 years were studied at the Department of Physiology and Nutrition at Navarra University. Anthropometric, biochemical,metabolic and molecular evaluations were carried out, and the women were submitted to short-term and longterm hypocaloric diets, varying the macronutrients. The groups were formed according to gene polymorphism, as follows: Pro12Pro(PPARγ2/Gln27Gln (ί2-adrenergic receptor genes - A, Pro12Pro (PPARγ2/Gln27Glu (b2- adrenergic receptor genes - B, Pro12Pro (PPARγ2/Glu27Glu (b2-adrenergic receptor genes-C and Pro1Ala (PPARγ2/Gln27Glu (b2-adrenergic receptor genes - D. Results: In group A, fat oxidation was correlated positively with body mass index (BMI, but an increase in fat and saturated fatty acids (SFA in the diet did not reflect in increased oxidation. In group B, total fat and SFA intake did not lead to fat oxidation increase. In group C, fat and complex carbohydrates (CHO resulted in lower fat oxidation, and long-term increase of monounsaturated fatty acid (MUFA intake resulted in increase of CHO oxidation and smaller weight loss. In group D, greater energy expenditure was obtained after diet high in SFA in a short-term, and fat basal and postprandial oxidation correlated positively with its intake. Hypocaloric diet high in polyunsaturated fatty acid (PUFA resulted inincrease of fat oxidation. Conclusions: Polymorphism in PPARγ2 gene resulted in increased fat oxidation, regardless of genotype of ί2- adrenergic receptor gene. It is recommended control of the total intake of fats and SFA in Pro12Pro/Gln27Gln and Pro12Pro/Gln27Glu, and complex CHO and MUFA in Pro12Pro/Glu27Glu. In Pro12Ala/Gln27Glu, AGPI intake can result in greater body weight loss.

  9. Changes in postnatal norepinephrine alter alpha-2 adrenergic receptor development.

    Science.gov (United States)

    Sanders, J D; Happe, H K; Bylund, D B; Murrin, L C

    2011-09-29

    Alpha-2 adrenergic receptors (A2AR) regulate multiple brain functions and are enriched in developing brain. Studies demonstrate norepinephrine (NE) plays a role in regulating brain maturation, suggesting it is important in A2AR development. To investigate this we employed models of NE absence and excess during brain development. For decreases in NE we used N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride (DSP4), a specific noradrenergic neurotoxin. Increased noradrenergic terminal density was produced by methylazoxymethanol acetate (MAM) treatment. A2AR density was assayed with [(3)H]RX821002 autoradiography. DSP4 lesions on postnatal day (PND) 3 produce A2AR decreases in many regions by PND 5. A2AR recover to control levels by PND 15 and 25 and there is no further change in total receptor density. We also assayed A2AR in brains lesioned with DSP4 on PND 13, 23, 33 and 43 and harvested 22 days post-lesion. A2AR levels remain similar to control at each of these time points. We examined A2AR functionality and high affinity state with epinephrine-stimulated [(35)S]GTPγS and [(125)I]p-iodoclonidine autoradiography, respectively. On PND 25, control animals and animals lesioned with DSP4 on PND 3 have similar levels of [(35)S]GTPγS incorporation and no change in high affinity state. This is in contrast to increases in A2AR high affinity state produced by DSP4 lesions of mature brain. We next investigated A2AR response to increases in norepinephrine levels produced by MAM. In contrast to DSP4 lesions, increasing NE results in a large increase in A2AR. Animals treated with MAM on gestational day 14 had cortical [(3)H]RX821002 binding 100-200% greater than controls on PND 25, 35, 45, 55 and 65. These data indicate that NE regulation of A2AR differs in developing and mature brain and support the idea that NE regulates A2AR development and this has long term effects on A2AR function.

  10. Impact of the Tamsulosin in Alpha Adrenergic Receptor of Airways at Patients with Increased Bronchial Reactibility

    Science.gov (United States)

    Mustafa, Lirim; Ilazi, Ali; Dauti, Arta; Islami, Pellumb; Kastrati, Bashkim; Islami, Hilmi

    2015-01-01

    Objective: In this work, effect of tamsulosin as antagonist of alpha1A and alpha1B adrenergic receptor and effect of agonists of beta2 adrenergic receptor–salbutamol in patients with increased bronchial reactibility was studied. Methods: Parameters of the lung function are determined with Body plethysmography six (6) hours after administration of tamsulosin. Raw and ITGV were registered and specific resistance (SRaw) was calculated as well. Tamsulosin was administered in per os manner as a preparation in the shape of the capsules with a brand name of “Prolosin”, produced by Niche Generics Limited, Hitchin, Herts. Results: After six (6) hours of administration of tamsulosin, results gained indicate that blockage of alpha1A and alpha1B-adrenergic receptor (0.8 mg per os) has not changed significantly (p > 0.1) the bronchomotor tonus of tracheobronchial tree in comparison to the check-up that has inhaled salbutamol agonist of adrenergic beta2 receptor (2 inh. x 0.2 mg), (p < 0.05). Blood pressure suffered no significant decrease following administration of the 0.8 mg dose of tamsulosin. Conclusion: This suggests that even after six hours of administration of tamsulosin, and determining of lung function parameters, the activity of alpha1A and alpha1B-adrenergic receptor in the smooth bronchial musculature has not changed in patients with increased bronchial reactibility. PMID:26543414

  11. 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....

  12. Differential modulation of Beta-adrenergic receptor signaling by trace amine-associated receptor 1 agonists.

    Directory of Open Access Journals (Sweden)

    Gunnar Kleinau

    Full Text Available Trace amine-associated receptors (TAAR are rhodopsin-like G-protein-coupled receptors (GPCR. TAAR are involved in modulation of neuronal, cardiac and vascular functions and they are potentially linked with neurological disorders like schizophrenia and Parkinson's disease. Subtype TAAR1, the best characterized TAAR so far, is promiscuous for a wide set of ligands and is activated by trace amines tyramine (TYR, phenylethylamine (PEA, octopamine (OA, but also by thyronamines, dopamine, and psycho-active drugs. Unfortunately, effects of trace amines on signaling of the two homologous β-adrenergic receptors 1 (ADRB1 and 2 (ADRB2 have not been clarified yet in detail. We, therefore, tested TAAR1 agonists TYR, PEA and OA regarding their effects on ADRB1/2 signaling by co-stimulation studies. Surprisingly, trace amines TYR and PEA are partial allosteric antagonists at ADRB1/2, whereas OA is a partial orthosteric ADRB2-antagonist and ADRB1-agonist. To specify molecular reasons for TAAR1 ligand promiscuity and for observed differences in signaling effects on particular aminergic receptors we compared TAAR, tyramine (TAR octopamine (OAR, ADRB1/2 and dopamine receptors at the structural level. We found especially for TAAR1 that the remarkable ligand promiscuity is likely based on high amino acid similarity in the ligand-binding region compared with further aminergic receptors. On the other hand few TAAR specific properties in the ligand-binding site might determine differences in ligand-induced effects compared to ADRB1/2. Taken together, this study points to molecular details of TAAR1-ligand promiscuity and identified specific trace amines as allosteric or orthosteric ligands of particular β-adrenergic receptor subtypes.

  13. Biochemical and pharmacological studies of the hepatic alpha sub 1 -adrenergic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Tchakarov, L.E.

    1988-01-01

    The structure and the regulation of the hepatic {alpha}{sub 1}-adrenergic receptors have been studied in the rat. The in vitro incubation of isolated liver cells in a serum-free buffer for 4 hr leads to the conversion of the adrenergic activation of glycogen phosphorylase from an {alpha}{sub 1}- to a {beta}-adrenoceptor-mediated event. This change is associated with no change in the glycogenolytic response to vasopressin and a reduction of the glycogenolytic response to glucagon. The time-dependent shift in the adrenergic control of glycogenolysis does not influence the density or the affinity of ({sup 3}H)prazosin-labeled {alpha}{sub 1}-receptors and ({sup 3}H)CGP-12177-labeled {beta}-receptors. The change in the adrenergic control of glycogenolysis is reversed by a 30-min incubation with 50 nM lipomodulin, whereas in freshly isolated cells lipomodulin doesn't affect the predominant {alpha}-receptor response. Conversely, exposure of freshly isolated cells to a monoclonal antibody to lipomodulin in the presence of 10 {mu}M phenylephrine, or to 2 {mu}g/ml mellitin, results in a shift in the adrenergic control of glycogenolysis from {alpha}{sub 1}- to {beta}-type within 30 min. The mechanism of activation of the Ca{sup 2+}-linked receptors for vasopressin and adrenaline was studied in isolated liver cells. A novel irreversible antagonist for the {alpha}{sub 1}-adrenergic receptors, I-phenyoxybenzamine (I-POB) has been synthesized and pharmacologically characterized.

  14. Distribution of adrenergic receptors in the enteric nervous system of the guinea pig, mouse, and rat.

    Science.gov (United States)

    Nasser, Yasmin; Ho, Winnie; Sharkey, Keith A

    2006-04-10

    Adrenergic receptors in the enteric nervous system (ENS) are important in control of the gastrointestinal tract. Here we describe the distribution of adrenergic receptors in the ENS of the ileum and colon of the guinea pig, rat, and mouse by using single- and double-labelling immunohistochemistry. In the myenteric plexus (MP) of the rat and mouse, alpha2a-adrenergic receptors (alpha2a-AR) were widely distributed on neurons and enteric glial cells. alpha2a-AR mainly colocalized with calretinin in the MP, whereas submucosal alpha2a-AR neurons colocalized with vasoactive intestinal polypeptide (VIP), neuropeptide Y, and calretinin in both species. In the guinea pig ileum, we observed widespread alpha2a-AR immunoreactivity on nerve fibers in the MP and on VIP neurons in the submucosal plexus (SMP). We observed extensive beta1-adrenergic receptor (beta1-AR) expression on neurons and nerve fibers in both the MP and the SMP of all species. Similarly, the beta2-adrenergic receptor (beta2-AR) was expressed on neurons and nerve fibers in the SMP of all species, as well as in the MP of the mouse. In the MP, beta1- and beta2-AR immunoreactivity was localized to several neuronal populations, including calretinin and nitrergic neurons. In the SMP of the guinea pig, beta1- and beta2-AR mainly colocalized with VIP, whereas, in the rat and mouse, beta1- and beta2-AR were distributed among the VIP and calretinin populations. Adrenergic receptors were widely localized on specific neuronal populations in all species studied. The role of glial alpha2a-AR is unknown. These results suggest that sympathetic innervation of the ENS is directed toward both enteric neurons and enteric glia.

  15. Synthesis and characterization of arylamine derivatives of rauwolscine as molecular probes for alpha 2-adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Lanier, S.M.; Graham, R.M.; Hess, H.J.; Grodski, A.; Repaske, M.G.; Nunnari, J.M.; Limbird, L.E.; Homcy, C.J.

    1987-06-01

    The selective alpha 2-adrenergic receptor antagonist rauwolscine was structurally modified to yield a series of arylamine carboxamide derivatives, which were investigated as potential molecular probes for the localization and structural characterization of alpha 2-adrenergic receptors. The arylamine carboxamides differ in the number of carbon atoms separating the reactive phenyl moiety from the fused ring structure of the parent compound, rauwolscine carboxylate. Competitive inhibition studies with (/sup 3/H)rauwolscine in rat kidney membranes indicate that the affinity for the carboxamide derivatives is inversely related to the length of the carbon spacer arm with rauwolscine 4-aminophenyl carboxamide exhibiting the highest affinity (Kd = 2.3 +/- 0.2 nM). Radioiodination of rau-AMPC yields a ligand, /sup 125/I-rau-AMPC, which binds to rat kidney alpha 2-adrenergic receptors with high affinity, as determined by both kinetic analysis (Kd = k2/k1 = 0.016 min-1/2.1 X 10(7) M-1 min-1 = 0.76 nM) and equilibrium binding studies (Kd = 0.78 +/- 0.16 nM). /sup 125/I-rau-AMPC was quantitatively converted to the photolabile arylazide derivative 17 alpha-hydroxy-20 alpha-yohimban-16 beta-(N-4-azido-3-(/sup 125/I)iodophenyl) carboxamide (/sup 125/I-rau-AZPC). In a partially purified receptor preparation from porcine brain, this compound photolabels a major (Mr = 62,000) peptide. The labeling of this peptide is inhibited by adrenergic agonists and antagonists with a rank order of potency consistent with an alpha 2-adrenergic receptor binding site. Both /sup 125/I-rau-AMPC and the photolabile arylazide derivative, /sup 125/I-rau-AZPC, should prove useful as molecular probes for the structural and biochemical characterization of alpha 2-adrenergic receptors.

  16. Beta-Adrenergic Receptors and Mechanisms in Asthma: The New Long-Acting Beta-Agonists

    Directory of Open Access Journals (Sweden)

    Robert G Townley

    1996-01-01

    Full Text Available The objective is to review β-adrenergic receptors and mechanisms in the immediate and late bronchial reaction in asthma and the new long-acting β-agonist. This will be discussed in light of the controversy of the potential adverse effect of regular use of long-acting β-agonists. We studied the effect of formoterol on the late asthmatic response (LAR and airway inflammation in guinea-pigs. Formoterol suppressed the LAR, antigen-induced airway inflammation and hyperresponsiveness, although isoproterenol failed to inhibit these parameters. β-Adrenergic hyporesponsiveness, and cholinergic and a- adrenergic hyperresponsiveness have been implicated in the pathogenesis of asthma. A decrease in β-adrenoreceptor function can result either from exogenously administered β-agonist or from exposure to allergens resulting in a late bronchial reaction. There is increasing evidence that eosinophils, macrophages, and lymphocytes which are of primary importance in the late bronchial reaction are also modulated by β2- adrenoreceptors. In functional studies of guinea-pig or human isolated trachea and lung parenchyma, PAF and certain cytokines significantly reduced the potency of isoproterenol to reverse methacholine- or histamine-induced contraction. The effect of glucocorticoids on pulmonary β-adrenergic receptors and responses suggests an important role for glucocorticoids to increase β-adrenergic receptors and responsiveness.

  17. 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:

  18. Alpha1A-adrenergic receptor-directed autoimmunity induces left ventricular damage and diastolic dysfunction in rats.

    Directory of Open Access Journals (Sweden)

    Katrin Wenzel

    Full Text Available BACKGROUND: Agonistic autoantibodies to the alpha(1-adrenergic receptor occur in nearly half of patients with refractory hypertension; however, their relevance is uncertain. METHODS/PRINCIPAL FINDINGS: We immunized Lewis rats with the second extracellular-loop peptides of the human alpha(1A-adrenergic receptor and maintained them for one year. Alpha(1A-adrenergic antibodies (alpha(1A-AR-AB were monitored with a neonatal cardiomyocyte contraction assay by ELISA, and by ERK1/2 phosphorylation in human alpha(1A-adrenergic receptor transfected Chinese hamster ovary cells. The rats were followed with radiotelemetric blood pressure measurements and echocardiography. At 12 months, the left ventricles of immunized rats had greater wall thickness than control rats. The fractional shortening and dp/dt(max demonstrated preserved systolic function. A decreased E/A ratio in immunized rats indicated a diastolic dysfunction. Invasive hemodynamics revealed increased left ventricular end-diastolic pressures and decreased dp/dt(min. Mean diameter of cardiomyocytes showed hypertrophy in immunized rats. Long-term blood pressure values and heart rates were not different. Genes encoding sarcomeric proteins, collagens, extracellular matrix proteins, calcium regulating proteins, and proteins of energy metabolism in immunized rat hearts were upregulated, compared to controls. Furthermore, fibrosis was present in immunized hearts, but not in control hearts. A subset of immunized and control rats was infused with angiotensin (Ang II. The stressor raised blood pressure to a greater degree and led to more cardiac fibrosis in immunized, than in control rats. CONCLUSIONS/SIGNIFICANCE: We show that alpha(1A-AR-AB cause diastolic dysfunction independent of hypertension, and can increase the sensitivity to Ang II. We suggest that alpha(1A-AR-AB could contribute to cardiovascular endorgan damage.

  19. In utero Exposure to beta-2-Adrenergic Receptor Agonist Drugs and Risk for Autism Spectrum Disorders

    DEFF Research Database (Denmark)

    Gidaya, Nicole B.; Lee, Brian K.; Burstyn, Igor

    2016-01-01

    OBJECTIVES: The purpose of this study was to investigate associations between use of β-2-adrenergic receptor (B2AR) agonist drugs during pregnancy and risk for autism spectrum disorders (ASD). METHODS: A case-control study was conducted by using Denmark’s health and population registers. Among...

  20. Alpha-1 adrenergic receptor: Binding and phosphoinositide breakdown in human myometrium

    Energy Technology Data Exchange (ETDEWEB)

    Breuiller-Fouche, M.; Doualla-Bell Kotto Maka, F.; Geny, B.; Ferre, F. (INSERM U.166 Groupe de recherches sur l' Endocrinologie de la Reproduction, Maternite Baudelocque, Paris (France))

    1991-07-01

    Alpha-1 adrenergic receptors were examined in both inner and outer layers of human pregnant myometrium using radioligand binding of (3H)prazosin. (3H)prazosin bound rapidly and reversibly to a single class of high affinity binding sites in myometrial membrane preparations. Scatchard analysis gave similar values of equilibrium dissociation constants in both myometrial layers. In contrast, more alpha-1 adrenergic receptors were detected in the outer layer than in the inner layer. Antagonist inhibited (3H)prazosin binding with an order of potency of prazosin greater than phentolamine greater than idazoxan. Competition experiments have also revealed that a stable guanine nucleotide decreases the apparent affinity of norepinephrine for myometrial (3H)prazosin binding sites. The functional status of these alpha-1 adrenergic receptors was also assessed by measuring the norepinephrine-induced accumulation of inositol phosphates in myometrial tissue. Norepinephrine produced a concentration-dependent accumulation of inositol phosphates in both myometrial layers. However, norepinephrine-induced increases in inositol 1,4,5-triphosphate were only observed in the outer layer. These results indicate that alpha-1 adrenergic receptors in human myometrium at the end of pregnancy are linked to phosphoinositide hydrolysis and that this response occurs mainly in the outer layer.

  1. Modulation of nicotinic receptor channels by adrenergic stimulation in rat pinealocytes

    Science.gov (United States)

    Yoon, Jin-Young; Jung, Seung-Ryoung; Hille, Bertil

    2014-01-01

    Melatonin secretion from the pineal gland is triggered by norepinephrine released from sympathetic terminals at night. In contrast, cholinergic and parasympathetic inputs, by activating nicotinic cholinergic receptors (nAChR), have been suggested to counterbalance the noradrenergic input. Here we investigated whether adrenergic signaling regulates nAChR channels in rat pinealocytes. Acetylcholine or the selective nicotinic receptor agonist 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP) activated large nAChR currents in whole cell patch-clamp experiments. Norepinephrine (NE) reduced the nAChR currents, an effect partially mimicked by a β-adrenergic receptor agonist, isoproterenol, and blocked by a β-adrenergic receptor antagonist, propranolol. Increasing intracellular cAMP levels using membrane-permeable 8-bromoadenosine (8-Br)-cAMP or 5,6-dichlorobenzimidazole riboside-3′,5′-cyclic monophosphorothioate (cBIMPS) also reduced nAChR activity, mimicking the effects of NE and isoproterenol. Further, removal of ATP from the intracellular pipette solution blocked the reduction of nAChR currents, suggesting involvement of protein kinases. Indeed protein kinase A inhibitors, H-89 and Rp-cAMPS, blocked the modulation of nAChR by adrenergic stimulation. After the downmodulation by NE, nAChR channels mediated a smaller Ca2+ influx and less membrane depolarization from the resting potential. Together these results suggest that NE released from sympathetic terminals at night attenuates nicotinic cholinergic signaling. PMID:24553185

  2. Hypoxia increases exercise heart rate despite combined inhibition of β-adrenergic and muscarinic receptors

    DEFF Research Database (Denmark)

    Siebenmann, Christoph; Rasmussen, Peter; Sørensen, Henrik;

    2015-01-01

    Hypoxia increases the heart rate (HR) response to exercise but the mechanism(s) remain unclear. We tested the hypothesis that the tachycardic effect of hypoxia persists during separate but not combined inhibition of β-adrenergic and muscarinic receptors. Nine subjects performed incremental exerci...

  3. Cholesterol modulates the dimer interface of the β₂-adrenergic receptor via cholesterol occupancy sites.

    Science.gov (United States)

    Prasanna, Xavier; Chattopadhyay, Amitabha; Sengupta, Durba

    2014-03-18

    The β2-adrenergic receptor is an important member of the G-protein-coupled receptor (GPCR) superfamily, whose stability and function are modulated by membrane cholesterol. The recent high-resolution crystal structure of the β2-adrenergic receptor revealed the presence of possible cholesterol-binding sites in the receptor. However, the functional relevance of cholesterol binding to the receptor remains unexplored. We used MARTINI coarse-grained molecular-dynamics simulations to explore dimerization of the β2-adrenergic receptor in lipid bilayers containing cholesterol. A novel (to our knowledge) aspect of our results is that receptor dimerization is modulated by membrane cholesterol. We show that cholesterol binds to transmembrane helix IV, and cholesterol occupancy at this site restricts its involvement at the dimer interface. With increasing cholesterol concentration, an increased presence of transmembrane helices I and II, but a reduced presence of transmembrane helix IV, is observed at the dimer interface. To our knowledge, this study is one of the first to explore the correlation between cholesterol occupancy and GPCR organization. Our results indicate that dimer plasticity is relevant not just as an organizational principle but also as a subtle regulatory principle for GPCR function. We believe these results constitute an important step toward designing better drugs for GPCR dimer targets.

  4. Significance of adrenergic receptors for the development of nevus flammeus and nevus anemicus

    Energy Technology Data Exchange (ETDEWEB)

    Raff, M. (Vienna Univ. (Austria). 2. Hautklinik)

    1981-01-01

    Examination of patients with nevus flammeus or nevus anemicus showed disturbed sensibility in the area of the nevus in the majority of cases. Histologically and with special technique of histochemistry and fluorescence microscopy there was no evidence for neurogenic lesions. However, signs of vegetative disfunction were present: hyperhidrosis and absent reactivity of vasculature in the nevus area to vasoconstrictive and vasodilatatory stimuli. Based on these findings a disturbed regulation of vascular intramural adrenergic receptors seemed possible and really could be demonstrated by means of autoradiography. In both types of nevi only one of the adrenergic receptors could be marked with specific antagonists. Therefore, the persistent vascular dilatation and constriction can be accounted for by the absence of one of these receptors. This abnormal distribution of receptors could be due to a developmental defect influenced by the ''nerve growth factor''.

  5. 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.

  6. Tailoring therapy for heart failure: the pharmacogenomics of adrenergic receptor signaling

    Directory of Open Access Journals (Sweden)

    Femminella GD

    2014-09-01

    Full Text Available Grazia Daniela Femminella,1 Vincenzo Barrese,2,3 Nicola Ferrara,1,4 Giuseppe Rengo4 1Department of Translational Medical Sciences, Federico II University, Naples, Italy; 2Department of Neuroscience, Reproductive Science and Odontostomatology, Federico II University, Naples, Italy; 3Division of Biomedical Sciences, St George’s University of London, London, UK; 4”Salvatore Maugeri” Foundation – IRCCS – Scientific Institute of Telese Terme, Telese Terme, Benevento, Italy Abstract: Heart failure is one of the leading causes of mortality in Western countries, and β-blockers are a cornerstone of its treatment. However, the response to these drugs is variable among individuals, which might be explained, at least in part, by genetic differences. Pharmacogenomics is the study of genetic contributions to drug response variability in order to provide evidence for a tailored therapy in an individual patient. Several studies have investigated the pharmacogenomics of the adrenergic receptor system and its role in the context of the use of β-blockers in treating heart failure. In this review, we will focus on the most significant polymorphisms described in the literature involving adrenergic receptors and adrenergic receptor-related proteins, as well as genetic variations influencing β-blocker metabolism. Keywords: adrenergic system, polymorphisms, β-blockers, functional recovery

  7. Control of yeast mating signal transduction by a mammalian. beta. sub 2 -adrenergic receptor and G sub s. alpha. subunit

    Energy Technology Data Exchange (ETDEWEB)

    King, K.; Caron, M.G.; Lefkowitz, R.J. (Duke Univ. Medical Center, Durham, NC (USA)); Dohlman, H.G.; Thorner, J. (Univ. of California, Berkeley (USA))

    1990-10-05

    To facilitate functional and mechanistic studies of receptor-G protein interactions by expression of the human {beta}{sub 2}-adrenergic receptor (h{beta}-AR) has been expressed in Saccharomyces cerevisiae. This was achieved by placing a modified h{beta}-AR gene under control of the galactose-inducible GAL1 promoter. After induction by galactose, functional h{beta}-AR was expressed at a concentration several hundred times as great as that found in any human tissue. As determined from competitive ligand binding experiments, h{beta}-AR expressed in yeast displayed characteristic affinities, specificity, and stereoselectivity. Partial activation of the yeast pheromone response pathway by {beta}-adrenergic receptor agonists was achieved in cells coexpressing h{beta}-AR and a mammalian G protein (G{sub s}) {alpha} subunit - demonstrating that these components can couple to each other and to downstream effectors when expressed in yeast. This in vivo reconstitution system provides a new approach for examining ligand binding and G protein coupling to cell surface receptors.

  8. β2-Adrenergic receptor agonists activate CFTR in intestinal organoids and subjects with cystic fibrosis.

    Science.gov (United States)

    Vijftigschild, Lodewijk A W; Berkers, Gitte; Dekkers, Johanna F; Zomer-van Ommen, Domenique D; Matthes, Elizabeth; Kruisselbrink, Evelien; Vonk, Annelotte; Hensen, Chantal E; Heida-Michel, Sabine; Geerdink, Margot; Janssens, Hettie M; van de Graaf, Eduard A; Bronsveld, Inez; de Winter-de Groot, Karin M; Majoor, Christof J; Heijerman, Harry G M; de Jonge, Hugo R; Hanrahan, John W; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-09-01

    We hypothesized that people with cystic fibrosis (CF) who express CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations associated with residual function may benefit from G-protein coupled receptor (GPCR)-targeting drugs that can activate and enhance CFTR function.We used intestinal organoids to screen a GPCR-modulating compound library and identified β2-adrenergic receptor agonists as the most potent inducers of CFTR function.β2-Agonist-induced organoid swelling correlated with the CFTR genotype, and could be induced in homozygous CFTR-F508del organoids and highly differentiated primary CF airway epithelial cells after rescue of CFTR trafficking by small molecules. The in vivo response to treatment with an oral or inhaled β2-agonist (salbutamol) in CF patients with residual CFTR function was evaluated in a pilot study. 10 subjects with a R117H or A455E mutation were included and showed changes in the nasal potential difference measurement after treatment with oral salbutamol, including a significant improvement of the baseline potential difference of the nasal mucosa (+6.35 mV, pCFTR activation when administered ex vivo to organoids.This proof-of-concept study suggests that organoids can be used to identify drugs that activate CFTR function in vivo and to select route of administration.

  9. Quantitation of alpha 1-adrenergic receptors in porcine uterine and mesenteric arteries

    Energy Technology Data Exchange (ETDEWEB)

    Farley, D.B.; Ford, S.P.; Reynolds, L.P.; Bhatnagar, R.K.; Van Orden, D.E.

    1984-11-01

    The activation of vascular alpha-adrenergic receptors may be involved in the control of uterine blood flow. A radioligand binding assay with the use of the alpha 1-adrenergic antagonist /sup 3/H-WB-4101 was established to characterize the alpha-adrenergic receptors in uterine and mesenteric arterial membranes obtained from nonpregnant pigs. Specific binding of /sup 3/H-WB-4101 was rapid, saturable, and exhibited the alpha-adrenergic agonist potency order of (-)-epinephrine inhibition constant (Ki) . 0.6 mumol/L greater than (-)-norepinephrine (Ki . 1.5 mumol/L) much greater than (-)-isoproterenol (Ki . 120 mumol/L). The alpha-adrenergic antagonist phentolamine (Ki . 6.0 nmol/L) was 200 times more potent than the beta-adrenergic antagonist (+/-)-propranolol (Ki . 1,200 nmol/L); the alpha 1-selective antagonist prazosin (Ki . 1.2 nmol/L) was 130 times more potent than the alpha 2-selective antagonist yohimbine (Ki . 160 nmol/L). Scatchard analysis, as well as iterative curve-fitting analysis, demonstrated that /sup 3/H-WB-4101 binding by arterial membranes was to a single class of binding sites. Uterine arteries exhibited greater maximal binding capacity (BMax) than that of mesenteric arteries (47.5 +/- 3.2 versus 30.9 +/- 3.6 fmol per milligram of protein, p less than 0.01), but the uterine artery dissociation constant (Kd) was higher, thus indicating a lower affinity, when compared with mesenteric artery (0.43 +/- 0.04 versus 0.33 +/- 0.04 nmol/L, p less than 0.05).

  10. Characterization of beta-adrenergic receptors in dispersed rat testicular interstitial cells

    Energy Technology Data Exchange (ETDEWEB)

    Poyet, P.; Labrie, F.

    1987-01-01

    Recent studies have shown that beta-adrenergic agents stimulate steroidogenesis and cyclic AMP formation in mouse Leydig cells in culture. To obtain information about the possible presence and the characteristics of a beta-adrenergic receptor in rat testicular interstitial cells, the potent beta-adrenergic antagonist (/sup 125/I)cyanopindolol (CYP) was used as ligand. Interstitial cells prepared by collagenase dispersion from rat testis were incubated with the ligand for 2 h at room temperature. (/sup 125/I)cyanopindolol binds to a single class of high affinity sites at an apparent KD value of 15 pM. A number of sites of 6,600 sites/cell is measured when 0.1 microM (-) propranolol is used to determine non-specific binding. The order of potency of a series of agonists competing for (/sup 125/I)cyanopindolol binding is consistent with the interaction of a beta 2-subtype receptor: zinterol greater than (-) isoproterenol greater than (-) epinephrine = salbutamol much greater than (-) norepinephrine. In addition, it was observed that the potency of a large series of specific beta 1 and beta 2 synthetic compounds for displacing (/sup 125/I)cyanopindolol in rat interstitial cells is similar to the potency observed for these compounds in a typical beta 2-adrenergic tissue, the rat lung. For example, the potency of zinterol, a specific beta 2-adrenergic agonist, is 10 times higher in interstitial cells and lung than in rat heart, a typical beta 1-adrenergic tissue. Inversely, practolol, a typical beta 1-antagonist, is about 50 times more potent in rat heart than in interstitial cells and lung.

  11. Ghrelin secretion stimulated by β1-adrenergic receptors in cultured ghrelinoma cells and in fasted mice

    Science.gov (United States)

    Zhao, Tong-Jin; Sakata, Ichiro; Liang, Guosheng; Richardson, James A.; Brown, Michael S.; Goldstein, Joseph L.; Zigman, Jeffrey M.

    2010-01-01

    Ghrelin, an octanoylated peptide hormone produced in the stomach, rises dramatically in mouse plasma during chronic severe calorie deprivation, an event that is essential to maintain life. The mechanism for this increase is not understood. Here, we study the control of ghrelin secretion in tissue culture cells derived from mice bearing ghrelinomas induced by a tissue-specific SV40 T-antigen transgene. We found that the ghrelin-secreting cells express high levels of mRNA encoding β1-adrenergic receptors. Addition of norepinephrine or epinephrine to the culture medium stimulated ghrelin secretion, and this effect was blocked by atenolol, a selective β1-adrenergic antagonist. When WT mice were treated with reserpine to deplete adrenergic neurotransmitters from sympathetic neurons, the fasting-induced increase in plasma ghrelin was blocked. Inhibition was also seen following atenolol administration. We conclude that ghrelin secretion during fasting is induced by adrenergic agents released by sympathetic neurons and acting directly on β1 receptors on the ghrelin-secreting cells of the stomach. PMID:20713709

  12. Ghrelin secretion stimulated by {beta}1-adrenergic receptors in cultured ghrelinoma cells and in fasted mice.

    Science.gov (United States)

    Zhao, Tong-Jin; Sakata, Ichiro; Li, Robert Lin; Liang, Guosheng; Richardson, James A; Brown, Michael S; Goldstein, Joseph L; Zigman, Jeffrey M

    2010-09-07

    Ghrelin, an octanoylated peptide hormone produced in the stomach, rises dramatically in mouse plasma during chronic severe calorie deprivation, an event that is essential to maintain life. The mechanism for this increase is not understood. Here, we study the control of ghrelin secretion in tissue culture cells derived from mice bearing ghrelinomas induced by a tissue-specific SV40 T-antigen transgene. We found that the ghrelin-secreting cells express high levels of mRNA encoding beta(1)-adrenergic receptors. Addition of norepinephrine or epinephrine to the culture medium stimulated ghrelin secretion, and this effect was blocked by atenolol, a selective beta(1)-adrenergic antagonist. When WT mice were treated with reserpine to deplete adrenergic neurotransmitters from sympathetic neurons, the fasting-induced increase in plasma ghrelin was blocked. Inhibition was also seen following atenolol administration. We conclude that ghrelin secretion during fasting is induced by adrenergic agents released by sympathetic neurons and acting directly on beta(1) receptors on the ghrelin-secreting cells of the stomach.

  13. Alpha-adrenergic receptor blockade by phentolamine increases the efficacy of vasodilators in penile corpus cavernosum.

    Science.gov (United States)

    Kim, N N; Goldstein, I; Moreland, R B; Traish, A M

    2000-03-01

    Penile trabecular smooth muscle tone, a major determinant of erectile function, is highly regulated by numerous inter- and intracellular pathways. The interaction between pathways mediating contraction and relaxation has not been studied in detail. To this end, we investigated the functional effects of alpha adrenergic receptor blockade with phentolamine and its interaction with vasodilators (sildenafil, vasoactive intestinal polypeptide (VIP) and PGE1) that elevate cyclic nucleotides on penile cavernosal smooth muscle contractility. In organ bath preparations of cavernosal tissue strips contracted with phenylephrine, phentolamine significantly enhanced relaxation induced by sildenafil, VIP and PGE1. Sildenafil, VIP or PGE1 also significantly enhanced relaxation induced by phentolamine in cavernosal tissue strips contracted with phenylephrine. To study the effects of alpha adrenergic receptor blockade and modification of cyclic nucleotide metabolism during active neurogenic input, cavernosal tissue strips in organ bath preparations were contracted with the non-adrenergic agonist endothelin-1 and subjected to electrical field stimulation (EFS) in the absence or presence of phentolamine and/or sildenafil. EFS (5-40Hz) typically caused biphasic relaxation and contraction responses. Phentolamine alone enhanced relaxation and reduced or prevented contraction to EFS. Sildenafil enhanced relaxation to EFS at lower frequencies (phentolamine and sildenafil enhanced EFS-induced relaxation at all frequencies tested. EFS, in the presence of 10 nM phentolamine and 30 nM sildenafil, produced enhanced relaxation responses which were quantitatively similar to those obtained in the presence of 50 nM sildenafil alone. Thus, blockade of alpha-adrenergic receptors with phentolamine increases the efficacy of cyclic nucleotide-dependent vasodilators. Furthermore, phentolamine potentiates relaxation and attenuates contraction in response to endogenous neurotransmitters which are released

  14. Brain beta-adrenergic receptor binding in rats with obesity induced by a beef tallow diet.

    Science.gov (United States)

    Matsuo, T; Suzuki, M

    1997-01-01

    We have previously reported that compared with safflower oil diet, feeding a beef tallow diet leads to a greater accumulation of body fat by reducing sympathetic activities. The present study examined the effects of dietary fats consisting of different fatty acids on alpha1- and beta-adrenergic receptor binding in the hypothalamus and cerebral cortex. Male Sprague-Dawley rats were meal-fed isoenergetic diets based on safflower oil (rich in n-6 polyunsaturated fatty acids) or beef tallow (rich in saturated fatty acids) for 8 weeks. Binding affinities of the beta-adrenergic receptor in the hypothalamus and cortex were significantly lower in the beef tallow diet group, but those of the alpha1-receptor did not differ between the two groups. The polyunsaturated to saturated fatty acid (P/S) ratio and fluidities of plasma membranes in the hypothalamus and cortex were lower in the beef tallow diet group than in the safflower oil diet group. These results suggest that the beef tallow diet decreases membrane fluidity by altering the fatty acid composition of plasma membranes in the hypothalamus and cerebral cortex of rat. Consequently, beta-adrenergic receptor binding affinities in the brain were lower in rats fed the beef tallow diet than in rats fed the safflower oil diet. We recognized that there is possible link between the membrane fluidity and the changes in affinity of beta-adrenoceptors in rat brain.

  15. The thiazide-sensitive Na(+)-Cl(-) cotransporter gene, C1784T, and adrenergic receptor-beta3 gene, T727C, may be gene polymorphisms susceptible to the antihypertensive effect of thiazide diuretics.

    Science.gov (United States)

    Matayoshi, Tetsutaro; Kamide, Kei; Takiuchi, Shin; Yoshii, Masayoshi; Miwa, Yoshikazu; Takami, Yoichi; Tanaka, Chihiro; Banno, Mariko; Horio, Takeshi; Nakamura, Satoko; Nakahama, Hajime; Yoshihara, Fumiki; Inenaga, Takashi; Miyata, Toshiyuki; Kawano, Yuhei

    2004-11-01

    The response of blood pressure to thiazide diuretics (TZDs) differs among individuals. The prediction of the antihypertensive effect of TZDs is important for realizing individualized therapy in the management of hypertension. The aim of this study was to identify the single nucleotide polymorphisms (SNPs) susceptible to the antihypertensive effect of TZDs, particularly focusing on genes related to water-electrolyte absorption in the kidney. Seventy-six outpatients (mean age, 65.4+/-9.0 years) with essential hypertension (EHT) taking TZDs were retrospectively assessed. We defined as responders (R) those whose mean blood pressure was lowered by more than 5 mmHg after the use of TZDs. Forty-eight SNPs in 17 genes (ADD1, GNB3, TSC [SLC12A3], MLR [NR3C2], NCX1 [SLC8A1], WNK1, WNK4, AGT, ACE, AT1 [AGTR1], CYP11B2, ADRB1, ADRB2, ADRB3, ADRA1A, ADRA1B, ADRA2A) were genotyped in the 76 patients. The SNPs in TSC, MLR, NCX1, WNK1, and WNK4 were identified by direct sequencing and those with minor frequencies of greater than 5% were genotyped in this study. The comparison of polymorphism prevalence between R and non-responders (NR) showed significant differences in TSC C1784T (C allele vs. T allele, odds ratio (OR)=3.81, p =0.016, confidence interval (CI): 1.25-11.63) and ADRB3 T727C (Trp64Arg) (T allele vs. C allele, OR=4.59, p =0.005, CI: 1.54-13.68). The blood pressure (BP) in patients homozygous for the major alleles of both TSC C1784T and ADRB3 T727C were significantly reduced by TZD treatment; however, the BP in those homozygous for the minor allele and heterozygous (TSC C1784T: TT+CT; ADRB3 T727C: CC+CT) for both SNPs were not significantly changed after TZD treatment. Both newly detected TSC C1784T and ADRB3 T727C are gene polymorphisms susceptible to the antihypertensive effect of TZDs in patients with EHT. Thus, the prediction of BP reduction by TZDs may be possible by evaluating these two SNPs.

  16. Expression of hippocampal adrenergic receptor mRNA in a rat model of depression

    Institute of Scientific and Technical Information of China (English)

    Jianbin Zhang; Lingling Wang; Xinjun Wang; Jingfeng Jiang; Xiaoren Xiang; Tianjun Wang

    2011-01-01

    Adrenergic receptor dysfunction is suggested as a potential cause of hippocampal vulnerability to stress-related pathology. We examined mRNA expression of adrenergic receptor (AR) subtypes α1-AR, α2-AR, and β1-AR in hippocampal subregions (CA1, CA3, dentate gyrus) using in situ hybridization in a depression model induced by chronic unpredictable mild stress and social isolation. α1-AR mRNA expression was significantly increased in the CA3 and dentate gyrus, β1-AR mRNA was significantly increased in the CA1, and α2-AR mRNA remained unchanged in all regions of depression rats compared with controls. Thus, different AR subtypes exhibit a differing pattern of mRNA expression in various hippocampal subregions following depression.

  17. β2 Adrenergic receptor on T lymphocytes and its clinical implications

    Institute of Scientific and Technical Information of China (English)

    Xuelai Fan; Yuedan Wang

    2009-01-01

    Sustained complex cross-talk between the immune system and the nervous system plays a vital role in retaining homeostasis in a healthy individual.One of the central regulatory mechanisms involved is the existence and functions of β2-adrenergic receptors (β2AR) on T lymphocytes.This article reviews research progress made recently,including the expression of adrenergic receptors on Tlymphocytes,the structure and intracellular pathways of β2AR,the activation of I32AR by either endogenous or exogenous agonists,and the effect of β2AR stimulation on T cells which alters T cell proliferation,differentiation,cytokine production and T-helper-mediated antibody production.Furthermore,we discuss the roles of β2AR played in the pathogenesis and treatment of autoimmune diseases.

  18. α1A-adrenergic receptor mediated pressor response to phenylephrine in anesthetized rat

    Institute of Scientific and Technical Information of China (English)

    XU Qi; ZHU Weizhong; L(U) Zhizhen; ZHANG Youyi; HAN Qide

    2004-01-01

    To determine which subtype of α1A-adrenergic receptors plays a role in the regulation of blood pressure, with α1A-adrenergic receptor-mediated vasoconstriction in perfused hindlimb as a control, we compared the inhibitory effects of various α1A-adrenergic receptor selective antagonists on the vasopressure responses to phenylephrine between the mean arterial pressure and hindlimb perfusion pressure in anesthetized rats. In Normotensive Wistar rats, the results showed that the inhibitory effects (dose ratios of ED50, Dr) of α1A-adrenoceptor selective antagonist (prazosin, Dr 13.5 ± 3.6 vs.15.1 ± 4.3, n = 11), α1A-adrenoceptor selective antagonist (5- methyl-urapidil, Dr 2.4 ± 0.9 vs. 3.7 ± 2.3, n = 12; RS-17053, Dr 3.2 ± 1.6 vs. 4.4 ± 3.3, n =12) and α1D- adrenoceptor selective antagonist (BMY7378, Dr 1.9 ± 0.9 vs. 2.2 ± 0.8, n = 8) on phenylephrine- induced increases of perfusion pressure in the autoperfused femoral beds were the same as that in the mean arterial blood pressure in normotensive Wistar rats. The inhibitory effects of antagonists (RS-17053, Dr 3.4 ± 0.6 vs. 4.3 ± 0.9, n = 5; BMY7378, Dr 1.7±0.5 vs. 1.7 ± 0.5, n = 8) in spontaneous hypertensive rats were similar with the Wistar rats. These results suggest that the mean arterial pressure induced by phenylephrine was mainly mediated by α1A-adrenergic receptor in both the anesthetized Wistar rats and spontaneous hypertensive rats.

  19. Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptor-induced cardiomyocyte hypertrophy

    Institute of Scientific and Technical Information of China (English)

    Da-li LUO; Jian GAO; Xiao-mei LAN; Gang WANG; Sheng WEI; Rui-ping XIAO; Qi-de HAN

    2006-01-01

    Aim: Intracellular Ca2+ plays pivotal roles in diverse cellular functions, including gene transcription that underlies cardiac remodeling during stress responses. However, the role of inositol 1,4,5-trisphosphate receptors (IP3Rs) in the mediation of cardiac intracellular Ca2+ and hypertrophic growth remains elusive. Prior work with neonatal rat ventricular myocytes suggests that activation of IP3Rs may be linked to α1 adrenergic receptor (α1AR) increased stereotyped Ca2+ spark occurrence and global Ca2+ oscillations. Thus, we hypothesized that Ca2+ release through IP3Rs was necessary for α1AR-stimulated cardiac hypertrophy. Methods: We used myoinositol 1,4,5-trisphosphate hexakis (butyryloxymethyl) ester (IP3BM), a membrane-permeant ester of IP3, to activate IP3Rs directly, and Fluo 4/AM to measure intracellular Ca2+ signaling. Results: IP3BM (10μmol·L-1) mimicked the effects of phenylephrine, a selective agonist of α1AR, in increments in local Ca2+ spark release (especially in the perinuclear area) and global Ca2+ transient frequencies. More importantly, IP3R inhibitors, 2-aminoethoxydiphenyl borate and Xestospongin C, abolished the IP3BM-induced Ca2+ responses, and significantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cell size, [3H] leucine incorporation and atrial natriuretic factor gene expression, during sustained (48 h) phenylephrine stimulation. Conclusion: These results, therefore, provide cellular mechanisms that link IP3R signaling to α1AR-stimulated gene expression and cardiomyocyte hypertrophy.

  20. Alpha-Adrenergic receptors in cerebral microvessels of normotensive and spontaneously hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, H.; Wada, A.; Izumi, F.; Magnoni, M.S.; Trabucchi, M.

    1985-03-01

    In rat cerebral microvessels, we characterized alpha 1- and alpha 2-adrenergic receptors, using (/sup 3/H)prazosin and (/sup 3/H)-p-amino-clonidine as radioligands. (/sup 3/H)Prazosin binding to the cerebral microvessels was saturable and of high affinity (dissociation constant of 78 pM), with a maximum binding of 48 fmol/mg protein. (/sup 3/H)Prazosin binding reached equilibrium within 15 minutes and was dissociated by the addition of 10 microM phentolamine. The inhibitory effects of isomers of norepinephrine and epinephrine on the binding showed that l-isomers were over 10 times more potent than d-isomers. (/sup 3/H)-p-Amino-clonidine binding to the cerebral microvessels was saturable and of high affinity (K/sub D/ . 0.61 nM) with a B/sub max/ of 73 fmol/mg protein. The binding reached equilibrium within 30 minutes, and was dissociated by the addition of 100 microM l-norepinephrine. l-Isomers of norepinephrine and epinephrine were over 10 times more potent than d-isomers in displacing the binding. Thus, both (/sup 3/H)prazosin and (/sup 3/H)-p-amino-clonidine bindings to the cerebral microvessels were characterized by saturability, high affinity, reversibility, and stereo-specificity. Furthermore, the specificity of both binding sites was pharmacologically evaluated by the inhibitory effects of various adrenergic agonists and antagonists on the bindings. These data indicate the existence of alpha-adrenergic receptors in the cerebral microvessels and are consistent with the hypothesis that the cerebral microcirculation is regulated by adrenergic innervation. Furthermore, the receptors were measured in cerebral microvessels of spontaneously hypertensive rats and Wistar-Kyoto controls.

  1. The effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine, and antagonists yohimbine and efaroxan, on the spinal cholinergic receptor system in the rat

    DEFF Research Database (Denmark)

    Abelson, Klas S P; Höglund, A Urban

    2004-01-01

    Cholinergic agonists produce spinal antinociception via mechanisms involving an increased release of intraspinal acetylcholine. The cholinergic receptor system interacts with several other receptor types, such as alpha2-adrenergic receptors. To fully understand these interactions, the effects...... of various receptor ligands on the cholinergic system must be investigated in detail. This study was initiated to investigate the effects of the alpha2-adrenergic receptor agonists clonidine and rilmenidine and the alpha2-adrenergic receptor antagonists yohimbine and efaroxan on spinal cholinergic receptors...... in the rat. Spinal microdialysis was used to measure in vivo changes of acetylcholine after administration of the ligands, with or without nicotinic receptor blockade. In addition, in vitro binding properties of the ligands on muscarinic and nicotinic receptors were investigated. It was found that clonidine...

  2. 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.

  3. Recent advances in the molecular pharmacology of the alpha 1-adrenergic receptors.

    Science.gov (United States)

    Guarino, R D; Perez, D M; Piascik, M T

    1996-08-01

    This review is intended to discuss recent developments in the molecular pharmacology of the alpha 1-adrenergic receptor (alpha 1-AR) subtypes. After a brief historical development, we will focus on the more contemporary issues having to do with this receptor family. Emphasis will be put on recent data regarding the cloning, nomenclature, signalling mechanisms, and genomic organization of the alpha 1-AR subtypes. We will also highlight recent mutational studies that identify key amino acid residues involved in ligand binding, as well as the role of the alpha 1-AR subtypes in regulating physiologic processes.

  4. 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

    crystallization, we engineered a beta2AR fusion protein in which T4 lysozyme (T4L) replaces most of the third intracellular loop of the GPCR ("beta2AR-T4L") and showed that this protein retains near-native pharmacologic properties. Analysis of adrenergic receptor ligand-binding mutants within the context...... 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...

  5. Alpha adrenergic receptors in dog coronary arteries as detected with autoradiography

    Energy Technology Data Exchange (ETDEWEB)

    Muntz, K.; Calianos, T.; Buja, L.M.

    1986-03-05

    The authors used previously established methods to determine the presence of alpha adrenergic receptors in different sizes of dog coronary arteries using autoradiography of /sup 3/H-prazosin (PRAZ) and /sup 125/I-BE 2254 (HEAT) to label alpha/sub 1/ adrenergic receptors and /sup 3/H-rauwolscine (RAUW) to label alpha/sub 2/ adrenergic receptors. Frozen sections of the left main coronary artery (LMA), the left anterior descending artery (LAD) and myocardium were incubated in 3 concentrations of PRAZ (0.1, 0.5 and 1.0 nM) (n=5 dogs), 3 concentrations of RAUW (1, 3 and 5 nM) (n=5) and one concentration of HEAT (50 pM) (n=3). All incubations were done in the absence of (total binding) or presence of (nonspecific binding) 10/sup -5/ M phentolamine or yohimbine. The sections were processed for autoradiography and silver grains quantitated using an image analyzer. Analysis of variance determined that there was a significant difference between total and nonspecific binding in the LMA incubated with PRAZ (p < 0.016), but no significant difference between total and nonspecific binding in the LAD (p < 0.19) or in the arterioles (p < 0.68). In the experiments with HEAT, similar results were obtained. With RAUW, there was significant labeling of arterioles (p < 0.004), but not over the LAD (p < 0.11) or the LMA (p < 0.49). The results suggest that the number of coronary alpha/sub 1/ receptors decreases as vessel size decreases, while the number of alpha/sub 2/ receptors increases as vessel size decreases.

  6. Physical exercise, β-adrenergic receptors, and vascular response

    OpenAIRE

    Alexandre Sérgio Silva; Angelina Zanesco

    2010-01-01

    O exercício aeróbio promove efeitos benéficos na prevenção e tratamento de doenças como hipertensão arterial, aterosclerose, insuficiência venosa e doença arterial periférica. Os receptores β-adrenérgicos estão presentes em várias células. No sistema cardiovascular, promovem inotropismo e cronotropismo positivo cardíaco e relaxamento vascular. Embora os efeitos do exercício tenham sido investigados em receptores cardíacos, estudos focados nos vasos são escassos e controversos. Esta revis...

  7. An Alpha-1A Adrenergic Receptor Agonist Prevents Acute Doxorubicin Cardiomyopathy in Male Mice

    Science.gov (United States)

    Montgomery, Megan D.; Chan, Trevor; Swigart, Philip M.; Myagmar, Bat-erdene; Dash, Rajesh; Simpson, Paul C.

    2017-01-01

    Alpha-1 adrenergic receptors mediate adaptive effects in the heart and cardiac myocytes, and a myocyte survival pathway involving the alpha-1A receptor subtype and ERK activation exists in vitro. However, data in vivo are limited. Here we tested A61603 (N-[5-(4,5-dihydro-1H-imidazol-2-yl)-2-hydroxy-5,6,7,8-tetrahydronaphthalen-1-yl]methanesulfonamide), a selective imidazoline agonist for the alpha-1A. A61603 was the most potent alpha-1-agonist in activating ERK in neonatal rat ventricular myocytes. A61603 activated ERK in adult mouse ventricular myocytes and protected the cells from death caused by the anthracycline doxorubicin. A low dose of A61603 (10 ng/kg/d) activated ERK in the mouse heart in vivo, but did not change blood pressure. In male mice, concurrent subcutaneous A61603 infusion at 10 ng/kg/d for 7 days after a single intraperitoneal dose of doxorubicin (25 mg/kg) increased survival, improved cardiac function, heart rate, and cardiac output by echocardiography, and reduced cardiac cell necrosis and apoptosis and myocardial fibrosis. All protective effects were lost in alpha-1A-knockout mice. In female mice, doxorubicin at doses higher than in males (35–40 mg/kg) caused less cardiac toxicity than in males. We conclude that the alpha-1A-selective agonist A61603, via the alpha-1A adrenergic receptor, prevents doxorubicin cardiomyopathy in male mice, supporting the theory that alpha-1A adrenergic receptor agonists have potential as novel heart failure therapies. PMID:28081170

  8. A molecular dynamics approach to receptor mapping: application to the 5HT3 and beta 2-adrenergic receptors.

    Science.gov (United States)

    Gouldson, P R; Winn, P J; Reynolds, C A

    1995-09-29

    A molecular dynamics-based approach to receptor mapping is proposed, based on the method of Rizzi (Rizzi, J. P.; et al. J. Med. Chem. 1990, 33, 2721). In Rizzi's method, the interaction energy between a series of drug molecules and probe atoms (which mimic functional groups on the receptor, such as hydrogen bond donors) was calculated. These interactions were calculated on a three-dimensional grid within a molecular mechanics parameters, were placed at these minima. The distances between the dummy atom sites were monitored during molecular dynamics simulations and plotted as distance distribution functions. Important distances within the receptor became apparent, as drugs with a common mode of binding share similar peaks in the distance distribution functions. In the case of specific 5HT3 ligands, the important donor--acceptor distance within the receptor has a range of ca. 7.9--8.9 A. In the case of specific beta 2-adrenergic ligands, the important donor--acceptor distances within the receptor lie between ca. 7--9 A and between 8 and 10 A. These distances distribution functions were used to assess three different models of the beta 2-adrenergic G-protein-coupled receptor. The comparison of the distance distribution functions for the simulation with the actual donor--acceptor distances in the receptor models suggested that two of the three receptor models were much more consistent with the receptor-mapping studies. These receptor-mapping studies gave support for the use of rhodopsin, rather than the bacteriorhodopsin template, for modeling G-protein-coupled receptors but also sounded a warning that agreement with binding data from site-directed mutagenesis experiments does not necessarily validate a receptor model.

  9. Identification of alpha 2-adrenergic receptor sites in human retinoblastoma (Y-79) and neuroblastoma (SH-SY5Y) cells

    Energy Technology Data Exchange (ETDEWEB)

    Kazmi, S.M.; Mishra, R.K.

    1989-02-15

    The existence of specific alpha 2-adrenergic receptor sites has been shown in human retinoblastoma (Y-79) and neuroblastoma (SH-SH5Y) cells using direct radioligand binding. (/sup 3/H)Rauwolscine, a selective alpha 2-adrenergic receptor antagonist, exhibited high affinity, saturable binding to both Y-79 and SH-SY5Y cell membranes. The binding of alpha 1 specific antagonist, (/sup 3/H)Prazocine, was not detectable in either cell type. Competition studies with antagonists yielded pharmacological characteristics typical of alpha 2-adrenergic receptors: rauwolscine greater than yohimbine greater than phentolamine greater than prazocine. Based on the affinity constants of prazocine and oxymetazoline, it appears that Y-79 cells contain alpha 2A receptor, whereas SH-SY5Y cells probably represent a mixture of alpha 2A and alpha 2B receptors. alpha 2-agonists clonidine and (-)epinephrine inhibition curves yielded high and low affinity states of the receptor in SH-SY5Y cells. Gpp(NH)p and sodium ions reduced the proportion of high affinity sites of alpha 2 receptors. These two neuronal cell lines of human origin would prove useful in elucidating the action and regulation of human alpha 2-adrenergic receptors and their interaction with other receptor systems.

  10. 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......Previously metal-ion sites have been used as structural and functional probes in seven transmembrane receptors (7TM), but as yet all the engineered sites have been inactivating. Based on presumed agonist interaction points in transmembrane III (TM-III) and -VII of the beta(2)-adrenergic receptor......, in this paper we construct an activating metal-ion site between the amine-binding Asp-113 in TM-III-or a His residue introduced at this position-and a Cys residue substituted for Asn-312 in TM-VII. No increase in constitutive activity was observed in the mutant receptors. Signal transduction was activated...

  11. Changing face of β2-adrenergic and muscarinic receptor therapies in asthma.

    Science.gov (United States)

    Wasilewski, Nastasia V; Lougheed, M Diane; Fisher, John T

    2014-06-01

    Despite current available treatment options, a significant proportion of patients with asthma remain uncontrolled and asthma pharmacotherapy continues to evolve. β2-Adrenergic receptor agonists play a major role as bronchodilators in asthma therapy, although new perspectives reflect the potential for bias G-protein coupled receptor signaling pathways. Due to the success of muscarinic antagonists in chronic obstructive pulmonary disease, and the elucidation that muscarinic receptors play a role in airway remodeling, muscarinic receptors represent an attractive therapeutic target in asthma. Although short-acting muscarinic antagonists are currently limited to their use in acute asthma and as alternative bronchodilators in individuals who experience side effects with β2-agonists, recent clinical trials indicate that the long-acting muscarinic antagonist, tiotropium, deserves consideration as a potential therapeutic agent for select populations. The continued evolution of anticholinergic therapy in asthma will require appropriately designed studies to assess mechanisms, efficacy and safety in asthma.

  12. A comparison of adrenergic receptors of rat ascites hepatoma AH130 cells with those of normal rat hepatocytes.

    Science.gov (United States)

    Sanae, F; Miyamoto, K; Koshiura, R

    1988-04-01

    The pharmacological specificity of adrenergic receptors in the plasma membrane of rat ascites hepatoma AH130 cells was compared with that in normal rat hepatocytes. The number of [125I]iodocyanopindolol-binding sites was much greater in AH130 cells than in the hepatocytes. We characterized the alpha-adrenergic receptor subtypes using the alpha 1-selective ligand [3H]prazosin and the alpha 2-selective ligand [3H]clonidine. AH130 cells had fewer prazosin-binding sites than the hepatocytes and about 8 times as many clonidine-binding sites of high affinity. The results showed that the adrenergic receptors in AH130 cells have pharmacological properties that are very different from those of the receptors in normal rat hepatocytes.

  13. Signaling from beta1- and beta2-adrenergic receptors is defined by differential interactions with PDE4

    DEFF Research Database (Denmark)

    Richter, Wito; Day, Peter; Agrawal, Rani

    2008-01-01

    Beta1- and beta2-adrenergic receptors (betaARs) are highly homologous, yet they play clearly distinct roles in cardiac physiology and pathology. Myocyte contraction, for instance, is readily stimulated by beta1AR but not beta2AR signaling, and chronic stimulation of the two receptors has opposing...

  14. Effects and mechanism of different adrenergic receptor antagonists on left ventricular hypertrophy subsequent to coarctation of abdominal aorta in rats

    Institute of Scientific and Technical Information of China (English)

    HU Qin; LI Long-gui; ZHANG Yun

    2004-01-01

    To study the changes of a collagen-binding protein (Colligin) and myosin heavy chain isoform (α/β-MHC) gene and protein in left ventricular hypertrophy subsequent to coarctation of abdominal aorta in rats and the ef-fects of three kinds of adrenergic receptor blockers: Carvedilol (CAR), Metoprolol (MET) and Terazosin (TER) on these changes, and to elucidate the effects and new mechanism of CAR on left ventricular hypearophy regression. Methods: A model of hypertrophy induced by coarctation of abdominal aorta(CAA) was used in this study. Thirty two male istar rats were divided randomly into four groups 4 weeks after CAA operation: CAA, CAR, MET and TER.emodynamics, ventric-ular remodeling parameters, expressions of Colligin and α/β-MHC mRNA, protein expressions of Collagen Ⅰ /Ⅲ and Colligin were investigated in the four groups and sham operation group. Results: Left ventricle hypertrophy was observed clearly 16 weeks after operation. The ratio of α/β-MHC mRNA decreased, while expressions of Collagen Ⅰ/Ⅲ proteins and Colligin mRNA/protein increased( P < 0.05). CAR could ameliorate left ventricle hypertrophy prior to MET and TER. CAR could also change the expressions of α/β-MHC, Collagen Ⅰ/Ⅲ and Colligin in both gene and protein levels ( P < 0.05), while MET and TER have no effect on them ( P > 0.05). Conclusion: The effects of CAR on extracellular matrix proteins and MHC isoform shift regression of left ventricle may be due to antiproliferative or antioxidative mechanism, which was indepen-dent of beta-adrenergic receptor antagonist.

  15. Label-free integrative pharmacology on-target of drugs at the β2-adrenergic receptor

    Science.gov (United States)

    Ferrie, Ann M.; Sun, Haiyan; Fang, Ye

    2011-07-01

    We describe a label-free integrative pharmacology on-target (iPOT) method to assess the pharmacology of drugs at the β2-adrenergic receptor. This method combines dynamic mass redistribution (DMR) assays using an array of probe molecule-hijacked cells with similarity analysis. The whole cell DMR assays track cell system-based, ligand-directed, and kinetics-dependent biased activities of the drugs, and translates their on-target pharmacology into numerical descriptors which are subject to similarity analysis. We demonstrate that the approach establishes an effective link between the label-free pharmacology and in vivo therapeutic indications of drugs.

  16. Cholesterol increases kinetic, energetic, and mechanical stability of the human β2-adrenergic receptor

    DEFF Research Database (Denmark)

    Zocher, Michael; Zhang, Cheng; Rasmussen, Søren Gøgsig Faarup;

    2012-01-01

    the kinetic, energetic, and mechanical stability of almost every structural segment at sufficient magnitude to alter the structure and functional relationship of β(2)AR. One exception was the structural core segment of β(2)AR, which establishes multiple ligand binding sites, and its properties were...... to quantify the mechanical strength and flexibility, conformational variability, and kinetic and energetic stability of structural segments stabilizing the human β(2)-adrenergic receptor (β(2)AR) in the absence and presence of the cholesterol analog cholesteryl hemisuccinate (CHS). CHS considerably increased...

  17. Altered beta-adrenergic receptor-stimulated cAMP formation in cultured skin fibroblasts from Alzheimer donors.

    Science.gov (United States)

    Huang, H M; Gibson, G E

    1993-07-15

    An alteration in signal transduction systems in Alzheimer's disease would likely be of pathophysiological significance, because these steps are critical to normal brain function. Since dynamic processes are difficult to study in autopsied brain, the current studies utilized cultured skin fibroblasts. The beta-adrenergic-stimulated increase in cAMP was reduced approximately 80% in fibroblasts from Alzheimer's disease compared with age-matched controls. The deficit in Alzheimer fibroblasts in response to various adrenergic agonists paralleled their beta-adrenergic potency, and enhancement of cAMP accumulation by a non-adrenergic agonist, such as prostaglandin E1, was similar in Alzheimer and control fibroblasts. Diminished adenylate cyclase activity did not underlie these abnormalities, since direct stimulation of adenylate cyclase by forskolin elevated cAMP production equally in Alzheimer and control fibroblasts. Cholera toxin equally stimulated cAMP formation in Alzheimer and control fibroblasts. Moreover, cholera toxin partially reduced isoproterenol-induced cAMP deficit in Alzheimer fibroblasts. Pertussis toxin, on the other hand, did not alter the Alzheimer deficits. The results suggest either that the coupling of the GTP-binding protein(s) to the beta-adrenergic receptor is abnormal or that the sensitivity of receptor is altered with Alzheimer's disease. Further, any hypothesis about Alzheimer's disease must explain why a reduced beta-adrenergic-stimulated cAMP formation persists in tissue culture.

  18. β-Adrenergic receptor agonist increases voltage-gated Na(+) currents in medial prefrontal cortex pyramidal neurons.

    Science.gov (United States)

    Szulczyk, Bartlomiej

    2015-05-19

    The prefrontal cortex does not function properly in neuropsychiatric diseases and during chronic stress. The aim of this study was to test the effects of isoproterenol, a β-adrenergic receptor agonist, on the voltage-dependent fast-inactivating Na(+) currents in medial prefrontal cortex (mPFC) pyramidal neurons obtained from young rats. The recordings were performed in the cell-attached configuration. Isoproterenol (2μM) did not change the peak Na(+) current amplitude but shifted the IV curve of the Na(+) currents toward hyperpolarization. Pretreatment of the cells with the β-adrenergic antagonists propranolol and metoprolol abolished the effect of isoproterenol on the Na(+) currents, suggesting the involvement of β1-adrenergic receptors. The effect of β-adrenergic receptor stimulation on the sodium currents was dependent on kinase A and kinase C; the effect was diminished in the presence of the kinase A antagonist H-89 and the kinase C antagonist chelerythrine and abolished when the antagonists were coapplied. Moreover, isoproterenol depolarized the membrane potential recorded using the perforated-patch method, and this depolarization was abolished by cesium ions. Thus, in mPFC pyramidal neurons, stimulation of β-adrenergic receptors up-regulates the fast-inactivating voltage-gated Na(+) currents evoked by suprathreshold depolarizations.

  19. 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...

  20. Changes in number of alpha-adrenergic receptor subtypes in hepatocytes from rats fed 3'-methyl-4-dimethylaminoazobenzene.

    Science.gov (United States)

    Miyamoto, K; Sanae, F; Kohei, K; Nomura, M; Koshiura, R

    1990-01-01

    Changes in numbers of alpha 1- and alpha 2-adrenergic receptors in the plasma membranes of hepatocytes from female Donryu rats given feed containing 0.06% of the carcinogen 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB), were examined. alpha 1-Adrenergic receptors, measured in terms of [3H]prazosin binding, decreased to half of the control 2 weeks after the start of this diet, then gradually decreased for the next 22 weeks. alpha 2-Adrenergic receptors, measured in terms of [3H]clonidine binding, transiently increased 3-fold over the control at 2 weeks. These changes in the early period of the 3'-MeDAB diet intake may be related to hepatocarcinogenesis.

  1. The role of basolateral amygdala adrenergic receptors in hippocampus dependent spatial memory in rat

    Directory of Open Access Journals (Sweden)

    Vafaei A.L.

    2008-03-01

    Full Text Available Background and the purpose of the study: There are extensive evidences indicating that the noradrenergic system of the basolateral nucleus of the amygdala (BLA is involved in memory processes. The present study investigated the role of the BLA adrenergic receptors (ARs in hippocampus dependent spatial memory in place avoidance task in male rat. Material and Methods: Long Evans rats (n=150 were trained to avoid footshock in a 60° segment while foraging for scattered food on a circular (80-cm diameter arena. The rats were injected bilaterally in the BLA specific ARS (Adrenergic receptors agonist norepinephrine (NE, 0.5 and 1 µg/µl and specific β-ARs antagonist propranolol (PRO, 0.5 and 1 µg/µl before acquisition, after training or before retrieval of the place avoidance task. Control rats received vehicle at the same volume. The learning in a single 30-min session was assessed 24h later by a 30-min extinction trial in which the time to first entrance and the number of entrances to the shocked area measured the avoidance memory. Results: Acquisition and consolidation were enhanced and impaired significantly by NE and PRO when the drugs were injected 10 min before or immediately after training, respectively. In contrast, neither NE nor PRO influenced animal performances when injected before retention testing. Conclusion: Findings of this study indicates that adrenergic system of the BLA plays an important role in regulation of memory storage and show further evidences for the opinion that the BLA plays an important role in integrating hormonal and neurotransmitter influences on memory storage.

  2. Circadian-related heteromerization of adrenergic and dopamine D₄ receptors modulates melatonin synthesis and release in the pineal gland.

    Directory of Open Access Journals (Sweden)

    Sergio González

    Full Text Available The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenergic and dopamine D₄ receptors. Through α(₁B-D₄ and β₁-D₄ receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands. This inhibition was not observed at hours of the day when D₄ was not expressed. These data provide a new perspective on dopamine function and constitute the first example of a circadian-controlled receptor heteromer. The unanticipated heteromerization between adrenergic and dopamine D₄ receptors provides a feedback mechanism for the neuronal hormone system in the form of dopamine to control circadian inputs.

  3. -Adrenergic receptors on rat ventricular myocytes: characteristics and linkage to cAMP metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Buxton, I.L.O.; Brunton, L.L.

    1986-08-01

    When incubated with purified cardiomyocytes from adult rat ventricle, the 1-antagonist (TH)prazosin binds to a single class of sites with high affinity. Competition for (TH)prazosin binding by the 2-selective antagonist yohimbine and the nonselective -antagonist phentolamine demonstrates that these receptors are of the 1-subtype. In addition, incubation of myocyte membranes with (TH)yohimbine results in no measurable specific binding. Agonist competition for (TH)prazosin binding to membranes prepared from purified myocytes demonstrates the presence of two components of binding: 28% of 1-receptors interact with norepinephrine with high affinity (K/sub D/ = 36 nM), whereas the majority of receptors (72%) have a low affinity for agonist (K/sub D/ = 2.2 M). After addition of 10 M GTP, norepinephrine competes for (TH)prazosin binding to a single class of sites with lower affinity (K/sub D/ = 2.2 M). Incubation of intact myocytes for 2 min with 1 M norepinephrine leads to significantly less cyclic AMP (cAMP) accumulation than stimulation with either norepinephrine plus prazosin or isoproterenol. Likewise, incubation of intact myocytes with 10 W M norepinephrine leads to significantly less activation of cAMP-dependent protein kinase than when myocytes are stimulated by both norepinephrine and the 1-adrenergic antagonist, prazosin or the US -adrenergic agonist, isoproterenol. They conclude that the cardiomyocyte 1 receptor is coupled to a guanine nucleotide-binding protein, that 1-receptors are functionally linked to decreased intracellular cAMP content, and that this change in cellular cAMP is expressed as described activation of cAMP-dependent protein kinase.

  4. Long-acting β2-adrenergic receptor agonist in pediatric asthma

    Directory of Open Access Journals (Sweden)

    Shigemi Yoshihara

    2004-01-01

    Full Text Available Long-acting β2-adrenergic receptor agonists (LABA, a class of agents for the long-term management of childhood bronchial asthma, are recommended for use in combination with steroid inhalation for the treatment of the morning dip in severe childhood asthma. In the present review, salmeterol (SM, a LABA inhalant with a long-acting bronchodilator effect, was compared with the recently introduced tulobuterol patch (TBP in terms of safety and efficacy, based on their respective clinical effects on childhood asthma. From a clinical perspective, both drugs had a preventive effect by suppressing the morning dip and exercise-induced asthma when used concomitantly with an inhaled corticosteroid, and both agents were associated with a lower incidence of adverse effects on the cardiovascular system than oral β2-adrenergic receptor agonists. Based on these findings, both SM and TBP are concluded to be highly efficacious and safe bronchodilator agents that are appropriate for the long-term management of childhood asthma.

  5. 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.

  6. Alpha-1 adrenergic receptors gate rapid orientation-specific reduction in visual discrimination.

    Science.gov (United States)

    Treviño, Mario; Frey, Sebastian; Köhr, Georg

    2012-11-01

    Prolonged imbalance in sensory experience leads to dramatic readjustments in cortical representation. Neuromodulatory systems play a critical role in habilitating experience-induced plasticity and regulate memory processes in vivo. Here, we show that a brief period of intense patterned visual stimulation combined with systemic activation of alpha-1 adrenergic neuromodulator receptors (α(1)-ARs) leads to a rapid, reversible, and NMDAR-dependent depression of AMPAR-mediated transmission from ascending inputs to layer II/III pyramidal cells in the visual cortex of young and adult mice. The magnitude of this form of α(1)-AR long-term depression (LTD), measured ex vivo with miniature EPSC recordings, is graded by the number of orientations used during visual experience. Moreover, behavioral tests of visual function following the induction of α(1)-AR LTD reveal that discrimination accuracy of sinusoidal drifting gratings is selectively reduced at high spatial frequencies in a reversible, orientation-specific, and NMDAR-dependent manner. Thus, α(1)-ARs enable rapid cortical synaptic depression which correlates with an orientation-specific decrease in visual discrimination. These findings contribute to our understanding of how adrenergic receptors interact with neuronal networks in response to changes in active sensory experience to produce adaptive behavior.

  7. Astrocytic β2-adrenergic receptors mediate hippocampal long-term memory consolidation

    KAUST Repository

    Gao, Virginia

    2016-07-12

    Emotionally relevant experiences form strong and long-lasting memories by critically engaging the stress hormone/neurotransmitter noradrenaline, which mediates and modulates the consolidation of these memories. Noradrenaline acts through adrenergic receptors (ARs), of which β2- Adrenergic receptors (βARs) are of particular importance. The differential anatomical and cellular distribution of βAR subtypes in the brain suggests that they play distinct roles in memory processing, although much about their specific contributions and mechanisms of action remains to be understood. Here we show that astrocytic rather than neuronal β2ARs in the hippocampus play a key role in the consolidation of a fear-based contextual memory. These hippocampal β2ARs, but not β1ARs, are coupled to the training-dependent release of lactate from astrocytes, which is necessary for long- Term memory formation and for underlying molecular changes. This key metabolic role of astrocytic β2ARs may represent a novel target mechanism for stress-related psychopathologies and neurodegeneration.

  8. 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.

  9. Stimulation of postsynapse adrenergic α2A receptor improves attention/cognition performance in an animal model of attention deficit hyperactivity disorder.

    Science.gov (United States)

    Kawaura, Kazuaki; Karasawa, Jun-ichi; Chaki, Shigeyuki; Hikichi, Hirohiko

    2014-08-15

    A 5-trial inhibitory avoidance test using spontaneously hypertensive rat (SHR) pups has been used as an animal model of attention deficit hyperactivity disorder (ADHD). However, the roles of noradrenergic systems, which are involved in the pathophysiology of ADHD, have not been investigated in this model. In the present study, the effects of adrenergic α2 receptor stimulation, which has been an effective treatment for ADHD, on attention/cognition performance were investigated in this model. Moreover, neuronal mechanisms mediated through adrenergic α2 receptors were investigated. We evaluated the effects of both clonidine, a non-selective adrenergic α2 receptor agonist, and guanfacine, a selective adrenergic α2A receptor agonist, using a 5-trial inhibitory avoidance test with SHR pups. Juvenile SHR exhibited a shorter transfer latency, compared with juvenile Wistar Kyoto (WKY) rats. Both clonidine and guanfacine significantly prolonged the transfer latency of juvenile SHR. The effects of clonidine and guanfacine were significantly blocked by pretreatment with an adrenergic α2A receptor antagonist. In contrast, the effect of clonidine was not attenuated by pretreatment with an adrenergic α2B receptor antagonist, or an adrenergic α2C receptor antagonist, while it was attenuated by a non-selective adrenergic α2 receptor antagonist. Furthermore, the effects of neither clonidine nor guanfacine were blocked by pretreatment with a selective noradrenergic neurotoxin. These results suggest that the stimulation of the adrenergic α2A receptor improves the attention/cognition performance of juvenile SHR in the 5-trial inhibitory avoidance test and that postsynaptic, rather than presynaptic, adrenergic α2A receptor is involved in this effect.

  10. Trafficking of α1B-adrenergic receptor mediated by inverse agonist in living cells

    Institute of Scientific and Technical Information of China (English)

    MingXU; Ying-huaGUAN; NingXU; Zhang-yiLIANG; Shu-yiWang; YaoSONG; Chi-deHAN; Xin-shengZHAO; You-yiZHANG

    2005-01-01

    AIM The project is aimed at understanding the action of inverse agonist at single molecule level and capturing the real time picture of molecular behavior of α1B-adrenergic receptor (AR) mediated by inverse agonist in living cells by single molecule detection (SMD). METHODS The location and distribution of α1B-AR was detected by laser confocal and whole cell 3H-prazosin binding assay. Dynamic imaging of BODIPY-FL-labeled prazosin (Praz), specific antagonist of (1-AR, was observed in α1B-AR stably expressed human embryonic kidney 293 (HEK293) living cells. The detection of real-time dynamic behaviors of AR was achieved by using fluorescence-labeled AR and its ligand combined with SMD techniques. RESULTS α1B-AR was predominantly distributed on the cell surface and 8.2% of the total receptors were located in cytosol.

  11. Adrenergic receptor polymorphisms and autonomic nervous system function in human obesity.

    Science.gov (United States)

    Yasuda, Koichiro; Matsunaga, Tetsuro; Adachi, Tetsuya; Aoki, Norihiko; Tsujimoto, Gozoh; Tsuda, Kinsuke

    2006-09-01

    Adrenergic receptors (ARs) are cell-surface G-protein-coupled receptors for catecholamines. They are essential components of the sympathetic nervous system, organized within the autonomic nervous system (ANS), which controls various physiological functions, including energy homeostasis and metabolism of glucose and lipids. An impairment of ANS function in metabolism is considered to be one of the pathological states associated with human obesity and related metabolic diseases; thus, alterations in AR function might be implicated in the pathophysiology of these diseases. Several studies have suggested an association between obesity phenotypes and some AR polymorphisms. In vitro and human clinical studies indicate that some of these polymorphisms have functional and pathophysiological significance, including the linkage to ANS function. This review summarizes present knowledge of AR polymorphisms related to human obesity, and their association with ANS function.

  12. Stress-induced decrease of uterine blood flow in sheep is mediated by alpha 1-adrenergic receptors.

    Science.gov (United States)

    Dreiling, Michelle; Bischoff, Sabine; Schiffner, Rene; Rupprecht, Sven; Kiehntopf, Michael; Schubert, Harald; Witte, Otto W; Nathanielsz, Peter W; Schwab, Matthias; Rakers, Florian

    2016-09-01

    Prenatal maternal stress can be transferred to the fetus via a catecholamine-dependent decrease of uterine blood flow (UBF). However, it is unclear which group of adrenergic receptors mediates this mechanism of maternal-fetal stress transfer. We hypothesized that in sheep, alpha 1-adrenergic receptors may play a key role in catecholamine mediated UBF decrease, as these receptors are mainly involved in peripheral vasoconstriction and are present in significant number in the uterine vasculature. After chronic instrumentation at 125 ± 1 days of gestation (dGA; term 150 dGA), nine pregnant sheep were exposed at 130 ± 1 dGA to acute isolation stress for one hour without visual, tactile, or auditory contact with their flockmates. UBF, blood pressure (BP), heart rate (HR), stress hormones, and blood gases were determined before and during this isolation challenge. Twenty-four hours later, experiments were repeated during alpha 1-adrenergic receptor blockage induced by a continuous intravenous infusion of urapidil. In both experiments, ewes reacted to isolation with an increase in serum norepinephrine, cortisol, BP, and HR as typical signs of activation of sympatho-adrenal and the hypothalamic-pituitary-adrenal axis. Stress-induced UBF decrease was prevented by alpha 1-adrenergic receptor blockage. We conclude that UBF decrease induced by maternal stress in sheep is mediated by alpha 1-adrenergic receptors. Future studies investigating prevention strategies of impact of prenatal maternal stress on fetal health should consider selective blockage of alpha 1-receptors to interrupt maternal-fetal stress transfer mediated by utero-placental malperfusion.

  13. β2-Adrenergic ion-channel coupled receptors as conformational motion detectors.

    Directory of Open Access Journals (Sweden)

    Lydia N Caro

    Full Text Available Ion Channel-Coupled Receptors (ICCRs are artificial proteins comprised of a G protein-coupled receptor and a fused ion channel, engineered to couple channel gating to ligand binding. These novel biological objects have potential use in drug screening and functional characterization, in addition to providing new tools in the synthetic biology repertoire as synthetic K(+-selective ligand-gated channels. The ICCR concept was previously validated with fusion proteins between the K(+ channel Kir6.2 and muscarinic M(2 or dopaminergic D(2 receptors. Here, we extend the concept to the distinct, longer β(2-adrenergic receptor which, unlike M(2 and D(2 receptors, displayed barely detectable surface expression in our Xenopus oocyte expression system and did not couple to Kir6.2 when unmodified. Here, we show that a Kir6.2-binding protein, the N-terminal transmembrane domain of the sulfonylurea receptor, can greatly increase plasma membrane expression of β(2 constructs. We then demonstrate how engineering of both receptor and channel can produce β(2-Kir6.2 ICCRs. Specifically, removal of 62-72 residues from the cytoplasmic C-terminus of the receptor was required to enable coupling, suggesting that ligand-dependent conformational changes do not efficiently propagate to the distal C-terminus. Characterization of the β(2 ICCRs demonstrated that full and partial agonists had the same coupling efficacy, that an inverse agonist had no effect and that the stabilizing mutation E122 W reduced agonist-induced coupling efficacy without affecting affinity. Because the ICCRs are expected to report motions of the receptor C-terminus, these results provide novel insights into the conformational dynamics of the β(2 receptor.

  14. Alpha adrenergic receptor mediation of cardiovascular and metabolic responses to alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Brackett, D.J.; Gauvin, D.V.; Lerner, M.R.; Holloway, F.H.; Wilson, M.F. (Univ. of Oklahoma, Oklahoma City (United States) Veterans Affairs Medical Center, Oklahoma City, OK (United States))

    1992-02-26

    The role of alpha adrenergic receptors in acute cardiovascular and metabolic responses to alcohol (ETOH) have not been clearly defined. In this study two groups of male Sprague-Dawley rats were given intravenous phentolamine mesylate or saline prior to intragastric alcohol to blockade of alpha receptors during alcohol intoxication in conscious rats. ETOH alone evoked an increase in systemic vascular resistance (SVR), heart rate (HR), and blood glucose concentrations (G) and a decrease in mean arterial pressure (MAP), cardiac output (CO), central venous pressure (CVP), respiration rate (RR) and cardiac stroke volume (SV). Blood alcohol concentration (BAC) peaked at 30 min and remained elevated for the four hrs of monitoring. Phentolamine pretreatment produced a decrease in MAP and SV and an increase in HR. However, antagonism of the alpha receptor blocked the decrease in CO and the increase in SVR and G. The decrease in CVP was unaffected. Surprisingly, the early rise and peak in BAC in the phentolamine treated group was attenuated, but was the same as the untreated group during the final 3 hrs. These data suggest that alpha receptors are significant mediators of cardiovascular and glucoregulatory responses elicited by alcohol. Furthermore, alpha receptor blockade appears to effect the absorption and/or distribution of intragastrically administered alcohol.

  15. Divergent Label-free Cell Phenotypic Pharmacology of Ligands at the Overexpressed β2-Adrenergic Receptors

    Science.gov (United States)

    Ferrie, Ann M.; Sun, Haiyan; Zaytseva, Natalya; Fang, Ye

    2014-01-01

    We present subclone sensitive cell phenotypic pharmacology of ligands at the β2-adrenergic receptor (β2-AR) stably expressed in HEK-293 cells. The parental cell line was transfected with green fluorescent protein (GFP)-tagged β2-AR. Four stable subclones were established and used to profile a library of sixty-nine AR ligands. Dynamic mass redistribution (DMR) profiling resulted in a pharmacological activity map suggesting that HEK293 endogenously expresses functional Gi-coupled α2-AR and Gs-coupled β2-AR, and the label-free cell phenotypic activity of AR ligands are subclone dependent. Pathway deconvolution revealed that the DMR of epinephrine is originated mostly from the remodeling of actin microfilaments and adhesion complexes, to less extent from the microtubule networks and receptor trafficking, and certain agonists displayed different efficacy towards the cAMP-Epac pathway. We demonstrate that receptor signaling and ligand pharmacology is sensitive to the receptor expression level, and the organization of the receptor and its signaling circuitry.

  16. 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

  17. 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

  18. Heterocyclic acetamide and benzamide derivatives as potent and selective beta3-adrenergic receptor agonists with improved rodent pharmacokinetic profiles.

    Science.gov (United States)

    Goble, Stephen D; Wang, Liping; Howell, K Lulu; Bansal, Alka; Berger, Richard; Brockunier, Linda; DiSalvo, Jerry; Feighner, Scott; Harper, Bart; He, Jiafang; Hurley, Amanda; Hreniuk, Donna; Parmee, Emma; Robbins, Michael; Salituro, Gino; Sanfiz, Anthony; Streckfuss, Eric; Watkins, Eloisa; Weber, Ann E; Struthers, Mary; Edmondson, Scott D

    2010-03-15

    A series of amide derived beta(3)-adrenergic receptor (AR) agonists is described. The discovery and optimization of several series of compounds derived from 1, is used to lay the SAR foundation for second generation beta(3)-AR agonists for the treatment of overactive bladder.

  19. Involvement of β3-adrenergic receptors in the control of food intake in rats

    Directory of Open Access Journals (Sweden)

    S.A. Kanzler

    2011-11-01

    Full Text Available This study examined the food intake changes evoked by intracerebroventricular (icv injection of a selective agonist (BRL37344, 2 and 20 nmol or antagonist (SR59230A, 10 and 50 nmol of β3-adrenergic receptors in 24-h fasted rats (adult male Wistar rats, 200-350 g, N = 6/treatment. The animals were also pretreated with saline icv (SAL or SR59230A (50 nmol followed by BRL37344 (20 nmol or SAL in order to determine the selectivity of the effects evoked by BRL37344 on food intake or the selectivity of the effects evoked by SR59230A on risk assessment (RA behavior. The highest dose of BRL37344 (N = 7 decreased food intake 1 h after the treatment (6.4 ± 0.5 g in SAL-treated vs 4.2 ± 0.8 g in drug-treated rats. While both doses of SR59230A failed to affect food intake (5.1 ± 1.1 g for 10 nmol and 6.0 ± 1.8 g for 50 nmol, this treatment reduced the RA frequency (number/30 min (4 ± 2 for SAL-treated vs 1 ± 1 for 10 nmol and 0.5 ± 1 for 50 nmol SR59230A-treated rats, an ethological parameter related to anxiety. While pretreatment with SR59230A (7.0 ± 0.5 g abolished the hypophagia induced by BRL37344 (3.6 ± 0.9 g, BRL37344 suppressed the reduction in RA frequency caused by SR59230A. These results show that the hypophagia caused by BRL37344 is selectively mediated by β3-adrenergic receptors within the central nervous system. Moreover, they suggest the involvement of these receptors in the control of anxiety.

  20. Alpha/sub 2/-adrenergic receptors on a platelet precursor cell line, HEL

    Energy Technology Data Exchange (ETDEWEB)

    McKernan, R.M.; Motulsky, H.J.; Rozansky, D.; Insel, P.A.

    1986-03-01

    The authors have identified ..cap alpha../sub 2/-adrenergic receptors on human erythroleukemia HEL cells, a suspension-growing, bone-marrow-derived cell line related to human platelets. Intact HEL cells were studied using radioligand binding and cAMP accumulation assays. The authors identified saturable specific binding of the ..cap alpha../sub 2/-antagonist (/sup 3/H)yohimbine (yoh) in cells incubated at 37/sup 0/C for 1 hr (B/sub max/ 5900 +/- 2100 sites/cell, K/sub d/ 3.6 +/- 0.9 nM, n = 7). Competition for (/sup 3/H)yoh binding sites with antagonists confirmed that these sites were similar to human ..cap alpha../sub 2/-adrenoceptors from platelets and other resources, as typified by their high affinity for WY-26392, yohimbine and idazoxan, and very low affinity for prazosin. Studies at 37/sup 0/C revealed a low affinity of these sites for catecholamines (K/sub i/ for (-)-epinephrine, 21 ..mu..M; (-)-norepinephrine, 45 ..mu..M, (+)-epinephrine, 80 ..mu..M). When experiments were conducted at 4 /sup 0/C, (-)-epinephrine was able to compete for only 50-60% of the sites specifically labelled by (/sup 3/H)yoh at 37/sup 0/, but (-)-epinephrine had an approximately 10-fold greater affinity for these sites (K/sub i/ at 4 /sup 0/C = 2.4 ..mu..M). In addition, epinephrine inhibited cAMP accumulation stimulated by forskolin and PGE/sub 1/ in HEL cells; this response was inhibited by pertussis toxin. The authors conclude that HEL cells possess ..cap alpha../sub 2/-adrenergic receptors linked to G/sub i/ and thus should serve as a useful model to explore metabolism and regulation of these receptors in human cells.

  1. Effect of adrenergic receptor ligands on metaiodobenzylguanidine uptake and storage in neuroblastoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Babich, J.W. [Division of Nuclear Medicine, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States)]|[Department of Radiology, Harvard Medical School, Boston, Massachusetts (United States); Graham, W. [Division of Nuclear Medicine, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States); Fischman, A.J. [Division of Nuclear Medicine, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts (United States)]|[Department of Radiology, Harvard Medical School, Boston, Massachusetts (United States)

    1997-05-01

    The effects of adrenergic receptor ligands on uptake and storage of the radiopharmaceutical [{sup 125}I]metaiodobenzylguanidine (MIBG) were studied in the human neuroblastoma cell line SK-N-SH. For uptake studies, cells were with varying concentrations of {alpha}-agonist (clonidine, methoxamine, and xylazine), {alpha}-antagonist (phentolamine, tolazoline, phenoxybenzamine, yohimbine, and prazosin), {beta}-antagonist (propranolol, atenolol), {beta}-agonist (isoprenaline and salbutamol), mixed {alpha}/{beta} antagonist (labetalol), or the neuronal blocking agent guanethidine, prior to the addition of [{sup 125}I]MIBG (0.1 {mu}M). The incubation was continued for 2 h and specific cell-associated radioactivity was measured. For the storage studies, cells were incubated with [{sup 125}I]MIBG for 2 h, followed by replacement with fresh medium with or without drug (MIBG, clonidine, or yohimbine). Cell-associated radioactivity was measured at various times over the next 20 h. Propanolol reduced [{sup 125}I]MIBG uptake by approximately 30% (P<0.01) at all concentrations tested, most likely due to nonspecific membrane changes. In conclusion, the results of this study establish that selected adrenergic ligands can significantly influence the pattern of uptake and storage of MIBG in cultured neuroblastoma cells, most likely through inhibition of uptake or through noncompetitive inhibition. The potential inplications of these findings justify further study. (orig./VHE). With 4 figs., 1 tab.

  2. 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.

  3. Mice Lacking the β2 Adrenergic Receptor Have a Unique Genetic Profile before and after Focal Brain Ischaemia

    Directory of Open Access Journals (Sweden)

    Robin E White

    2012-08-01

    Full Text Available The role of the β2AR (β2 adrenergic receptor after stroke is unclear as pharmacological manipulations of the β2AR have produced contradictory results. We previously showed that mice deficient in the β2AR (β2KO had smaller infarcts compared with WT (wild-type mice (FVB after MCAO (middle cerebral artery occlusion, a model of stroke. To elucidate mechanisms of this neuroprotection, we evaluated changes in gene expression using microarrays comparing differences before and after MCAO, and differences between genotypes. Genes associated with inflammation and cell deaths were enriched after MCAO in both genotypes, and we identified several genes not previously shown to increase following ischaemia (Ccl9, Gem and Prg4. In addition to networks that were similar between genotypes, one network with a central core of GPCR (G-protein-coupled receptor and including biological functions such as carbohydrate metabolism, small molecule biochemistry and inflammation was identified in FVB mice but not in β2KO mice. Analysis of differences between genotypes revealed 11 genes differentially expressed by genotype both before and after ischaemia. We demonstrate greater Glo1 protein levels and lower Pmaip/Noxa mRNA levels in β2KO mice in both sham and MCAO conditions. As both genes are implicated in NF-κB (nuclear factor κB signalling, we measured p65 activity and TNFα (tumour necrosis factor α levels 24 h after MCAO. MCAO-induced p65 activation and post-ischaemic TNFα production were both greater in FVB compared with β2KO mice. These results suggest that loss of β2AR signaling results in a neuroprotective phenotype in part due to decreased NF-κB signalling, decreased inflammation and decreased apoptotic signalling in the brain.

  4. Characterization of a β-adrenergic-like octopamine receptor from the rice stem borer (Chilo suppressalis).

    Science.gov (United States)

    Wu, Shun-Fan; Yao, Yao; Huang, Jia; Ye, Gong-Yin

    2012-08-01

    Octopamine, the invertebrate counterpart of adrenaline and noradrenaline, plays a key role in regulation of many physiological and behavioral processes in insects. It modulates these functions through binding to specific octopamine receptors, which are typical rhodopsin-like G-protein coupled receptors. A cDNA encoding a seven-transmembrane receptor was cloned from the nerve cord of the rice stem borer, Chilo suppressalis, viz. CsOA2B2, which shares high sequence similarity to CG6989, a Drosophila β-adrenergic-like octopamine receptor (DmOctβ2R). We generated an HEK-293 cell line that stably expresses CsOA2B2 in order to examine the functional and pharmacological properties of this receptor. Activation of CsOA2B2 by octopamine increased the production of cAMP in a dose-dependent manner (EC(50)=2.33 nmol l(-1)), with a maximum response at 100 nmol l(-1). Tyramine also activated the receptor but with much less potency than octopamine. Dopamine and serotonin had marginal effects on cAMP production. Using a series of known agonists and antagonists for octopamine receptors, we observed a rather unique pharmacological profile for CsOA2B2 through measurements of cAMP. The rank order of potency of the agonists was naphazoline > clonidine. The activated effect of octopamine is abolished by co-incubation with phentolamine, mianserin or chlorpromazine. Using in vivo pharmacology, CsOA2B2 antagonists mianserin and phentolamine impaired the motor ability of individual rice stem borers. The results of the present study are important for a better functional understanding of this receptor as well as for practical applications in the development of environmentally sustainable pesticides.

  5. Characterization of a β-Adrenergic-Like Octopamine Receptor in the Oriental Fruit Fly, Bactrocera dorsalis (Hendel

    Directory of Open Access Journals (Sweden)

    Hui-Min Li

    2016-09-01

    Full Text Available The biogenic amine octopamine plays a critical role in the regulation of many physiological processes in insects. Octopamine transmits its action through a set of specific G-protein coupled receptors (GPCRs, namely octopamine receptors. Here, we report on a β-adrenergic-like octopamine receptor gene (BdOctβR1 from the oriental fruit fly, Bactrocera dorsalis (Hendel, a destructive agricultural pest that occurs in North America and the Asia-Pacific region. As indicated by RT-qPCR, BdOctβR1 was highly expressed in the central nervous system (CNS and Malpighian tubules (MT in the adult flies, suggesting it may undertake important roles in neural signaling in the CNS as well as physiological functions in the MT of this fly. Furthermore, its ligand specificities were tested in a heterologous expression system where BdOctβR1 was expressed in HEK-293 cells. Based on cyclic AMP response assays, we found that BdOctβR1 could be activated by octopamine in a concentration-dependent manner, confirming that this receptor was functional, while tyramine and dopamine had much less potency than octopamine. Naphazoline possessed the highest agonistic activity among the tested agonists. In antagonistic assays, mianserin had the strongest activity and was followed by phentolamine and chlorpromazine. Furthermore, when the flies were kept under starvation, there was a corresponding increase in the transcript level of BdOctβR1, while high or low temperature stress could not induce significant expression changes. The above results suggest that BdOctβR1 may be involved in the regulation of feeding processes in Bactrocera dorsalis and may provide new potential insecticide leads targeting octopamine receptors.

  6. Characterization of a β-Adrenergic-Like Octopamine Receptor in the Oriental Fruit Fly, Bactrocera dorsalis (Hendel)

    Science.gov (United States)

    Li, Hui-Min; Jiang, Hong-Bo; Gui, Shun-Hua; Liu, Xiao-Qiang; Liu, Hong; Lu, Xue-Ping; Smagghe, Guy; Wang, Jin-Jun

    2016-01-01

    The biogenic amine octopamine plays a critical role in the regulation of many physiological processes in insects. Octopamine transmits its action through a set of specific G-protein coupled receptors (GPCRs), namely octopamine receptors. Here, we report on a β-adrenergic-like octopamine receptor gene (BdOctβR1) from the oriental fruit fly, Bactrocera dorsalis (Hendel), a destructive agricultural pest that occurs in North America and the Asia-Pacific region. As indicated by RT-qPCR, BdOctβR1 was highly expressed in the central nervous system (CNS) and Malpighian tubules (MT) in the adult flies, suggesting it may undertake important roles in neural signaling in the CNS as well as physiological functions in the MT of this fly. Furthermore, its ligand specificities were tested in a heterologous expression system where BdOctβR1 was expressed in HEK-293 cells. Based on cyclic AMP response assays, we found that BdOctβR1 could be activated by octopamine in a concentration-dependent manner, confirming that this receptor was functional, while tyramine and dopamine had much less potency than octopamine. Naphazoline possessed the highest agonistic activity among the tested agonists. In antagonistic assays, mianserin had the strongest activity and was followed by phentolamine and chlorpromazine. Furthermore, when the flies were kept under starvation, there was a corresponding increase in the transcript level of BdOctβR1, while high or low temperature stress could not induce significant expression changes. The above results suggest that BdOctβR1 may be involved in the regulation of feeding processes in Bactrocera dorsalis and may provide new potential insecticide leads targeting octopamine receptors. PMID:27669213

  7. 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.

  8. Expressions of cardiac sympathetic norepinephrine transporter and β1-adrenergic receptor decreased in aged rats

    Institute of Scientific and Technical Information of China (English)

    He LI; Xiao-qing MA; Fan YE; Jing ZHANG; Xin ZHOU; Zhi-hong WANG; Yu-ming LI; Guo-yuan ZHANG

    2009-01-01

    Evidence suggests that the deterioration of communication between the sympathetic nervous system and cardiovas-cular system always accompanies the aging of human and animals. Cardiac sympathetic norepinephrine (NE) transporter (NET) on presynaptic membrane is a predominant component to eliminate released NE in the synaptic cleff and maintains the sensitivity of the β-adrenergic receptor (β-AR). In the present study, we investigated NET and β1-AR mRNA levels and sympathetic nerve density in cardiac sympathetic ganglion and leff ventricular myocardium in 2- and 16-month-old rats with Northern blot analysis and immunohistochemistry. The expression levels of NET mRNA, NET protein and β1-AR mRNA in the ganglia or myocardia of 16-month-old rats were markedly reduced by 67%, 26%, and 43%, respectively, in comparison with those in 2-month-old rats. Our results also show that aging induces a strong decrease of the catecholaminergic nerve fiber density.

  9. Synthesis of the sup 11 C-labelled. beta. -adrenergic receptor ligands atenolol, metoprolol and propanolol

    Energy Technology Data Exchange (ETDEWEB)

    Antoni, G.; Ulin, J.; Laangstroem, B. (Uppsala Univ. (Sweden). Dept. of Organic Chemistry)

    1989-01-01

    The {sup 11}C-labelled {beta}-adrenergic receptor ligands atenolol 1, metoprolol 2 and propranolol 3 have been synthesized by an N-alkylation reaction using (2-{sup 11}C)isopropyl iodide. The labelled isopropyl iodide was prepared in a one-pot reactor system from ({sup 11}C)carbon dioxide and obtained in 40% radiochemical yield within 14 min reaction time. The total reaction times for compounds 1-3, counted from the start of the isopropyl iodide synthesis and including purification were 45-55 min. The products were obtained in 5-15% radiochemical yields and with radiochemical purities higher than 98%. The specific activity ranged from 0.4 to 4 GBq/{mu}mol. In a typical experiment starting with 4 GBq around 75 MBq of product was obtained. (author).

  10. Increased circulating β2-adrenergic receptor autoantibodies are associated with smoking-related emphysema

    Science.gov (United States)

    Hu, Jia-yi; Liu, Bei-bei; Du, Yi-peng; Zhang, Yuan; Zhang, Yi-wei; Zhang, You-yi; Xu, Ming; He, Bei

    2017-01-01

    Smoking is a dominant risk factor for chronic obstructive pulmonary disease (COPD) and emphysema, but not every smoker develops emphysema. Immune responses in smokers vary. Some autoantibodies have been shown to contribute to the development of emphysema in smokers. β2-adrenergic receptors (β2-ARs) are important targets in COPD therapy. β2-adrenergic receptor autoantibodies (β2-AAbs), which may directly affect β2-ARs, were shown to be increased in rats with passive-smoking-induced emphysema in our current preliminary studies. Using cigarette-smoke exposure (CS-exposure) and active-immune (via injections of β2-AR second extracellular loop peptides) rat models, we found that CS-exposed rats showed higher serum β2-AAb levels than control rats before alveolar airspaces became enlarged. Active-immune rats showed increased serum β2-AAb levels, and exhibited alveolar airspace destruction. CS-exposed-active-immune treated rats showed more extensive alveolar airspace destruction than rats undergoing CS-exposure alone. In our current clinical studies, we showed that plasma β2-AAb levels were positively correlated with the RV/TLC (residual volume/total lung capacity) ratio (r = 0.455, p < 0.001) and RV%pred (residual volume/residual volume predicted percentage, r = 0.454, p < 0.001) in 50 smokers; smokers with higher plasma β2-AAb levels exhibited worse alveolar airspace destruction. We suggest that increased circulating β2-AAbs are associated with smoking-related emphysema. PMID:28262783

  11. Comparison of alpha-2 adrenergic receptors and their regulation in rodent and porcine species

    Energy Technology Data Exchange (ETDEWEB)

    Feller, D.J.; Bylund, D.B.

    1984-02-01

    The alpha-2 adrenergic antagonist (/sup 3/H)yohimbine (YOH) and the alpha-2 agonist (/sup 3/H)p-aminoclonidine (PAC) saturably label high-affinity binding sites in the submandibular gland from 3-week-old rats and 5-week-old pigs and in the lung from neonatal rats and 5-week-old pigs. (/sup 3/H)YOH had KD values of 5.5, 1.8, 0.45 and 0.22 nM in the rat gland and lung and porcine gland and lung, respectively. KD values of 2.4, 5.3 and 1.3 nM were found for (/sup 3/H)PAC in rodent and pig submandibular gland and pig lung, respectively. Both /sup 3/H-ligands labeled approximately the same density of sites within each tissue except in the rat lung in which (/sup 3/H)PAC binding was too low to reliably estimate. In all cases the pharmacologic profile was indicative of an alpha-2 adrenergic receptor site. However, the Ki of yohimbine vs. (/sup 3/H)PAC was 30- to 140-fold higher for the rodent relative to the porcine species. GTP decreased the affinity of (-)-epinephrine and PAC at (/sup 3/H)YOH-labeled sites in the pig gland and lung, but did not shift the affinity of epinephrine in the rat gland. These results suggest the possibility of subtype or species differences for the alpha-2 receptor. The Ki values of the antagonists YOH and phentolamine were different at (/sup 3/H)PAC and (/sup 3/H)YOH sites. GTP caused a dose-dependent reduction in (/sup 3/H)PAC binding in the porcine submandibular gland and lung. At 10 microM GTP, this loss was due to a decrease in /sup 3/H-agonist affinity, but not density.

  12. Cardiovascular effects of the novel histamine H2 receptor agonist amthamine: interaction with the adrenergic system.

    Science.gov (United States)

    Coruzzi, G; Gambarelli, E; Bertaccini, G; Timmerman, H

    1996-03-01

    The cardiovascular effects of the new histamine H2 receptor agonist amthamine were studied in the anaesthetized rat, with particular reference to a possible interaction with the adrenergic system. Amthamine (0.03-3 mumol/kg i.v.) caused vasodepressor responses which were antagonized by famotidine (3 mumol/kg i.v.). At higher doses (30-100 mumol/kg i.v.), amthamine induced a modest increase in the mean arterial pressure, which was significantly enhanced by the blockade of H2 receptors and significantly reduced by the alpha 2 adrenoceptor antagonist yohimbine (1 mumol/kg i.v.). The vasopressor response to amthamine was not modified in rats pre-treated with reserpine or 6-hydroxydopamine, and was only minimally modified in adrenalectomized animals, thus suggesting a predominant interaction with postjunctional alpha 2 adrenoceptors in the vascular muscle. The H2 receptor agonist dimaprit (0.3-100 mumol/kg i.v.) caused a reduction in arterial pressure, which was antagonized by famotidine, no pressor response being unmasked. Dimaprit (0.1-30 mumol/kg i.v.) did not modify heart rate but caused a modest bradycardia at 100 mumol/kg i.v. Amthamine (1-100 mumol/kg i.v.) induced a dose-dependent tachycardia, which was only partially (approximately 20%) reduced by famotidine and was totally blocked by propranolol (0.3 mg/kg i.v.). This effect was significantly reduced in rats pre-treated with reserpine or 6-hydroxydopamine and was further reduced by cocaine, thus suggesting a tyramine-like action of amthamine. In conclusion, these data demonstrate that the H2 receptor agonist amthamine can also interact with the adrenergic system when used at doses higher than those necessary to activate H2 receptors. Whereas the increase in blood pressure induced by amthamine seems to be mainly mediated by a direct activation of postjunctional alpha 2 adrenoceptors, the increase in heart rate is predominantly due to neuronal release of catecholamines. These effects should be considered when

  13. Commercially available antibodies directed against α-adrenergic receptor subtypes and other G protein-coupled receptors with acceptable selectivity in flow cytometry experiments.

    Science.gov (United States)

    Tripathi, Abhishek; Gaponenko, Vadim; Majetschak, Matthias

    2016-02-01

    Several previous reports suggested that many commercially available antibodies directed against G protein-coupled receptors (GPCR) lack sufficient selectivity. Accordingly, it has been proposed that receptor antibodies should be validated by at least one of several criteria, such as testing tissues or cells after knockout or silencing of the corresponding gene. Here, we tested whether 12 commercially available antibodies directed against α-adrenergic receptor (AR) subtypes (α1A/B/D, α2A/B/C), atypical chemokine receptor 3 (ACKR3), and vasopressin receptor 1A (AVPR1A) suffice these criteria. We detected in flow cytometry experiments with human vascular smooth muscle cells that the fluorescence signals from each of these antibodies were reduced by 46 ± 10 %-91 ± 2 % in cells treated with commercially available small interfering RNA (siRNA) specific for each receptor, as compared with cells that were incubated with non-targeting siRNA. The tested antibodies included anti-ACKR3 (R&D Systems, mab42273), for which specificity has previously been demonstrated. Staining with this antibody resulted in 72 ± 5 % reduction of the fluorescence signal after ACKR3 siRNA treatment. Furthermore, staining with anti-α1A-AR (Santa Cruz, sc1477) and anti-ACKR3 (Abcam, ab38089), which have previously been reported to be non-specific, resulted in 70 ± 19 % and 80 ± 4 % loss of the fluorescence signal after α1A-AR and ACKR3 siRNA treatment, respectively. Our findings demonstrate that the tested antibodies show reasonable selectivity for their receptor target under our experimental conditions. Furthermore, our observations suggest that the selectivity of GPCR antibodies depends on the method for which the antibody is employed, the species from which cells/tissues are obtained, and on the type of specimens (cell, tissue/cell homogenate, or section) tested.

  14. Identification of high affinity bioactive Salbutamol conformer directed against mutated (Thr164Ile) beta 2 adrenergic receptor.

    Science.gov (United States)

    Bandaru, Srinivas; Tiwari, Geet; Akka, Jyothy; Marri, Vijaya Kumar; Alvala, Mallika; Gutlapalli, Venkata Ravi; Nayarisseri, Anuraj; Mundluru, Hema Prasad

    2015-01-01

    Salbutamol forms an important and widely administered β2 agonist prescribed in the symptomatic treatment of bronchial asthma. Unfortunately, a subset of patients show refractoriness to it owing to ADRB2 gene variant (rs 1800888). The variant substitutes Thr to Ile at the position 164 in the β2 adrenergic receptor leading to sub-optimal binding of agonists. The present study aims to associate the Salbutamol response with the variant and select the bioactive conformer of Sabutamol with optimal binding affinity against mutated receptor by in silico approaches. To assess bronchodilator response spirometry was performed before and 15 min after Salbutamol (200 mcg) inhalation. Responders to Salbutamol were categorized if percentage reversibility was greater than or equal to 12%, while those showing FEV₁ reversibility less than 12% were classified as non-responders. Among the 344 subjects screened, 238 were responders and 106 were non-responders. The frequency of mutant allele "T" was significantly higher in case of non-responders (p Salbutamol conformer ensembles supported by systematic search algorithm. 4369 conformers were generated of which only 1882 were considered bioactive conformers (threshold RMSD≤1 in reference to normalized structure of salbutamol). All the bioactive conformers were evaluated for the binding affinity against (Thr164 Ile) receptor through MolDock aided docking algorithm. One of the bioactive conformer (P.E. = -57.0038, RMSD = 0.6) demonstrated 1.54 folds greater affinity than the normal Salbutamol in the mutated receptor. The conformer identified in the present study may be put to pharmacodynamic and pharmacokinetic studies in future ahead.

  15. Environmental factors and beta2-adrenergic receptor polymorphism: influence on the energy expenditure and nutritional status of obese women.

    Science.gov (United States)

    Rosado, Eliane Lopes; Bressan, Josefina; Martínez, J Alfredo

    2015-05-01

    Our aim was to evaluate the influence of the Gln27Glu polymorphism of the β2-adrenergic receptor (ADRβ2) gene, fat intake and physical activity on the energy expenditure (EE) and nutritional status of obese women. Sixty obese women (30-46 years) participated in the study and were assigned to three groups depending on the genotypes: Gln27Gln, Gln27Glu and Glu27Glu. At baseline and after nutritional intervention, the anthropometric and body composition (bioelectrical impedance), dietary, EE (indirect calorimetry) and biochemical variables were measured. All women received a high-fat test meal to determine the postprandial EE (short-term) and an energy-restricted diet for 10 weeks (long term). The frequencies of Gln27Gln, Gln27Glu and Glu27Glu were 36.67, 40.0 and 23.33 %, respectively. Anthropometric and biochemical variables and EE did not differ between groups, although women who had no polymorphism demonstrated decreased carbohydrate oxidation. On the other hand, the Glu27Glu genotype showed a positive relation with EE in physical activity and fat oxidation. The environmental factors and Gln27Glu polymorphism did not influence the nutritional status and EE of obese women, but physical activity in obese women with the polymorphism in the ADRβ2 gene can promote fat oxidation. The results suggest that encouraging the practice of physical exercise is important considering the high frequency of this polymorphism in obese subjects.

  16. Crystal structure of the β2 adrenergic receptor-Gs protein complex

    Energy Technology Data Exchange (ETDEWEB)

    Rasmussen, Søren G.F.; DeVree, Brian T; Zou, Yaozhong; Kruse, Andrew C; Chung, Ka Young; Kobilka, Tong Sun; Thian, Foon Sun; Chae, Pil Seok; Pardon, Els; Calinski, Diane; Mathiesen, Jesper M; Shah, Syed T.A.; Lyons, Joseph A; Caffrey, Martin; Gellman, Samuel H; Steyaert, Jan; Skiniotis, Georgios; Weis, William I; Sunahara, Roger K; Kobilka, Brian K [Brussels; (Trinity); (Michigan); (Stanford-MED); (Michigan-Med); (UW)

    2011-12-07

    G protein-coupled receptors (GPCRs) are responsible for the majority of cellular responses to hormones and neurotransmitters as well as the senses of sight, olfaction and taste. The paradigm of GPCR signalling is the activation of a heterotrimeric GTP binding protein (G protein) by an agonist-occupied receptor. The β2 adrenergic receptor2AR) activation of Gs, the stimulatory G protein for adenylyl cyclase, has long been a model system for GPCR signalling. Here we present the crystal structure of the active state ternary complex composed of agonist-occupied monomeric β2AR and nucleotide-free Gs heterotrimer. The principal interactions between the β2AR and Gs involve the amino- and carboxy-terminal α-helices of Gs, with conformational changes propagating to the nucleotide-binding pocket. The largest conformational changes in the β2AR include a 14Å outward movement at the cytoplasmic end of transmembrane segment 6 (TM6) and an α-helical extension of the cytoplasmic end of TM5. The most surprising observation is a major displacement of the α-helical domain of Gαs relative to the Ras-like GTPase domain. This crystal structure represents the first high-resolution view of transmembrane signalling by a GPCR.

  17. Pharmacological profiles of alpha 2 adrenergic receptor agonists identified using genetically altered mice and isobolographic analysis.

    Science.gov (United States)

    Fairbanks, Carolyn A; Stone, Laura S; Wilcox, George L

    2009-08-01

    Endogenous, descending noradrenergic fibers impose analgesic control over spinal afferent circuitry mediating the rostrad transmission of pain signals. These fibers target alpha 2 adrenergic receptors (alpha(2)ARs) on both primary afferent terminals and secondary neurons, and their activation mediates substantial inhibitory control over this transmission, rivaling that of opioid receptors which share a similar pattern of distribution. The terminals of primary afferent nociceptive neurons and secondary spinal dorsal horn neurons express alpha(2A)AR and alpha(2C)AR subtypes, respectively. Spinal delivery of these agents serves to reduce their side effects, which are mediated largely at supraspinal sites, by concentrating the drugs at the spinal level. Targeting these spinal alpha(2)ARs with one of five selective therapeutic agonists, clonidine, dexmedetomidine, brimonidine, ST91 and moxonidine, produces significant antinociception that can work in concert with opioid agonists to yield synergistic antinociception. Application of several genetically altered mouse lines had facilitated identification of the primary receptor subtypes that likely mediate the antinociceptive effects of these agents. This review provides first an anatomical description of the localization of the three subtypes in the central nervous system, second a detailed account of the pharmacological history of each of the six primary agonists, and finally a comprehensive report of the specific interactions of other GPCR agonists with each of the six principal alpha(2)AR agonists featured.

  18. Altered Expression Profile of Renal α1D-Adrenergic Receptor in Diabetes and Its Modulation by PPAR Agonists

    Directory of Open Access Journals (Sweden)

    Xueying Zhao

    2014-01-01

    Full Text Available Alpha1D-adrenergic receptor (α1D-AR plays important roles in regulating physiological and pathological responses mediated by catecholamines, particularly in the cardiovascular and urinary systems. The present study was designed to investigate the expression profile of α1D-AR in the diabetic kidneys and its modulation by activation of peroxisome proliferator-activated receptors (PPARs. 12-week-old Zucker lean (ZL and Zucker diabetic fatty (ZD rats were treated with fenofibrate or rosiglitazone for 8–10 weeks. Gene microarray, real-time PCR, and confocal immunofluorescence microscopy were performed to assess mRNA and protein expression of α1D-AR in rat kidney tissue. Using microarray, we found that α1D-AR gene was dramatically upregulated in 22-week-old ZD rats compared to ZL controls. Quantitative PCR analysis verified a 16-fold increase in α1D-AR mRNA in renal cortex from ZD animals compared to normal controls. Chronic treatment with fenofibrate or rosiglitazone reduced renal cortical α1D-AR gene. Immunofluorescence staining confirmed that α1D-AR protein was induced in the glomeruli and tubules of diabetic rats. Moreover, dual immunostaining for α1D-AR and kidney injury molecule-1 indicated that α1D-AR was expressed in dedifferentiated proximal tubules of diabetic Zucker rats. Taken together, our results show that α1D-AR expression is upregulated in the diabetic kidneys. PPAR activation suppressed renal expression of α1D-AR in diabetic nephropathy.

  19. Characterization of a panel of six β2-adrenergic receptor antibodies by indirect immunofluorescence microscopy

    Science.gov (United States)

    Koryakina, Yulia A; Fowler, Tristan W; Jones, Stacie M; Schnackenberg, Bradley J; Cornett, Lawrence E; Kurten, Richard C

    2008-01-01

    Background The β2-adrenergic receptor (β2AR) is a primary target for medications used to treat asthma. Due to the low abundance of β2AR, very few studies have reported its localization in tissues. However, the intracellular location of β2AR in lung tissue, especially in airway smooth muscle cells, is very likely to have a significant impact on how the airways respond to β-agonist medications. Thus, a method for visualizing β2AR in tissues would be of utility. The purpose of this study was to develop an immunofluorescent labeling technique for localizing native and recombinant β2AR in primary cell cultures. Methods A panel of six different antibodies were evaluated in indirect immunofluorescence assays for their ability to recognize human and rat β2AR expressed in HEK 293 cells. Antibodies capable of recognizing rat β2AR were identified and used to localize native β2AR in primary cultures of rat airway smooth muscle and epithelial cells. β2AR expression was confirmed by performing ligand binding assays using the β-adrenergic antagonist [3H] dihydroalprenolol ([3H]DHA). Results Among the six antibodies tested, we identified three of interest. An antibody developed against the C-terminal 15 amino acids of the human β2AR (Ab-Bethyl) specifically recognized human but not rat β2AR. An antibody developed against the C-terminal domain of the mouse β2AR (Ab-sc570) specifically recognized rat but not human β2AR. An antibody developed against 78 amino acids of the C-terminus of the human β2AR (Ab-13989) was capable of recognizing both rat and human β2ARs. In HEK 293 cells, the receptors were predominantly localized to the cell surface. By contrast, about half of the native rat β2AR that we visualized in primary cultures of rat airway epithelial and smooth muscle cells using Ab-sc570 and Ab-13989 was found inside cells rather than on their surface. Conclusion Antibodies have been identified that recognize human β2AR, rat β2AR or both rat and human β2AR

  20. Characterization of a panel of six β2-adrenergic receptor antibodies by indirect immunofluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Jones Stacie M

    2008-04-01

    Full Text Available Abstract Background The β2-adrenergic receptor (β2AR is a primary target for medications used to treat asthma. Due to the low abundance of β2AR, very few studies have reported its localization in tissues. However, the intracellular location of β2AR in lung tissue, especially in airway smooth muscle cells, is very likely to have a significant impact on how the airways respond to β-agonist medications. Thus, a method for visualizing β2AR in tissues would be of utility. The purpose of this study was to develop an immunofluorescent labeling technique for localizing native and recombinant β2AR in primary cell cultures. Methods A panel of six different antibodies were evaluated in indirect immunofluorescence assays for their ability to recognize human and rat β2AR expressed in HEK 293 cells. Antibodies capable of recognizing rat β2AR were identified and used to localize native β2AR in primary cultures of rat airway smooth muscle and epithelial cells. β2AR expression was confirmed by performing ligand binding assays using the β-adrenergic antagonist [3H] dihydroalprenolol ([3H]DHA. Results Among the six antibodies tested, we identified three of interest. An antibody developed against the C-terminal 15 amino acids of the human β2AR (Ab-Bethyl specifically recognized human but not rat β2AR. An antibody developed against the C-terminal domain of the mouse β2AR (Ab-sc570 specifically recognized rat but not human β2AR. An antibody developed against 78 amino acids of the C-terminus of the human β2AR (Ab-13989 was capable of recognizing both rat and human β2ARs. In HEK 293 cells, the receptors were predominantly localized to the cell surface. By contrast, about half of the native rat β2AR that we visualized in primary cultures of rat airway epithelial and smooth muscle cells using Ab-sc570 and Ab-13989 was found inside cells rather than on their surface. Conclusion Antibodies have been identified that recognize human β2AR, rat β2AR or

  1. Solubilization of a guanyl nucleotide-sensitive alpha/sub 1/ adrenergic receptor from liver membranes

    Energy Technology Data Exchange (ETDEWEB)

    Harris, S.I.; Moss, J.

    1987-05-01

    Rat liver membranes incubated with norepinephrine before solubilization with digitonin yielded a soluble hormone-receptor complex from which the release of tightly bound norepinephrine was facilitated by guanyl nucleotides. Binding of the alpha/sub 1/-adrenergic receptor antagonist, (/sup 3/H)-prazosin, to the soluble preparation was utilized as a gauge of guanyl nucleotide-induced release of receptor-bound agonist. The following potency series was obtained with regard to the ability of guanyl nucleotides to facilitate (/sup 3/H)-prazosin binding to the solubilized preparation: guanosine 5'-0-(3-thiotriphosphate)(K/sub 1/2/ = 2.5 nM), guanylyl-imidodiphosphate (K/sub 1/2/ = 10 nM), guanosine triphosphate (K/sub 1/2/ = 34 nM) and adenylyl-imidodiphosphate (K/sub 1/2/ > 1 mM). In the presence of guanylyl-imidodiphosphate (0.4 mM), the receptor population displayed monotonic binding parameters with a K/sub d/ for (/sup 3/H)-prazosin of 1.16 nM by Scatchard analysis. Competition curves against (/sup 3/H)-prazosin with the antagonists phentolamine and yohimbine revealed respective K/sub i/'s of .089 ..mu..M and 1.8 ..mu..M; curves with the agonists norepinephrine and isoproterenol yielded respective K/sub i/'s of 6.2..mu..M and 360 ..mu..M. Competition curves performed in the absence of guanyl nucleotide were complex demonstrating an apparent increase in affinity for agonists and an apparent decrease in affinity for antagonists. These curve shifts are consistent with the conversion of receptor to and from the guanyl nucleotide-sensitive state as a function of competing ligand concentration.

  2. Activation of antilipolytic alpha(2)-adrenergic receptors by epinephrine during exercise in human adipose tissue.

    Science.gov (United States)

    Stich, V; de Glisezinski, I; Crampes, F; Suljkovicova, H; Galitzky, J; Riviere, D; Hejnova, J; Lafontan, M; Berlan, M

    1999-10-01

    The involvement of the antilipolytic alpha(2)-adrenergic pathway and the specific role of epinephrine in the control of lipolysis during exercise in adipose tissue (AT) were investigated in healthy male subjects (age: 24.1 +/- 2.2 yr; body mass index: 23.0 +/- 1.6). An in vitro study carried out on isolated adipocytes showed that the weak lipolytic effect of epinephrine was potentiated after blockade of alpha(2)-adrenergic receptor (AR) by an alpha(2)-AR antagonist and reached that of isoproterenol, a beta-AR agonist. The effect of the nonselective alpha(2)-AR antagonist phentolamine on the response of the extracellular glycerol concentration (EGC) in AT during two successive bouts of aerobic exercise (50% maximum O(2) uptake, 60 min duration) was evaluated using the microdialysis method. The metabolic responses measured in perfused probes with Ringer solution were compared with those obtained in perfused probes with Ringer plus 0.1 mmol/l phentolamine. Plasma norepinephrine level was not different during the two exercise bouts, whereas that of epinephrine was 2.5-fold higher during the second exercise. EGC in AT was twofold higher in the second compared with the first exercise, and the same response pattern was found for plasma glycerol. The exercise-induced increase in EGC was higher in the probe perfused with phentolamine compared with the control probe in both bouts of exercise. However, the potentiating effect of phentolamine on EGC was significant during the second exercise bout but did not reach a significant level during the first. These results suggest that epinephrine is involved in the control of lipid mobilization through activation of antilipolytic alpha(2)-AR in human subcutaneous AT during exercise.

  3. Beta-adrenergic receptors are differentially expressed in distinct interneuron subtypes in the rat hippocampus.

    Science.gov (United States)

    Cox, David J; Racca, Claudia; LeBeau, Fiona E N

    2008-08-20

    Noradrenaline (NA) acting via beta-adrenergic receptors (betaARs) plays an important role in the modulation of memory in the hippocampus. betaARs have been shown to be expressed in principal cells, but their distribution across different interneuron classes is unknown. We have used specific interneuron markers including calcium binding proteins (parvalbumin, calbindin, and calretinin) and neuropeptides (somatostatin, neuropeptide Y, and cholecystokinin) together with either beta1AR or beta2AR to determine the distribution of these receptors in all major subfields of the hippocampus. We found that beta1AR-expressing interneurons were more prevalent in the CA3 and CA1 regions of the hippocampus than in the dentate gyrus, where they were relatively sparse. beta2AR-expressing interneurons were more uniformly distributed between all three regions of the hippocampus. A high proportion of neuropeptide Y-containing interneurons in the dentate gyrus co-expressed beta2AR. beta1AR labeling was common in interneurons expressing somatostatin and parvalbumin in the CA3 and CA1 regions, particularly in the stratum oriens of these regions. beta2AR labeling was more likely to be found than beta1AR labeling in cholecystokinin-expressing interneurons. In contrast, calretinin-containing interneurons were virtually devoid of beta1AR or beta2AR labeling. These regional and interneuron type-specific differences suggest functionally distinct roles for NA in modulating hippocampal activity via activation of betaARs.

  4. 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.

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

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    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.

  6. 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...

  7. Association of morbid obesity,metabolic syndrome and polymorphism of β3-adrenergic receptor gene in the Hasake population in xinjiang%β3肾上腺素能受体基因多态与新疆哈萨克族人腹型肥胖和代谢综合征的相关研究

    Institute of Scientific and Technical Information of China (English)

    郭艳英; 潘慧娟; 王坤; 赵蕾; 何秉贤

    2008-01-01

    目的 检测新疆哈萨克族人群中β3肾上腺素能受体(β3-AR)Trp64Arg位点的等位基因频率和基因型频率,分析β3-AR基因在腹型肥胖、代谢综合征发生、发展中的作用.方法 应用聚合酶链反应和限制性片断长度多态性技术检测172例代谢综合征(MS)、92例单纯腹型肥胖和92例正常人的基因型,同时测定相关的生化指标,进行病例-对照研究.结果 β3-AR Trp64Arg位点的基因型频率在三组间差异无统计学意义.结论 β3-AR Trp64Arg多态与哈萨克族人腹型肥胖、MS的发生无明显关联.%Objective To investigate the genotype of Trp64Arg polymorphism of β3-adrenergic receptor gene and analyze the role ofβ3-adrenerglc receptor gene in the pathogenesis of morbid obesity and metabolic syndrome(MS).Methods PCR-restriction fragment length polymorphism Was used to detect the genotypes of 172 patients with MS,92 patient.with morbid obesity and 92 controls,and some biochemlcal indexes were detected.The association of the polymorohism with morbid obesity and MS Was assessed in case-control study.Resuits No statistically significant differences were found in the frequencies of Trp64Arg of β3-AR among the three groups.Conclusion Trp64Arg polymorphism of β3-AR was not significandy associated with morbid obesity and MS in the Hazak in xinjiang.

  8. Norepinephrine-Induced Adrenergic Activation Strikingly Increased the Atrial Fibrillation Duration through β1- and α1-Adrenergic Receptor-Mediated Signaling in Mice.

    Directory of Open Access Journals (Sweden)

    Kenji Suita

    Full Text Available Atrial fibrillation (AF is the most common arrhythmias among old people. It causes serious long-term health problems affecting the quality of life. It has been suggested that the autonomic nervous system is involved in the onset and maintenance of AF in human. However, investigation of its pathogenesis and potential treatment has been hampered by the lack of suitable AF models in experimental animals.Our aim was to establish a long-lasting AF model in mice. We also investigated the role of adrenergic receptor (AR subtypes, which may be involved in the onset and duration of AF.Trans-esophageal atrial burst pacing in mice could induce AF, as previously shown, but with only a short duration (29.0 ± 8.1 sec. We found that adrenergic activation by intraperitoneal norepinephrine (NE injection strikingly increased the AF duration. It increased the duration to more than 10 minutes, i.e., by more than 20-fold (656.2 ± 104.8 sec; P<0.001. In this model, a prior injection of a specific β1-AR blocker metoprolol and an α1-AR blocker prazosin both significantly attenuated NE-induced elongation of AF. To further explore the mechanisms underlying these receptors' effects on AF, we assessed the SR Ca(2+ leak, a major trigger of AF, and consequent spontaneous SR Ca(2+ release (SCR in atrial myocytes. Consistent with the results of our in-vivo experiments, both metoprolol and prazosin significantly inhibited the NE-induced SR Ca(2+ leak and SCR. These findings suggest that both β1-AR and α1-AR may play important roles in the development of AF.We have established a long-lasting AF model in mice induced by adrenergic activation, which will be valuable in future AF study using experimental animals, such as transgenic mice. We also revealed the important role of β1- and α1-AR-mediated signaling in the development of AF through in-vivo and in-vitro experiments.

  9. Prostaglandin (PG) E3 synthesis elicted by adrenergic stimuli in guinea-pig trachea (GPT) is mediated primarily by B2 adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Nadel, G.L.; Malik, K.U.; Lew, D.B. (Univ. of Tennessee, Memphis (United States))

    1990-02-26

    The purpose of this study was to examine arachidonic acid (AA) metabolism and to characterize the type of adrenergic receptor (AR) involved in the production of the major metabolite of this fatty acid. ({sup 14}C)AA was incubated with GPT-rings and the radiolabelled products were extracted and separated by TLC method. The medium was also assayed for radiolabelled immunoreactive PG's (iPG's) and leukotrienes (LT) B4 and C4 by RIA or Enzyme immunoassay (EIA) after exposure to various AR agonists. ({sup 14}C)AA was incorporated into GPT-rings and metabolized mainly into iPGE2 and smaller amounts into PGF2{alpha}. Trace amounts of PGD2 and 6-keto-PGF1{alpha} but not LTB4 or LTC4 were detected by RIA and/or EIA. Incubation of GPT rings for 15 minutes with isoproterenol and salbutamol resulted in a significant increase of PGE2 synthesis (optimum conc: 10{sup {minus}7}, 10{sup {minus}7}M respectively). In contrast, dobutamine, norepinephrine, phenylnephrine and xylazine (up to 10{sup {minus}6}M) did not significantly increase PGE2 production. Isoproterenol-induced iPGE2 production was inhibited by a selective {beta}2 antagonist, butoxamine (70%: 10{sup {minus}7}M, 91%: 10{sup {minus}6}M) and somewhat reduced by {beta}1 antagonists practolol and metoprolol (30-64%:10{sup {minus}6}M). These data suggest that isoproterenol induced iPGE2 synthesis is primarily mediated via activation of {beta}2 adrenergic receptor.

  10. Alpha2-Adrenergic Receptors and Breast Tumor Stroma: A Novel Pathway Driving Breast Cancer Growth and Metastasis

    Science.gov (United States)

    2015-10-01

    1 AWARD NUMBER: W81XWH-13-1-0439 TITLE: Alpha2-Adrenergic Receptors and Breast Tumor Stroma: A Novel Pathway Driving Breast Cancer Growth and...treatment of breast cancer often experience severe and chronic psychological stress. The sympathetic nervous system (SNS) is an important pathway by which...Sephton SE, McDonald PG, et al. The influence of bio-behavioural factors on tumour biology: pathways and mechanisms. Nat Rev Cancer . 2006;6:240-8. 3

  11. Protein kinase Cζ regulates phospholipase D activity in rat-1 fibroblasts expressing the α1A adrenergic receptor

    Directory of Open Access Journals (Sweden)

    Bourgoin Sylvain G

    2004-01-01

    Full Text Available Abstract Background Phenylephrine (PHE, an α1 adrenergic receptor agonist, increases phospholipase D (PLD activity, independent of classical and novel protein kinase C (PKC isoforms, in rat-1 fibroblasts expressing α1A adrenergic receptors. The aim of this study was to determine the contribution of atypical PKCζ to PLD activation in response to PHE in these cells. Results PHE stimulated a PLD activity as demonstrated by phosphatidylethanol production. PHE increased PKCζ translocation to the particulate cell fraction in parallel with a time-dependent decrease in its activity. PKCζ activity was reduced at 2 and 5 min and returned to a sub-basal level within 10–15 min. Ectopic expression of kinase-dead PKCζ, but not constitutively active PKCζ, potentiated PLD activation elicited by PHE. A cell-permeable pseudosubstrate inhibitor of PKCζ reduced basal PKCζ activity and abolished PHE-induced PLD activation. Conclusion α1A adrenergic receptor stimulation promotes the activation of a PLD activity by a mechanism dependent on PKCζ; Our data also suggest that catalytic activation of PKCζ is not required for PLD stimulation.

  12. Locus Coeruleus Stimulation Facilitates Long-Term Depression in the Dentate Gyrus That Requires Activation of β-Adrenergic Receptors

    Science.gov (United States)

    Hansen, Niels; Manahan-Vaughan, Denise

    2015-01-01

    Synaptic plasticity comprises a cellular mechanism through which the hippocampus most likely enables memory formation. Neuromodulation, related to arousal, is a key aspect in information storage. The activation of locus coeruleus (LC) neurons by novel experience leads to noradrenaline release in the hippocampus at the level of the dentate gyrus (DG). We explored whether synaptic plasticity in the DG is influenced by activation of the LC via electrical stimulation. Coupling of test-pulses that evoked stable basal synaptic transmission in the DG with stimulation of the LC induced β-adrenoreceptor-dependent long-term depression (LTD) at perforant path–DG synapses in adult rats. Furthermore, persistent LTD (>24 h) induced by perforant path stimulation also required activation of β-adrenergic receptors: Whereas a β-adrenergic receptor antagonist (propranolol) prevented, an agonist (isoproterenol) strengthened the persistence of LTD for over 24 h. These findings support the hypothesis that persistent LTD in the DG is modulated by β-adrenergic receptors. Furthermore, LC activation potently facilitates DG LTD. This suggests in turn that synaptic plasticity in the DG is tightly regulated by activity in the noradrenergic system. This may reflect the role of the LC in selecting salient information for subsequent synaptic processing in the hippocampus. PMID:24464942

  13. Association of polymorphism of β3-adrenergic receptor gene and the leptin gene with Kazak obese children in Xinjiang%β3肾上腺素能受体基因及瘦素基因多态性与新疆哈萨克族儿童肥胖的关系

    Institute of Scientific and Technical Information of China (English)

    朱翠翠; 张季红; 徐佩茹; 李敏; 马冬梅

    2013-01-01

    Objective To investigate the association between C2549A polymorphism of leptin gene and the Trp64Arg polymorphism of the β3-adrenergic receptor gene(β3-AR gene) and obesity in Kazak school-age children.Methods Totally 92 obese children and 71 healthy controls were selected from 6 to 12 years old in Kazak school-age children from the area around Urumqi.Genotype of the C2549A polymorphism of leptin gene and the Trp64Arg polymor phism of β3-AR gene were determined by polymerase chain reaction and restriction fragment length polymorphism methods.Results 1.The difference in distribution of the β3-AR gene Trp64Arg genotype of obesity and healthy controls of Kazak children was statistically significant (x2 =10.472,P < 0.05),but the difference in distribution of the alleles was not statistically significant (x2 =3.541,P > 0.05).2.The differences in distribution of the leptin C2549A genotype and alleles of the 2 groups were all statistically significant,and the odds ratio of the alleles(0.608) and 95% CI 0.380-0.972 suggested that the mutation occurrence of obesity might have certain protective effect.3.The difference in distribution of the genotype of β3-AR gene Trp64Arg polymorphism and leptin gene promoter area C2549A polymorphism in the same individual joint action of 2 groups was statistically significant (x2 =15.978,P < 0.05),but the difference in distribution of the alleles in the same individual joint action of 2 groups was not statistically significant (x2 =6.362,P > 0.05).Conclusions 1.There were distributions of the Trp64Arg polymorphism of β3-AR gene and the C2549A polymorphism of leptin gene in Kazak school-aged children in Xinjiang.2.These results suggested that C2549A mutation of leptin gene might have certain protective effect in Kazak children obesity,and the Trp64Arg polymorphism of β3-AR gene might be associated with Kazak children obesity.3.These results suggested that the Trp64Arg polymorphism of β3-AR gene and the C2549A polymorphism

  14. Receptor subtype involved in α1-adrenergic receptor-mediated Ca2+ sig-naling in cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    Da-li LUO; Jian GAO; Lin-lin FAN; Yu TANG; You-yi ZHANG; Qi-de HAN

    2007-01-01

    Aim: The enhancement of intracellular Ca2+ signaling in response to α1-adrener-gic receptor (α1-AR) stimulation is an essential signal transduction event in the regulation of cardiac functions, such as cardiac growth, cardiac contraction, and cardiac adaptation to various situations. The present study was intended to determine the role(s) of the α1-AR subtype(s) in mediating this response. Methods: We evaluated the effects of subtype-specific agonists and antagonists of the α1- AR on the intracellular Ca2+ signaling of neonatal rat ventricular myocytes using a confocal microscope. Results: After being cultured for 48 h, the myocytes exhibited spontaneous local Ca2+ release, sparks, and global Ca2+ transients. The activation of the α1-AR with phenylephrine, a selective agonist of the α1-AR, dose-dependently increased the frequency of Ca2+ transients with an EC50 value of 2.3 μmol/L. Blocking the α1A-AR subtype with 5-methyhirapidil (5-Mu) inhi-bited the stimulatory effect of phenylephrine with an IC50 value of 6.7 nmol/L. In contrast, blockade of the α1B-AR and α1D-AR subtypes with chloroethylclonidine and BMY 7378, respectively, did not affect the phenylephrine effect. Similarly, the local Ca2+ spark numbers were also increased by the activation of theα1-AR, and this effect could be abolished selectively by 5-Mu. More importantly, A61603, a novel selective α1A-AR agonist, mimicked the effects of phenylephrine, but with more potency (EC50 value =6.9 nmol/L) in the potentiation of Ca2+ transients, and blockade of the α1A-AR by 5-Mu caused abolishment of its effects. Conclusion: These results indicate that α1-adrenergic stimulation of intracellular Ca2+ activity is mediated selectively by the α1A-AR.

  15. Melatonin receptor-mediated protection against myocardial ischaemia/reperfusion injury: role of its anti-adrenergic actions.

    Science.gov (United States)

    Genade, Sonia; Genis, Amanda; Ytrehus, Kirsti; Huisamen, Barbara; Lochner, Amanda

    2008-11-01

    Melatonin has potent cardioprotective properties. These actions have been attributed to its free radical scavenging and anti-oxidant actions, but may also be receptor mediated. Melatonin also exerts powerful anti-adrenergic actions based on its effects on contractility of isolated papillary muscles. The aims of this study were to determine whether melatonin also has anti-adrenergic effects on the isolated perfused rat heart, to determine the mechanism thereof and to establish whether these actions contribute to protection of the heart during ischaemia/reperfusion. The results showed that melatonin (50 microM) caused a significant reduction in both isoproterenol (10(-7) M) and forskolin (10(-6) M) induced cAMP production and that both these responses were melatonin receptor dependent, since the blocker, luzindole (5 x 10(-6) M) abolished this effect. Nitric oxide (NO), as well as guanylyl cyclase are involved, as L-NAME (50 microM), an NO synthase inhibitor and ODQ (20 microM), a guanylyl cyclase inhibitor, significantly counteracted the effects of melatonin. Protein kinase C (PKC), as indicated by the use of the inhibitor bisindolylmaleimide (50 microM), also play a role in melatonin's anti-adrenergic actions. These actions of melatonin are involved in its cardioprotection: simultaneous administration of L-NAME or ODQ with melatonin, before and after 35 min regional ischaemia, completely abolished its cardioprotection. PKC, on the other hand, had no effect on the melatonin-induced reduction in infarct size. Cardioprotection by melatonin was associated with a significant activation of PKB/Akt and attenuated activation of the pro-apoptotic kinase, p38MAPK during early reperfusion. In summary, the results show that melatonin-induced cardioprotection may be receptor dependent, and that its anti-adrenergic actions, mediated by NOS and guanylyl cyclase activation, are important contributors.

  16. Pharmacological targeting of β-adrenergic receptor functions abrogates NF-κB signaling and MMP-9 secretion in medulloblastoma cells

    Directory of Open Access Journals (Sweden)

    Borhane Annabi

    2010-11-01

    Full Text Available Borhane Annabi1,*, Eric Vaillancourt-Jean1,*, Alexander G Weil3, Richard Béliveau2,31Laboratoire d’Oncologie Moléculaire, Département de Chimie, Centre de Recherche BioMED, 2Laboratory of Molecular Medicine, Université du Québec à Montréal, Quebec, Canada; 3Department of Neurosurgery, CHUM Notre Dame, Montreal, Quebec, Canada; *These authors contributed equally to this workAbstract: Targeting of the vascular endothelium compartment explains, in part, the therapeutic efficacy of the nonselective β-adrenergic antagonist propranolol against common endothelial tumors such as hemangiomas. In vitro, the antiangiogenic biological activity of propranolol was shown to inhibit human brain microvascular endothelial cell tubulogenesis. However, possible interference of propranolol with cell signaling associated with the tumoral compartment remains unexplored. We therefore assessed the potency of propranolol against a pediatric brain tumor-derived DAOY medulloblastoma cell model. Gene expression of β1-, β2-, and β3-adrenergic receptors was confirmed in DAOY cells by semiquantitative RT-PCR. We next found that propranolol dose-dependently inhibited induction of the key extracellular matrix-degrading and blood–brain barrier disrupting enzyme matrix metalloproteinase-9 (MMP-9 by phorbol 12-myristate 13-acetate (PMA. Propranolol not only inhibited PMA-induced phosphorylation of the extracellular signal-regulated kinase (Erk, but also that of IkappaB (IκB, preventing the IκB phosphorylation which is a prerequisite for IκB degradation. Propranolol inhibition of IκB phosphorylation was shown to occur with optimal efficacy at 30 µM. Although propranolol, at up to 100 µM, did not affect cell viability, it potentiated PMA-mediated signaling that ultimately led to diminished phosphorylation of Akt. The anti-Erk and anti-Akt phosphorylation effects are both suggestive of antiproliferative and antisurvival signaling, respectively. Our data are

  17. Activation of alpha(2)-adrenergic receptors impairs exercise-induced lipolysis in SCAT of obese subjects.

    Science.gov (United States)

    Stich, V; De Glisezinski, I; Crampes, F; Hejnova, J; Cottet-Emard, J M; Galitzky, J; Lafontan, M; Rivière, D; Berlan, M

    2000-08-01

    With the use of the microdialysis method, exercise-induced lipolysis was investigated in subcutaneous adipose tissue (SCAT) in obese subjects and compared with lean ones, and the effect of blockade of alpha(2)-adrenergic receptors (ARs) on lipolysis during exercise was explored. Changes in extracellular glycerol concentrations and blood flow were measured in SCAT in a control microdialysis probe at rest and during 60-min exercise bouts (50% of heart rate reserve) and in a probe supplemented with the alpha(2)-AR antagonist phentolamine. At rest and during exercise, plasma norepinephrine and epinephrine concentrations were not different in obese compared with lean men. In the basal state, plasma and extracellular glycerol concentrations were higher, whereas blood flow was lower in SCAT of obese subjects. During exercise, the increase of plasma glycerol was higher in obese subjects (115 +/- 35 vs. 65 +/- 21 micromol/l). Oppositely, the exercise-induced increase in extracellular glycerol concentrations in SCAT was five- to sixfold lower in obese than in lean subjects (50 +/- 14 vs. 318 +/- 53 micromol/l). The exercise-induced increase in extracellular glycerol concentration was not significantly modified by phentolamine infusion in lean subjects but was strongly enhanced in the obese subjects and reached the concentrations found in lean sujects (297 +/- 46 micromol/l). These findings demonstrate that the physiological stimulation of SCAT adipocyte alpha(2)-ARs during exercice-induced sympathetic nervous system activation contributes to the blunted lipolysis noted in obese men.

  18. Gender-related differences in β-adrenergic receptor-mediated cardiac remodeling.

    Science.gov (United States)

    Zhu, Baoling; Liu, Kai; Yang, Chengzhi; Qiao, Yuhui; Li, Zijian

    2016-12-01

    Cardiac remodeling is the pathological basis of various cardiovascular diseases. In this study, we found gender-related differences in β-adrenergic receptor (AR)-mediated pathological cardiac remodeling. Cardiac remodeling model was established by subcutaneous injection of isoprenaline (ISO) for 14 days. Heart rate (HR), mean arterial pressure (MAP), and echocardiography were obtained on 7th and 14th days during ISO administration. Myocardial cross-sectional area and the ratio of heart mass to tibia length (HM/TL) were detected to assess cardiac hypertrophy. Picro-Sirius red staining (picric acid + Sirius red F3B) was used to evaluate cardiac fibrosis. Myocardial capillary density was assessed by immunohistochemistry for von Willebrand factor. Further, real-time PCR was used to measure the expression of β1-AR and β2-AR. Results showed that ISO induced cardiac remodeling, the extent of which was different between female and male mice. The extent of increase in cardiac wall thickness, myocardial cross-sectional area, and collagen deposition in females was less than that in males. However, no gender-related difference was observed in HR, MAP, cardiac function, and myocardial capillary density. The distinctive decrease of β2-AR expression, rather than a decrease of β1-AR expression, seemed to result in gender-related differences in cardiac remodeling.

  19. 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.

  20. Research on Autoantibodies Against Myocardial β1-adrenergic and M2 Cholinergic Receptors in Patients With Chronic Keshan Disease

    Institute of Scientific and Technical Information of China (English)

    Han Zhenhua; Niu Xiaolin; Ren Fuxian

    2006-01-01

    Objectives To explore the relationship between serum autoantibodies against myocardial β1-adrenergic, M2-cholinergic receptors and chronic Keshan disease (CKD). Methods The second extracellular loops of β1 and M2 receptors on human cardiomyocytes were used as the antigens.Enzyme linked immunosorbent assay (ELISA) was applied to determine serum autoantibodies against myocardial β1 and M2 receptors in 32 CKD patients. 31 healthy subjects from endemic area were selected as the control. Results Positive rate of autoantibodies against myocardial β1 adrenergic (51.3%, 17/32) and M2cholinergic (56.3% , 18/32) receptors weresignificantly higher than those in the control (9.7%, 3/31; 12.9%, 4/31) (both P < 0.01). Both positive rate and titers of above autoantibodies in NYHA Ⅱ~Ⅲ CKD patients were significantly higher than those in NYHA Ⅳ , demonstrating an apparently positive correlation between serum antibodies against myocardial β1 and M2 receptors (r=0.95). Conclusions Autoantibodies against myocardial β1 and M2 receptors were found in sera of CKD patients; distribution of positive rate and titers of the autoantibodies in CKD patients in various NYHA classes of cardiac function are significantly different.

  1. The Gly16 Allele of the Gly16Arg Single-Nucleotide Polymorphism in the β2-Adrenergic Receptor Gene Augments Perioperative Use of Vasopressors

    DEFF Research Database (Denmark)

    Nielsen, Morten; Staalsø, Jonatan Myrup; Ullum, Henrik

    2016-01-01

    receptor (ADRB2) influences perioperative arterial blood pressure and consequently the use of vasopressors. METHODS: Five hundred seventy-one Danish Caucasians undergoing neurosurgery were genotyped for 5 marker single-nucleotide polymorphisms (SNPs) within ADRB2 (Gly16Arg, Gln27Glu, Thr164Ile, Arg175Arg......, and Gly351Gly). A pairwise tagging principle was used to identify ADRB2 haplotypes. Mean arterial blood pressure (MAP) was recorded in the supine awake state and, together with administration of vasopressors (ephedrine and/or phenylephrine), for 30 minutes after induction of general anesthesia...... (sevoflurane/remifentanil or propofol/remifentanil). RESULTS: Four hundred thirteen (72%) patients received ephedrine and/or phenylephrine. Only baseline MAP (P

  2. Two distinct conformations of helix 6 observed in antagonist-bound structures of a β1-adrenergic receptor

    OpenAIRE

    2011-01-01

    The β1-adrenergic receptor (β1AR) is a G-protein-coupled receptor whose inactive state structure was determined using a thermostabilized mutant (β1AR–M23). However, it was not thought to be in a fully inactivated state because there was no salt bridge between Arg139 and Glu285 linking the cytoplasmic ends of transmembrane helices 3 and 6 (the R3.50 - D/E6.30 “ionic lock”). Here we compare eight new structures of β1AR–M23, determined from crystallographically independent molecules in four diff...

  3. Coupling of lipolysis and de novo lipogenesis in brown, beige, and white adipose tissues during chronic β3-adrenergic receptor activation.

    Science.gov (United States)

    Mottillo, Emilio P; Balasubramanian, Priya; Lee, Yun-Hee; Weng, Changren; Kershaw, Erin E; Granneman, James G

    2014-11-01

    Chronic activation of β3-adrenergic receptors (β3-ARs) expands the catabolic activity of both brown and white adipose tissue by engaging uncoupling protein 1 (UCP1)-dependent and UCP1-independent processes. The present work examined de novo lipogenesis (DNL) and TG/glycerol dynamics in classic brown, subcutaneous "beige," and classic white adipose tissues during sustained β3-AR activation by CL 316,243 (CL) and also addressed the contribution of TG hydrolysis to these dynamics. CL treatment for 7 days dramatically increased DNL and TG turnover similarly in all adipose depots, despite great differences in UCP1 abundance. Increased lipid turnover was accompanied by the simultaneous upregulation of genes involved in FAS, glycerol metabolism, and FA oxidation. Inducible, adipocyte-specific deletion of adipose TG lipase (ATGL), the rate-limiting enzyme for lipolysis, demonstrates that TG hydrolysis is required for CL-induced increases in DNL, TG turnover, and mitochondrial electron transport in all depots. Interestingly, the effect of ATGL deletion on induction of specific genes involved in FA oxidation and synthesis varied among fat depots. Overall, these studies indicate that FAS and FA oxidation are tightly coupled in adipose tissues during chronic adrenergic activation, and this effect critically depends on the activity of adipocyte ATGL.

  4. Involvement of adrenergic and serotonergic receptors in antidepressant-like effect of urocortin 3 in a modified forced swimming test in mice.

    Science.gov (United States)

    Tanaka, Masaru; Telegdy, Gyula

    2008-11-25

    Most of the evidence suggests that peptides in the corticotropin-releasing factor (CRF) family act on CRF receptors and are involved in depressive disorders. Urocortin 3 (Ucn 3) is specific for CRF type 2 (CRF(2)) receptors and mediates anxiolytic-like action. Little is known about the roles of Ucn 3 and CRH(2) receptors on depressive disorders. The previous study revealed that Ucn 3 elicits the antidepressant-like action by shortening the immobility time and increasing both the climbing time and the swimming time. The involvement of the adrenergic and serotonergic receptors in the antidepressant-like effect of Ucn 3 (0.5μg/2μl, i.c.v.) was studied in a modified forced swimming test (FST) in mice. Mice were pretreated with a non-selective α-adrenergic receptor antagonist, phenoxybenzamine, an α(1)/α(2β)-adrenergic receptor antagonist, prazosin, an α(2)-adrenergic receptor antagonist, yohimbine, a mixed 5-HT(1)/5-HT(2) serotonergic receptor antagonist, methysergide, a non-selective 5-HT(2) serotonergic receptor antagonist, cyproheptadine or a β-adrenergic receptor antagonist, propranolol. Phenoxybenzamine prevented the effects of Ucn 3 on the immobility time. Prazosin prevented the effects of Ucn 3 on the climbing time. Yohimbine prevented the effects of Ucn 3 on the immobility, climbing and swimming times. Methysergide prevented the effects of Ucn 3 on the immobility and climbing time. Cyproheptadine prevented the effects of Ucn 3 on the swimming time. Propranolol did not change the effects of Ucn 3. The results demonstrated that the antidepressant-like effect of Ucn 3 is mediated, at least in part, by an interaction of the α-adrenergic and serotonergic receptors in a modified mouse FST.

  5. Meta-analysis of the association between Trp64Arg polymorphism in β3-adrenergic receptor gene and overweight/obesity in children%儿童超重/肥胖与β3肾上腺素受体基因Trp64 Arg多态性的关联meta分析

    Institute of Scientific and Technical Information of China (English)

    吴静; 焦周阳; 张静; 罗强; 刘玉峰; 安金斗; 田培超; 张好好

    2016-01-01

    [Summary] In this study, PubMed, Embase, China National Knowledge Infrastructure, databases VIP Chinese Periodical Database, and Wanfang Chinese Periodical Database were systematically searched for the case-control study related β3-adrenergic receptor ( ADRB3 ) Trp64Arg gene polymorphism to overweight/obesity among children from 1962 to 2014.Twelve eligible studies with 2 222 overweight/obese children and 1 955 normal children were included according the uniform inclusion and exclusion criteria.Meta-analyses showed that Trp64Arg polymorphism was associated with significantly increased overweight/obesity risk in Arg carriers among children( OR=1.34,95%CI1.17-1.53).Afterstratificationforethnicity,highlysignificantcoorelationofTrp64Argpolymorphism to overweight/obesity in Asian children(OR=1.44, 95%CI 1.23-1.68) but not significant in Europe(OR=1.05, 95%CI 0.79-1.40).It suggested that Trp64Arg polymorphism is associated with overweight/obesity susceptibility in children.Our results support an strong association between Trp64Arg polymorphism and overweight/obesity among the Asian children investigated.%本研究通过计算机检索Pubmed、Embae、中国全文期刊数据库(包含博硕士论文数据库)、万方和维普中文科技期刊数据库,收集1962年至2014年β3肾上腺素受体(β3-adrenergic receptor, ADRB3)基因Trp64Arg多态性与儿童超重/肥胖的病例对照研究文献,共纳入12篇文献,其中儿童超重/肥胖者2222例,对照组1955人。 Meta分析结果显示,ADRΒ3基因Trp64Arg突变能够增加儿童超重/肥胖的发病风险(OR=1.34,95%CI 1.17~1.53),亚洲儿童中该基因突变型携带者超重/肥胖风险升高明显(OR=1.44,95%CI 1.23~1.68),欧洲儿童Arg携带者罹患超重/肥胖风险升高不明显(OR=1.05,95%CI 0.79~1.40)。提示β3肾上腺素受体基因Trp64Arg多态性与儿童超重/肥胖发病具有一定相关性

  6. Activation of a GTP-binding protein and a GTP-binding-protein-coupled receptor kinase (beta-adrenergic-receptor kinase-1) by a muscarinic receptor m2 mutant lacking phosphorylation sites.

    Science.gov (United States)

    Kameyama, K; Haga, K; Haga, T; Moro, O; Sadée, W

    1994-12-01

    A mutant of the human muscarinic acetylcholine receptor m2 subtype (m2 receptor), lacking a large part of the third intracellular loop, was expressed and purified using the baculovirus/insect cell culture system. The mutant was not phosphorylated by beta-adrenergic-receptor kinase, as expected from the previous assignment of phosphorylation sites to the central part of the third intracellular loop. However, the m2 receptor mutant was capable of stimulating beta-adrenergic-receptor-kinase-1-mediated phosphorylation of a glutathione S-transferase fusion protein containing the m2 phosphorylation sites in an agonist-dependent manner. Both mutant and wild-type m2 receptors reconstituted with the guanine-nucleotide-binding regulatory proteins (G protein), G(o) and G(i)2, displayed guanine-nucleotide-sensitive high-affinity agonist binding, as assessed by displacement of [3H]quinuclidinyl-benzilate binding with carbamoylcholine, and both stimulated guanosine 5'-3-O-[35S]thiotriphosphate ([35S]GTP[S]) binding in the presence of carbamoylcholine and GDP. The Ki values of carbamoylcholine effects on [3H]quinuclidinyl-benzilate binding were indistinguishable for the mutant and wild-type m2 receptors. Moreover, the phosphorylation of the wild-type m2 receptor by beta-adrenergic-receptor kinase-1 did not affect m2 interaction with G proteins as assessed by the binding of [3H]quinuclidinyl benzilate or [35S]GTP[S]. These results indicate that (a) the m2 receptor serves both as an activator and as a substrate of beta-adrenergic-receptor kinase, and (b) a large part of the third intracellular loop of the m2 receptor does not contribute to interaction with G proteins and its phosphorylation by beta-adrenergic-receptor kinase does not uncouple the receptor and G proteins in reconstituted lipid vesicles.

  7. Yeast two-hybrid screening for proteins that interact with α1-adrenergic receptors

    Institute of Scientific and Technical Information of China (English)

    TanZHANG; QiXU; Feng-rongCHEN; Qi-deHAN; You-yiZHANG

    2004-01-01

    AIM: To find novel proteins that may bind to α1A-adrenergic receptor (α1A-AR) and investigate their interactions with the other two α1-AR subtypes (α1B-AR and α1D-AR) with an expectation to provide new leads for the function study of the receptors. METHODS: Yeast two-hybrid assay was performed to screen a human brain cDNA library using the C terminus of α1A-AR (α1A-AR-CT) as bait. X-Gal assay and o-nitrophenyl-beta-D-galactopyranoside (ONPG) assay were subsequently conducted to further qualitatively or quantitatively confirm the interactions between receptors and the three identified proteins. RESULTS: (1) Selection medium screening identified segments of bone morphogenetic protein-1 (BMP-1), active Bcr-related protein (Abr), and filamin-C as binding partners of α1A-AR-CT in yeast cells respectively. Besides, protein segments of BMP-1 and Abr could only specifically interact with α1A-AR-CT while filamin-C segment interacted with all three α1-AR subtypes. (2) In X-Gal assay, the cotransformants of α1A-AR-CT and BMP-1 segments turned strong blue at about 30 min while other positive transformants only developed weak blue at about 5-6 h. (3) In ONPG assay, interaction (shown in β-galactosidase activity) between α1A-AR-CT and BMP-1 segments was about 30 times stronger than that of control (P<0.01), while other positive interactions were only about 2-5 times as strong as those of controls (P<0.05). CONCLUSION: In yeast cells BMP-1, Abr and/or filamin-C could interact with three α1-AR subtypes, among which, interaction between BMP-1 and α1A-AR was the strongest while other interactions between proteins and receptors were relatively weak.

  8. Yeast two-hybrid screening for proteins that interact with α1-adrenergic receptors

    Institute of Scientific and Technical Information of China (English)

    Tan ZHANG; Qi XU; Feng-rong CHEN; Qi-de HAN; You-yi ZHANG

    2004-01-01

    AIM: To find novel proteins that may bind to α1A-adrenergic receptor (α1A-AR) and investigate their interactions with the other two α1-AR subtypes (α1B-AR and α1D-AR) with an expectation to provide new leads for the function study of the receptors. METHODS: Yeast two-hybrid assay was performed to screen a human brain cDNA library using the C terminus of α1A-AR (α1A-AR-CT) as bait. X-Gal assay and o-nitrophenyl-beta-D-galactopyranoside(ONPG) assay were subsequently conducted to further qualitatively or quantitatively confirm the interactions between receptors and the three identified proteins. RESULTS: (1) Selection medium screening identified segments of bone morphogenetic protein-1 (BMP-1), active Bcr-related protein (Abr), and filamin-C as binding partners ofα1A-AR-CT in yeast cells respectively. Besides, protein segments of BMP-1 and Abr could only specifically interact with α1A-AR-CT while filamin-C segment interacted with all three α1-AR subtypes. (2) In X-Gal assay, the cotransformants of α1A-AR-CT and BMP-1 segments turned strong blue at about 30 min while other positive transformants only developed weak blue at about 5-6 h. (3) In ONPG assay, interaction (shown in β-galactosidase activity) between α1A-AR-CT and BMP-1 segments was about 30 times stronger than that of control (P<0.01),while other positive interactions were only about 2-5 times as strong as those of controls (P<0.05). CONCLUSION:In yeast cells BMP-1, Abr and/or filamin-C could interact with three α1-AR subtypes, among which, interaction between BMP-1 and α1A-AR was the strongest while other interactions between proteins and receptors were relatively weak.

  9. Cardiac β2-Adrenergic Receptor Phosphorylation at Ser355/356 Regulates Receptor Internalization and Functional Resensitization.

    Science.gov (United States)

    Fan, Xiaofang; Gu, Xuejiang; Zhao, Ru; Zheng, Qingqing; Li, Lan; Yang, Wenbing; Ding, Lu; Xue, Feng; Fan, Junming; Gong, Yongsheng; Wang, Yongyu

    2016-01-01

    Previous studies have demonstrated that β2-adrenergic receptors (β2ARs) can be phosphorylated by G protein-coupled receptor kinases (GRKs) and protein kinase A (PKA), affecting β2AR internalization and desensitization. However, the exact physiological function of β2ARs in cardiomyocytes is unknown. In this study, we showed that neonatal mouse cardiomyocytes had different contraction and internalization responses to sustained or repeated, transient agonist stimulation. Specifically, short-time stimulation (10 min) with epinephrine or norepinephrine increased the cardiomyocyte contraction rate, reaching a maximum at 5 min, followed by a slow decline. When the agonist was re-added after a 60-min wash-out period, the increase in the cardiomyocyte contraction rate was similar to the initial response. In contrast, when cardiomyocytes were exposed continuously to epinephrine or norepinephrine for 60 min, the second agonist stimulation did not increase the contraction response. These results indicated that continuous β2AR stimulation caused functional desensitization. Phosphorylation of β2ARs at serine (Ser)355/356 GRK phosphorylation sites, but not at Ser345/346 PKA phosphorylation sites increased with continuous epinephrine stimulation for 60 min. Accordingly, β2AR internalization increased. Interestingly, β2AR internalization was blocked by mutations at the GRK phosphorylation sites, but not by mutations at the PKA phosphorylation sites. Furthermore, inhibition of β2AR dephosphorylation by okadaic acid, a phosphatase 2A inhibitor, impaired the recovery of internalized β2ARs and reduced the cardiomyocyte contraction rate in response to epinephrine. Finally, epinephrine treatment induced the physical interaction of β-arrestin with internalized β2ARs in cardiomyocytes. Together, these data revealed the essential role of the Ser355/356 phosphorylation status of β2ARs in regulating receptor internalization and physiological resensitization in neonatal

  10. 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

    Directory of Open Access Journals (Sweden)

    Luong KV

    2012-12-01

    Full Text Available Khanh vinh quốc Lương, Lan Thi Hoàng NguyễnVietnamese American Medical Research Foundation, Westminster, California, USAAbstract: 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.Keywords: β-adrenergic blocker, neoplasm, β-adrenergic antagonism, non-genomic factor

  11. Impaired desensitization of a human polymorphic α2B-adrenergic receptor variant enhances its sympatho-inhibitory activity in chromaffin cells

    Directory of Open Access Journals (Sweden)

    Lymperopoulos Anastasios

    2011-02-01

    Full Text Available Abstract Background α2-adrenergic receptors (ARs mediate many cellular actions of epinephrine and norepinephrine and inhibit their secretion from adrenal chromaffin cells. Like many other G-protein coupled receptors (GPCRs, they undergo agonist-dependent phopshorylation and desensitization by GPCR Kinases (GRKs, a phenomenon recently shown to play a major role in the sympathetic overdrive that accompanies and aggravates chronic heart failure. A deletion polymorphism in the human α2B-AR gene (Glu301-303 causes impaired agonist-promoted receptor phosphorylation and desensitization in heterologous cell lines. Given the importance of α2-ARs in regulation of catecholamine secretion from chromaffin cells, we sought to investigate, in the present study, the desensitization properties and the sympatho-inhibitory activity of this variant in a chromaffin cell line. For this purpose, we expressed this variant and its wild type counterpart in the well-established chromaffin cell line PC12, and performed receptor phosphorylation and desensitization studies, as well as in vitro catecholamine secretion assays. Results Both the agonist-induced phosphorylation and agonist-dependent desensitization of the human Glu301-303 deletion polymorphic α2B-AR are significantly impaired in PC12 cells, resulting in enhanced signaling to inhibition of cholinergic-induced catecholamine secretion in vitro. Conclusion This α2B-AR gene polymorphism (Glu301-303 deletion might confer better protection against conditions characterized and aggravated by sympathetic/catecholaminergic overstimulation in vivo.

  12. Prognostic significance of β2-adrenergic receptor expression in malignant melanoma.

    Science.gov (United States)

    Shimizu, Akira; Kaira, Kyoichi; Mori, Keita; Kato, Madoka; Shimizu, Kimihiro; Yasuda, Masahito; Takahashi, Ayumi; Oyama, Tetsunari; Asao, Takayuki; Ishikawa, Osamu

    2016-05-01

    Recent studies cite β2-adrenergic receptor (β2AR) antagonists as novel therapeutic agents for melanoma, as they may reduce the disease progression. The β2AR has shown to be expressed in malignant melanoma. However, it remains unclear whether the β2AR expression has a clinical and pathological significance in patients with cutaneous malignant melanoma. We herein conducted a clinicopathological study to investigate the protein expression of β2AR in malignant melanoma of the skin and its prognostic significance. One hundred thirty-three patients with surgically resected cutaneous malignant melanoma were evaluated. Tumor sections were stained by immunohistochemistry for β2AR, Ki-67, the microvessel density (MVD) determined by CD34, and p53. β2AR was highly expressed in 44.4 % (59 out of 133) of the patients. The expression of β2AR was significantly associated with the tumor thickness, ulceration, T factor, N factor, disease stage, tumor size, cell proliferation (Ki-67), and MVD (CD34). Using Spearman's rank test, the β2AR expression was correlated with Ki-67 (r = 0.278; 95 % CI, 0.108 to 0.432; P = 0.001), CD34 (r = 0.445; 95 %CI, 0.293 to 0.575; P melanoma of the skin. β2AR can serve as a promising prognostic factor for predicting a worse outcome after surgical treatment and may play an important role in the development and aggressiveness of malignant melanoma.

  13. β-Adrenergic receptor subtype signaling in heart:From bench to bedside

    Institute of Scientific and Technical Information of China (English)

    Anthony Yiu Ho WOO; Rui-ping XIAO

    2012-01-01

    β-Adrenergic receptor (βAR) stimulation by the sympathetic nervous system or circulating catecholamines is broadly involved in peripheral blood circulation,metabolic regulation,muscle contraction,and central neural activities.In the heart,acute βAR stimulation serves as the most powerful means to regulate cardiac output in response to a fight-or-flight situation,whereas chronic βAR stimulation plays an important role in physiological and pathological cardiac remodeling.There are three βAR subtypes,β1AR,β2AR and β3AR,in cardiac myocytes.Over the past two decades,we systematically investi-gated the molecular and cellular mechanisms underlying the different even opposite functional roles of β1AR and β2AR subtypes in regulating cardiac structure and function,with keen interest in the development of novel therapies based on our discoveries.We have made three major discoveries,including (1) dual coupling of β2AR to Gs and Gi proteins in cardiomyocytes,(2) cardioprotection by β2AR signaling in improving cardiac function and myocyte viability,and (3) PKA-independent,CaMKII-mediated β1AR apoptotic and maladaptive remodeling signaling in the heart.Based on these discoveries and salutary effects of β1AR blockade on patients with heart failure,we envision that activation of β2AR in combination with clinically used β1AR blockade should provide a safer and more effective therapy for the treatment of heart failure.

  14. ß-Adrenergic Receptor Signaling and Modulation of Long-Term Potentiation in the Mammalian Hippocampus

    Science.gov (United States)

    O'Dell, Thomas J.; Connor, Steven A.; Guglietta, Ryan; Nguyen, Peter V.

    2015-01-01

    Encoding new information in the brain requires changes in synaptic strength. Neuromodulatory transmitters can facilitate synaptic plasticity by modifying the actions and expression of specific signaling cascades, transmitter receptors and their associated signaling complexes, genes, and effector proteins. One critical neuromodulator in the…

  15. β2-Adrenergic receptor agonists activate CFTR in intestinal organoids and subjects with cystic fibrosis

    NARCIS (Netherlands)

    Vijftigschild, Lodewijk A W; Berkers, Gitte; Dekkers, Johanna F; Zomer-van Ommen, Domenique D; Matthes, Elizabeth; Kruisselbrink, Evelien; Vonk, Annelotte; Hensen, Chantal E; Heida-Michel, Sabine; Geerdink, Margot; Janssens, Hettie M; van de Graaf, Eduard A; Bronsveld, Inez; de Winter-de Groot, Karin M; Majoor, Christof J; Heijerman, Harry G M; de Jonge, Hugo R; Hanrahan, John W; van der Ent, Cornelis K; Beekman, Jeffrey M

    2016-01-01

    We hypothesized that people with cystic fibrosis (CF) who express CFTR (cystic fibrosis transmembrane conductance regulator) gene mutations associated with residual function may benefit from G-protein coupled receptor (GPCR)-targeting drugs that can activate and enhance CFTR function.We used intesti

  16. Exercício físico, receptores β-adrenérgicos e resposta vascular Physical exercise, β-adrenergic receptors, and vascular response

    Directory of Open Access Journals (Sweden)

    Alexandre Sérgio Silva

    2010-06-01

    Full Text Available O exercício aeróbio promove efeitos benéficos na prevenção e tratamento de doenças como hipertensão arterial, aterosclerose, insuficiência venosa e doença arterial periférica. Os receptores β-adrenérgicos estão presentes em várias células. No sistema cardiovascular, promovem inotropismo e cronotropismo positivo cardíaco e relaxamento vascular. Embora os efeitos do exercício tenham sido investigados em receptores cardíacos, estudos focados nos vasos são escassos e controversos. Esta revisão abordará os efeitos do exercício físico sobre os receptores β-adrenérgicos vasculares em modelos animais e humanos e os mecanismos celulares envolvidos na resposta relaxante. Em geral, os estudos mostram resultantes conflitantes, onde observam diminuição, aumento ou nenhum efeito do exercício físico sobre a resposta relaxante. Assim, os efeitos do exercício na sensibilidade β-adrenérgica vascular merecem maior atenção, e os resultados mostram que a área de fisiopatologia vascular é um campo aberto para a descoberta de novos compostos e avanços na prática clínica.Aerobic exercise promotes beneficial effects on the prevention and treatment of diseases such as arterial hypertension, atherosclerosis, venous insufficiency, and peripheral arterial disease. β-adrenergic receptors are present in a variety of cells. In the cardiovascular system, β-adrenergic receptors promote positive inotropic and chronotropic response and vasorelaxation. Although the effect of exercise training has been largely studied in the cardiac tissue, studies focused on the vascular tissue are rare and controversial. This review examines the data from studies using animal and human models to determine the effect of physical exercise on the relaxing response mediated by β-adrenergic receptors as well as the cellular mechanisms involved in this response. Studies have shown reduction, increase, or no effect of physical exercise on the relaxing response

  17. Association analysis of the beta-3 adrenergic receptor Trp64Arg (rs4994) polymorphism with urate and gout.

    Science.gov (United States)

    Fatima, Tahzeeb; Altaf, Sara; Phipps-Green, Amanda; Topless, Ruth; Flynn, Tanya J; Stamp, Lisa K; Dalbeth, Nicola; Merriman, Tony R

    2016-02-01

    The Arg64 allele of variant rs4994 (Trp64Arg) in the β3-adrenergic receptor gene has been associated with increased serum urate and risk of gout. Our objective was to investigate the relationship of rs4994 with serum urate and gout in New Zealand European, Māori and Pacific subjects. A total of 1730 clinically ascertained gout cases and 2145 controls were genotyped for rs4994 by Taqman(®). Māori and Pacific subjects were subdivided into Eastern Polynesian (EP) and Western Polynesian (WP) sample sets. Publicly available genotype data from the Atherosclerosis Risk in Communities Study and the Framingham Heart Study were utilized for serum urate association analysis. Multivariate logistic and linear regression adjusted for potential confounders was carried out using R version 2.15.2. No significant association of the minor Arg64 (G) allele of rs4994 with gout was found in the combined Polynesian cohorts (OR = 0.98, P = 0.88), although there was evidence, after adjustment for renal disease, for association in both the WP (OR = 0.53, P = 0.03) and the lower Polynesian ancestry EP sample sets (OR = 1.86, P = 0.05). There was no evidence for association with gout in the European sample set (OR = 1.11, P = 0.57). However, the Arg64 allele was positively associated with urate in the WP data set (β = 0.036, P = 0.004, P Corrected = 0.032). Association of the Arg64 variant with increased urate in the WP sample set was consistent with the previous literature, although the protective effect of this variant with gout in WP was inconsistent. This association provides an etiological link between metabolic syndrome components and urate homeostasis.

  18. p-( sup 125 I)iodoclonidine, a novel radiolabeled agonist for studying central alpha 2-adrenergic receptors

    Energy Technology Data Exchange (ETDEWEB)

    Baron, B.M.; Siegel, B.W. (Merrell Dow Research Institute, Cincinnati, OH (USA))

    1990-09-01

    Unlabeled p-iodoclonidine was efficacious in attenuating forskolin-stimulated cAMP accumulation in SK-N-SH neuroblastoma cells. Maximal attenuation was 76 +/- 3%, with an EC50 of 347 +/- 60 nM. Comparable values of epinephrine were 72 +/- 3% and 122 +/- 22 nM. Responses to both agonists were abolished by 10 microM phentolamine. Therefore, p-iodoclonidine is an agonist in a cell culture model system of the neuronal alpha 2-adrenergic receptor. p-(125I)Iodoclonidine binding to membranes were measured using various regions of the rat brain. The agonist labeled a single population of sites present on cerebral cortical membranes, which was saturable (Bmax = 230 fmol/mg of protein) and possessed high affinity for the ligand (Kd = 0.6 nM). Binding was largely specific (93% at 0.6 nM). A variety of alpha 2-adrenergic agonists and antagonists were shown to compete for the binding of the radioligand. The binding of p-(125I)iodoclonidine was much less sensitive to agents that interact with alpha 1-adrenergic, serotonergic, and dopaminergic receptors. Approximately 65% of the binding was sensitive to guanine nucleotides. Association kinetics using 0.4 nM radioligand were biphasic (37% associate rapidly, with kobs = 0.96 min-1, with the remainder binding more slowly, with kobs = 0.031 min-1) and reached a plateau by 90 min at 25 degrees. Dissociation kinetics were also biphasic, with 30% of the binding dissociating rapidly (k1 = 0.32 min-1) and the remainder dissociating 50-fold more slowly (k2 = 0.006 min-1). Agonist binding is, therefore, uniquely complex and probably reflects the conformational changes that accompany receptor activation.

  19. Involvement of Cholinergic and Adrenergic Receptors in Pathogenesis and Inflammatory Response Induced by Alpha-Neurotoxin Bot III of Scorpion Venom.

    Science.gov (United States)

    Nakib, Imene; Martin-Eauclaire, Marie-France; Laraba-Djebari, Fatima

    2016-10-01

    Bot III neurotoxin is the most lethal α neurotoxin purified from Buthus occitanus tunetanus scorpion venom. This toxin binds to the voltage-gated sodium channel of excitable cells and blocks its inactivation, inducing an increased release of neurotransmitters (acetylcholine and catecholamines). This study aims to elucidate the involvement of cholinergic and adrenergic receptors in pathogenesis and inflammatory response triggered by this toxin. Injection of Bot III to animals induces an increase of peroxidase activities, an imbalance of oxidative status, tissue damages in lung parenchyma, and myocardium correlated with metabolic disorders. The pretreatment with nicotine (nicotinic receptor agonist) or atropine (muscarinic receptor antagonist) protected the animals from almost all disorders caused by Bot III toxin, especially the immunological alterations. Bisoprolol administration (selective β1 adrenergic receptor antagonist) was also efficient in the protection of animals, mainly on tissue damage. Propranolol (non-selective adrenergic receptor antagonist) showed less effect. These results suggest that both cholinergic and adrenergic receptors are activated in the cardiopulmonary manifestations induced by Bot III. Indeed, the muscarinic receptor appears to be more involved than the nicotinic one, and the β1 adrenergic receptor seems to dominate the β2 receptor. These results showed also that the activation of nicotinic receptor leads to a significant protection of animals against Bot III toxin effect. These findings supply a supplementary data leading to better understanding of the mechanism triggered by scorpionic neurotoxins and suggest the use of drugs targeting these receptors, especially the nicotinic one in order to counteract the inflammatory response observed in scorpion envenomation.

  20. The essential role for aromatic cluster in the β3 adrenergic receptor

    Institute of Scientific and Technical Information of China (English)

    Hai-yan CAI; Zhi-jian XU; Jie TANG; Ying SUN; Kai-xian CHEN; He-yao WANG; Wei-liang ZHU

    2012-01-01

    Aim:To explore the function of the conserved aromatic cluster F2135.47,F3086.51,and F3096.52 in human β3 adrenergic receptor (hβ3AR).Methods:Point mutation technology was used to produce plasmid mutations of hβ3AR.HEK-293 cells were transiently co-transfected with the hβ3AR (wild-type or mutant) plasmids and luciferase reporter vector pCRE-luc.The expression levels of hβ3AR in the cells were determined by Western blot analysis.The constitutive signalling and the signalling induced by the β3AR selective agonist,BRL (BRL37344),were then evaluated.To further explore the interaction mechanism between BRL and β3AR,a three-dimensional complex model of β3AR and BRL was constructed by homology modelling and molecular docking.Results:For F3086.51,Ala and Leu substitution significantly decreased the constitutive activities of β3AR to approximately 10% of that for the wild-type receptor.However,both the potency and maximal efficacy were unchanged by Ala substitution.In the F3086.51L construct,the EC50 value manifested as a "right shift" of approximately two orders of magnitude with an increased Emax.Impressively,the molecular pharmacological phenotype was similar to the wild-type receptor for the introduction of Tyr at position 3086.51,though the EC50 value increased by approximately five-fold for the mutant.For F3096.52,the constitutive signalling for both F3096.52A and F3096.52L constructs were strongly impaired.In the F3096.52A construct,BRL-stimulated signalling showed a normal Emax but reduced potency.Leu substitution of F3096.52 reduced both the Emax and potency.When F3096.52 was mutated to Tyr,the constitutive activity was decreased approximately three-fold,and BRL-stimulated signalling was significantly impaired.Furthermore,the double mutant (F3086.51A_F3096 52A) caused the total loss of β3AR function.The predicted binding mode between β3AR and BRL revealed that both F3086.51 and F3096.52 were in the BRL binding pocket of β3AR,while F2135.47 and W3056

  1. The effect of activation of central adrenergic receptors by clonidine on the excitability of the solitary tract neurons in cats.

    Science.gov (United States)

    Lipski, J; Solnicka, E

    1976-01-01

    The effect of i.v. administered clonidine (10-15 mug/kg) on the evoked potential recorded in the dosal part of medulla oblongata, during carotid sinus nerve stimulation, was studied in chloralose-urethane anaesthetized cats. Clonidine influenced the amplitude and configuration of the evoked potential and the changes were parallel to the blood pressure depressor response. However, the blood pressure drops, evoked by i.v. infusion of papaverine, did not influence the potential. It is concluded that the synaptic transmission from the carotid sinus nerve to the second order neurons in the solatary tract area can be modulated by the clonidine-induced activation of central adrenergic receptors.

  2. Data on Arc and Zif268 expression in the brain of the α-2A adrenergic receptor knockout mouse

    Directory of Open Access Journals (Sweden)

    Jeff Sanders

    2016-06-01

    Full Text Available The α2-adrenergic receptor (α2-AR is widely distributed in the brain with distinct roles for α2-AR subtypes (A, B and C. In this article, data are provided on Activity Regulated Cytoskeleton Associated Protein (Arc and Zif268 expression in the brain of the α2A-AR knockout (α2A-AR KO mouse. These data are supplemental to an original research article examining Arc and Zif268 expression in rats injected with the α2-AR antagonist, RX821002 (http://dx.doi.org/10.1016/j.neulet.2015.12.002. [1].

  3. 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.

  4. The potential of metabolomic analysis techniques for the characterisation of α1-adrenergic receptors in cultured N1E-115 mouse neuroblastoma cells.

    Science.gov (United States)

    Wenner, Maria I; Maker, Garth L; Dawson, Linda F; Drummond, Peter D; Mullaney, Ian

    2016-08-01

    Several studies of neuropathic pain have linked abnormal adrenergic signalling to the development and maintenance of pain, although the mechanisms underlying this are not yet fully understood. Metabolomic analysis is a technique that can be used to give a snapshot of biochemical status, and can aid in the identification of the mechanisms behind pathological changes identified in cells, tissues and biological fluids. This study aimed to use gas chromatography-mass spectrometry-based metabolomic profiling in combination with reverse transcriptase-polymerase chain reaction and immunocytochemistry to identify functional α1-adrenergic receptors on cultured N1E-115 mouse neuroblastoma cells. The study was able to confirm the presence of mRNA for the α1D subtype, as well as protein expression of the α1-adrenergic receptor. Furthermore, metabolomic data revealed changes to the metabolite profile of cells when exposed to adrenergic pharmacological intervention. Agonist treatment with phenylephrine hydrochloride (10 µM) resulted in altered levels of several metabolites including myo-inositol, glucose, fructose, alanine, leucine, phenylalanine, valine, and n-acetylglutamic acid. Many of the changes observed in N1E-115 cells by agonist treatment were modulated by additional antagonist treatment (prazosin hydrochloride, 100 µM). A number of these changes reflected what is known about the biochemistry of α1-adrenergic receptor activation. This preliminary study therefore demonstrates the potential of metabolomic profiling to confirm the presence of functional receptors on cultured cells.

  5. 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.

  6. p-( sup 125 I)iodoclonidine is a partial agonist at the alpha 2-adrenergic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, M.A.; Wade, S.M.; Neubig, R.R. (Univ. of Michigan Medical School, Ann Arbor (USA))

    1990-08-01

    The binding properties of p-(125I)iodoclonidine (( 125I)PIC) to human platelet membranes and the functional characteristics of PIC are reported. (125I)PIC bound rapidly and reversibly to platelet membranes, with a first-order association rate constant (kon) at room temperature of 8.0 +/- 2.7 x 10(6) M-1 sec-1 and a dissociation rate constant (koff) of 2.0 +/- 0.8 x 10(-3) sec-1. Scatchard plots of specific (125I)PIC binding (0.1-5 nM) were linear, with a Kd of 1.2 +/- 0.1 nM. (125I)PIC bound to the same number of high affinity sites as the alpha 2-adrenergic receptor (alpha 2-AR) full agonist (3H) bromoxidine (UK14,304), which represented approximately 40% of the sites bound by the antagonist (3H)yohimbine. Guanosine 5'-(beta, gamma-imido)triphosphate greatly reduced the amount of (125I)PIC bound (greater than 80%), without changing the Kd of the residual binding. In competition experiments, the alpha 2-AR-selective ligands yohimbine, bromoxidine, oxymetazoline, clonidine, p-aminoclonidine, (-)-epinephrine, and idazoxan all had Ki values in the low nanomolar range, whereas prazosin, propranolol, and serotonin yielded Ki values in the micromolar range. Epinephrine competition for (125I)PIC binding was stereoselective. Competition for (3H)bromoxidine binding by PIC gave a Ki of 1.0 nM (nH = 1.0), whereas competition for (3H)yohimbine could be resolved into high and low affinity components, with Ki values of 3.7 and 84 nM, respectively. PIC had minimal agonist activity in inhibiting adenylate cyclase in platelet membranes, but it potentiated platelet aggregation induced by ADP with an EC50 of 1.5 microM. PIC also inhibited epinephrine-induced aggregation, with an IC50 of 5.1 microM. Thus, PIC behaves as a partial agonist in a human platelet aggregation assay. (125I)PIC binds to the alpha 2B-AR in NG-10815 cell membranes with a Kd of 0.5 +/- 0.1 nM.

  7. The role of the alpha-adrenergic receptor in the leg vasoconstrictor response to orthostatic stress.

    NARCIS (Netherlands)

    Kooijman, M.; Rongen, G.A.P.J.M.; Smits, P.; Kuppevelt, H.J.M. van; Hopman, M.T.E.

    2009-01-01

    AIM: The prompt increase in peripheral vascular resistance, mediated by sympathetic alpha-adrenergic stimulation, is believed to be the key event in blood pressure control during postural stress. However, despite the absence of central sympathetic control of the leg vasculature, postural leg vasocon

  8. 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.

  9. Moxonidine, an antihypertensive agent, is permissive to alpha1-adrenergic receptor pathway in the rat-tail artery.

    Science.gov (United States)

    George, Oommen K; Gonzalez, Ramon R; Edwards, Lincoln P

    2004-02-01

    To investigate whether alpha1-adrenergic receptors were involved in the contractile response of tail arteries to moxonidine, isolated ring segments of tail arteries from male adult Sprague-Dawley rats were studied. Moxonidine (EC50 = 1.3 microM) and the alpha1-agonist phenylephrine (EC50 = 2.5 microM) increased tension development in the rat-tail artery similarly. The response to moxonidine (1 microM) could be blocked by both alpha1-adrenoceptor blockers prazosin (IC50 = 1 nM), and urapidil (IC50 = 14 nM), and also by alpha2-adrenoceptor blockers, yohimbine (IC50 = 49 nM) and efaroxan (IC50 = 49 nM). Combination drug treatment (urapidil and yohimbine, or yohimbine and prazosin) was more effective in blocking the contractile response to moxonidine, than treatment with prazosin or urapidil alone. Comparison of pA2 values for prazosin in the presence of moxonidine (9.35) or phenylephrine (10.2) confirm that alpha1-adrenergic receptors are involved in the contractile response of rat-tail artery to moxonidine.

  10. 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.

  11. Modeling of ligand binding to G protein coupled receptors: cannabinoid CB1, CB2 and adrenergic β 2 AR.

    Science.gov (United States)

    Latek, Dorota; Kolinski, Michal; Ghoshdastider, Umesh; Debinski, Aleksander; Bombolewski, Rafal; Plazinska, Anita; Jozwiak, Krzysztof; Filipek, Slawomir

    2011-09-01

    Cannabinoid and adrenergic receptors belong to the class A (similar to rhodopsin) G protein coupled receptors. Docking of agonists and antagonists to CB(1) and CB(2) cannabinoid receptors revealed the importance of a centrally located rotamer toggle switch and its possible participation in the mechanism of agonist/antagonist recognition. The switch is composed of two residues, F3.36 and W6.48, located on opposite transmembrane helices TM3 and TM6 in the central part of the membranous domain of cannabinoid receptors. The CB(1) and CB(2) receptor models were constructed based on the adenosine A(2A) receptor template. The two best scored conformations of each receptor were used for the docking procedure. In all poses (ligand-receptor conformations) characterized by the lowest ligand-receptor intermolecular energy and free energy of binding the ligand type matched the state of the rotamer toggle switch: antagonists maintained an inactive state of the switch, whereas agonists changed it. In case of agonists of β(2)AR, the (R,R) and (S,S) stereoisomers of fenoterol, the molecular dynamics simulations provided evidence of different binding modes while preserving the same average position of ligands in the binding site. The (S,S) isomer was much more labile in the binding site and only one stable hydrogen bond was created. Such dynamical binding modes may also be valid for ligands of cannabinoid receptors because of the hydrophobic nature of their ligand-receptor interactions. However, only very long molecular dynamics simulations could verify the validity of such binding modes and how they affect the process of activation.

  12. Anti-Brownian ELectrokinetic (ABEL) trapping of single β2-adrenergic receptors in the absence and presence of agonist

    Science.gov (United States)

    Bockenhauer, Samuel; Fuerstenberg, Alexandre; Yao, Xiao Jie; Kobilka, Brian K.; Moerner, W. E.

    2012-02-01

    The ABEL trap allows trapping of single biomolecules in solution for extended observation without immobilization. The essential idea combines fluorescence-based position estimation with fast electrokinetic feedback in a microfluidic geometry to counter the Brownian motion of a single nanoscale object, hence maintaining its position in the field of view for hundreds of milliseconds to seconds. Such prolonged observation of single proteins allows access to slow dynamics, as probed by any available photophysical observables. We have used the ABEL trap to study conformational dynamics of the β2-adrenergic receptor, a key G-protein coupled receptor and drug target, in the absence and presence of agonist. A single environment-sensitive dye reports on the receptor microenvironment, providing a real-time readout of conformational change for each trapped receptor. The focus of this paper will be a quantitative comparison of the ligandfree and agonist-bound receptor data from our ABEL trap experiments. We observe a small but clearly detectable shift in conformational equilibria and a lengthening of fluctuation timescales upon binding of agonist. In order to quantify the shift in state distributions and timescales, we apply nonparametric statistical tests to place error bounds on the resulting single-molecule distributions.

  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.; 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

  15. 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

  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. Melatonin Receptor Genes in Vertebrates

    Directory of Open Access Journals (Sweden)

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  18. Different affinity states of alpha-1 adrenergic receptors defined by agonists and antagonists in bovine aorta plasma membranes

    Energy Technology Data Exchange (ETDEWEB)

    Jagadeesh, G.; Deth, R.C.

    1987-11-01

    Evidence for a nonlinear relationship between alpha-1 adrenergic receptor occupancy and tissue responses, together with the finding of different affinity states for agonist binding, has raised the possibility of functional heterogeneity of alpha-1 adrenergic receptors. We have conducted studies to examine: 1) binding characteristics of (/sup 3/H)prazosin, 2) competition of antagonists at these sites and 3) different affinity states of the receptor for agonists and modulation of these states by 5'-guanylylimidodiphosphate (Gpp(NH)p). A plasma membrane-enriched vesicular fraction (F2; 15%/33% sucrose interphase) was prepared from the muscular medial layer of bovine thoracic aorta. (/sup 3/H)Prazosin binding was characterized by a monophasic saturation isotherm (KD = 0.116 nM, Bmax = 112 fmol/mg of protein). Antagonist displacement studies yielded a relative potency order of prazosin greater than or equal to WB4104 much greater than phentolamine greater than corynanthine greater than yohimbine greater than or equal to idazoxan greater than rauwolscine. Competition curves for unlabeled prazosin, WB4101 (2-(2,6-dimethoxyphenoxyethyl)-aminomethyl-1,4 benzodioxane) and phentolamine were shallow and were best modeled to two binding sites with picomolar and nanomolar KD values. Gpp(NH)p was without effect on antagonist affinity. Agonist (epinephrine, norepinephrine and phenylephrine) competition with (/sup 3/H)prazosin binding was biphasic with pseudo-Hill slopes less than 1.0. Binding was best described by a two-site model in which the average contribution of high affinity sites was 23% of total binding. KD values for the high affinity site ranged from 2.9 to 18 nM, and 3.9 to 5.0 microM for the low affinity site.

  19. Antagonism of Nav channels and α1-adrenergic receptors contributes to vascular smooth muscle effects of ranolazine.

    Science.gov (United States)

    Virsolvy, Anne; Farah, Charlotte; Pertuit, Nolwenn; Kong, Lingyan; Lacampagne, Alain; Reboul, Cyril; Aimond, Franck; Richard, Sylvain

    2015-12-10

    Ranolazine is a recently developed drug used for the treatment of patients with chronic stable angina. It is a selective inhibitor of the persistent cardiac Na(+) current (INa), and is known to reduce the Na(+)-dependent Ca(2+) overload that occurs in cardiomyocytes during ischemia. Vascular effects of ranolazine, such as vasorelaxation,have been reported and may involve multiple pathways. As voltage-gated Na(+) channels (Nav) present in arteries play a role in contraction, we hypothesized that ranolazine could target these channels. We studied the effects of ranolazine in vitro on cultured aortic smooth muscle cells (SMC) and ex vivo on rat aortas in conditions known to specifically activate or promote INa. We observed that in the presence of the Nav channel agonist veratridine, ranolazine inhibited INa and intracellular Ca(2+) calcium increase in SMC, and arterial vasoconstriction. In arterial SMC, ranolazine inhibited the activity of tetrodotoxin-sensitive voltage-gated Nav channels and thus antagonized contraction promoted by low KCl depolarization. Furthermore, the vasorelaxant effects of ranolazine, also observed in human arteries and independent of the endothelium, involved antagonization of the α1-adrenergic receptor. Combined α1-adrenergic antagonization and inhibition of SMCs Nav channels could be involved in the vascular effects of ranolazine.

  20. Multiresidue Method for Analysis of β Agonists in Swine Urine by Enzyme Linked Receptor Assay Based on β2 Adrenergic Receptor Expressed in HEK293 Cells.

    Directory of Open Access Journals (Sweden)

    Jian Wang

    Full Text Available A novel enzyme-linked receptor assay (ELRA based on β2-adrenergic receptor (β2-AR has been developed for rapid and high-throughput detection of β-adrenergic agonists (β-agonists in urine. Human embryonic kidney cells (HEK293 were introduced as the expression system to enhance the functionality of the recombinant β2-AR, and the attempt to detect β-agonists in swine urine using such approaches was accomplished unprecedentedly. In this article, a recombinant porcine β2-AR was produced in the inner membrane of HEK293 cells and purified from crude membrane protein by nickel-nitrilotriacetic acid affinity chromatography. After activity identification, the recombinant receptor was used in the development of direct competitive ELRA. Several parameters such as blocking buffer and blocking process were optimized and the performance of the system was determined. The IC50 concentrations of clenbuterol, salbutamol, and ractopamine were 34, 53 and 63 μg/L, and the average recovery rates were 68.2%, 60.3% and 65.5%, respectively. ELRA based on β2-AR shows a series of advantages such as safety, easy operation, and high efficiency, making it promising for the rapid screening of β-agonists in animal urine.

  1. Catecholamine stress alters neutrophil trafficking and impairs wound healing by β2-adrenergic receptor-mediated upregulation of IL-6.

    Science.gov (United States)

    Kim, Min-Ho; Gorouhi, Farzam; Ramirez, Sandra; Granick, Jennifer L; Byrne, Barbara A; Soulika, Athena M; Simon, Scott I; Isseroff, R Rivkah

    2014-03-01

    Stress-induced hormones can alter the inflammatory response to tissue injury; however, the precise mechanism by which epinephrine influences inflammatory response and wound healing is not well defined. Here we demonstrate that epinephrine alters the neutrophil (polymorphonuclear leukocyte (PMN))-dependent inflammatory response to a cutaneous wound. Using noninvasive real-time imaging of genetically tagged PMNs in a murine skin wound, chronic, epinephrine-mediated stress was modeled by sustained delivery of epinephrine. Prolonged systemic exposure of epinephrine resulted in persistent PMN trafficking to the wound site via an IL-6-mediated mechanism, and this in turn impaired wound repair. Further, we demonstrate that β2-adrenergic receptor-dependent activation of proinflammatory macrophages is critical for epinephrine-mediated IL-6 production. This study expands our current understanding of stress hormone-mediated impairment of wound healing and provides an important mechanistic link to explain how epinephrine stress exacerbates inflammation via increased number and lifetime of PMNs.

  2. Activation ofβ2-Adrenergic Receptor Induced by Three Catecholamine Agonists: a Docking and Molecular Dynamics Study

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui; DONG Li-hua; LING Bao-ping; WANG Zhi-guo; LIU Yong-jun

    2012-01-01

    We studied the activation of β2-adrenergic receptor(β2AR) by norepinephrine,epinephrine and isoproterenol using docking and molecular dynamics(MD) simulation.The simulation was done on the assumption that β2AR was surrounded with explicit water and infinite lipid bilayer membrane at body temperature.So the result should be close to that under the physiological conditions.We calculated the structure of binding sites in β2AR for the three activators.We also simulated the change of the conformation ofβ2AR in the transmembrane regions(TMs),in the molecular switches,and in the conserved DRY(Aspartic acid,Arginine and Tyrosine) motif.This study provides detailed information concerning the structure ofβ2AR during activation process.

  3. Role of alpha 1- and alpha 2-adrenergic receptors in the growth hormone and prolactin response to insulin-induced hypoglycemia in man.

    Science.gov (United States)

    Tatár, P; Vigas, M

    1984-09-01

    The effects of intravenous infusion of the nonselective alpha-adrenergic antagonist phentolamine or of the selective alpha 2-adrenergic antagonist yohimbine on growth hormone (GH), prolactin (PRL) and cortisol secretion during insulin-induced hypoglycemia were studied in 11 healthy young men. The GH response was blunted following each antagonist used, PRL secretion was higher after yohimbine and diminished after phentolamine when compared to controls. The plasma cortisol response was not influenced by either compound. In another series of experiments no effect of an oral administration of prazosin, a selective alpha 1-adrenergic antagonist, on the secretion of GH, PRL and cortisol was found in any of 7 subjects. Prazosin inhibited blood pressure increase during hypoglycemia and induced slight drowsiness and fatigue in the subjects. It is concluded that in man alpha-adrenergic stimulation of GH secretion during hypoglycemia is transmitted via alpha 2-receptors, PRL secretion is mediated via alpha 1-receptors, whereas inhibition of PRL release is mediated via alpha 2-receptors. In this experiment no effect of alpha 1- or alpha 2-blockade on cortisol response to hypoglycemia was seen.

  4. Association of β3 Adrenergic Receptor and Peroxisome Proliferator-activated Receptor Gamma 2 Polymorphisms With Insulin Sensitivity: A Twin Study

    Institute of Scientific and Technical Information of China (English)

    TIAN-JIAO CHEN; CHENG-YE JI; XIAO-YING ZHENG; YONG-HUA HU

    2007-01-01

    Objective To study the effect of β3 adrenergic receptor (β3AR) Trp64Arg and peroxisome proliferator activated receptor gamma 2 (PPARγ2) Pro12Ala polymorphisms on insulin resistance. Methods One hundred and eight dizygotic twin pairs were enrolled in this study. Microsatellite polymorphism was used to diagnose zygosity of twins. Insulin sensitivity was estimated with logarithm transformed homeostasis model assessment (HOMA). PCR-RFLP analysis was performed to detect the variants. As a supplement to the sib-pair method, identity by state (IBS) was used to analyze the association of polymorphisms with insulin sensitivity. Results The genotype frequencies of Trp64Trg, Trp64Arg, and Arg64Arg were 72.3%, 23.8%, and 3.9%, respectively, while the genotype frequencies of Pro12Pro, Pro12Ala, and Ala12Ala were 89.9%, 9.6%,and 0.5%, respectively. For β3AR Trp64Arg the interclass co-twin correlations of Waist-to-hip ratio (WHR), blood glucose (GLU), and insulin (INS), homeostasis model assessment insulin resistance index (HOMA-IR) of the twin pairs sharing 2alleles of IBS were greater than those sharing 0-1 allele of IBS, and HOMA-IR had statistic significance. For PPARγ2 Pro12Ala most traits of twin pairs sharing 2 alleles of IBS had greater correlations and statistic significance in body mass index (BMI),WHR, percent of body fat (PBF) and GLU, but there were low correlations of either insulin or HOMA-IR of twin pairs sharing 1 or 2 alleles of IBS. The combined effects of the two variations showed less squared significant twin-pair differences of INS and HOMA-IR among twins sharing 4 alleles of IBS. Conclusions β3AR Trp64Arg and PPARγ2 Pro12Ala polymorphisms might be associated with insulin resistance and obesity, and there might be slight synergistic effects between this two gene loci,and further studies are necessary to confirm this finding.

  5. 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.

  6. 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.

  7. Transient elevation of amygdala alpha 2 adrenergic receptor binding sites during the early stages of amygdala kindling.

    Science.gov (United States)

    Chen, M J; Vigil, A; Savage, D D; Weiss, G K

    1990-03-01

    Enhanced noradrenergic neurotransmission retards but does not prevent the development of kindling. We previously reported that locus coeruleus (LC) alpha 2 adrenergic receptor binding sites are transiently elevated during the early stages of kindling development. Since the firing activity of LC noradrenergic neurons is partially regulated via an alpha 2 receptor-mediated recurrent inhibition, the transient elevation in LC alpha 2 receptors could decrease LC activity and consequently facilitate the development of kindling. Transient elevation of alpha 2 receptor binding sites during early stages of kindling may also occur on noradrenergic axon terminals projecting to forebrain sites. Using in vitro neurotransmitter autoradiography techniques, we investigated this hypothesis by measuring specific [3H]idazoxan binding in 5 different areas of rat forebrain at 2 different stages of kindling development. After 2 class 1 kindled seizures, specific [3H]idazoxan binding was elevated significantly in the amygdala, but not in other forebrain regions. No differences in specific [3H]idazoxan binding were observed in any of the 5 brain regions in rats kindled to a single class 5 kindled motor seizure. Saturation of binding experiments indicated that the increase in amygdala [3H]idazoxan binding, following 2 class 1 kindled motor seizures, was due to an increase in the total number of alpha 2 receptor binding sites without a change in the affinity of the binding sites for [3H]idazoxan. Thus, the transient increase in alpha 2 receptors that occurs in the LC in the early stages of kindling also occurs in the forebrain region in which the kindled seizure originates.

  8. Regulation of β2-adrenergic receptor function by conformationally selective single-domain intrabodies

    DEFF Research Database (Denmark)

    Staus, Dean P; Wingler, Laura M; Strachan, Ryan T;

    2014-01-01

    to selectively bind agonist- or antagonist-occupied receptors. When expressed as intrabodies, they inhibited G protein activation (cyclic AMP accumulation), G protein-coupled receptor kinase (GRK)-mediated receptor phosphorylation, β-arrestin recruitment, and receptor internalization to varying extents...

  9. Effect of. cap alpha. -,. beta. -adrenergic receptor agonists and antagonists of the efflux of /sup 22/Na and uptake of /sup 42/K by rat brain cortical slices

    Energy Technology Data Exchange (ETDEWEB)

    Phillis, J.W.; Wu, P.H.; Thierry, D.L.

    1982-03-18

    The effects of norepinephrine on ion fluxes in rat brain cortical slices have now been ascertained. /sup 22/Na efflux and /sup 42/K influx are enhanced by norepinephrine. The increase in ion fluxes can be blocked by ouabain, phentolamine and propranolol, suggesting that the catecholamine activates a membrane sodium pump by a receptor-mediated step. The facilitation of /sup 22/Na efflux is stereospecific as demonstrated by the very weak action of D-norepinephrine at 10/sup -5/ M concentration. Various ..cap alpha..-adrenergic and ..beta..-adrenergic receptor agonists, including oxymetazoline, naphazoline, clonidine, tramazoline, methoxamine, phenylephrine, L-isoproterenol and methoxyphenamine are potent stimulants of the sodium pump as demonstrated by their enhancement of ion fluxes in rat brain cortical slices. The results are consistent with the hypothesis that norepinephrine hyperpolarizes central neurons by activating an ouabain-sensitive, receptor-mediated sodium pump.

  10. Differential regulation of atrial natriuretic peptide- and adrenergic receptor-dependent lipolytic pathways in human adipose tissue.

    Science.gov (United States)

    Moro, Cédric; Polak, Jan; Richterova, Blanka; Sengenès, Coralie; Pelikanova, Terezie; Galitzky, Jean; Stich, Vladimir; Lafontan, Max; Berlan, Michel

    2005-01-01

    The aim of the study was to investigate the regulation affecting the recently described atrial natriuretic peptide (ANP)-dependent lipolytic pathway in comparison with the adrenergic lipolytic cascade. We studied in vivo the effect of a euglycemic-hyperinsulinemic clamp on the changes occurring in the extracellular glycerol concentration (EGC) of subcutaneous adipose tissue (SCAT) during ANP or epinephrine perfusion in a microdialysis probe. Homologous desensitization and the incidence of hyperinsulinemia on the ANP- and catecholaminergic-dependent control of lipolysis were also investigated in vitro on fat cells from SCAT. When perfused in SCAT, epinephrine and ANP promoted an increase in EGC; the EGC increase was significantly lower during the clamp. The reduction of epinephrine-induced lipolysis was limited (18%) when phentolamine (an alpha(2)-adrenergic receptor [AR] antagonist) was perfused together with epinephrine. Unlike the effect of epinephrine, the response to ANP observed during the second perfusion was reduced by 32%. The increase in extracellular guanosine 3',5' -cyclic monophosphate concentration, which reflects ANP activity, was also reduced during the second perfusion. Desensitization of the lipolytic effects of ANP was observed in vitro after a 2-hour period of recovery, while the effects of alpha(2)-AR agonist or of epinephrine were unchanged. Insulin was without any effect on ANP-induced lipolysis and alpha(2)-AR-mediated antilipolysis, while it reduced beta-AR-induced lipolysis. The ANP-dependent lipolytic pathway undergoes desensitization in vitro and in situ. Insulin had no inhibitory effect on either ANP- or alpha(2)-AR-dependent pathways, while it counteracted the beta-AR pathway.

  11. Tumor necrosis factor expressed by primary hippocampal neurons and SH-SY5Y cells is regulated by alpha(2)-adrenergic receptor activation.

    Science.gov (United States)

    Renauld, A E; Spengler, R N

    2002-01-15

    Neuron expression of the cytokine tumor necrosis factor-alpha (TNF), and the regulation of the levels of TNF by alpha(2)-adrenergic receptor activation were investigated. Adult rat hippocampal neurons and phorbol ester (PMA)-differentiated SH-SY5Y cells were examined. Intracellular levels of TNF mRNA accumulation, as well as TNF protein and that released into the supernatant were quantified by in situ hybridization, immunocytochemistry and bioanalysis, respectively. Both neuron cultures demonstrated constitutive production of TNF. Activation of the alpha(2)-adrenergic receptor increased intracellular levels of TNF mRNA and protein in SH-SY5Y cells after addition of graded concentrations of the selective agonist, Brimonidine (UK-14304) to parallel cultures. Intracellular levels of mRNA were increased in a concentration-dependent fashion within 15 min of UK-14304 addition and were sustained during 24 hr of receptor activation. In addition, the levels of TNF in the supernatant were increased in both types of neuron cultures within 15 min of alpha(2)-adrenergic receptor activation. Furthermore, levels of TNF significantly increased in the supernatants of both neuron cultures after potassium-induced depolarization. A reduction in this depolarization-induced release occurred in hippocampal neuron cultures after exposure to the sympathomimetic tyramine with media replacement to deplete endogenous catecholamines. This finding reveals a role for endogenous catecholamines in the regulation of TNF production. Potassium-induced depolarization resulted in the release of TNF in hippocampal neuron cultures within 15 min but not until 24 hr in SH-SY5Y cultures demonstrating a temporally mediated event dependent upon cell type. Neuron expression of TNF, regulated by alpha(2)-adrenergic receptor activation demonstrates not only how a neuron controls its own production of this pleiotropic cytokine, but also displays a normal role for neurons in directing the many functions of TNF.

  12. The novel alpha 2-adrenoceptor agonist [3H]mivazerol binds to non-adrenergic binding sites in human striatum membranes that are distinct from imidazoline receptors.

    Science.gov (United States)

    Flamez, A; Gillard, M; De Backer, J P; Vauquelin, G; Noyer, M

    1997-07-01

    The alpha 2 adrenergic agonist [3H]mivazerol labelled two populations of binding sites in membranes from the human striatum. Forty per cent of the sites labelled by 3 nM [3H]mivazerol corresponded to alpha 2 adrenergic receptors as they displayed a high affinity for (-)-adrenaline and for rauwolscine. The remaining binding was displaced by mivazerol with a pIC50 of 6.5 +/- 0.1. These sites displayed higher affinity for dexmedetomidine (pIC50 = 7.1 +/- 0.1), but much lower affinity for clonidine (pIC50 < 5.0) and for idazoxan (pIC50 = 5.1 +/- 0.1). Mivazerol also showed low affinity for the [3H]clonidine-labelled I1 imidazoline receptors and for the [3H]idazoxan-labelled I2 receptors (pIC50 = 5.1 and 3.9, respectively). These results suggest that the non-adrenergic [3H]mivazerol binding sites are distinct from the imidazoline receptors in the human striatum.

  13. Effect of polymorphisms in the β2-adrenergic receptor on the susceptibility and pulmonary function of patients with chronic obstructive pulmonary disease: a meta analysis

    Institute of Scientific and Technical Information of China (English)

    NIU Li-ming; LIANG Ying; XU Ming; ZHANG You-yi; ZHANG Yuan; HE Bei

    2012-01-01

    Background Chronic obstructive pulmonary disease (COPD) is a heterogeneous and complex disease of which the pathogenesis remains largely unknown.Many factors could influence COPD development and progression.One of them is the genetic risk factor.A severe hereditary deficiency of alpha-1 antitrypsin is the best genetic proof.Four single nucleotide polymorphisms (SNPs) of beta2-adrenergic receptor (β2AR) result in single amino acid substitution.Two loci had been extensively studied and found that they could change the function of β2AR.Two SNPs consist of substitutions of glycine for arginine at amino acid position 16,glutamic acid for glutamine at position 27.Many studies proved that polymorphisms at position 16 and 27 altered the lung function of COPD patients or the patient's susceptibility to the development of COPD.However,there was no exclusive conclusion.Therefore,a meta analysis was done to investigate the effect of polymorphisms in the β2-adrenergic receptor (ADRB2) gene on the risk of COPD and lung function.Methods Comprehensive searches of MEDLINE,Embase,Ovid,HighWire,Cochrane Library,and Chinese databases (CBMdisc,VIP,CNKI,and Wanfang data) from January 1980 to September 2011 were performed,using the keywords:COPD OR chronic obstructive pulmonary disease AND adrenoreceptor OR adrenergic receptor AND polymorphism OR mutation OR variation.Case-control research or cross sectional studies in which diagnosis of COPD met the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines; all the studies reported the ADRB2 genotype at position 16 or 27.Outcomes measured were genotype frequency and forced expiratory volume in the first second (FEV1%) in both the case and control.Results Twelve case-control studies and eight cross-sectional studies were included.Compared to the control (n=1225),neither Gly/Gly (n=527) nor Arg/Arg (n=422) homozygotes at position 16 demonstrated increased susceptibility to COPD,with odds ratios (ORs) of 0.95 (95% Cl

  14. Conformational entropic maps of functional coupling domains in GPCR activation: A case study with beta2 adrenergic receptor

    Science.gov (United States)

    Liu, Fan; Abrol, Ravinder; Goddard, William, III; Dougherty, Dennis

    2014-03-01

    Entropic effect in GPCR activation is poorly understood. Based on the recent solved structures, researchers in the GPCR structural biology field have proposed several ``local activating switches'' that consisted of a few number of conserved residues, but have long ignored the collective dynamical effect (conformational entropy) of a domain comprised of an ensemble of residues. A new paradigm has been proposed recently that a GPCR can be viewed as a composition of several functional coupling domains, each of which undergoes order-to-disorder or disorder-to-order transitions upon activation. Here we identified and studied these functional coupling domains by comparing the local entropy changes of each residue between the inactive and active states of the β2 adrenergic receptor from computational simulation. We found that agonist and G-protein binding increases the heterogeneity of the entropy distribution in the receptor. This new activation paradigm and computational entropy analysis scheme provides novel ways to design functionally modified mutant and identify new allosteric sites for GPCRs. The authors thank NIH and Sanofi for funding this project.

  15. Defective Resensitization in Human Airway Smooth Muscle Cells Evokes β-Adrenergic Receptor Dysfunction in Severe Asthma.

    Directory of Open Access Journals (Sweden)

    Manveen K Gupta

    Full Text Available β2-adrenergic receptor (β2AR agonists (β2-agonist are the most commonly used therapy for acute relief in asthma, but chronic use of these bronchodilators paradoxically exacerbates airway hyper-responsiveness. Activation of βARs by β-agonist leads to desensitization (inactivation by phosphorylation through G-protein coupled receptor kinases (GRKs which mediate β-arrestin binding and βAR internalization. Resensitization occurs by dephosphorylation of the endosomal βARs which recycle back to the plasma membrane as agonist-ready receptors. To determine whether the loss in β-agonist response in asthma is due to altered βAR desensitization and/or resensitization, we used primary human airway smooth muscle cells (HASMCs isolated from the lungs of non-asthmatic and fatal-asthmatic subjects. Asthmatic HASMCs have diminished adenylyl cyclase activity and cAMP response to β-agonist as compared to non-asthmatic HASMCs. Confocal microscopy showed significant accumulation of phosphorylated β2ARs in asthmatic HASMCs. Systematic analysis of desensitization components including GRKs and β-arrestin showed no appreciable differences between asthmatic and non-asthmatic HASMCs. However, asthmatic HASMC showed significant increase in PI3Kγ activity and was associated with reduction in PP2A activity. Since reduction in PP2A activity could alter receptor resensitization, endosomal fractions were isolated to assess the agonist ready β2ARs as a measure of resensitization. Despite significant accumulation of β2ARs in the endosomes of asthmatic HASMCs, endosomal β2ARs cannot robustly activate adenylyl cyclase. Furthermore, endosomes from asthmatic HASMCs are associated with significant increase in PI3Kγ and reduced PP2A activity that inhibits β2AR resensitization. Our study shows that resensitization, a process considered to be a homeostasis maintaining passive process is inhibited in asthmatic HASMCs contributing to β2AR dysfunction which may underlie

  16. Hypocaloric diet reduces exercise-induced alpha 2-adrenergic antilipolytic effect and alpha 2-adrenergic receptor mRNA levels in adipose tissue of obese women.

    Science.gov (United States)

    Stich, V; Marion-Latard, F; Hejnova, J; Viguerie, N; Lefort, C; Suljkovicova, H; Langin, D; Lafontan, M; Berlan, M

    2002-03-01

    Previous investigations have shown that alpha 2-adrenoceptor (alpha 2-AR) stimulation blunts lipid mobilization during physiological activation of the sympathetic nervous system promoted by exercise in sc abdominal adipose tissue (SCAAT) in obese men. To investigate the effect of a low calorie diet (LCD) on the alpha 2-adrenergic responsiveness and on the expression of alpha 2-AR and beta 2-adrenoceptor (beta 2-AR) in SCAAT, 11 obese women (weight: 99.1 +/- 4.6 kg; body mass index: 34.3 +/- 1.1 kg/m(2)) received a 12-wk diet providing 500 kcal/d less than their usual diet. The exercise-induced alpha 2-adrenergic antilipolytic effect was investigated in SCAAT before and at the end of LCD. Changes in extracellular glycerol concentration and local blood flow were measured in SCAAT during a 45-min exercise bout (50% of heart rate reserve) using a control microdialysis probe and a probe supplemented with the alpha2-AR antagonist phentolamine. SCAAT biopsies were performed for determination of mRNA levels using RT-competitive PCR. Plasma catecholamine responses to exercise bout were not different before and at the end of LCD. Before LCD, the exercise-induced increase in extracellular glycerol concentration was potentiated by phentolamine supplementation, while this potentiating effect of the alpha-antagonist was not observed at the end of LCD. No changes were observed for beta 2-AR and hormone-sensitive lipase mRNA levels, while alpha 2-AR mRNA level was significantly decreased in adipose tissue during LCD. These findings show that alpha 2-AR-mediated antilipolytic action is reduced by a moderate hypocaloric diet and that down-regulation of alpha 2-AR mRNA levels may participate in the decrease of the alpha 2-adrenergic effect revealed by microdialysis.

  17. Higenamine 4'-O-β-d-glucoside in the lotus plumule induces glucose uptake of L6 cells through β2-adrenergic receptor.

    Science.gov (United States)

    Kato, Eisuke; Inagaki, Yosuke; Kawabata, Jun

    2015-07-01

    Hypoglycemic effect is an efficient means to modulate elevated blood glucose levels in patients with diabetes. We found that the extract of lotus plumule (the germ of Nelumbo nucifera Gaertn. seed) showed potent glucose uptake enhancement activity against L6 myotubes, which results in a hypoglycemic effect. This activity was further investigated, and an active constituent was identified as a single bioactive compound, higenamine 4'-O-β-d-glucoside. Mechanistic studies employing phosphatidylinositol 3-kinase (PI3K) inhibitor, AMP-activated protein kinase (AMPK) inhibitor, or adrenergic receptor antagonist showed that the compound induced its activity through β2-adrenergic receptor. Patients with type II diabetes mellitus frequently develop insulin resistance. Owing to the differences between the mechanism of action of insulin and of the isolated compound, the compound or lotus plumule itself may have the possibility of modulating blood glucose levels in insulin-resistant patients effectively.

  18. A randomised trial of a pre-synaptic stimulator of DA2-dopaminergic and alpha2-adrenergic receptors on morbidity and mortality in patients with heart failure

    DEFF Research Database (Denmark)

    Torp-Pedersen, Christian; Køber, Lars; Carlsen, Jan E;

    2008-01-01

    Background: By pre-synaptic stimulation of DA(2)-dopaminergic and alpha(2)-adrenergic receptors, nolomirole inhibits norepinephrine secretion from sympathetic nerve endings. We performed a clinical study with nolomirole in patients with heart failure (HF). Methods: The study was designed as a mul......Background: By pre-synaptic stimulation of DA(2)-dopaminergic and alpha(2)-adrenergic receptors, nolomirole inhibits norepinephrine secretion from sympathetic nerve endings. We performed a clinical study with nolomirole in patients with heart failure (HF). Methods: The study was designed...... as a multicentre, double blind, parallel group trial of 5 mg b.i.d. of nolomirole (n=501) versus placebo (n=499) in patients with severe left ventricular systolic dysfunction, recently in New York Heart Association (NYHA) class III/IV. The primary endpoint was time to all cause death or hospitalisation for HF...

  19. Role of descending noradrenergic system and spinal α2-adrenergic receptors in the effects of gabapentin on thermal and mechanical nociception after partial nerve injury in the mouse

    OpenAIRE

    Tanabe, Mitsuo; Takasu, Keiko; Kasuya, Noriyo; Shimizu, Shinobu; Honda, Motoko; Ono, Hideki

    2005-01-01

    To gain further insight into the mechanisms underlying the antihyperalgesic and antiallodynic actions of gabapentin, a chronic pain model was prepared by partially ligating the sciatic nerve in mice. The mice then received systemic or local injections of gabapentin combined with either central noradrenaline (NA) depletion by 6-hydroxydopamine (6-OHDA) or α-adrenergic receptor blockade.Intraperitoneally (i.p.) administered gabapentin produced antihyperalgesic and antiallodynic effects that wer...

  20. Role of descending noradrenergic system and spinal alpha2-adrenergic receptors in the effects of gabapentin on thermal and mechanical nociception after partial nerve injury in the mouse.

    Science.gov (United States)

    Tanabe, Mitsuo; Takasu, Keiko; Kasuya, Noriyo; Shimizu, Shinobu; Honda, Motoko; Ono, Hideki

    2005-03-01

    1. To gain further insight into the mechanisms underlying the antihyperalgesic and antiallodynic actions of gabapentin, a chronic pain model was prepared by partially ligating the sciatic nerve in mice. The mice then received systemic or local injections of gabapentin combined with either central noradrenaline (NA) depletion by 6-hydroxydopamine (6-OHDA) or alpha-adrenergic receptor blockade. 2. Intraperitoneally (i.p.) administered gabapentin produced antihyperalgesic and antiallodynic effects that were manifested by elevation of the withdrawal threshold to a thermal (plantar test) or mechanical (von Frey test) stimulus, respectively. 3. Similar effects were obtained in both the plantar and von Frey tests when gabapentin was injected intracerebroventricularly (i.c.v.) or intrathecally (i.t.), suggesting that it acts at both supraspinal and spinal loci. This novel supraspinal analgesic action of gabapentin was only obtained in ligated neuropathic mice, and gabapentin (i.p. and i.c.v.) did not affect acute thermal and mechanical nociception. 4. In mice in which central NA levels were depleted by 6-OHDA, the antihyperalgesic and antiallodynic effects of i.p. and i.c.v. gabapentin were strongly suppressed. 5. The antihyperalgesic and antiallodynic effects of systemic gabapentin were reduced by both systemic and i.t. administration of yohimbine, an alpha2-adrenergic receptor antagonist. By contrast, prazosin (i.p. or i.t.), an alpha1-adrenergic receptor antagonist, did not alter the effects of gabapentin. 6. It was concluded that the antihyperalgesic and antiallodynic effects of gabapentin are mediated substantially by the descending noradrenergic system, resulting in the activation of spinal alpha2-adrenergic receptors.

  1. Phosphorylation of Cav1.2 on S1928 uncouples the L-type Ca2+ channel from the β2 adrenergic receptor.

    Science.gov (United States)

    Patriarchi, Tommaso; Qian, Hai; Di Biase, Valentina; Malik, Zulfiquar A; Chowdhury, Dhrubajyoti; Price, Jennifer L; Hammes, Erik A; Buonarati, Olivia R; Westenbroek, Ruth E; Catterall, William A; Hofmann, Franz; Xiang, Yang K; Murphy, Geoffrey G; Chen, Chao-Ye; Navedo, Manuel F; Hell, Johannes W

    2016-06-15

    Agonist-triggered downregulation of β-adrenergic receptors (ARs) constitutes vital negative feedback to prevent cellular overexcitation. Here, we report a novel downregulation of β2AR signaling highly specific for Cav1.2. We find that β2-AR binding to Cav1.2 residues 1923-1942 is required for β-adrenergic regulation of Cav1.2. Despite the prominence of PKA-mediated phosphorylation of Cav1.2 S1928 within the newly identified β2AR binding site, its physiological function has so far escaped identification. We show that phosphorylation of S1928 displaces the β2AR from Cav1.2 upon β-adrenergic stimulation rendering Cav1.2 refractory for several minutes from further β-adrenergic stimulation. This effect is lost in S1928A knock-in mice. Although AMPARs are clustered at postsynaptic sites like Cav1.2, β2AR association with and regulation of AMPARs do not show such dissociation. Accordingly, displacement of the β2AR from Cav1.2 is a uniquely specific desensitization mechanism of Cav1.2 regulation by highly localized β2AR/cAMP/PKA/S1928 signaling. The physiological implications of this mechanism are underscored by our finding that LTP induced by prolonged theta tetanus (PTT-LTP) depends on Cav1.2 and its regulation by channel-associated β2AR.

  2. Beta 2-adrenergic receptor activation enhances neurogenesis in Alzheimer’s disease mice

    Institute of Scientific and Technical Information of China (English)

    Gao-shang Chai; Yang-yang Wang; Amina Yasheng; Peng Zhao

    2016-01-01

    Impaired hippocampal neurogenesis is one of the early pathological features of Alzheimer’s disease. Enhancing adult hippocampal neuro-genesis has been pursued as a potential therapeutic strategy for Alzheimer’s disease. Recent studies have demonstrated that environmental novelty activates β2-adrenergic signaling and prevents the memory impairment induced by amyloid-β oligomers. Here, we hypothesized that β2-adrenoceptor activation would enhance neurogenesis and ameliorate memory deifcits in Alzheimer’s disease. To test this hypothe-sis, we investigated the effects and mechanisms of action of β2-adrenoceptor activation on neurogenesis and memory in amyloid precursor protein/presenilin 1 (APP/PS1) mice using the agonist clenbuterol (intraperitoneal injection, 2 mg/kg). We found that β2-adrenoceptor ac-tivation enhanced hippocampal neurogenesis, ameliorated memory deifcits, and increased dendritic branching and the density of dendritic spines. hTese effects were associated with the upregulation of postsynaptic density 95, synapsin 1 and synaptophysin in APP/PS1 mice. Furthermore, β2-adrenoceptor activation decreased cerebral amyloid plaques by decreasing APP phosphorylation at hTr668. hTese ifndings suggest that β2-adrenoceptor activation enhances neurogenesis and ameliorates memory deifcits in APP/PS1 mice.

  3. Effect of Increased Cyclic AMP Concentration on Muscle Protein Synthesis and Beta-Adrenergic Receptor Expression in Chicken Skeletal Muscle Cells in Culture

    Science.gov (United States)

    Young, R. B.; Vaughn, J. R.; Bridge, K. Y.; Smith, C. K.

    1998-01-01

    Analogies of epinephrine are known to cause hypertrophy of skeletal muscle when fed to animals. These compounds presumably exert their physiological action through interaction with the P-adrenergic receptor. Since the intracellular signal generated by the Beta-adrenergic receptor is cyclic AMP (cAMP), experiments were initiated in cell culture to determine if artificial elevation of cAMP by treatment with forskolin would alter muscle protein metabolism and P-adrenergic receptor expression. Chicken skeletal muscle cells after 7 days in culture were treated with 0.2-30 micrometers forskolin for a total of three days. At the end of the treatment period, both the concentration of cAMP and the quantity of myosin heavy chain (MHC) were measured. Concentration of cAMP in forskolin-treated cells increased up to 10-fold in a dose dependent manner. In contrast, the quantity of MHC was increased approximately 50% above control cells at 0.2 micrometers forskolin, but exhibited a gradual decline at higher levels of forskolin so that the quantity of MHC in cells treated with 30 micrometers forskolin was not significantly different from controls. Curiously, the intracellular concentration of cAMP which elicited the maximum increase in the quantity of MHC was only 40% higher than cAMP concentration in control cells.

  4. α1A-adrenergic receptor induces activation of extracellular signal-regulated kinase 1/2 through endocytic pathway.

    Directory of Open Access Journals (Sweden)

    Fei Liu

    Full Text Available G protein-coupled receptors (GPCRs activate mitogen-activated protein kinases through a number of distinct pathways in cells. Increasing evidence has suggested that endosomal signaling has an important role in receptor signal transduction. Here we investigated the involvement of endocytosis in α(1A-adrenergic receptor (α(1A-AR-induced activation of extracellular signal-regulated kinase 1/2 (ERK1/2. Agonist-mediated endocytic traffic of α(1A-AR was assessed by real-time imaging of living, stably transfected human embryonic kidney 293A cells (HEK-293A. α(1A-AR was internalized dynamically in cells with agonist stimulation, and actin filaments regulated the initial trafficking of α(1A-AR. α(1A-AR-induced activation of ERK1/2 but not p38 MAPK was sensitive to disruption of endocytosis, as demonstrated by 4°C chilling, dynamin mutation and treatment with cytochalasin D (actin depolymerizing agent. Activation of protein kinase C (PKC and C-Raf by α(1A-AR was not affected by 4°C chilling or cytochalasin D treatment. U73122 (a phospholipase C [PLC] inhibitor and Ro 31-8220 (a PKC inhibitor inhibited α(1B-AR- but not α(1A-AR-induced ERK1/2 activation. These data suggest that the endocytic pathway is involved in α(1A-AR-induced ERK1/2 activation, which is independent of G(q/PLC/PKC signaling.

  5. Agonist-promoted desensitization and phosphorylation of. cap alpha. /sub 1/-adrenergic receptors coupled to stimulation of phosphatidylinositol metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Leeb-Lundberg, L.M.F.; Cotecchia, S.; Caron, M.G.; Lefkowitz, R.J.

    1986-03-05

    In the DDT/sub 1/ MF-2 hamster vas deferens smooth muscle cell line the ..cap alpha../sub 1/-adrenergic receptor (..cap alpha../sub 1/-AR) agonist norepinephrine (NE) promotes rapid attenuation of ..cap alpha../sub 1/-AR-mediated phosphatidylinositol (PI) metabolism which is paralleled by rapid phosphorylation of the ..cap alpha../sub 1/-AR. Cells were labeled by incubation with /sup 32/P/sub i/. Coincubation with NE (100 ..mu..M) significantly increases the rate of /sup 32/P-labeling of both PI and phosphatidic acid. Pretreatment of cells with 100 ..mu..M NE (in the presence of 1 ..mu..M propranolol to prevent ..beta..-AR interactions) results in a drastic attenuation of the NE response on PI metabolism. ..cap alpha../sub 1/-AR from labeled cells can be solubilized and purified by affinity chromatography on Affigel-A55414 and wheat germ agglutinin agarose chromatography. SDS-PAGE of purified ..cap alpha../sub 1/-AR shows a NE-promoted increase in phosphorylation of the M/sub r/ 80K ligand binding peptide. Stoichiometry of phosphorylation increases from approx. 1 mol phosphate/mol ..cap alpha../sub 1/-AR in the basal condition to approx. 2.5 after NE treatment. Both desensitization and phosphorylation are rapid being maximal within 10-20 min of agonist exposure. These results together with previous findings that phorbol esters promote rapid ..cap alpha../sub 1/-AR uncoupling and phosphorylation suggest that receptor phosphorylation is an important mechanism of regulation of ..cap alpha../sub 1/-AR receptor responsiveness.

  6. Adrenergic β2-receptors mediates visceral hypersensitivity induced by heterotypic intermittent stress in rats.

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    Chunhua Zhang

    Full Text Available Chronic visceral pain in patients with irritable bowel syndrome (IBS has been difficult to treat effectively partially because its pathophysiology is not fully understood. Recent studies show that norepinephrine (NE plays an important role in the development of visceral hypersensitivity. In this study, we designed to investigate the role of adrenergic signaling in visceral hypersensitivity induced by heterotypical intermittent stress (HIS. Abdominal withdrawal reflex scores (AWRs used as visceral sensitivity were determined by measuring the visceromoter responses to colorectal distension. Colon-specific dorsal root ganglia neurons (DRGs were labeled by injection of DiI into the colon wall and were acutely dissociated for whole-cell patch-clamp recordings. Blood plasma level of NE was measured using radioimmunoassay kits. The expression of β2-adrenoceptors was measured by western blotting. We showed that HIS-induced visceral hypersensitivity was attenuated by systemic administration of a β-adrenoceptor antagonist propranolol, in a dose-dependent manner, but not by a α-adrenoceptor antagonist phentolamine. Using specific β-adrenoceptor antagonists, HIS-induced visceral hypersensitivity was alleviated by β2 adrenoceptor antagonist but not by β1- or β3-adrenoceptor antagonist. Administration of a selective β2-adrenoceptor antagonist also normalized hyperexcitability of colon-innervating DRG neurons of HIS rats. Furthermore, administration of β-adrenoceptor antagonist suppressed sustained potassium current density (IK without any alteration of fast-inactivating potassium current density (IA. Conversely, administration of NE enhanced the neuronal excitability and produced visceral hypersensitivity in healthy control rats, and blocked by β2-adrenoceptor antagonists. In addition, HIS significantly enhanced the NE concentration in the blood plasma but did not change the expression of β2-adrenoceptor in DRGs and the muscularis externa of the

  7. Reversible adrenergic alpha-receptor blocking action of 2,4'-dimethyl-3-piperidino-propiophenone (tolperisone).

    Science.gov (United States)

    Furuta, Y; Yoshikawa, A

    1976-10-01

    The vascular action of 2,4'-dimethyl-3-piperidino-propiophenone hydrochloride (tolperisone hydrochloride), a centrally acting muscle relaxant, was investigated in pentobarbital anesthetized dogs. Tolperisone given intravenously produced a transient hypotension, tachycardia, and hyperventilation. The drug increased the femoral arterial flow, and decreased the superior mesenteric arterial flow following an initial transient increase. When injected directly into femoral and mesenteric arteries, tolperisone caused a rapid increase in both arterial flow (vasodilatation). However, femoral vessels were about 90 times as sensitive as mesenteric vessels to tolperisone. These results indicate that tolperisone shifts the blood volume from mesenteric (visceral) vessels to femoral (skeltal) ones. The femoral vasodilatation produced by i.a. tolperisone was not depressed by the pretreatment with i.a. propranolol, atropine or chlorphenylamine. Tolperisone decreased the contractile force in an isolated and cross-circulated papillary muscle. Tolperisone produced adrenaline reversal and antagonized the pressor response to noradrenaline. Moreover, femoral vasoconstriction caused by i.a. adrenaline was converted to vasodilatation and that caused by i.a. noradrenaline was depressed during an i.a. infusion of tolperisone. These results indicate that tolperisone blocks adrenergic alpha-receptors. The blocking action was rapid in onset, short-lived, and in addition, competitive.

  8. Acupuncture Attenuates Renal Sympathetic Activity and Blood Pressure via Beta-Adrenergic Receptors in Spontaneously Hypertensive Rats

    Science.gov (United States)

    Ye, Yang; Wang, Xue-Rui; Li, Fang; Xiao, Ling-Yong; Shi, Guang-Xia

    2017-01-01

    The sympathetic nervous system, via epinephrine and norepinephrine, regulates β-adrenergic receptor (β-AR) expression, and renal sympathetic activation causes sustained increases in blood pressure by enhanced renin release. In this study, we aim to investigate the effect and underlying mechanism of acupuncture at Taichong (LR3) on renal sympathetic activity in spontaneously hypertensive rats. Unanesthetized rats were subject to daily acupuncture for 2 weeks. Mean blood pressure (MBP) and heart rate variability (HRV) were monitored at days 0, 7, and 14 by radiotelemetry. After euthanasia on the 14th day, blood and the kidneys were collected and subject to the following analyses. Epinephrine and norepinephrine were detected by ELISA. The expression of β-ARs was studied by western blotting and PCR. The renin content was analyzed by radioimmunoassay. 14-day acupuncture significantly attenuates the increase of MBP. The HRV indices, the standard deviation of all normal NN intervals (SDNN), and the ratio of the low-frequency component to the high-frequency component (LF/HF) were improved following acupuncture. Renal sympathetic activation induced upregulation of epinephrine, norepinephrine, and renin content were attenuated by acupuncture. In addition, acupuncture decreased β1-AR expression and improved β2-AR expression. These results indicated that acupuncture relieves the increased MBP via the regulation of renal sympathetic activity and β-ARs. PMID:28270938

  9. Experimental study on alteration of adrenergic receptors activity in neuronal membranes protein of cerebral cortex following brain trauma in rats

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-wei; XU Ru-xiang; QI Yi-long; CHEN Chang-cai

    2001-01-01

    Objective: To define the course of changes taken by α1 and β adrenergic receptors (AR) activity after traumatic brain injury (TBI) and explore the approach for secondary brain injury (SBI) management. Methods: The neuronal membrane protein of cortex were extracted from the rats subject to traumatic brain injury, and the changes of α1- and β-AR activities in the neuronal membranes were examined by radio ligand binding assay (RLBA). Results: α1- and β-AR activities underwent obvious changes, reaching their peak values at 24 h after TBI. α1-AR binding density (Bmax) reduced by 22.6%while the ligand affinity increased by 66.7%, and for β-AR, however, Bmax increased by 116.9% and the ligand affinity reduced by 50.7%. Their antagonists could counteract the changes ofα1- and β-AR activity. Conclusion: The patterns of changes varies between α1- and β-AR activity after TBI, suggesting their different roles in the neuronal membranes after brain trauma, and timely administration of AR antagonists is potentially beneficial in TBI management.

  10. Activation of Cyclic AMP Synthesis by Full and Partial Beta-Adrenergic Receptor Agonists in Chicken Skeletal Muscle Cells

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.

    2003-01-01

    Several beta-adrenergic receptor (bAR) agonists are known to cause hypertrophy of skeletal muscle tissue. Accordingly, five bAR agonists encompassing a range in activity from strong to weak were evaluated for their ability to stimulate CAMP accumulation in embryonic chicken skeletal muscle cells in culture. Two strong agonists (epinephrine and isoproterenol), one moderate agonist (albuterol), and two weak agonists known to cause hypertrophy in animals (clenbuterol and cimaterol) were studied. Dose response curves were determined over six orders of magnitude in concentration for each agonist, and values were determined for their maximum stimulation of CAMP synthesis rate (Bmax) and the agonist concentration at which 50% stimulation of CAMP synthesis (EC50) occurred. Bmax values decreased in the following order: isoproterenol, epinephrine, albuterol, cimaterol, clenbuterol. Cimaterol and clenbuterol at their Bmax concentrations were approximately 15-fold weaker than isoproterenol in stimulating the rate of CAMP synthesis. When cimaterol and clenbuterol were added to culture media at concentrations known to cause significant muscle hypertrophy in animals, there was no detectable effect on stimulation of CAMP synthesis. Finally, these same levels of cimaterol and clenbuterol did not antagonize the stimulation of CAMP by either epinephrine or isoproterenol.

  11. Nebivolol protects against myocardial infarction injury via stimulation of beta 3-adrenergic receptors and nitric oxide signaling.

    Directory of Open Access Journals (Sweden)

    Zheng Zhang

    Full Text Available Nebivolol, third-generation β-blocker, may activate β3-adrenergic receptor (AR, which has been emerged as a novel and potential therapeutic targets for cardiovascular diseases. However, it is not known whether nebivolol administration plays a cardioprotective effect against myocardial infarction (MI injury. Therefore, the present study was designed to clarify the effects of nebivolol on MI injury and to elucidate the underlying mechanism. MI model was constructed by left anterior descending (LAD artery ligation. Nebivolol, β3-AR antagonist (SR59230A, Nitro-L-arginine methylester (L-NAME or vehicle was administered for 4 weeks after MI operation. Cardiac function was monitored by echocardiography. Moreover, the fibrosis and the apoptosis of myocardium were assessed by Masson's trichrome stain and TUNEL assay respectively 4 weeks after MI. Nebivolol administration reduced scar area by 68% compared with MI group (p<0.05. Meanwhile, nebivolol also decreased the myocardial apoptosis and improved the heart function after MI (p<0.05 vs. MI. These effects were associated with increased β3-AR expression. Moreover, nebivolol treatment significantly increased the phosphorylation of endothelial NOS (eNOS and the expression of neuronal NOS (nNOS. Conversely, the cardiac protective effects of nebivolol were abolished by SR and L-NAME. These results indicate that nebivolol protects against MI injury. Furthermore, the cardioprotective effects of nebivolol may be mediated by β3-AR-eNOS/nNOS pathway.

  12. Regulation of gap-junction protein connexin 43 by β-adrenergic receptor stimulation in rat cardiomyocytes

    Institute of Scientific and Technical Information of China (English)

    Yi XIA; Kai-zheng GONG; Ming XU; You-yi ZHANG; Ji-hong GUO; Yao SONG; Ping ZHANG

    2009-01-01

    Aim:β-adrenergic receptor (β-AR) agonists are among the most potent factors regulating cardiac electrophysiological properties.Connexin 43 (Cx43),the predominant gap-junction protein in the heart,has an indispensable role in modulating cardiac electric activities by affecting gap-junction function.The present study investigates the effects of short-term stimulation of β-AR subtypes on Cx43 expression and gap junction intercellular communication (GJIC) function.Methods:The level of Cx43 expression in neonatal rat cardiomyocytes (NRCM) was detected by a Western blotting assay.The GJIC function was evaluated by scrape loading/dye transfer assay.Results:Stimulation of β-AR by the agonist isoproterenol for 5 min induces the up-regulation of nonphosphorylated Cx43 protein level,but not total Cx43.Selective β2-AR inhibitor ICI 118551,but not β-AR inhibitor CGP20712,could fully abolish the effect.Moreover,pretreatment with both protein kinase A inhibitor H89 and G,protein inhibitor pertussis toxin also inhibited the isoproterenol-induced increase of nonphosphorylated Cx43 expression.Isoproterenol-induced up-regulation of nonphosphorylated Cx43 is accompanied with enhanced GJIC function.Conclusion:Taken together,β2-AR stimulation increases the expression of nonphosphorylated Cx43,thereby enhancing the gating function of gap junctions in cardiac myocytes in both a protein kinase A-and G1-dependent manner.

  13. Molecular mechanisms underlying β-adrenergic receptor-mediated cross-talk between sympathetic neurons and immune cells.

    Science.gov (United States)

    Lorton, Dianne; Bellinger, Denise L

    2015-03-11

    Cross-talk between the sympathetic nervous system (SNS) and immune system is vital for health and well-being. Infection, tissue injury and inflammation raise firing rates of sympathetic nerves, increasing their release of norepinephrine (NE) in lymphoid organs and tissues. NE stimulation of β2-adrenergic receptors (ARs) in immune cells activates the cAMP-protein kinase A (PKA) intracellular signaling pathway, a pathway that interfaces with other signaling pathways that regulate proliferation, differentiation, maturation and effector functions in immune cells. Immune-SNS cross-talk is required to maintain homeostasis under normal conditions, to develop an immune response of appropriate magnitude after injury or immune challenge, and subsequently restore homeostasis. Typically, β2-AR-induced cAMP is immunosuppressive. However, many studies report actions of β2-AR stimulation in immune cells that are inconsistent with typical cAMP-PKA signal transduction. Research during the last decade in non-immune organs, has unveiled novel alternative signaling mechanisms induced by β2-AR activation, such as a signaling switch from cAMP-PKA to mitogen-activated protein kinase (MAPK) pathways. If alternative signaling occurs in immune cells, it may explain inconsistent findings of sympathetic regulation of immune function. Here, we review β2-AR signaling, assess the available evidence for alternative signaling in immune cells, and provide insight into the circumstances necessary for "signal switching" in immune cells.

  14. Sympathetic nervous system promotes hepatocarcinogenesis by modulating inflammation through activation of alpha1-adrenergic receptors of Kupffer cells.

    Science.gov (United States)

    Huan, Hong-Bo; Wen, Xu-Dong; Chen, Xue-Jiao; Wu, Lin; Wu, Li-Li; Zhang, Liang; Yang, Da-Peng; Zhang, Xia; Bie, Ping; Qian, Cheng; Xia, Feng

    2017-01-01

    The sympathetic nervous system (SNS) is known to play a significant role in tumor initiation and metastasis. Hepatocellular carcinoma (HCC) frequently occurs in cirrhotic livers after chronic inflammation, and the SNS is hyperactive in advanced liver cirrhosis. However, it remains unclear whether the SNS promotes hepatocarcinogenesis by modulating chronic liver inflammation. In this study, a retrospective pathological analysis and quantification of sympathetic nerve fiber densities (tyrosine hydroxylase, TH(+)) in HCC patients, and diethylnitrosamine (DEN)-induced hepatocarcinogenesis in rats were performed. Our data showed that high density of sympathetic nerve fibers and α1-adrenergic receptors (ARs) of Kupffer cells (KCs) were associated with a poor prognosis of HCC. Sympathetic denervation or blocking of α1-ARs decreased DEN-induced HCC incidence and tumor development. In addition, synergistic effects of interleukin-6 (IL-6) and transforming growth factor-beta (TGF-β) in hepatocarcinogenesis were observed. The suppression of the SNS reduced IL-6 and TGF-β expression, which suppressed hepatocarcinogenesis, and KCs play a key role in this process. After the ablation of KCs, IL-6 and TGF-β expression and the development of HCC were inhibited. This study demonstrates that sympathetic innervation is crucial for hepatocarcinogenesis and that the SNS promotes hepatocarcinogenesis by activating α1-ARs of KCs to boost the activation of KCs and to maintain the inflammatory microenvironment. These results indicate that sympathetic denervation or α1-ARs blockage may represent novel treatment approaches for HCC.

  15. Management of facial erythema of rosacea: what is the role of topical α-adrenergic receptor agonist therapy?

    Science.gov (United States)

    Del Rosso, James Q

    2013-12-01

    Several more recent advances have led to a better understanding of the pathophysiologic mechanisms involved in rosacea and therapeutic modalities used for treatment. Although the clinical features may vary among patients, there are some unifying mechanisms that appear to relate to the more common presentations of rosacea. Both neurovascular dysregulation and augmented immune detection and response appear to play central roles that lead to many of the signs and symptoms of rosacea. Diffuse central facial erythema is a very common finding that intensifies during flares and persists to varying degrees between flares. This background of facial redness occurs secondary to vasodilation and fixed vascular changes that develop over time. Physical modalities are commonly used to treat the erythema that persists as a result of fixed changes in superficial cutaneous vasculature that do not remit after treatment with agents whose mechanisms are active primarily against some of the inflammatory processes operative in rosacea (ie metronidazole, azelaic acid, tetracyclines). As enlarged superficial cutaneous vessels that contribute to the fixed background facial redness of rosacea remain vasoactive to sympathetic nervous system innervation, topical α-adrenergic receptor agonists, namely brimonidine and oxymetazoline, are currently under evaluation for the treatment of facial erythema of rosacea. This article focuses on the clinical differentiation of facial erythema of rosacea and its management.

  16. Site-specific O-glycosylation by Polypeptide GalNAc-transferase T2 Co-regulates Beta1-adrenergic Receptor N-terminal Cleavage.

    Science.gov (United States)

    Goth, Christoffer K; Tuhkanen, Hanna E; Khan, Hamayun; Lackman, Jarkko J; Wang, Shengjun; Narimatsu, Yoshiki; Holst Hansen, Lasse; Overall, Christopher; Clausen, Henrik; Schjoldager, Katrine T; Petäjä-Repo, Ulla E

    2017-02-06

    The β1-adrenergic receptor (β1AR) is a G protein-coupled receptor (GPCR) and the predominant adrenergic receptor subtype in the heart, where it mediates cardiac contractility and the force of contraction. Although it is the most important target for β-adrenergic antagonists, such as beta-blockers, relatively little is still known about its regulation. We have previously shown that β1AR undergoes constitutive and regulated N-terminal cleavage participating in receptor down-regulation, and moreover that the receptor is modified by O-glycosylation. Here we demonstrate that the polypeptide GalNAc-transferase 2 (GalNAc-T2) specifically O-glycosylates β1AR at five residues in the extracellular N-terminus, including the Ser49 residue at a location of the common Ser49Gly single-nucleotide polymorphism. Using in vitro O-glycosylation and proteolytic cleavage assays, a cell line deficient in O-glycosylation, GalNAc-T edited cell line model systems, and a GalNAc-T2 knockout rat model, we show that GalNAc-T2 co-regulates the metalloproteinase-mediated limited proteolysis of β1AR. Furthermore, we demonstrate that impaired O-glycosylation and enhanced proteolysis leads to attenuated receptor signaling, as the maximal response elicited by the βAR agonist isoproterenol and it potency in a cAMP accumulation assay was decreased in HEK293 cells lacking GalNAc-T2. Our findings reveal, for the first time, a GPCR as a target for co-regulatory functions of site-specific O-glycosylation mediated by a unique GalNAc-T isoform. The results provide a new level of β1AR regulation that may open up possibilities for new therapeutic strategies for cardiovascular diseases.

  17. Adrenergic deficiency leads to impaired electrical conduction and increased arrhythmic potential in the embryonic mouse heart.

    Science.gov (United States)

    Baker, Candice; Taylor, David G; Osuala, Kingsley; Natarajan, Anupama; Molnar, Peter J; Hickman, James; Alam, Sabikha; Moscato, Brittany; Weinshenker, David; Ebert, Steven N

    2012-07-01

    To determine if adrenergic hormones play a critical role in the functional development of the cardiac pacemaking and conduction system, we employed a mouse model where adrenergic hormone production was blocked due to targeted disruption of the dopamine β-hydroxylase (Dbh) gene. Immunofluorescent histochemical evaluation of the major gap junction protein, connexin 43, revealed that its expression was substantially decreased in adrenergic-deficient (Dbh-/-) relative to adrenergic-competent (Dbh+/+ and Dbh+/-) mouse hearts at embryonic day 10.5 (E10.5), whereas pacemaker and structural protein staining appeared similar. To evaluate cardiac electrical conduction in these hearts, we cultured them on microelectrode arrays (8×8, 200 μm apart). Our results show a significant slowing of atrioventricular conduction in adrenergic-deficient hearts compared to controls (31.4±6.4 vs. 15.4±1.7 ms, respectively, pheart rate and rhythm, mouse hearts from adrenergic-competent and deficient embryos were cultured ex vivo at E10.5, and heart rates were measured before and after challenge with the β-adrenergic receptor agonist, isoproterenol (0.5 μM). On average, all hearts showed increased heart rate responses following isoproterenol challenge, but a significant (phearts. These results show that adrenergic hormones may influence heart development by stimulating connexin 43 expression, facilitating atrioventricular conduction, and helping to maintain cardiac rhythm during a critical phase of embryonic development.

  18. Alpha adrenergic receptors in renal pelvis and calyces: can rat models be used?

    Directory of Open Access Journals (Sweden)

    Osman Raif Karabacakb

    2014-10-01

    Full Text Available We aimed, in this study, to determine the distribution of α-1 AR subtypes in rat and human pelvis and calyces, and to evaluate, by comparing these two species, the possibility of rats to be used as models for humans. Twenty patients with renal carcinoma were included into the study. The patients underwent radical nephrectomy for renal cell carcinoma (RCC. After nephrectomy, specimens were evaluated and excisional biopsies from healthy pelvis and calyces tissues were performed. When pathology confirmed the non-invasion of RCC, specimen was included into the study. A total of 7 adult Wistar Albino (250-300 g female rats were used in this study. Specimens included renal pelvis and calyces. All specimens were evaluated under light microscope histopathologically. The concentrations of the receptor densities did not differ between the two groups. With the demonstration of the α receptors in rat kidneys and calyces, many receptor-based studies concerning both humans and rats can take place. Novel medication targeting these subtypes -in this matter α1A and α1D for renal pelvis and calyces- may be helpful for expulsive therapy and/or pain relief. With the demonstration of similar receptor densities between human and rat tissues, rat model may be useful for α-receptor trials for renal pelvis and calyces.

  19. Temporal Dissection of Rate Limiting Transcriptional Events Using Pol II ChIP and RNA Analysis of Adrenergic Stress Gene Activation.

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    Daniel P Morris

    Full Text Available In mammals, increasing evidence supports mechanisms of co-transcriptional gene regulation and the generality of genetic control subsequent to RNA polymerase II (Pol II recruitment. In this report, we use Pol II Chromatin Immunoprecipitation to investigate relationships between the mechanistic events controlling immediate early gene (IEG activation following stimulation of the α1a-Adrenergic Receptor expressed in rat-1 fibroblasts. We validate our Pol II ChIP assay by comparison to major transcriptional events assessable by microarray and PCR analysis of precursor and mature mRNA. Temporal analysis of Pol II density suggests that reduced proximal pausing often enhances gene expression and was essential for Nr4a3 expression. Nevertheless, for Nr4a3 and several other genes, proximal pausing delayed the time required for initiation of productive elongation, consistent with a role in ensuring transcriptional fidelity. Arrival of Pol II at the 3' cleavage site usually correlated with increased polyadenylated mRNA; however, for Nfil3 and probably Gprc5a expression was delayed and accompanied by apparent pre-mRNA degradation. Intragenic pausing not associated with polyadenylation was also found to regulate and delay Gprc5a expression. Temporal analysis of Nr4a3, Dusp5 and Nfil3 shows that transcription of native IEG genes can proceed at velocities of 3.5 to 4 kilobases/min immediately after activation. Of note, all of the genes studied here also used increased Pol II recruitment as an important regulator of expression. Nevertheless, the generality of co-transcriptional regulation during IEG activation suggests temporal and integrated analysis will often be necessary to distinguish causative from potential rate limiting mechanisms.

  20. Stimulation of α1a adrenergic receptors induces cellular proliferation or antiproliferative hypertrophy dependent solely on agonist concentration.

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    Beilei Lei

    Full Text Available Stimulation of α1aAdrenergic Receptors (ARs is known to have anti-proliferative and hypertrophic effects; however, some studies also suggests this receptor can increase cell proliferation. Surprisingly, we find the α1aAR expressed in rat-1 fibroblasts can produce either phenotype, depending exclusively on agonist concentration. Stimulation of the α1aAR by high dose phenylephrine (>10(-7 M induces an antiproliferative, hypertrophic response accompanied by robust and extended p38 activation. Inhibition of p38 with SB203580 prevented the antiproliferative response, while inhibition of Erk or Jnk had no effect. In stark contrast, stimulation of the α1aAR with low dose phenylephrine (∼10(-8 M induced an Erk-dependent increase in cellular proliferation. Agonist-induced Erk phosphorylation was preceded by rapid FGFR and EGFR transactivation; however, only EGFR inhibition blocked Erk activation and proliferation. The general matrix metalloprotease inhibitor, GM6001, blocked agonist induced Erk activation within seconds, strongly suggesting EGFR activation involved extracellular triple membrane pass signaling. Erk activation required little Ca(2+ release and was blocked by PLCβ or PKC inhibition but not by intracellular Ca(2+ chelation, suggesting Ca(2+ independent activation of novel PKC isoforms. In contrast, Ca(2+ release was essential for PI3K/Akt activation, which was acutely maximal at non-proliferative doses of agonist. Remarkably, our data suggests EGFR transactivation leading to Erk induced proliferation has the lowest activation threshold of any α1aAR response. The ability of α1aARs to induce proliferation are discussed in light of evidence suggesting antagonistic growth responses reflect native α1aAR function.

  1. CRM 1-mediated degradation and agonist-induced down-regulation of beta-adrenergic receptor mRNAs.

    Science.gov (United States)

    Bai, Ying; Lu, Huafei; Machida, Curtis A

    2006-10-01

    The beta1-adrenergic receptor (beta1-AR) mRNAs are post-transcriptionally regulated at the level of mRNA stability and undergo accelerated agonist-mediated degradation via interaction of its 3' untranslated region (UTR) with RNA binding proteins, including the HuR nuclear protein. In a previous report [Kirigiti et al. (2001). Mol. Pharmacol. 60:1308-1324], we examined the agonist-mediated down-regulation of the rat beta1-AR mRNAs, endogenously expressed in the rat C6 cell line and ectopically expressed in transfectant hamster DDT1MF2 and rat L6 cells. In this report, we determined that isoproterenol treatment of neonatal rat cortical neurons, an important cell type expressing beta1-ARs in the brain, results in significant decreases in beta1-AR mRNA stability, while treatment with leptomycin B, an inhibitor of the nuclear export receptor CRM 1, results in significant increases in beta1-AR mRNA stability and nuclear retention. UV-crosslinking/immunoprecipitation and glycerol gradient fractionation analyses indicate that the beta1-AR 3' UTR recognize complexes composed of HuR and multiple proteins, including CRM 1. Cell-permeable peptides containing the leucine-rich nuclear export signal (NES) were used as inhibitors of CRM 1-mediated nuclear export. When DDT1MF2 transfectants were treated with isoproterenol and peptide inhibitors, only the co-addition of the NES inhibitor reversed the isoproterenol-induced reduction of beta1-AR mRNA levels. Our results suggest that CRM 1-dependent NES-mediated mechanisms influence the degradation and agonist-mediated down-regulation of the beta1-AR mRNAs.

  2. Role of hippocampal β-adrenergic and glucocorticoid receptors in the novelty-induced enhancement of fear extinction.

    Science.gov (United States)

    Liu, Jian-Feng; Yang, Chang; Deng, Jia-Hui; Yan, Wei; Wang, Hui-Min; Luo, Yi-Xiao; Shi, Hai-Shui; Meng, Shi-Qiu; Chai, Bai-Sheng; Fang, Qin; Chai, Ning; Xue, Yan-Xue; Sun, Jia; Chen, Chen; Wang, Xue-Yi; Wang, Ji-Shi; Lu, Lin

    2015-05-27

    Fear extinction forms a new memory but does not erase the original fear memory. Exposure to novelty facilitates transfer of short-term extinction memory to long-lasting memory. However, the underlying cellular and molecular mechanisms are still unclear. Using a classical contextual fear-conditioning model, we investigated the effect of novelty on long-lasting extinction memory in rats. We found that exposure to a novel environment but not familiar environment 1 h before or after extinction enhanced extinction long-term memory (LTM) and reduced fear reinstatement. However, exploring novelty 6 h before or after extinction had no such effect. Infusion of the β-adrenergic receptor (βAR) inhibitor propranolol and glucocorticoid receptor (GR) inhibitor RU486 into the CA1 area of the dorsal hippocampus before novelty exposure blocked the effect of novelty on extinction memory. Propranolol prevented activation of the hippocampal PKA-CREB pathway, and RU486 prevented activation of the hippocampal extracellular signal-regulated kinase 1/2 (Erk1/2)-CREB pathway induced by novelty exposure. These results indicate that the hippocampal βAR-PKA-CREB and GR-Erk1/2-CREB pathways mediate the extinction-enhancing effect of novelty exposure. Infusion of RU486 or the Erk1/2 inhibitor U0126, but not propranolol or the PKA inhibitor Rp-cAMPS, into the CA1 before extinction disrupted the formation of extinction LTM, suggesting that hippocampal GR and Erk1/2 but not βAR or PKA play critical roles in this process. These results indicate that novelty promotes extinction memory via hippocampal βAR- and GR-dependent pathways, and Erk1/2 may serve as a behavioral tag of extinction.

  3. Central beta-adrenergic receptors play an important role in the enhancing effect of voluntary exercise on learning and memory in rat.

    Science.gov (United States)

    Ebrahimi, Shima; Rashidy-Pour, Ali; Vafaei, Abbas A; Akhavan, Maziar M

    2010-03-17

    The beneficial effects of physical activity and exercise on brain functions such as improvement in learning and memory are well documented. The aim of this study was to examine the role of the beta-adrenergic system in voluntary exercise-induced enhancement of learning and memory in rat. In order to block the beta-adrenergic receptors, the animals were received propranolol (a beta-blocker), or nadolol (a peripherally acting beta-blocker) before each night of five consecutive nights of exercise. Then their learning and memory were tested on the water maze task using a two-trials-per-day for 5 consecutive days. A probe trial was performed 2 days after the last training day. Our results showed that propranolol, but not nadolol reversed the exercise-induced improvement in learning and memory in rat. Our findings indicate that central beta-adrenergic receptors play an important role in mediating the beneficial effects of voluntary exercise on learning and memory.

  4. Mechanism of allosteric regulation of β2-adrenergic receptor by cholesterol

    DEFF Research Database (Denmark)

    Manna, Moutusi; Niemelä, Miia; Tynkkynen, Joona

    2016-01-01

    ) - a prototypical G protein-coupled receptor - is modulated by cholesterol in an allosteric fashion. Extensive atomistic simulations show that cholesterol regulates b2AR by limiting its conformational variability. The mechanism of action is based on the binding of cholesterol at specific high-affinity sites located...... near the transmembrane helices 5-7 of the receptor. The alternative mechanism, where the β2AR conformation would be modulated by membrane-mediated interactions, plays only a minor role. Cholesterol analogues also bind to cholesterol binding sites and impede the structural flexibility of β2AR, however...... cholesterol generates the strongest effect. The results highlight the capacity of lipids to regulate the conformation of membrane receptors through specific interactions....

  5. Mivazerol, a novel compound with high specificity for alpha 2 adrenergic receptors: binding studies on different human and rat membrane preparations.

    Science.gov (United States)

    Noyer, M; de Laveleye, F; Vauquelin, G; Gobert, J; Wülfert, E

    1994-03-01

    Mivazerol, 3-[1(H-imidazol-4-yl)methyl]-2-hydroxybenzamide hydrochloride, a new potential anti-ischemic drug designed by UCB S.A. Pharma Sector, has been studied in binding experiments on adrenergic, dopaminergic, serotoninergic, muscarinic and idazoxan binding sites. Our results indicate that this compound displays high affinity and marked specificity for alpha 2 adrenoceptors. Mivazerol displaced the binding of the alpha 2 adrenoceptor antagonist [3H]RX 821002 to the alpha 2A adrenoceptors in human frontal cortex membranes with an apparent Ki value of 37 nM. The competition curve was shallow (nH = 0.55), suggesting that this compound acts as an alpha 2 adrenergic agonist. Mivazerol was also a potent competitor for [3H]RX 821002 binding to human platelet membranes (containing alpha 2A adrenoceptors) and rat kidney membranes (75% of the alpha 2 adrenoceptors of the alpha 2B subtype), indicating that this compound is not alpha 2 adrenoceptor subtype selective. Equilibrium dissociation constants for alpha 1 adrenoceptors (displacement of [3H]prazosin) and 5-HT1A receptors (displacement of [3H]rauwolscine) were respectively about 120 times (Ki = 4.4 microM) and 14 times (Ki = 530 nM) higher than that for the alpha 2 adrenoceptors. Equilibrium dissociation constants were approximately 1000 times higher for all other receptors tested in this study; namely beta 1 and beta 2 adrenoceptors, D1- and D2-dopamine receptors, M1-, M2- and M3-muscarinic receptors, 5-HT2 receptors and non-adrenergic idazoxan binding sites.

  6. Crystal structure of the β2 adrenergic receptor-Gs protein complex

    DEFF Research Database (Denmark)

    Rasmussen, Søren Gøgsig Faarup; DeVree, Brian T; Zou, Yaozhong;

    2011-01-01

    G protein-coupled receptors (GPCRs) are responsible for the majority of cellular responses to hormones and neurotransmitters as well as the senses of sight, olfaction and taste. The paradigm of GPCR signalling is the activation of a heterotrimeric GTP binding protein (G protein) by an agonist...

  7. 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

    Structural analysis of G-protein-coupled receptors (GPCRs) for hormones and neurotransmitters has been hindered by their low natural abundance, inherent structural flexibility, and instability in detergent solutions. Here we report a structure of the human beta2 adrenoceptor (beta2AR), which...

  8. Fluorescence histochemical study of the localisation and distribution of beta-adrenergic receptor sites in the spinal cord and cerebellum of the chicken.

    Science.gov (United States)

    Bondok, A A; Botros, K G; el-Mohandes, E A

    1988-10-01

    The distribution of beta-adrenergic receptor sites has been studied in chicken spinal cord and cerebellum using a fluorescent analogue of propranolol, 9-amino-acridin-propranolol (9-AAP). In the cervical and lumbar regions of the spinal cord, beta-adrenoceptor sites were concentrated on cell bodies of alpha-motor neurons of the dorsolateral and ventrolateral nuclear groups of the ventral horn. In the thoracic region, they were present on cell bodies of the preganglionic sympathetic nucleus (dorsal commissural nucleus). In the dorsal horn, the receptor sites were present mainly on cell bodies of columna dorsalis magnocellularis. Sparse distribution of fluorescence was present in other regions of the gray matter. In the cerebellum, a dense distribution of beta-adrenergic receptor sites was observed on Purkinje cell bodies and their apical dendrites. Sparse distribution of receptor sites was present on fine ramifications of Purkinje cell dendrites in the molecular layer. Receptor sites were absent in the granule cell layer and the white matter. These observations indicate that alpha-motor neurons, preganglionic sympathetic neurons, neurons of columna dorsalis magnocellularis, and Purkinje cells are adrenoceptive, while granule cells are non-adrenoceptive.

  9. Effect of {beta}{sub 1} adrenergic receptor blockade on myocardial blood flow and vasodilatory capacity

    Energy Technology Data Exchange (ETDEWEB)

    Boettcher, M.; Czernin, J.; Sun, K. [Univ. of California, Los Angeles, CA (United States)] [and others

    1997-03-01

    The {beta}{sub 1} receptor blockade reduces cardiac work and may thereby lower myocardial blood flow (MBF) at rest. The effect of {beta}{sub 1} receptor blockade on hyperemic MBF is unknown. To evaluate the effect of selective {beta}{sub 1} receptor blockade on MBF at rest and during dipyridamole induced hyperemia, 10 healthy volunteers (8 men, 2 women, mean age 24 {+-} 5 yr) were studied using {sup 13}N-ammonia PET (two-compartment model) under control conditions and again during metoprolol (50 mg orally 12 hr and 1 hr before the study). The resting rate pressure product (6628 {+-} 504 versus 5225 {+-} 807) and heart rate (63 {+-} 6-54 {plus_minus} 5 bpm) declined during metoprolol (p < 0.05). Similarly, heart rate and rate pressure product declined from the baseline dipyridamole study to dipyridamole plus metoprolol (p < 0.05). Resting MBF declined in proportion to cardiac work by approximately 20% from 0.61 {+-} 0.09-0.51 {+-} 0.10 ml/g/min (p < 0.05). In contrast, hyperemic MBF increased when metoprolol was added to dipyridamole (1.86 {plus_minus} 0.27 {+-} 0.45 ml/g/min; p<0.05). The decrease in resting MBF together with the increase in hyperemic MBF resulted in a significant increase in the myocardial flow reserve during metoprolol (3.14 {+-} 0.80-4.61 {+-} 0.68; p<0.01). The {beta}{sub 1} receptor blockade increases coronary vasodilatory capacity and myocardial flow reserve. However, the mechanisms accounting for this finding remain uncertain. 32 refs., 2 figs., 2 tabs.

  10. Pharmacological tolerance to alpha 1-adrenergic receptor antagonism mediated by terazosin in humans.

    OpenAIRE

    Vincent, J; Dachman, W; Blaschke, T F; Hoffman, B. B.

    1992-01-01

    Chronic administration of alpha 1-receptor antagonists is associated with loss of clinical efficacy, especially in congestive heart failure, although the mechanism is uncertain. To evaluate changes in venous alpha 1-adrenoceptor responsiveness during chronic alpha 1-adrenoceptor blockade, dose-response curves to phenylephrine and angiotensin II were constructed in 10 healthy subjects before, during, and after administration of terazosin 1 mg orally for 28 d. Terazosin initially shifted the do...

  11. Adenylyl cyclase type 6 overexpression selectively enhances beta-adrenergic and prostacyclin receptor-mediated inhibition of cardiac fibroblast function because of colocalization in lipid rafts.

    Science.gov (United States)

    Liu, Xiaoqiu; Thangavel, Muthusamy; Sun, Shu Qiang; Kaminsky, Joseph; Mahautmr, Penden; Stitham, Jeremiah; Hwa, John; Ostrom, Rennolds S

    2008-06-01

    Cardiac fibroblasts produce and degrade extracellular matrix and are critical in regulating cardiac remodeling and hypertrophy. Fibroblasts are activated by factors such as transforming growth factor beta and inhibited by agents that elevate 3',5'-cyclic adenosine monophosphate (cAMP) levels. cAMP signal generation and response is known to be compartmentalized in many cell types in part through the colocalization of receptors and specific adenylyl cyclase isoforms in lipid rafts and caveolae. The present study sought to define the localization of key G protein-coupled receptors with adenylyl cyclase type 6 (AC6) in lipid rafts of rat cardiac fibroblasts and to determine if this colocalization was functionally relevant. We found that cardiac fibroblasts produce cAMP in response to agonists for beta-adrenergic (isoproterenol), prostaglandin EP2 (butaprost), adenosine (adenosine-5'-N-ethylcarboxamide, NECA), and prostacyclin (beraprost) receptors. Overexpression of AC6 increased cAMP production stimulated by isoproterenol and beraprost but not by butaprost or NECA. A key function of fibroblasts is the production of collagen. Isoproterenol- and beraprostmediated inhibition of collagen synthesis was also enhanced by AC6 overexpression, while inhibition by butaprost and NECA were unaltered. Lipid raft fractions from cardiac fibroblasts contain the preponderance of beta-adrenergic receptors and AC6 but exclude EP2 receptors. While we could not determine the localization of native prostacyclin receptors, we were able to determine that epitope-tagged prostanoid IP receptors (IPR) expressed in COS7 cells did localize, in part, in lipid raft fractions. These findings indicate that IP receptors are expressed in lipid rafts and can activate raft-localized AC isoforms. AC6 is completely compartmentized in lipid raft domains where it is activated solely by coresident G protein-coupled receptors to regulate cardiac fibroblast function.

  12. Determinants Present in the Receptor Carboxy Tail Are Responsible for Differences in Subtype-Specific Coupling of β-Adrenergic Receptors to Phosphoinositide 3-Kinase

    Directory of Open Access Journals (Sweden)

    Julie Simard

    2009-01-01

    Full Text Available An agonist-occupied β2-adrenergic receptor (β2-AR recruits G protein receptor kinase-2 (GRK2 which is recruited to the membrane. Thus, the physical proximity of activated β2-AR and PI-3K allows the activation of the latter. In contrast, it has been observed that the β1-AR is unable to activate the PI-3K/Akt pathway. We hypothesized that the difference might be due to molecular determinants present in the carboxy termini of the two β-AR subtypes. Using transiently transfected HEK 293 cells expressing either β1- or β2-AR, we also observed that in presence of an agonist, β2-AR, but not β1-AR, is able to activate the PI-3K/Akt pathway. Switching the seventh transmembrane domain and the carboxy tail between the two receptors reverses this phenotype; that is, β1×β2-AR can activate the PI-3K/Akt pathway whereas β2×β1-AR cannot. Pretreatment with pertussis toxin abolished the activation of PI-3K by β2- or β1×β2-AR stimulation. Ligand-mediated internalization of the β2-AR induced by a 15-minute stimulation with agonist was abolished in the presence of a dominant negative of PI-3K or following pertussis toxin pretreatment. These results indicate that the subtype-specific differences in the coupling to PI-3K/Akt pathway are due to molecular determinants present in the carboxy tail of the receptor and further that β2-AR activates PI-3K via a pertussis toxin-sensitive mechanism.

  13. Roles of adrenergic α1 and dopamine D1 and D2 receptors in the mediation of the desynchronization effects of modafinil in a mouse EEG synchronization model.

    Directory of Open Access Journals (Sweden)

    Chang-Rui Chen

    Full Text Available BACKGROUND: Synchronized electroencephalogram (EEG activity is observed in pathological stages of cognitive impairment and epilepsy. Modafinil, known to increase the release of catecholamines, is a potent wake-promoting agent, and has shown some abilities to desynchronize EEG,but its receptor mechanisms by which modafinil induces desynchoronization remain to be elucidated. Here we used a pharmacological EEG synchronization model to investigate the involvement of adrenergic α1 receptors (R, α1R and dopamine (DA D1 and D2 receptors (D1Rs and D2Rs on modafinil-induced desynchronization in mice. METHODOLOGY/PRINCIPAL FINDINGS: Mice were treated with cholinergic receptor antagonist scopolamine and monoamine depletor reserpine to produce experimental EEG synchronization characterized by continuous large-amplitude synchronized activity, with prominent increased delta and decreased theta, alpha, and beta power density. The results showed that modafinil produced an EEG desynchronization in the model. This was characterized by a general decrease in amplitude of all the frequency bands between 0 and 20 Hz, a prominent reduction in delta power density, and an increase in theta power density. Adrenergic α1R antagonist terazosin (1 mg/kg, i.p. completely antagonized the EEG desynchronization effects of modafinil at 90 mg/kg. However, DA D1R and D2R blockers partially attenuated the effects of modafinil. The modafinil-induced decrease in the amplitudes of the delta, theta, alpha, and beta waves and in delta power density were completely abolished by pretreatment with a combination of the D1R antagonist SCH 23390 (30 µg/kg and the D2R antagonist raclopride (2 mg/kg, i.p.. CONCLUSIONS/SIGNIFICANCE: These results suggest that modafinil-mediated desynchronization may be attributed to the activation of adrenergic α1R, and dopaminergic D1R and D2R in a model of EEG synchronization.

  14. Epinephrine effects on mitochondrial Krebs cycle are not mediated by typical adrenergic receptors in isolated rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Mohan, C.; Memon, R.A.; Bessman, S.P. (Univ. of Southern California, Los Angeles (United States))

    1990-02-26

    Oxidation of 2,3-{sup 14}C succinate (suc) carbons in the intra-mitochondrial Krebs cycle was used as a probe to investigate the effects of epinephrine (epi) on isolated rat hepatocytes. Hepatocytes were incubated at 30{degrees}C in Krebs-Henseleit bicarbonate buffer, pH 7.4, with 0.5 mM concentration of each of the 20 natural amino acids, 0.5 mm concentration of each of the 20 natural amino acids, 2,3-{sup 14}C suc and epi (10 uM), phenylephrine (pheni) (10uM) or isoproterenol (10 uM). Epi and phepi caused a significant increase in {sup 14}CO{sub 2} formation from 2,3-{sup 14}C suc, however, phentolamine, an {infinity}-antagonist, failed to inhibit this increased oxidation of suc carbons. Isoproterenol had no effect on hepatocyte metabolism and propranolol, a {beta}-antagonist, failed to cause any reduction in basal or epi stimulated oxidation of 2,3-{sup 14}C carbons. Unlike insulin, neither epi nor phepi had any significant effect on the anabolic utilization of suc carbons for protein or lipid synthesis. Anabolic channeling of Krebs cycle intermediates into amino acids was reduced by epi treatment of hepatocytes. Although epi treatment can enhance the oxidation of substrate through the Krebs cycle reactions, only insulin is capable of channeling these substrates into anabolic reactions. Data presented also suggest that epi effects on mitochondrial Krebs cycle oxidation are mediated through an atypical {infinity}-adrenergic receptor which is unresponsive to inhibition by non-selective {infinity}-antagonists.

  15. Propranolol represses infantile hemangioma cell growth through the β2-adrenergic receptor in a HIF-1α-dependent manner.

    Science.gov (United States)

    Li, Peng; Guo, Zhengtuan; Gao, Ya; Pan, Weikang

    2015-06-01

    Propranolol, as a non-selective blocker of the β-adrenergic receptor (AR), is utilised as the first-line treatment for infantile hemangiomas. However, the underlying mechanism remains poorly understood. The present study was designed to investigate the molecular basis of propranolol on the regression of infantile hemangiomas using a proliferating infantile hemangioma-derived endothelial cell line. In infantile hemangioma patients, we found that propranolol significantly decreased the expression levels of the hypoxia inducible factor (HIF)-1α in serum and urine, as well as in hemangioma tissues. In vitro analysis revealed that propranolol reduces the expression of HIF-1α in hemangioma cells in a dose- and time-dependent manner, mainly by acting on β2-AR. Interestingly, it was observed that overexpression of HIF-1α apparently abrogated the inhibitory effects of propranolol on vascular endothelial growth factor (VEGF) expression and cell growth. Our data further demonstrated that propranolol inhibited the signal transducer and activator of transcription 3 (STAT3), a critical oncogenic signaling molecule, and the anti-apoptotic protein Bcl-2. Additionally, overexpression of HIF-1α significantly reversed the inhibitory effects of propranolol on STAT3 signaling. In a mouse xenograft hemangioma model, overexpression of HIF-1α significantly attenuated the therapeutic effects of propranolol and inhibited propranolol-induced hemangioma cell apoptosis. Moreover, the protein levels of VEGF, phosphorylated STAT3, total STAT3 and Bcl-2 were significantly upregulated by HIF-1α overexpression in propranolol-treated nude mice bearing hemangiomas. Collectively, our data provide evidence that propranolol may regress infantile hemangiomas by suppressing VEGF and STAT3 signaling pathways in an HIF-1α-dependent manner.

  16. Norepinephrine depresses the immunity and disease-resistance ability via α1- and β1-adrenergic receptors of Macrobrachium rosenbergii.

    Science.gov (United States)

    Chang, Chin-Chyuan; Hung, Ming-Di; Cheng, Winton

    2011-06-01

    In this study, we determined the effects of norepinephrine (NE) on immunity and the pathway of its function in the freshwater giant prawn, Macrobrachium rosenbergii. The total hemocyte count (THC), differential hemocyte count (DHC), phenoloxidase activity, respiratory bursts, superoxide dismutase (SOD) activity, phagocytic activity, and clearance efficiency in response to the pathogen, Lactococcus garvieae, were measured when the freshwater giant prawn, M. rosenbergii (16.2±2.1 g) was individually injected with saline or NE at 0.5, 5.0, and 50.0 pmol prawn(-1). Results showed that semi-granular cells, respiratory bursts and phagocytic activity at 2 h, PO activity and clearance efficiency from 2 to 4 h, THC at 8 h, and SOD activity from 4 to 8 h significantly decreased, but hyaline cells at 2 h, and respiratory bursts at 8 h had significantly increased after injection of NE at 50.0 pmol prawn(-1). In prawns that had received 5.0 pmol NE prawn(-1), the PO activity had decreased at 2 h, SOD activity at 8 h, and the clearance efficiency at 2 h. PO activity had decreased at 2 h after prawns had received 0.5 pmol NE prawn(-1). All of the immune parameters had returned to control values by 16 h after receiving NE. However, no significant differences were observed in the granular cells during the experimental period. An injection of NE also significantly increased the mortality of prawns challenged with L. garvieae, which appeared to be dose dependent. In another experiment, NE co-injected with prazosin, metoprolol, or propranolol significantly decreased the mortality of challenged prawns, especially when co-injected with prazosin and metoprolol. These results suggest that stress-inducing NE suppresses the immune system, which in turn promotes the susceptibility of M. rosenbergii to L. garvieae via both α1- and β1-adrenergic receptors.

  17. Alterations in the oxygen deficit-oxygen debt relationships with beta-adrenergic receptor blockade in man.

    Science.gov (United States)

    Hughson, R L

    1984-04-01

    The effects of beta-adrenergic receptor blockade (100 mg oral metoprolol) or matched placebo on gas exchange kinetics were studied in six males. Ventilation and gas exchange were monitored in four transitions for each treatment from loadless pedalling (0 W) to a selected work rate (100 W) and back to 0 W. Breath-by-breath data were averaged for analysis. Oxygen uptake (VO2) kinetics were significantly slowed at the onset of exercise and recovery by beta-blockade. This resulted in larger oxygen deficit and oxygen debt (671 +/- 115, 586 +/- 87 ml O2, respectively) for beta-blockade than for placebo (497 +/- 87, 474 +/- 104 ml O2). In addition, oxygen deficit was significantly larger than oxygen debt during beta-blockade tests. These results can be explained by greater utilization of oxygen and creatine phosphate stores as well as anaerobic glycolysis at the onset of 100 W exercise with beta-blockade. Carbon dioxide output (VCO2) kinetics were significantly slowed by beta-blockade only at the onset of exercise. Expired ventilation (VE) kinetics were not affected by beta-blockade. At 0 W, VE was significantly reduced by beta-blockade. Heart rate was lower at all times with beta-blockade. Kinetics of heart rate were not affected. These data for VO2 kinetics at the start and end of exercise indicate that even in moderate-intensity exercise, lactic acid production can contribute significantly to energy supply. The use of the term ' alactic ' to describe the deficit and debt associated with this exercise is not appropriate.

  18. β2肾上腺素能受体基因Gln27/Glu多态性与蒙古族原发性高血压的研究%Study of the β2-Adrenergic Receptor Gene Gln27/Glu Polymorphisms and Essential Hypertension in Mongolian Population

    Institute of Scientific and Technical Information of China (English)

    张晓云; 李云霞; 魏芳婧; 娜荣; 徐力; 阴淑莹

    2012-01-01

    目的 检测蒙古族原发性高血压(EH)人群中β2肾上腺素能受体基因Gln27/Glu多态性,探讨其与蒙古族人群EH和其他心血管病危险因素的关系.方法 选择蒙古族EH患者105例为观察组,另外选取蒙古族健康体检者102例为对照组,通过聚合酶链反应确定基因型,并测定所有患者的体质量指数(BMI)、空腹血三酰甘油、总胆固醇、低密度脂蛋白胆固醇、收缩压/舒张压、空腹血糖、尿酸等.结果 EH组和对照组Gln27/Glu多态性的基因型频率和等位基因频率比较差异无统计学意义(P>0.05),Gln27/Glu基因型个体的BMI显著高于Gln27/Gln基因型个体(P<0.05),三酰甘油、总胆固醇、低密度脂蛋白胆固醇、尿酸、空腹血糖等在三种基因型之间差异无统计学意义(P>0.05).结论 Gln27/Glu基因可能不是蒙古族EH的易患基因,该基因突变可能与肥胖有关.%Objective To study essential hypertension β-adrenergic rereptor( ADRB2 )gene Cln27/ Clu polymoiphism in Mongolian population, to test the hypothesis that polymorphism in the ADRB2 sene Cln27/Clu is associated with essential hypeitension( EH ) and other cardiovascular disease risk factors in Mongolian population. Methods 105 cases( observation group )of Mongolian patients with EH and 102 cases ( control group )of normal Mongolian were enrolled in this study. Targeted genotypes were determined by poly-merase chain reaction, and subjects were measured body mass index( BMI), lasting triglyceride( TC ), total cholesteioK TC ),low-density lipopiotein cholesteioK LDL-C ), and systolic/diastolic blood pressure,fasting glucose,and uric acid. Results Gln27/Glu polymoiphism senotypic and allele frequencies were not significantly different between the EH group and the control group(P >0. 05 ). BMI in individuals with Gln27/Glu genotype was significantly higher than the individuals with Gln27/Gln genotypes( P < 0. 05 ). And tiiglycei-ides,total cholesterol

  19. 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.

  20. Genetic variation in the beta2-adrenergic receptor but not catecholamine-O-methyltransferase predisposes to chronic pain: results from the 1958 British Birth Cohort Study.

    Science.gov (United States)

    Hocking, Lynne J; Smith, Blair H; Jones, Gareth T; Reid, David M; Strachan, David P; Macfarlane, Gary J

    2010-04-01

    More than 1 in 10 adults in the general population experience chronic widespread body pain (CWP), which lies at one end of a continuous spectrum of pain ranging in both severity and duration. Neuroendocrine factors can modify the effect of known psychological and psychosocial risk factors for progression along the spectrum of pain and development of CWP, and genetic variants that affect neuroendocrine and neural processing potentially affect susceptibility to chronic pain development. We have examined variants across genes encoding the beta2-adrenergic receptor (ADRB2) and catecholamine-O-methyltransferase (COMT) - key neuroendocrine signalling factors - in a large population-based sample to determine whether these may be involved in pain progression and CWP development. A nested association study was conducted using individuals from the 1958 British Birth Cohort Study who had been assessed for pain status. Genotypes were available for nine single nucleotide polymorphisms (SNPs) across ADRB2 and 11 SNPs across COMT. ADRB2 SNPs rs12654778 and rs1042713 were associated either with CWP alone (p=0.02 for both) or with position along pain spectrum (pain status; p=0.04). Common functional ADRB2 haplotype combinations were also associated with pain status (p(model)=0.002) and, further, with both extent and duration of pain (p(model)=0.003 and p(model)=0.002, respectively). There were no associations of either CWP or pain status with COMT genotypes or haplotypes. These results are the first to suggest that functional ADRB2 variants are involved in regulating pain status at a population level. A role for COMT in chronic pain development was not identified, though could not be excluded.

  1. Age-associated alternations in cardiac β-adrenergic receptor signaling

    Institute of Scientific and Technical Information of China (English)

    Jing MA; Shiwen WANG; Ruiping XIAO

    2005-01-01

    During aging, cardiac contractile response to β-AR stimulation is decreased in humans and animal models. Recent studies demonstrate that the positive inotropic effects of both β1-AR and β2-AR stimulation are significantly decreased with aging.This is accompanied by decreases in both β-AR subtype densities and a reduction in membrane adenylyl cyclase activity. However,neither G protein-coupled receptor kinases (GRKs) nor inhibitory G proteins (Gi) appears to contribute to the age-associated reduction in the β-AR modulation of contraction. Thus, while both aging and chronic heart failure exhibit a diminution in cardiac β-AR responsiveness, only heart failure exhibits increased GRK-mediated desensitization ofβ-Ars and an upregulation of Gi proteins.

  2. Purification and characterization of the human platelet. cap alpha. /sub 2/-adrenergic receptor

    Energy Technology Data Exchange (ETDEWEB)

    Shreeve, S.M.; Kerlavage, A.R.; Fraser, C.M.; Mariani, A.P.; Venter, J.C.

    1986-05-01

    The ..cap alpha../sub 2/-receptor (..cap alpha../sub 2/-R) from human platelets has been purified to homogeneity using a four step process. An affinity column was prepared by coupling p-aminoclonidine to CH-Sepharose 4B via the p-NH/sub 2/ group. Digitonin solubilized ..cap alpha../sub 2/-R bound to the affinity matrix were eluted with 100 ..mu..M phentolamine and directly applied to a DEAE-Sepharose column. Bound receptors were eluted with a linear gradient of 0-500 mM NaCl, pooled and chromatographed on HPLC size exclusion columns. Three peaks of ..cap alpha../sub 2/-R binding were eluted from HPLC columns (t = 33, 42, 47 min). Radioiodination of HPLC eluates and analysis by SDS-PAGE indicated that ..cap alpha../sub 2/-R binding was associated with a 75-85 kDa protein. These data suggest that the ..cap alpha../sub 2/-R may exist in monomeric and oligomeric forms in the purified state and support previous target size data which indicate that the ..cap alpha../sub 2/-R exists as a dimer in the native membrane. The pure radioiodinated ..cap alpha../sub 2/-R (77-85 kDa) is a glycoprotein with terminal sialic acid or N-acetylglucosamine residues and has a pI of 4.1 on column isoelectric focusing. These data are consistent with those previously reported on the partially purified ..cap alpha../sub 2/-R. Electron micrographs confirm the oligomeric nature and size of the pure ..cap alpha../sub 2/-R.

  3. Acute exposure to long-chain fatty acids impairs {alpha}2-adrenergic receptor-mediated antilipolysis in human adipose tissue.

    Science.gov (United States)

    Polak, Jan; Moro, Cédric; Bessière, David; Hejnova, Jindra; Marquès, Marie A; Bajzova, Magda; Lafontan, Max; Crampes, Francois; Berlan, Michel; Stich, Vladimir

    2007-10-01

    The acute in vitro and in vivo effects of long-chain fatty acids (LCFAs) on the regulation of adrenergic lipolysis were investigated in human adipose tissue. The effect of a 2 h incubation, without or with LCFA (200 mumol/l), on basal and hormonally induced lipolysis was tested in vitro on isolated fat cells. The lipolytic response to epinephrine was enhanced by suppression of the antilipolytic alpha(2)-adrenergic effect. Then, healthy lean and obese male subjects performed a 45 min exercise bout at 50% of their heart rate reserve either after an overnight fast or 3 h after a high-fat meal (HFM: 95% fat, 5% carbohydrates). Subcutaneous adipose tissue lipolysis was measured by microdialysis in the presence or absence of an alpha-antagonist (phentolamine). In vivo, a HFM increased plasma levels of nonesterified fatty acids in lean and obese subjects. In both groups, the HFM did not alter hormonal responses to exercise. Under fasting conditions, the alpha(2)-adrenergic antilipolytic effect was more pronounced in obese than in lean subjects. The HFM totally suppressed the alpha(2)-adrenergic antilipolytic effect in lean and obese subjects during exercise. LCFAs per se, in vitro as well as in vivo, suppress alpha(2)-adrenergic-mediated antilipolysis in adipose tissue. LCFA-mediated suppression of antilipolytic pathways represents another mechanism whereby a high fat content in the diet might increase adipose tissue lipolysis.

  4. Pharmacological tolerance to alpha 1-adrenergic receptor antagonism mediated by terazosin in humans.

    Science.gov (United States)

    Vincent, J; Dachman, W; Blaschke, T F; Hoffman, B B

    1992-01-01

    Chronic administration of alpha 1-receptor antagonists is associated with loss of clinical efficacy, especially in congestive heart failure, although the mechanism is uncertain. To evaluate changes in venous alpha 1-adrenoceptor responsiveness during chronic alpha 1-adrenoceptor blockade, dose-response curves to phenylephrine and angiotensin II were constructed in 10 healthy subjects before, during, and after administration of terazosin 1 mg orally for 28 d. Terazosin initially shifted the dose-response curve of phenylephrine to the right, with a significant increase in ED50 for phenylephrine from a control value of 102 to 759 ng/min on day 1 of terazosin (P < 0.001). However, by day 28, the dose-response curve had shifted back towards baseline with an ED50 of 112 ng/min. After discontinuing terazosin, the ED50 for phenylephrine remained near the baseline value, indicating no evidence of supersensitivity to phenylephrine. There was no change in responsiveness to angiotensin II during the course of treatment with terazosin. Plasma terazosin concentrations were stable throughout the period of drug administration. The mean Kd of terazosin was estimated as 11 +/- 15 nM in the first few days of treatment. This study demonstrates that pharmacological tolerance to the alpha 1-adrenoceptor blocking action of terazosin occurs in man and may be responsible for loss in efficacy with chronic therapy. PMID:1358918

  5. Apparent histological changes of adipocytes after treatment with CL 316,243, a ß-3-adrenergic receptor agonist

    Directory of Open Access Journals (Sweden)

    Ghorbani M

    2015-02-01

    Full Text Available Masoud Ghorbani,1,2,* Shahram Teimourian,3,* Reza Farzad,4 Nabiollah Namvar Asl4 1Research and Development Department, Pasteur Institute of Iran, Tehran, Iran; 2Department of Biochemistry, University of Ottawa, Ottawa, ON, Canada; 3Department of Medical Genetics, Iran University of Medical Sciences, Tehran, Iran; 4Department of Animal Science, Pasteur Institute of Iran, Research and Production Complex, Karaj, Iran*These authors contributed equally to this work Background and objectives: The objective of this experiment was to study the effect of CL 316,243 (CL (a highly selective ß3-adrenergic receptor agonist on cellular changes occurring in retroperitoneal white adipose tissue (RWAT of lean and obese rats. Methods: Ten-month-old lean and obese Zucker rats were implanted subcutaneously with osmotic mini-pumps, infusing either saline or CL (1 mg/kg body weight/day for 4 weeks. Results: There was no effect of CL on food intake. However, the resting metabolic rate in lean and obese rats increased by 55% and 96% per rat, respectively. Total RWAT weight decreased in both lean and obese rats under influence of CL treatment by 65% and 38%, respectively. Total body weight and body fat were lower in CL treated rats. Detection of uncoupling protein 1(UCP1 in RWAT was confirmed qualitatively by both immunohistochemistry and immunofluorescence using a rabbit anti rat UCP1 antibody which showed the appearance of a marked increase of this protein in the adipose tissue. Stained semi-thin sections (0.5 µm also demonstrated abundant nuclei in multilocular adipocytes, in endothelial cells associated with the vasculature, and in interstitial cells. In CL-treated obese rats, a clustering of several multilocular cells around the periphery of a white adipocyte was seen. Conclusion: These results indicate that treatment of both lean and obese Zucker rats with CL induces extensive remodeling of RWAT that includes shrinkage of white adipose tissue, appearance of

  6. β-arrestin and β-adrenergic Receptor%β-arrestin与β-肾上腺素受体

    Institute of Scientific and Technical Information of China (English)

    杨承志; 李子健

    2012-01-01

    The Nobel Prize in Chemistry 2012 was awarded jointly to Robert J. Lefkowitz and Brian K. Kobilka "for studies of G-protein-coupled receptors". Robert J. Lefkowitz discovered β-arrestinl more than 20 years ago, when he studied the mechanism of β-AR (p-adrenergic receptor) desensitization, and proved that it involves in the desensitization, internalization and degradation of β-AR in his subsequent researches. More recently, new evidence has revealed the "biased agonism" of β-arrestin dependent signal pathway of β-AR, which is independent of G protein. Excitingly, this biased signaling was suggested to confer cardioprotection. In addition, β-AR blockers were discovered and widely used in the pharmacotherapy of cardiovascular diseases among many other β-AR targeted cardiovascular drugs, which was a breakthrough in the 20th century. However, most of these drugs take effect only by regulating the β-AR itself and block all of the signal pathways and functions, including both the pathological signaling and effect induced by the increased stimulation of β-AR and the normal physiological ones, which leads to some severe adverse reactions. Therefore, it will be a great progress in the treatment of cardiovascular diseases to develop the drug that can both selectively block the harmful signaling and effect and activate the beneficial physiological signaling (such as the β-arrestin signaling) of β-AR. The research and development of ligand drug for β-AR will focus on its highly selective downstream signal pathways. This article is to review the discovery of the β-arrestin and its interaction with β-AR, to offer a reference for the pharmacotherapy of cardiovascular diseases.%2012年度诺贝尔化学奖授予了美国科学家罗伯特·莱夫科维茨(Robert J.Lefkowitz)和布莱恩·克比尔卡(Brian K.Kobilka),以表彰他们在G蛋白偶联受体研究中的贡献.从Robert J.Lefkowitz最初研究β-肾上腺素受体(β-adrenergic receptor,β-AR

  7. Intracoronary genistein acutely increases coronary blood flow in anesthetized pigs through beta-adrenergic mediated nitric oxide release and estrogenic receptors.

    Science.gov (United States)

    Grossini, Elena; Molinari, Claudio; Mary, David A S G; Uberti, Francesca; Caimmi, Philippe Primo; Surico, Nicola; Vacca, Giovanni

    2008-05-01

    Various studies have suggested that the phytoestrogen genistein has beneficial cardioprotective and vascular effects. However, there has been scarce information regarding the primary effect of genistein on coronary blood flow and its mechanisms including estrogen receptors, autonomic nervous system, and nitric oxide (NO). The present study was planned to determine the primary effect of genistein on coronary blood flow and the mechanisms involved. In anesthetized pigs, changes in left anterior descending coronary artery caused by intracoronary infusion of genistein at constant heart rate and arterial pressure were assessed using ultrasound flowmeters. In 25 pigs, genistein infused at 0.075 mg/min increased coronary blood flow by about 16.3%. This response was graded in a further five pigs by increasing the infused dose of the genistein between 0.007 and 0.147 mg/min. In the 25 pigs, blockade of cholinergic receptors (iv atropine; five pigs) and alpha-adrenergic receptors (iv phentolamine; five pigs) did not abolish the coronary response to genistein, whose effects were prevented by blockade of beta(2)-adrenergic receptors (iv butoxamine; five pigs), nitric oxide synthase (intracoronary N(omega)-nitro-L-arginine methyl ester; five pigs) and estrogenic receptors (ERs; ERalpha/ERbeta; intracoronary fulvestrant; five pigs). In porcine aortic endothelial cells, genistein induced the phosphorylation of endothelial nitric oxide synthase and NO production through ERK 1/2, Akt, and p38 MAPK pathways, which was prevented by the concomitant treatment by butoxamine and fulvestrant. In conclusion, genistein primarily caused coronary vasodilation the mechanism of which involved ERalpha/ERbeta and the release of NO through vasodilatory beta(2)-adrenoreceptor effects.

  8. Effect of β3-adrenergic receptor gene Trp64Arg polymorphism on uric acid levels in a Chinese male type 2 diabetes mellitus population%β3肾上腺素受体基因Trp64Arg多态性与中国男性2型糖尿病患者合并高尿酸血症的相关性研究

    Institute of Scientific and Technical Information of China (English)

    黄琼; 张留福; 程雁; 司力; 魏伟

    2013-01-01

    目的:探讨中国人群男性2型糖尿病患者中β3肾上腺素受体基因Trp64Arg多态性与高尿酸血症的相关性.方法:196名高尿酸血症的2型糖尿病患者和196名正常尿酸水平的2型糖尿病患者进行基因分型.检测体重指数、腰臀比、收缩压、舒张压、血尿酸、肌酐、尿素氮、甘油三酯、低密度脂蛋白胆固醇脂、高密度脂蛋白胆固醇脂、空腹血糖和餐后血糖的水平.结果:高尿酸血症组中,携带不同β3肾上腺素受体Trp64Arg基因型的2型糖尿病患者其尿酸水平有统计学差异,且呈基因剂量效应[CC组(599.53±113.70) vs CT组(529.78±81.10) vs TT组(507.33±74.27),P<0.01].在该研究中,Trp64Arg TC+CC基因型患者的血尿酸水平亦显著高于TT基因型组p(557.95±99.91) vs (503.47±69.40) μmol/L,P<0.01].结论:β3肾上腺素受体基因Trp64Arg多态性与2型糖尿病合并高尿酸血症的具有相关性.%AIM:To investigate the association of β3-adrenergic receptor gene Trp64Arg polymorphism with hyperuricemia in a Chinese male type 2 diabetes mellitus patients population.METHODS:196 hyperuricemic and 196 normouricemic male subjects were genotyped in this study.Body mass index (BMI),waist to hip ratio (WHR),systolic blood pressure (SBP),diastolic blood pressure (DBP),serum uric acid,urea nitrogen,creatinine,triglyceride,total cholesterol,low-density lipoprotein-cholesterol (LDL-C),high-density lipoprotein-cholesterol (HDL-C),fasting plasma glucose (FPG),postprandial plasma glucose (PPG) were detected.RESULTS:We found patients with different Trp64Arg genotype showed significant differences in average uric acid concentrations (599.53±113.70 vs 529.78±81.10 vs 507.33±74.27,P<0.01) among CC,CT and TT genotype and there were significantly higher average uric acid concentrations in Trp64Arg TC + CC genotype individuals (557.95 ± 99.91 vs 503.47 ± 69.40 μ mol/L,P < 0.01) than those TT genotype subjects in the hyperuricemic group

  9. Dual single-scission event analysis of constitutive transferrin receptor (TfR) endocytosis and ligand-triggered β2-adrenergic receptor (β2AR) or Mu-opioid receptor (MOR) endocytosis.

    Science.gov (United States)

    Lampe, Marko; Pierre, Fabienne; Al-Sabah, Suleiman; Krasel, Cornelius; Merrifield, Christien J

    2014-10-01

    The dynamic relationship between constitutive and ligand-triggered clathrin-mediated endocytosis is only poorly characterized, and it remains controversial whether clathrin-coated pits specialize to internalize particular receptor cargo. Here we analyzed the ligand-triggered endocytosis of the model G-protein-coupled receptors (GPCRs) β2-adrenergic receptor (β2AR) and Mu-opioid receptor (MOR) at the level of individual endocytic events using a total internal reflection fluorescence microscopy (TIRFM)-based assay. Similar to the constitutive endocytosis of transferrin receptor (TfR), ligand- triggered endocytosis of β2AR occurs via quantized scission events hosted by clathrin spots and plaques of variable size and persistence. To address whether clathrin-coated structures (CCSs) specialize to internalize particular GPCRs, we adapted the TIRFM imaging assay to simultaneously quantify the internalization of TfR and the ligand- triggered endocytosis of the β2AR or MOR. Agonist-triggered β2AR or MOR endocytosis extended the maturation time of CCSs, as shown previously, but did not affect the rate of constitutive TfR endocytosis or loading of TfR into individual endocytic vesicles. Both the β2AR and the MOR receptors entered cells in the same vesicles as TfR, and the overall evidence for CCS specialization was weak. These data support a simple model in which different cargoes internalize through common CCSs.

  10. Yohimbine protects against endotoxin-induced acute lung injury by blockade of alpha 2A adrenergic receptor in rats

    Institute of Scientific and Technical Information of China (English)

    LIN Ying; ZHU Xi; YAO Wan-zhen; YANG Yah-lin; A La-ta; CHEN Li

    2011-01-01

    Background Alpha 2A adrenergic receptor (AR) is a subtype of α2 AR belonging to G protein-coupled receptors,and exerts a variety of biological effects. Recent studies have demonstrated that the α2A AR activation was closely related with inflammatory reaction. The present study aimed to investigate the influence of α2A AR antagonist,yohimbine,on the severity of endotoxin-induced acute lung injury in rats.Methods A total of 72 male Sprague-Dawley rats were randomly divided into three groups:control group,lipopolysaccharide (LPS) group and LPS + yohimbine group. Rats were intratracheally administrated with normal saline or LPS (300 μg),and the rats in the LPS + yohimbine group were treated with additional yohimbine (2 mg/kg,i.p) soon after LPS administration. Six,24 and 48 hours after treatment,arterial blood gas analysis was carried out,and optical microscopy was performed to evaluate pathological changes in the lung,and lung injury score was assessed. The count of white blood cells in bronchoalveolar lavage fluid (BALF) was determined. The levels of norepinephrine,tumor necrosis factor (TNF)-α,interleukin (IL)-1β and IL-6 in BALF were measured with enzyme-linked immunosorbent assay.Immunocytochemistry was performed for the detection of α2AAR on inflammatory cells in BALF.Results When compared with the control group,the oxygenation index in the LPS group was significantly decreased,and white blood cell count,the lung histopathological scores,levels of norepinephrine and IL-6 as well as α2A AR expression on inflammatory cells in the BALF were dramatically increased at different time points,and the concentrations of TNF-α and IL-1β were also increased except at 48 hours after LPS administration. The oxygenation index decreased while white blood cell count in BALF and the lung histopathological scores were obviously increased in the LPS +yohimbine group. The level of norepinephrine in BALF was increased at each time interval in the LPS + yohimbine group,and so

  11. Activation of alpha2-adrenergic receptors blunts epinephrine-induced lipolysis in subcutaneous adipose tissue during a hyperinsulinemic euglycemic clamp in men.

    Science.gov (United States)

    Stich, Vladimir; Pelikanova, Tereza; Wohl, Petr; Sengenès, Coralie; Zakaroff-Girard, Alexia; Lafontan, Max; Berlan, Michel

    2003-09-01

    The aim of this study was to investigate whether hyperinsulinemia modifies adrenergic control of lipolysis, with particular attention paid to the involvement of antilipolytic alpha2-adrenergic receptors (AR). Eight healthy male subjects (age: 23.9 +/- 0.9 yr; body mass index: 23.8 +/- 1.9) were investigated during a 6-h euglycemichyperinsulinemic clamp and in control conditions. Before and during the clamp, the effect of graded perfusions of isoproterenol (0.1 and 1 microM) or epinephrine (1 and 10 microM) on the extracellular glycerol concentration in subcutaneous abdominal adipose tissue was evaluated by using the microdialysis method. Both isoproterenol and epinephrine induced a dose-dependent increase in extracellular glycerol concentration when infused for 60 min through the microdialysis probes before and during hours 3 and 6 of the clamp. The catecholamine-induced increase was significantly lower during the clamp than before it, with the inhibition being more pronounced in hour 6 of the clamp. Isoproterenol (1 microM)-induced lipolysis was reduced by 28 and 44% during hours 3 and 6 of the clamp, respectively, whereas the reduction of epinephrine (100 microM)-induced lipolysis was significantly greater (by 63 and 70%, P < 0.01 and P < 0.04, respectively) during the same time intervals. When epinephrine was infused in combination with 100 microM phentolamine (a nonselective alpha-AR antagonist), the inhibition of epinephrine (10 microM)-induced lipolysis was only of 19 and 40% during hours 3 and 6 of the clamp, respectively. The results demonstrate that, in situ, insulin counteracts the epinephrine-induced lipolysis in adipose tissue. The effect involves 1) reduction of lipolysis stimulation mediated by the beta-adrenergic pathway and 2) the antilipolytic component of epinephrine action mediated by alpha2-ARs.

  12. Methylphenidate amplifies long-term potentiation in rat hippocampus CA1 area involving the insertion of AMPA receptors by activation of β-adrenergic and D1/D5 receptors.

    Science.gov (United States)

    Rozas, C; Carvallo, C; Contreras, D; Carreño, M; Ugarte, G; Delgado, R; Zeise, M L; Morales, B

    2015-12-01

    Methylphenidate (MPH, Ritalin©) is widely used in the treatment of Attention Deficit Hyperactivity Disorder and recently as a drug of abuse. Although the effect of MPH has been studied in brain regions such as striatum and prefrontal cortex (PFC), the hippocampus has received relatively little attention. It is known that MPH increases the TBS-dependent Long Term Potentiation (LTP) in the CA1 area. However, the cellular and molecular mechanisms involved in this process are still unknown. Using field potential recordings and western blot analysis in rat hippocampal slices of young rats, we found that acute application of MPH enhances LTP in CA3-CA1 synapses in a dose-dependent manner with an EC50 of 73.44±6.32 nM. Using specific antagonists and paired-pulse facilitation protocols, we observed that the MPH-dependent increase of LTP involves not only β-adrenergic receptors activation but also post-synaptic D1/D5 dopamine receptors. The inhibition of PKA with PKI, suppressed the facilitation of LTP induced by MPH consistent with an involvement of the adenyl cyclase-cAMP-PKA dependent cascade downstream of the activation of D1/D5 receptors. In addition, samples of CA1 areas taken from slices potentiated with MPH presented an increase in the phosphorylation of the Ser845 residue of the GluA1 subunit of AMPA receptors compared to control slices. This effect was reverted by SCH23390, antagonist of D1/D5 receptors, and PKI. Moreover, we found an increase of surface-associated functional AMPA receptors. We propose that MPH increases TBS-dependent LTP in CA3-CA1 synapses through a polysynaptic mechanism involving activation of β-adrenergic and D1/D5 dopaminergic receptors and promoting the trafficking and insertion of functional AMPA receptors to the plasma membrane.

  13. Relationship between oxidative stress and beta-2 adrenergic receptor desensitization%氧化应激与β2肾上腺素能受体脱敏的关系

    Institute of Scientific and Technical Information of China (English)

    任丽君; 刘华; 倪松石

    2012-01-01

    Oxidative stress is caused by an imbalance between the production of reactive oxygen species,reactive nitrogen species and removal,resulting in a high level of reactive oxygen species within an organism.This high level will damage molecular,cellular and organism.The currently studies have shown that oxidative stress plays an important role in β2-adrenergic receptor desensitization.However,β2-adrenergic receptor agonists have been largely restricted in the treatment of bronchial asthma because of β2-adrenergic receptor desensitization.The review is about oxidative stress and β2-adrenergic receptor.%氧化应激是体内活性氧和活性氮自由基产生过多,超过了机体清除速率,氧化系统和抗氧化系统失衡,导致活性氧在体内蓄积而引起的分子、细胞和机体的损伤.目前诸多研究认为氧化应激在β2肾上腺素能受体(β2-adrenergic receptor,β2AR)脱敏中起着重要作用,而β2AR脱敏会影响到β2肾上腺素能受体激动剂在支气管哮喘治疗中的效果,现就氧化应激与β2AR脱敏的关系作一综述.

  14. 乌龙茶减肥适宜剂量选择及对β3-肾上腺素能受体基因表达的影响%Dose selection and effect of Oolong tea on the expression of β3-adrenergic receptor gene for weight reducing

    Institute of Scientific and Technical Information of China (English)

    莫宝庆; 陈荣华; 郭锡熔

    2005-01-01

    .05).[3]脂肪细胞的最大径:乌龙茶低、中、高剂量组大鼠腹膜后、附睾周、肩胛间脂肪细胞的最大径明显低于肥胖对照组[(113±24),(86±29),(90±23),(120±30)μm;(94±20),(80±18),(64±17),(111±21)μm;(24±11),(21±11),(22±10),(27±11)μm,P<0.05].[4]脂肪组织中β3-肾上腺素能受体mRNA检测:乌龙茶中、高剂量组大鼠腹膜后、附睾周、肩胛间显著高于肥胖对照组和低剂量组[腹膜后:(0.72±0.11,0.64±0.112,0.40±0.08,0.34±0.10);附睾周:(1.06±0.21,1.02±0.24,0.42±0.13,0.43±0.11);肩胛间(1.01±0.42,0.70±0.17,0.42±0.10,0.49±0.16),P<0.01].结论:乌龙茶具有一定的减肥作用,与其增加脂肪组织中β3-肾上腺素能受体mRNA水平有关,中剂量(1.2g/kg)可能为一适宜剂量.该结果有助于对饮茶减肥理论的支持及有效剂量的选择.%BACKGROUND:Obesity is an important problem concerned domestically and internationally. How to control the body mass and to reduce the weight without any effect on normal food intake is the focus for study.OBJECTIVE:To probe into the weight-reducing effect of Oolong tea and its effect on the mRNA level of β3-adrenergic receptor(β3-AR).DESIGN: Completely randomized grouping, controlled trial SETTING:Department of Nutrition and Food Hygiene, College of Public Health, Nanjing Medical University; Institute of Pediatric Medicine, Nanjing Medical University.MATERIALS: This experiment was conducted in the laboratory of Nanjing Medical University from September 2003 to February 2004. The obese rat models were made with the diet of high energy and high fat in male rats weighing about 80 g. Thirty-two male obese rats were selected.And Oolong tea extract was prepared, whose concentration was equivalent to 0.24 g of tea.INTERVENTIONS:Thirty-two male obese rats were divided randomly in-to 4 groups: obese control group, low, middle and high dose of oolong tea groups. There were 8 rats in each group. The rats in the control group were fed by

  15. Loss of bone marrow adrenergic beta 1 and 2 receptors modifies transcriptional networks, reduces circulating inflammatory factors, and regulates blood pressure.

    Science.gov (United States)

    Ahmari, Niousha; Schmidt, Jordan T; Krane, Gregory A; Malphurs, Wendi; Cunningham, Bruce E; Owen, Jennifer L; Martyniuk, Christopher J; Zubcevic, Jasenka

    2016-07-01

    Hypertension (HTN) is a prevalent condition with complex etiology and pathophysiology. Evidence exists of significant communication between the nervous system and the immune system (IS), and there appears to be a direct role for inflammatory bone marrow (BM) cells in the pathophysiology of hypertension. However, the molecular and neural mechanisms underlying this interaction have not been characterized. Here, we transplanted whole BM cells from the beta 1 and 2 adrenergic receptor (AdrB1(tm1Bkk)AdrB2(tm1Bkk)/J) knockout (KO) mice into near lethally irradiated C57BL/6J mice to generate a BM AdrB1.B2 KO chimera. This allowed us to evaluate the role of the BM beta 1 and beta 2 adrenergic receptors in mediating BM IS homeostasis and regulating blood pressure (BP) in an otherwise intact physiological setting. Fluorescence-activated cell sorting demonstrated that a decrease in systolic and mean BP in the AdrB1.B2 KO chimera is associated with a decrease in circulating inflammatory T cells, macrophage/monocytes, and neutrophils. Transcriptomics in the BM identified 7,419 differentially expressed transcripts between the C57 and AdrB1.B2 KO chimera. Pathway analysis revealed differentially expressed transcripts related to several cell processes in the BM of C57 compared with AdrB1.B2 KO chimera, including processes related to immunity (e.g., T-cell activation, T-cell recruitment, cytokine production, leukocyte migration and function), the cardiovascular system (e.g., blood vessel development, peripheral nerve blood flow), and the brain (e.g., central nervous system development, neurite development) among others. This study generates new insight into the molecular events that underlie the interaction between the sympathetic drive and IS in modulation of BP.

  16. Neuroprotection by α2-Adrenergic Receptor Stimulation after Excitotoxic Retinal Injury: A Study of the Total Population of Retinal Ganglion Cells and Their Distribution in the Chicken Retina

    Science.gov (United States)

    Galindo-Romero, Caridad; Harun-Or-Rashid, Mohammad; Jiménez-López, Manuel; Vidal-Sanz, Manuel; Agudo-Barriuso, Marta

    2016-01-01

    We have studied the effect of α2-adrenergic receptor stimulation on the total excitotoxically injured chicken retinal ganglion cell population. N-methyl-D-aspartate (NMDA) was intraocularly injected at embryonic day 18 and Brn3a positive retinal ganglion cells (Brn3a+ RGCs) were counted in flat-mounted retinas using automated routines. The number and distribution of the Brn3a+ RGCs were analyzed in series of normal retinas from embryonic day 8 to post-hatch day 11 retinas and in retinas 7 or 14 days post NMDA lesion. The total number of Brn3a+ RGCs in the post-hatch retina was approximately 1.9x106 with a density of approximately 9.2x103 cells/mm2. The isodensity maps of normal retina showed that the density decreased with age as the retinal size increased. In contrast to previous studies, we did not find any specific region with increased RGC density, rather the Brn3a+ RGCs were homogeneously distributed over the central retina with decreasing density in the periphery and in the region of the pecten oculli. Injection of 5–10 μg NMDA caused 30–50% loss of Brn3a+ cells and the loss was more severe in the dorsal than in the ventral retina. Pretreatment with brimonidine reduced the loss of Brn3a+ cells both 7 and 14 days post lesion and the protective effect was higher in the dorsal than in the ventral retina. We conclude that α2-adrenergic receptor stimulation reduced the impact of the excitotoxic injury in chicken similarly to what has been shown in mammals. Furthermore, the data show that the RGCs are evenly distributed over in the retina, which challenges previous results that indicate the presence of specific high RGC-density regions of the chicken retina. PMID:27611432

  17. 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).

  18. Early postnatal maternal separation causes alterations in the expression of β3-adrenergic receptor in rat adipose tissue suggesting long-term influence on obesity

    Energy Technology Data Exchange (ETDEWEB)

    Miki, Takanori, E-mail: mikit@med.kagawa-u.ac.jp [Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University (Japan); Liu, Jun-Qian; Ohta, Ken-ichi; Suzuki, Shingo [Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University (Japan); Kusaka, Takashi [Department of Pediatrics, Faculty of Medicine, Kagawa University (Japan); Warita, Katsuhiko [Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University (Japan); Yokoyama, Toshifumi [Department of Bioresource and Agrobiosciences, Graduate School of Science and Technology, Kobe University (Japan); Jamal, Mostofa [Department of Forensic Medicine, Faculty of Medicine, Kagawa University (Japan); Ueki, Masaaki [Department of Anesthesia, Nishiwaki Municipal Hospital (Japan); Yakura, Tomiko; Tamai, Motoki [Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University (Japan); Sumitani, Kazunori [Department of Medical Education, Faculty of Medicine, Kagawa University (Japan); Hosomi, Naohisa [Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical Sciences (Japan); Takeuchi, Yoshiki [Department of Anatomy and Neurobiology, Faculty of Medicine, Kagawa University (Japan)

    2013-12-06

    Highlights: •High-fat diet intake following maternal separation did not cause body weight gain. •However, levels of metabolism-related molecules in adipose tissue were altered. •Increased levels of prohibitin mRNA in white fat were observed. •Attenuated levels of β3-adrenergic receptor mRNA were observed in brown fat. •Such alterations in adipose tissue may contribute to obesity later in life. -- Abstract: The effects of early postnatal maternal deprivation on the biological characteristics of the adipose tissue later in life were investigated in the present study. Sprague–Dawley rats were classified as either maternal deprivation (MD) or mother-reared control (MRC) groups. MD was achieved by separating the rat pups from their mothers for 3 h each day during the 10–15 postnatal days. mRNA levels of mitochondrial uncoupling protein 1 (UCP-1), β3-adrenergic receptor (β3-AR), and prohibitin (PHB) in the brown and white adipose tissue were determined using real-time RT-PCR analysis. UCP-1, which is mediated through β3-AR, is closely involved in the energy metabolism and expenditure. PHB is highly expressed in the proliferating tissues/cells. At 10 weeks of age, the body weight of the MRC and MD rats was similar. However, the levels of the key molecules in the adipose tissue were substantially altered. There was a significant increase in the expression of PHB mRNA in the white adipose tissue, while the β3-AR mRNA expression decreased significantly, and the UCP-1 mRNA expression remained unchanged in the brown adipose tissue. Given that these molecules influence the mitochondrial metabolism, our study indicates that early postnatal maternal deprivation can influence the fate of adipose tissue proliferation, presumably leading to obesity later in life.

  19. The QseC adrenergic signaling cascade in Enterohemorrhagic E. coli (EHEC.

    Directory of Open Access Journals (Sweden)

    David T Hughes

    2009-08-01

    Full Text Available The ability to respond to stress is at the core of an organism's survival. The hormones epinephrine and norepinephrine play a central role in stress responses in mammals, which require the synchronized interaction of the whole neuroendocrine system. Mammalian adrenergic receptors are G-coupled protein receptors (GPCRs; bacteria, however, sense these hormones through histidine sensor kinases (HKs. HKs autophosphorylate in response to signals and transfer this phosphate to response regulators (RRs. Two bacterial adrenergic receptors have been identified in EHEC, QseC and QseE, with QseE being downstream of QseC in this signaling cascade. Here we mapped the QseC signaling cascade in the deadly pathogen enterohemorrhagic E. coli (EHEC, which exploits this signaling system to promote disease. Through QseC, EHEC activates expression of metabolic, virulence and stress response genes, synchronizing the cell response to these stress hormones. Coordination of these responses is achieved by QseC phosphorylating three of the thirty-two EHEC RRs. The QseB RR, which is QseC's cognate RR, activates the flagella regulon which controls bacteria motility and chemotaxis. The QseF RR, which is also phosphorylated by the QseE adrenergic sensor, coordinates expression of virulence genes involved in formation of lesions in the intestinal epithelia by EHEC, and the bacterial SOS stress response. The third RR, KdpE, controls potassium uptake, osmolarity, and also the formation of lesions in the intestine. Adrenergic regulation of bacterial gene expression shares several parallels with mammalian adrenergic signaling having profound effects in the whole organism. Understanding adrenergic regulation of a bacterial cell is a powerful approach for studying the underlying mechanisms of stress and cellular survival.

  20. Preliminary evidence for a role of the adrenergic nervous system in generalized anxiety disorder

    Science.gov (United States)

    Zhang, Xiaobin; Norton, Joanna; Carrière, Isabelle; Ritchie, Karen; Chaudieu, Isabelle; Ryan, Joanne; Ancelin, Marie-Laure

    2017-01-01

    Generalized anxiety disorder (GAD) is a common chronic condition that is understudied compared to other psychiatric disorders. An altered adrenergic function has been reported in GAD, however direct evidence for genetic susceptibility is missing. This study evaluated the associations of gene variants in adrenergic receptors (ADRs) with GAD, with the involvement of stressful events. Data were obtained from 844 French community-dwelling elderly aged 65 or over. Anxiety disorders were assessed using the Mini-International Neuropsychiatry Interview, according to DSM-IV criteria. Eight single-nucleotide polymorphisms (SNPs) involved with adrenergic function were genotyped; adrenergic receptors alpha(1A) (ADRA1A), alpha(2A) (ADRA2A), and beta2 (ADRB2) and transcription factor TCF7L2. Questionnaires evaluated recent stressful life events as well as early environment during childhood and adolescence. Using multivariate logistic regression analyses four SNPs were significantly associated with GAD. A 4-fold modified risk was found with ADRA1A rs17426222 and rs573514, and ADRB2 rs1042713 which remained significant after Bonferroni correction. Certain variants may moderate the effect of adverse life events on the risk of GAD. Replication in larger samples is needed due to the small case number. This is the first study showing that ADR variants are susceptibility factors for GAD, further highlighting the critical role of the adrenergic nervous system in this disorder. PMID:28198454

  1. Preliminary evidence for a role of the adrenergic nervous system in generalized anxiety disorder.

    Science.gov (United States)

    Zhang, Xiaobin; Norton, Joanna; Carrière, Isabelle; Ritchie, Karen; Chaudieu, Isabelle; Ryan, Joanne; Ancelin, Marie-Laure

    2017-02-15

    Generalized anxiety disorder (GAD) is a common chronic condition that is understudied compared to other psychiatric disorders. An altered adrenergic function has been reported in GAD, however direct evidence for genetic susceptibility is missing. This study evaluated the associations of gene variants in adrenergic receptors (ADRs) with GAD, with the involvement of stressful events. Data were obtained from 844 French community-dwelling elderly aged 65 or over. Anxiety disorders were assessed using the Mini-International Neuropsychiatry Interview, according to DSM-IV criteria. Eight single-nucleotide polymorphisms (SNPs) involved with adrenergic function were genotyped; adrenergic receptors alpha(1A) (ADRA1A), alpha(2A) (ADRA2A), and beta2 (ADRB2) and transcription factor TCF7L2. Questionnaires evaluated recent stressful life events as well as early environment during childhood and adolescence. Using multivariate logistic regression analyses four SNPs were significantly associated with GAD. A 4-fold modified risk was found with ADRA1A rs17426222 and rs573514, and ADRB2 rs1042713 which remained significant after Bonferroni correction. Certain variants may moderate the effect of adverse life events on the risk of GAD. Replication in larger samples is needed due to the small case number. This is the first study showing that ADR variants are susceptibility factors for GAD, further highlighting the critical role of the adrenergic nervous system in this disorder.

  2. Glycyrrhetic acid synergistically enhances β₂-adrenergic receptor-Gs signaling by changing the location of Gαs in lipid rafts.

    Directory of Open Access Journals (Sweden)

    Qian Shi

    Full Text Available Glycyrrhetic acid (GA exerts synergistic anti-asthmatic effects via a β₂-adrenergic receptor (β₂AR-mediated pathway. Cholesterol is an important component of the structure and function of lipid rafts, which play critical roles in the β₂AR-Gs-adenylate cyclase (AC-mediated signaling pathway. Owing to the structural similarities between GA and cholesterol, we investigated the possibility that GA enhances β₂AR signaling by altering cholesterol distribution. Azide-terminal GA (ATGA was synthesized and applied to human embryonic kidney 293 (HEK293 cells expressing fusion β₂AR, and the electron spin resonance (ESR technique was utilized. GA was determined to be localized predominantly on membrane and decreased their cholesterol contents. Thus, the fluidity of the hydrophobic region increased but not the polar surface of the cell membrane. The conformations of membrane proteins were also changed. GA further changed the localization of Gαs from lipid rafts to non-raft regions, resulting the binding of β₂AR and Gαs, as well as in reduced β₂AR internalization. Co-localization of β₂AR, Gαs, and AC increased isoproterenol-induced cAMP production and cholesterol reloading attenuated this effect. A speculation wherein GA enhances beta-adrenergic activity by increasing the functional linkage between the subcomponents of the membrane β₂AR-protein kinase A (PKA signaling pathway was proposed. The enhanced efficacy of β₂AR agonists by this novel mechanism could prevent tachyphylaxis.

  3. Renal albumin excretion: twin studies identify influences of heredity, environment, and adrenergic pathway polymorphism

    DEFF Research Database (Denmark)

    Rao, Fangwen; Wessel, Jennifer; Wen, Gen;

    2007-01-01

    Albumin excretion marks early glomerular injury in hypertension. This study investigated heritability of albumin excretion in twin pairs and its genetic determination by adrenergic pathway polymorphism. Genetic associations used single nucleotide polymorphisms at adrenergic pathway loci spanning...... biosynthesis (tyrosine hydroxylase), catabolism (monoamine oxidase A), storage/release (chromogranin A), receptor target (dopamine D1 receptor), and postreceptor signal transduction (sorting nexin 13 and rho kinase). Epistasis (gene-by-gene interaction) occurred between alleles at rho kinase, tyrosine...... hydroxylase, chromogranin A, and sorting nexin 13. Dopamine D1 receptor polymorphism showed pleiotropic effects on both albumin and dopamine excretion. These studies establish new roles for heredity and environment in albumin excretion. Urinary excretions of albumin and catecholamines are highly heritable...

  4. The Combination of Marketed Antagonists of α1b-Adrenergic and 5-HT2A Receptors Inhibits Behavioral Sensitization and Preference to Alcohol in Mice: A Promising Approach for the Treatment of Alcohol Dependence.

    Directory of Open Access Journals (Sweden)

    Fabrice Trovero

    Full Text Available Alcohol-dependence is a chronic disease with a dramatic and expensive social impact. Previous studies have indicated that the blockade of two monoaminergic receptors, α1b-adrenergic and 5-HT2A, could inhibit the development of behavioral sensitization to drugs of abuse, a hallmark of drug-seeking and drug-taking behaviors in rodents. Here, in order to develop a potential therapeutic treatment of alcohol dependence in humans, we have blocked these two monoaminergic receptors by a combination of antagonists already approved by Health Agencies. We show that the association of ifenprodil (1 mg/kg and cyproheptadine (1 mg/kg (α1-adrenergic and 5-HT2 receptor antagonists marketed as Vadilex ® and Periactine ® in France, respectively blocks behavioral sensitization to amphetamine in C57Bl6 mice and to alcohol in DBA2 mice. Moreover, this combination of antagonists inhibits alcohol intake in mice habituated to alcohol (10% v/v and reverses their alcohol preference. Finally, in order to verify that the effect of ifenprodil was not due to its anti-NMDA receptors property, we have shown that a combination of prazosin (0.5 mg/kg, an α1b-adrenergic antagonist, Mini-Press ® in France and cyproheptadine (1 mg/kg could also reverse alcohol preference. Altogether these findings strongly suggest that combined prazosin and cyproheptadine could be efficient as a therapy to treat alcoholism in humans. Finally, because α1b-adrenergic and 5-HT2A receptors blockade also inhibits behavioral sensitization to psychostimulants, opioids and tobacco, it cannot be excluded that this combination will exhibit some efficacy in the treatment of addiction to other abused drugs.

  5. Development of a multiplex non-radioactive receptor assay : the benzodiazepine receptor, the serotonin transporter and the beta-adrenergic receptor

    NARCIS (Netherlands)

    de Jong, Lutea A. A.; Jeronimus-Stratingh, C. Margot; Cremers, Thomas I. F. H.

    2007-01-01

    Binding assays still form a fundamental part of modem drug development. Receptor binding assays are mostly based on radioactivity because of their speed, ease of use and reproducibility. Disadvantages, such as health hazards and production of radioactive waste, have prompted the development of non-r

  6. Cooperative regulation of non-small cell lung carcinoma by nicotinic and beta-adrenergic receptors: a novel target for intervention.

    Directory of Open Access Journals (Sweden)

    Hussein A N Al-Wadei

    Full Text Available Lung cancer is the leading cause of cancer death; 80-85% of lung cancer cases are non-small cell lung cancer (NSCLC. Smoking is a documented risk factor for the development of this cancer. Although nicotine does not have the ability to initiate carcinogenic events, recent studies have implicated nicotine in growth stimulation of NSCLC. Using three NSCLC cell lines (NCI-H322, NCI-H441 and NCI-H1299, we identified the cooperation of nicotinic acetylcholine receptors (nAChRs and β-adrenergic receptors (β-ARs as principal regulators of these effects. Proliferation was measured by thymidine incorporation and MTT assays, and Western blots were used to monitor the upregulation of the nAChRs and activation of signaling molecules. Noradrenaline and GABA were measured by immunoassays. Nicotine-treated NSCLC cells showed significant induction of the α7nAChR and α4nAChR, along with significant inductions of p-CREB and p-ERK1/2 accompanied by increases in the stress neurotransmitter noradrenaline, which in turn led to the observed increase in DNA synthesis and cell proliferation. Effects on cell proliferation and signaling proteins were reversed by the α7nAChR antagonist α-BTX or the β-blocker propranolol. Nicotine treatment also down-regulated expression of the GABA synthesizing enzyme GAD 65 and the level of endogenous GABA, while treatment of NSCLC cells with GABA inhibited cell proliferation. Interestingly, GABA acts by reducing β-adrenergic activated cAMP signaling. Our findings suggest that nicotine-induced activation of this autocrine noradrenaline-initiated signaling cascade and concomitant deficiency in inhibitory GABA, similar to modulation of these neurotransmitters in the nicotine-addicted brain, may contribute to the development of NSCLC in smokers. Our data suggest that exposure to nicotine either by tobacco smoke or nicotine supplements facilitates growth and progression of NSCLC and that pharmacological intervention by β blocker may

  7. Influence of angiotensin converting enzyme gene insertion/deletion polymorphism and β3-adrenergic receptor gene Trp64Arg polymorphism on fetal growth and neonatal insulin sensitivity%血管紧张素转化酶基因插入/缺失多态性及β3肾上腺素能受体基因Trp64Arg多态性对胎儿宫内发育及新生儿胰岛素敏感性的影响

    Institute of Scientific and Technical Information of China (English)

    崔蕴璞; 韩彤妍; 王新利; 叶鸿瑁

    2008-01-01

    Objective To understand the influence of angiotensin converting enzyme(ACE)gene insertion/deletion(I/D)polymorphism and β3-adrenergic receptor(β3-AR)gene Trp64Arg polymorphism on fetal growth and neonatal insulin sensitivity.Methods Totally 296 newborn infants were selected into our study and divided into 2 groups according to gestational age and birth weight:adequate-for-gestationalage(AGA)group(222 cases)and small-for-gestational-age(SGA)group(74 case).Serum glucose and insulin were examined in the morning of the 3rd day before milk.Insulin sensitivity was evaluated by homeostasis model assessment(HOMA)equation.β3-AR gene Trp64Arg polymorphism and ACE gene I/D polymorphism(202 cases)were analysed using polymerase chain reaction-restricted fragment length polymorphism(PCR-RFLP)technique.Gestational age,birth weight,birth weight percentage,serum glucose,insulin and HOMA-IR were compared among different genotype groups.Statistical analysis was performed with the SPSS 10.0 software.Results No significant difference was found between the sernm glucose level of SGA group(4.03±1.05 mmol/L)and AGA group(4.05±1.14 mmol/L),P=0.008. The serum insulin level(converted into Ln)of SGA group(2.262±0.746)was significantly higher than that of AGA group(1.757±0.805),P<0.001.The HOMA-IR(also convened into Ln)level of SGA group(0.217±0.367)was also significantly higher than that of AGA group(0.001±0.378),P<0.001. In the SGA group β3-AR gene Arg64 allele carriers had higher serum insulin and HOMA-IR level(botll changed to Ln,2.654±0.701,0.371±0.338)compared with noncarriers(2.074±0.698,0.143± O.360),P<0.05.The ACE gene DD genotype carriers had higher serum insulin and HOMA-IR level(both were converted into Ln,2.19 4-0.91,0.5l 4-1.01)compared with II(1.77 ±0.85,0.02 ±0.93) and ID genotype group(1.77 ±0.83,0.05 ±0.91),P<0.05.The ACE gene DD carriers had lower birth weight percentage compared with II and ID genotype group.P<0.05.When both genes'polymorphisms were taken

  8. β3肾上腺素能受体基因Trp64Arg多态性与蒙古族原发性高血压病相关性分析%Association of Beta 3 Adrenergic Receptor Gene Polymorphism and Essential Hypertension in Mongolian Population

    Institute of Scientific and Technical Information of China (English)

    张晓云; 魏芳婧; 徐力; 阴淑莹

    2012-01-01

    目的 检测蒙古族原发性高血压人群中β3肾上腺素能受体基因Trp64Arg多态性,探讨其与蒙古族人群原发性高血压病(EH)和其他心血管病危险因素的关系.方法 应用PCR技术检测原发性高血压病患者102例,健康体检者93例.比较两组Trp64Arg突变基因型和临床特征.结果 高血压病组与对照组β3-AR基因突变频率两者差异无统计学意义(P>0.05),基因Tr p 64Arg突变者的体质量指数显著高于正常基因型(P0. 05). In the patients group,body mass index(BMI)in patients with gene Trp64Arg mutation were significantly higher than that in patients with normal genotype(P<0. 05). Triglycerides,glucose,insulin,uric acid were significantly different between the two groups(P<0. 05). Conclusion Trp64Arg mutation may not be the determinants of the occurrence of hypertension. However, the gene mutation may be related to obesity,lipid metabolism,glucose metabolism and other risk factors.

  9. The variation and adaptive evolution analysis on theβ3-adrenergic receptor gene(ADRB3) of plateau sheep%高原绵羊β3-肾上腺素受体基因(ADRB3)变异与适应性进化分析

    Institute of Scientific and Technical Information of China (English)

    安清明; 刘秀; 王继卿; 李少斌; 胡江; 罗玉柱

    2015-01-01

    为了探讨ADRB3基因变异及其与高原绵羊适应性进化关系,研究以‘甘肃高山细毛羊’‘藏绵羊’及‘滩羊’3个绵羊品种为观测对象,采用PCR-SSCP方法检测ADRB3基因部分内含子序列的遗传多态性,同时基于DA遗传距离用NJ 法进行系统聚类分析,明确3个绵羊品种与不同物种群体间的遗传进化关系.结果表明:3个绵羊品种共检测到5种等位基因(A,B,C,D和 E),构成了7种基因型(AA,AD,BD,BE,CC,CD和 DD),存在6个突变位点(T/C,C/T,A/G/C,T/C,A/C和T/C),‘滩羊’中未检测到等位基因 A和基因型 AA与 AD,优势等位基因与基因型在不同群体间各不相同;聚类结果显示,不同物种总体上分为2大类,其中绵羊、山羊和家牛等聚为一支,且‘藏绵羊’与‘甘肃高山细毛羊’之间的遗传距离最小,‘滩羊’次之;而大猩猩、人和小家鼠聚为一支.研究发现, ADRB3基因在3个绵羊群体中存在丰富的多态性,且存在群体间差异.ADRB3基因多态性丰富的绵羊品种在高海拔地区适应性能力较强,ADRB3基因可能在绵羊适应性进化中具有一定功能.%To study the variations of ADRB3 gene and its relationship with adaptive evolution of plat-eau sheep,the genetic polymorphhism of part of intron of ADRB3 gene in 3 plateau sheep breed(Gansu Al-pine Merino,Tibetan Sheep and Tan Sheep)were detected by PCR-SSCP,NJ tree were constructed by ge-netic distance (DA)to define the genetic relationship between three sheep and different species groups.The results showed that 6 SNPs (T/C,C/T,A/G/C,T/C,A/C and T/C)corresponding to 5 alleles (A,B,C,D and E)and performing 7 kinds of genotypes (AA,AD,BD,BE,CC,CD and DD)were detected in the intron of ADRB3 gene in 3 plateau sheep breed.The allele D with the frequency of 0.415 9 and genotype CD with the frequency of 0.254 0 were both the highest,and allele A and genotype AA/AD were not detected in Tan sheep.Clustering results showed that different

  10. Expression and localization of the AT1 and AT2 angiotensin II receptors and α1A and α1D adrenergic receptors in aorta of hypertensive and diabetic rats.

    Science.gov (United States)

    Rodríguez, Jessica Edith; Romero-Nava, Rodrigo; Reséndiz-Albor, Aldo Arturo; Rosales-Cruz, Erika; Hong, Enrique; Huang, Fengyang; Villafaña, Santiago

    2017-01-01

    Hypertension and diabetes are multifactorial diseases that frequently coexist and exacerbate each another. During the development of diabetes, the impairment of noradrenergic and renin-angiotensin systems has been reported in the response mediated by α1-AR and AT1 receptors. Although their participation in the development of cardiovascular complications is still controversial, some studies have found increased or diminished response to the vasoconstrictive effect of noradrenaline or angiotensin II in a time-dependent manner of diabetes. Thus, the aim of this work was to investigate the possible changes in the expression or localization of α1-AR (α1A and α1D) and angiotensin II receptors (AT1 and AT2) in aorta of rats after 4 weeks of the onset of diabetes. In order to be able to examine the expression of these receptors, immunofluorescence procedure was performed in tunica intima and tunica media of histological sections of aorta. Fluorescence was detected by a confocal microscopy. Our results showed that the receptors are expressed in both tunics, where adrenergic receptors have a higher density in tunica intima and tunica media of SHR compared with WKY; meanwhile, the expression of angiotensin II receptors is not modified in both groups of rats. On the other hand, the results showed that diabetes produced an increase or a decrease in the expression of receptors that is not associated to a specific type of receptor, vascular region, or strain of rat. In conclusion, diabetes and hypertension modify the expression of the receptors in tunica intima and tunica media of aorta in a different way.

  11. Prediction of blood-brain barrier permeation of α-adrenergic and imidazoline receptor ligands using PAMPA technique and quantitative-structure permeability relationship analysis.

    Science.gov (United States)

    Vucicevic, Jelica; Nikolic, Katarina; Dobričić, Vladimir; Agbaba, Danica

    2015-02-20

    Imidazoline receptor ligands are a numerous family of biologically active compounds known to produce central hypotensive effect by interaction with both α2-adrenoreceptors (α2-AR) and imidazoline receptors (IRs). Recent hypotheses connect those ligands with several neurological disorders. Therefore some IRs ligands are examined as novel centrally acting antihypertensives and drug candidates for treatment of various neurological diseases. Effective Blood-Brain Barrier (BBB) permeability (P(e)) of 18 IRs/α-ARs ligands and 22 Central Nervous System (CNS) drugs was experimentally determined using Parallel Artificial Membrane Permeability Assay (PAMPA) and studied by the Quantitative-Structure-Permeability Relationship (QSPR) methodology. The dominant molecules/cations species of compounds have been calculated at pH = 7.4. The analyzed ligands were optimized using Density Functional Theory (B3LYP/6-31G(d,p)) included in ChemBio3D Ultra 13.0 program and molecule descriptors for optimized compounds were calculated using ChemBio3D Ultra 13.0, Dragon 6.0 and ADMET predictor 6.5 software. Effective permeability of compounds was used as dependent variable (Y), while calculated molecular parametres were used as independent variables (X) in the QSPR study. SIMCA P+ 12.0 was used for Partial Least Square (PLS) analysis, while the stepwise Multiple Linear Regression (MLR) and Artificial Neural Networks (ANN) modeling were performed using STASTICA Neural Networks 4.0. Predictive potential of the formed models was confirmed by Leave-One-Out Cross- and external-validation and the most reliable models were selected. The descriptors that are important for model building are identified as well as their influence on BBB permeability. Results of the QSPR studies could be used as time and cost efficient screening tools for evaluation of BBB permeation of novel α-adrenergic/imidazoline receptor ligands, as promising drug candidates for treatment of hypertension or neurological diseases.

  12. FGF receptor genes and breast cancer susceptibility

    DEFF Research Database (Denmark)

    Agarwal, D; Pineda, S; Michailidou, K

    2014-01-01

    Background:Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying...... was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2.Conclusion:Our results suggest...

  13. Affinity chromatography of alpha/sub 2/-adrenergic receptors (. cap alpha. /sub 2/AR) from pig cerebral cortex

    Energy Technology Data Exchange (ETDEWEB)

    Repaske, M.G.; Limbird, L.E.

    1986-03-01

    A high capacity, ..cap alpha../sub 2/AR-selective affinity resin (YOH. ag) has been prepared by coupling yohimbinic acid to diaminodipropylamine agarose with 1,3 dicyclohexylcarbodiimide. Unreacted amino groups on the agarose matrix are blocked subsequently by acetylation. One volume of YOH. ag adsorbs 75% of the ..cap alpha../sub 2/AR from 50 volumes of digitonin-solubilized preparation containing 0.2 pmol ..cap alpha../sub 2/AR/mg protein. Digitonin-solubilized preparations are derived from cholate extracts of porcine cerebral cortex containing approx. 0.075 pmol ..cap alpha../sub 2/AR/mg protein. Adsorption of ..cap alpha../sub 2/AR to YOH. ag is selective and thus is blocked by the ..cap alpha..-adrenergic antagonist phentolamine. Adsorbed ..cap alpha../sub 2/AR are eluted with 10 ..mu..M phentolamine (20% yield) after removal of non-related proteins with NaCl gradients. Following hydroxylapatite chromatography to concentrate ..cap alpha..''AR and to remove phentolamine, the ..cap alpha..AR is present at 200-400 pmol/mg protein, assayed using sub-saturating concentrations of (/sup 3/H)-yohimbine. (It is estimated that the specific activity of a homogeneous ..cap alpha../sub 2/AR preparation would be 12,000-16,000 pmol/mg protein.) The availability of large quantities of cortical ..cap alpha../sub 2/AR and a resin easily prepared from commercially-supplied reagents suggests that purification of quantities of ..cap alpha../sub 2/AR sufficient for subsequent biochemical studies is feasible.

  14. Differential regulation of human cardiac β-adrenergic and muscarinic receptors by chronic β-adrenoceptor antagonist treatment

    OpenAIRE

    Motomura, S.; Deighton, N M; Zerkowski, H.-R.; Khamssi, M.; Brodde, O.-E.

    1990-01-01

    In patients undergoing coronary artery bypass grafting chronic β1-adrenoceptor antagonist treatment increased right atrial β1-adrenoceptor number, did not affect β2-adrenoceptor number and decreased muscarinic M2-receptor number. Concomitantly, the M2-receptor-mediated negative inotropic effect of carbachol was reduced, while the β1-adrenoceptor-mediated positive inotropic effect of noradrenaline was not altered. The β2-adrenoceptor mediated positive inotropic effect of procaterol, however, w...

  15. Catechol-O-methlytransferase inhibition alters pain and anxiety-related volitional behaviors through activation of β-adrenergic receptors in the rat

    Science.gov (United States)

    Kline, R. H.; Exposto, F. G.; O’Buckley, S. C.; Westlund, K. N.; Nackley, A. G.

    2015-01-01

    Reduced catechol-O-methyltransferase (COMT) activity resulting from genetic variation or pharmacological depletion results in enhanced pain perception in humans and nociceptive behaviors in animals. Using phasic mechanical and thermal reflex tests (e.g. von Frey, Hargreaves), recent studies show that acute COMT-dependent pain in rats is mediated by β-adrenergic receptors (βARs). In order to more closely mimic the characteristics of human chronic pain conditions associated with prolonged reductions in COMT, the present study sought to determine volitional pain-related and anxiety-like behavioral responses following sustained as well as acute COMT inhibition using an operant 10–45°C thermal place preference task and a light/dark preference test. In addition, we sought to evaluate the effects of sustained COMT inhibition on generalized body pain by measuring tactile sensory thresholds of the abdominal region. Results demonstrated that acute and sustained administration of the COMT inhibitor OR486 increased pain behavior in response to thermal heat. Further, sustained administration of OR486 increased anxiety behavior in response to bright light, as well as abdominal mechanosensation. Finally, all pain-related behaviors were blocked by the non-selective βAR antagonist propranolol. Collectively, these findings provide the first evidence that stimulation of ARs following acute or chronic COMT inhibition drives cognitive-affective behaviors associated with heightened pain that affects multiple body sites. PMID:25659347

  16. Intracellular β2-adrenergic receptor signaling specificity in mouse skeletal muscle in response to single-dose β2-agonist clenbuterol treatment and acute exercise.

    Science.gov (United States)

    Sato, Shogo; Shirato, Ken; Mitsuhashi, Ryosuke; Inoue, Daisuke; Kizaki, Takako; Ohno, Hideki; Tachiyashiki, Kaoru; Imaizumi, Kazuhiko

    2013-05-01

    The aim of this study was to clarify the intracellular β2-adrenergic receptor signaling specificity in mouse slow-twitch soleus and fast-twitch tibialis anterior (TA) muscles, resulting from single-dose β2-agonist clenbuterol treatment and acute exercise. At 1, 4, and 24 h after single-dose treatment with clenbuterol or after acute running exercise, the soleus and TA muscles were isolated and subjected to analysis. The phosphorylation of p38 mitogen-activated protein kinase (MAPK) increased after single-dose clenbuterol treatment and acute exercise in the soleus muscle but not in the TA muscle. Although there was no change in the phosphorylation of Akt after acute exercise in either muscle, phosphorylation of Akt in the soleus muscle increased after single-dose clenbuterol treatment, whereas that in the TA muscle remained unchanged. These results suggest that p38 MAPK and Akt pathways play a functional role in the adaptation to clenbuterol treatment and exercise, particularly in slow-twitch muscles.

  17. The role ofα- andβ- adrenergic receptors in the spasmolytic effects on rat ileum ofPetroselinum crispumLatifolum (parsley)

    Institute of Scientific and Technical Information of China (English)

    N MirzaieDamabi; AA Moazedi; SM Seyyednejad

    2010-01-01

    Objective:To investigatePetroselinum crispumLatifolum (parsley) for treating stomach and intestinal disorders in Iran.Methods:An80% ethanol extract was prepared from parsley seeds, and its antispasmodic activity assessed by measuring contractions of isolated ilea induced by60 mM potassium chloride(KCl). A piece of ileum from an adult male Wistar rat was dissected and mounted in an organ bath containing Tyrode's solution, and ileum contractions were recorded by an isotonic transducer under one gram resting tension. The effect of parsley extract was measured in the presence of two antagonists’ of α- and β-adrenoceptors.Results: These experiments showed that parsley extract inhibited the response to 60 mMKCl in a concentration-dependent manner (P<0.01,n=7). The spasmolytic effect of parsley extract was unaffected by1 μM phentolamine or1 μM propranolol.Conclusions: This study shows that parsley seed extract is a relaxant of isolated rat ileum and the relaxation effect of extract does not involved adrenergic receptors.

  18. Effect of electrical stimulation on beta-adrenergic receptor population and cyclic amp production in chicken and rat skeletal muscle cell cultures

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.; Strietzel, C. J.

    2000-01-01

    Expression of the beta-adrenergic receptor (betaAR) and its coupling to cyclic AMP (cAMP) synthesis are important components of the signaling system that controls muscle atrophy and hypertrophy, and the goal of this study was to determine if electrical stimulation in a pattern simulating slow muscle contraction would alter the betaAR response in primary cultures of avian and mammalian skeletal muscle cells. Specifically, chicken skeletal muscle cells and rat skeletal muscle cells that had been grown for 7 d in culture were subjected to electrical stimulation for an additional 2 d at a pulse frequency of 0.5 pulses/sec and a pulse duration of 200 msec. In chicken skeletal muscle cells, the betaAR population was not significantly affected by electrical stimulation; however, the ability of these cells to synthesize cyclic AMP was reduced by approximately one-half. In contrast, the betaAR population in rat muscle cells was increased slightly but not significantly by electrical stimulation, and the ability of these cells to synthesize cyclic AMP was increased by almost twofold. The basal levels of intracellular cyclic AMP in neither rat muscle cells nor chicken muscle cells were affected by electrical stimulation.

  19. Catechol-O-methyltransferase inhibition alters pain and anxiety-related volitional behaviors through activation of β-adrenergic receptors in the rat.

    Science.gov (United States)

    Kline, R H; Exposto, F G; O'Buckley, S C; Westlund, K N; Nackley, A G

    2015-04-02

    Reduced catechol-O-methyltransferase (COMT) activity resulting from genetic variation or pharmacological depletion results in enhanced pain perception in humans and nociceptive behaviors in animals. Using phasic mechanical and thermal reflex tests (e.g. von Frey, Hargreaves), recent studies show that acute COMT-dependent pain in rats is mediated by β-adrenergic receptors (βARs). In order to more closely mimic the characteristics of human chronic pain conditions associated with prolonged reductions in COMT, the present study sought to determine volitional pain-related and anxiety-like behavioral responses following sustained as well as acute COMT inhibition using an operant 10-45°C thermal place preference task and a light/dark preference test. In addition, we sought to evaluate the effects of sustained COMT inhibition on generalized body pain by measuring tactile sensory thresholds of the abdominal region. Results demonstrated that acute and sustained administration of the COMT inhibitor OR486 increased pain behavior in response to thermal heat. Further, sustained administration of OR486 increased anxiety behavior in response to bright light, as well as abdominal mechanosensation. Finally, all pain-related behaviors were blocked by the non-selective βAR antagonist propranolol. Collectively, these findings provide the first evidence that stimulation of βARs following acute or chronic COMT inhibition drives cognitive-affective behaviors associated with heightened pain that affects multiple body sites.

  20. Partial least square and hierarchical clustering in ADMET modeling: prediction of blood-brain barrier permeation of α-adrenergic and imidazoline receptor ligands.

    Science.gov (United States)

    Nikolic, Katarina; Filipic, Slavica; Smoliński, Adam; Kaliszan, Roman; Agbaba, Danica

    2013-01-01

    PURPOSE. Rate of brain penetration (logPS), brain/plasma equilibration rate (logPS-brain), and extent of blood-brain barrier permeation (logBB) of 29 α-adrenergic and imidazoline-receptors ligands were examined in Quantitative-Structure-Property Relationship (QSPR) study. METHODS. Experimentally determined chromatographic retention data (logKw at pH 4.4, slope (S) at pH 4.4, logKw at pH 7.4, slope (S) at pH 7.4, logKw at pH 9.1, and slope (S) at pH 9.1) and capillary electrophoresis migration parameters (μeff at pH 4.4, μeff at pH 7.4, and μeff at pH 9.1), together with calculated molecular descriptors, were used as independent variables in the QSPR study by use of partial least square (PLS) methodology. RESULTS. Predictive potential of the formed QSPR models, QSPR(logPS), QSPR(logPS-brain), QSPR(logBB), was confirmed by cross- and external validation. Hydrophilicity (Hy) and H-indices (H7m) were selected as significant parameters negatively correlated with both logPS and logPS-brain, while topological polar surface area (TPSA(NO)) was chosen as molecular descriptor negatively correlated with both logPS and logBB. The principal component analysis (PCA) and hierarchical clustering analysis (HCA) were applied to cluster examined drugs based on their chromatographic, electrophoretic and molecular properties. Significant positive correlations were obtained between the slope (S) at pH 7.4 and logBB in A/B cluster and between the logKw at pH 9.1 and logPS in C/D cluster. CONCLUSIONS. Results of the QSPR, clustering and correlation studies could be used as novel tool for evaluation of blood-brain barrier permeation of related α-adrenergic/imidazoline receptor ligands.This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.PURPOSE. Rate of brain penetration (logPS), brain/plasma equilibration rate (logPS-brain), and extent of blood-brain barrier permeation (logBB) of 29 α-adrenergic

  1. Effects of Electroacupuncture on Pain Threshold of Laboring Rats and the Expression of Norepinephrine Transporter and α2 Adrenergic Receptor in the Central Nervous System

    Directory of Open Access Journals (Sweden)

    Qianli Tang

    2016-01-01

    Full Text Available To observe the effects of electroacupuncture on pain threshold of laboring rats and the expression of norepinephrine transporter and α2 adrenergic receptor in the central nervous system to determine the mechanism of the analgesic effect of labor. 120 pregnant rats were divided into 6 groups: a control group, 4 electroacupuncture groups, and a meperidine group. After interventions, the warm water tail-flick test was used to observe pain threshold. NE levels in serum, NET, and α2AR mRNA and protein expression levels in the central nervous system were measured. No difference in pain threshold was observed between the 6 groups before intervention. After intervention, increased pain thresholds were observed in all groups except the control group with a higher threshold seen in the electroacupuncture groups. Serum NE levels decreased in the electroacupuncture and MP groups. Increases in NET and α2AR expression in the cerebral cortex and decreases in enlarged segments of the spinal cord were seen. Acupuncture increases uptake of NE via cerebral NET and decreases its uptake by spinal NET. The levels of α2AR are also increased and decreased, respectively, in both tissues. This results in a decrease in systemic NE levels and may be the mechanism for its analgesic effects.

  2. Osthole Improves Spatial Memory Deficits in Rats via Hippocampal α1-Adrenergic and D1/D2 Receptors

    Directory of Open Access Journals (Sweden)

    Li-Wei Lin

    2013-01-01

    Full Text Available The present study evaluated the effect of osthole, an active ingredient isolated from Cnidium monnieri L. Cusson, on spatial memory deficits caused by central neurotoxins using the Morris water maze in rats. The involvement of catecholaminergic receptors on the memory-enhancing effect of osthole in rat hippocampus was further investigated by intrahippocampal injection of catecholaminergic receptor antagonists. Intracisternal injection of osthole (10 μg/brain improved the spatial performance and working memory impairments caused by the catecholaminergic neurotoxin 6-hydroxydopamine. No significant differences in swimming speeds were observed among sham, neurotoxin-induced, and osthole-treated groups. Intracisternal osthole injection also attenuated the spatial performance and working memory impairments caused by the α1 receptor antagonist phenoxybenzamine, the D1 receptor antagonist SCH 23390, and the D2 receptor antagonist sulpiride. Therefore, we demonstrated that the effect of osthole on improving spatial memory deficits may be related to the activation of hippocampal α1 and D1/D2 receptors.

  3. Antibodies to the α1-adrenergic receptor cause vascular impairments in rat brain as demonstrated by magnetic resonance angiography.

    Directory of Open Access Journals (Sweden)

    Peter Karczewski

    Full Text Available BACKGROUND: Circulating agonistic autoantibodies acting at G protein-coupled receptors have been associated with numerous sever pathologies in humans. Antibodies directed predominantly against the α(1-adrenergig receptor were detected in patients suffering from widespread diseases such as hypertension and type 2 diabetes. Their deleterious action has been demonstrated for peripheral organs. We postulate that antibodies to the α(1-adrenergig receptor are relevant pathomolecules in diseases of the central nervous system associated with vascular impairments. METHODOLOGY/PRINCIPAL FINDINGS: Using a rat model we studied the long-term action of antibodies against the α(1-adrenergig receptor either induced by immunization with a receptor peptide or applied by intravenous injection. The vasculature in the rat brains was investigated by time-of-flight magnetic resonance angiography using a 9.4 Tesla small animal MR imaging system. Visual examination of maximum-intensity-projections (MIPs of brain angiographs revealed the development of vascular defects in antibody- exposed animals between three and eight months of treatment. Relative vascular areas were derived from representative MIP image sections by grayscale analysis and used to form an index of vascular circulation. Animals exposed to the action of α(1-adrenergig receptor antibodies showed significantly reduced vascular areas (p<0.05. Calculated index values indicated attenuated blood flow in both antibody-treated cohorts compared to their respective controls reaching with (relative units ± standard error, n = 10 0.839 ± 0.026 versus 0.919 ± 0.026 statistical significance (p<0.05 for peptide-immunized rats. CONCLUSION/SIGNIFICANCE: We present evidence that antibodies to the α(1-adrenergig receptor cause cerebrovascular impairments in the rat. Our findings suggest the pathological significance of these antibodies in pathologies of the human central nervous system linked to impairments of

  4. β-Adrenergic receptor antagonists inhibit vasculogenesis of embryonic stem cells by downregulation of nitric oxide generation and interference with VEGF signalling.

    Science.gov (United States)

    Sharifpanah, Fatemeh; Saliu, Fatjon; Bekhite, Mohamed M; Wartenberg, Maria; Sauer, Heinrich

    2014-11-01

    The β-adrenoceptor antagonist Propranolol has been successfully used to treat infantile hemangioma. However, its mechanism of action is so far unknown. The hypothesis of this research was that β-adrenoceptor antagonists may interfere with endothelial cell differentiation of stem cells. Specifically, the effects of the non-specific β-adrenergic receptor (β-adrenoceptor) antagonist Propranolol, the β1-adrenoceptor-specific antagonist Atenolol and the β2-adrenoceptor-specific antagonist ICI118,551 on vasculogenesis of mouse embryonic stem (ES) cells were investigated. All three β-blockers dose-dependently downregulated formation of capillary structures in ES cell-derived embryoid bodies and decreased the expression of the vascular cell markers CD31 and VE-cadherin. Furthermore, β-blockers downregulated the expression of fibroblast growth factor-2 (FGF-2), hypoxia inducible factor-1α (HIF-1α), vascular endothelial growth factor 165 (VEGF165), VEGF receptor 2 (VEGF-R2) and phospho VEGF-R2, as well as neuropilin 1 (NRP1) and plexin-B1 which are essential modulators of embryonic angiogenesis with additional roles in vessel remodelling and arteriogenesis. Under conditions of β-adrenoceptor inhibition, the endogenous generation of nitric oxide (NO) as well as the phosphorylation of endothelial nitric oxide synthase (eNOS) was decreased in embryoid bodies, whereas an increase in NO generation was observed with the NO donor S-nitroso-N-acetyl-D,L-penicillamine (SNAP). Consequently, vasculogenesis of ES cells was restored upon treatment of differentiating ES cells with β-adrenoceptor antagonists in the presence of NO donor. In summary, our data suggest that β-blockers impair vasculogenesis of ES cells by interfering with NO generation which could be the explanation for their anti-angiogenic effects in infantile hemangioma.

  5. Discovery of high affinity ligands for β2-adrenergic receptor through pharmacophore-based high-throughput virtual screening and docking.

    Science.gov (United States)

    Yakar, Ruya; Akten, Ebru Demet

    2014-09-01

    Novel high affinity compounds for human β2-adrenergic receptor (β2-AR) were searched among the clean drug-like subset of ZINC database consisting of 9,928,465 molecules that satisfy the Lipinski's rule of five. The screening protocol consisted of a high-throughput pharmacophore screening followed by an extensive amount of docking and rescoring. The pharmacophore model was composed of key features shared by all five inactive states of β2-AR in complex with inverse agonists and antagonists. To test the discriminatory power of the pharmacophore model, a small-scale screening was initially performed on a database consisting of 117 compounds of which 53 antagonists were taken as active inhibitors and 64 agonists as inactive inhibitors. Accordingly, 7.3% of the ZINC database subset (729,413 compounds) satisfied the pharmacophore requirements, along with 44 antagonists and 17 agonists. Afterwards, all these hit compounds were docked to the inactive apo form of the receptor using various docking and scoring protocols. Following each docking experiment, the best pose was further evaluated based on the existence of key residues for antagonist binding in its vicinity. After final evaluations based on the human intestinal absorption (HIA) and the blood brain barrier (BBB) penetration properties, 62 hit compounds have been clustered based on their structural similarity and as a result four scaffolds were revealed. Two of these scaffolds were also observed in three high affinity compounds with experimentally known Ki values. Moreover, novel chemical compounds with distinct structures have been determined as potential β2-AR drug candidates.

  6. Involvement of serotoninergic 5-HT1A/2A, alpha-adrenergic and dopaminergic D1 receptors in St. John's wort-induced prepulse inhibition deficit: a possible role of hyperforin.

    Science.gov (United States)

    Tadros, Mariane G; Mohamed, Mohamed R; Youssef, Amal M; Sabry, Gilane M; Sabry, Nagwa A; Khalifa, Amani E

    2009-05-16

    Prepulse inhibition (PPI) of acoustic startle response is a valuable paradigm for sensorimotor gating processes. Previous research showed that acute administration of St. John's wort extract (500 mg/kg, p.o.) to rats caused significant disruption of PPI while elevating monoamines levels in some brain areas. The cause-effect relationship between extract-induced PPI disruption and augmented monoaminergic transmission was studied using different serotoninergic, adrenergic and dopaminergic antagonists. The effects of hypericin and hyperforin, as the main active constituents of the extract, on PPI response were also tested. PPI disruption was prevented after blocking the serotoninergic 5-HT1A and 5-HT2A, alpha-adrenergic and dopaminergic D1 receptors. Results also demonstrated a significant PPI deficit after acute treatment of rats with hyperforin, and not hypericin. In some conditions manifesting disrupted PPI response, apoptosis coexists. Electrophoresis of DNA isolated from brains of hyperforin-treated animals revealed absence of any abnormal DNA fragmentation patterns. It is concluded that serotoninergic 5-HT1A and 5-HT2A, alpha-adrenergic and dopaminergic D1 receptors are involved in the disruptive effect of St. John's wort extract on PPI response in rats. We can also conclude that hyperforin, and not hypericin, is one of the active ingredients responsible for St. John's wort-induced PPI disruption with no relation to apoptotic processes.

  7. Combination of roflumilast with a beta-2 adrenergic receptor agonist inhibits proinflammatory and profibrotic mediator release from human lung fibroblasts

    Directory of Open Access Journals (Sweden)

    Tannheimer Stacey L

    2012-03-01

    Full Text Available Abstract Background Small airway narrowing is an important pathology which impacts lung function in chronic obstructive pulmonary disease (COPD. The accumulation of fibroblasts and myofibroblasts contribute to inflammation, remodeling and fibrosis by production and release of mediators such as cytokines, profibrotic factors and extracellular matrix proteins. This study investigated the effects of the phosphodiesterase 4 inhibitor roflumilast, combined with the long acting β2 adrenergic agonist indacaterol, both approved therapeutics for COPD, on fibroblast functions that contribute to inflammation and airway fibrosis. Methods The effects of roflumilast and indacaterol treatment were characterized on transforming growth factor β1 (TGFβ1-treated normal human lung fibroblasts (NHLF. NHLF were evaluated for expression of the profibrotic mediators endothelin-1 (ET-1 and connective tissue growth factor (CTGF, expression of the myofibroblast marker alpha smooth muscle actin, and fibronectin (FN secretion. Tumor necrosis factor-α (TNF-α was used to induce secretion of chemokine C-X-C motif ligand 10 (CXCL10, chemokine C-C motif ligand 5 (CCL5 and granulocyte macrophage colony-stimulating factor (GM-CSF from NHLF and drug inhibition was assessed. Results Evaluation of roflumilast (1-10 μM showed no significant inhibition alone on TGFβ1-induced ET-1 and CTGF mRNA transcripts, ET-1 and FN protein production, alpha smooth muscle expression, or TNF-α-induced secretion of CXCL10, CCL5 and GM-CSF. A concentration-dependent inhibition of ET-1 and CTGF was shown with indacaterol treatment, and a submaximal concentration was chosen for combination studies. When indacaterol (0.1 nM was added to roflumilast, significant inhibition was seen on all inflammatory and fibrotic mediators evaluated, which was superior to the inhibition seen with either drug alone. Roflumilast plus indacaterol combination treatment resulted in significantly elevated phosphorylation

  8. Methylphenidate and Atomoxetine Enhance Prefrontal Function through alpha[subscript 2]-Adrenergic and Dopamine D[subscript 1] Receptors

    Science.gov (United States)

    Gamo, Nao J.; Wang, Min; Arnsten, Amy F. T.

    2010-01-01

    Objective: This study examined the effects of the attention-deficit/hyperactivity disorder treatments, methylphenidate (MPH) and atomoxetine (ATM), on prefrontal cortex (PFC) function in monkeys and explored the receptor mechanisms underlying enhancement of PFC function at the behavioral and cellular levels. Method: Monkeys performed a working…

  9. Alpha adrenergic receptor blockade increases capillarisation and fractional O2 extraction and lowers blood flow in contracting human skeletal muscle

    DEFF Research Database (Denmark)

    Mortensen, Stefan Peter; Egginton, Stuart; Madsen, Mads

    2017-01-01

    ) in 10 healthy untrained young men before and after 4 weeks treatment with an α1 receptor-antagonist (Terazosin, 1-2 mg day(-1) ). Corresponding biopsies were taken from the m. vastus lateralis. RESULTS: Resting leg blood flow was increased by 57% 6 hours following Terazosin treatment (P... basal capillary-to-fibre ratio was 1.69±0.08 and increased to 1.90±0.08 after treatment (PTerazosin treatment...

  10. Activation of α1A-adrenergic receptor promotes differentiation of rat-1 fibroblasts to a smooth muscle-like phenotype

    Directory of Open Access Journals (Sweden)

    Malik Kafait U

    2004-12-01

    Full Text Available Abstract Background Fibroblasts, as connective tissue cells, are able to transform into another cell type including smooth muscle cells. α1A-adrenergic receptor (α1A-AR stimulation in rat-1 fibroblasts is coupled to cAMP production. However, the significance of an increase in cAMP produced by α1A-AR stimulation on proliferation, hypertrophy and differentiation in these cells is not known. Results Activation of the α1A-AR in rat-1 fibroblasts by phenylephrine (PE inhibited DNA synthesis by 67% and blocked the re-entry of 81% of the cells into S phase of the cell cycle. This cell cycle blockage was associated with hypertrophy characterized by an increase in protein synthesis (64% and cell size. Elevation of cAMP levels decreased both DNA and protein synthesis. Inhibition of adenylyl cyclase or protein kinase A reversed the antiproliferative effect of cAMP analogs but not PE; the hypertrophic effect of PE was also not altered. The functional response of rat-1 cells to PE was accompanied by increased expression of cyclin-dependent kinase (Cdk inhibitors p27kip1 and p21cip1/waf1, which function as negative regulators of the cell cycle. Stimulation of α1A-AR also upregulated the cell cycle regulatory proteins pRb, cyclin D1, Cdk 2, Cdk 4, and proliferating cell nuclear antigen. The antiproliferative effect of PE was blocked by p27kip1 antisense but not sense oligonucleotide. PE also promoted expression of smooth muscle cell differentiation markers (smooth muscle alpha actin, caldesmon, and myosin heavy chain as well as the muscle development marker MyoD. Conclusions Stimulation of α1A-AR promotes cell cycle arrest, hypertrophy and differentiation of rat-1 fibroblasts into smooth muscle-like cells and expression of negative cell cycle regulators by a mechanism independent of the cAMP/PKA signaling pathway.

  11. The beta2 adrenergic receptor Gln27Glu polymorphism affects insulin resistance in patients with heart failure: possible modulation by choice of beta blocker.

    Science.gov (United States)

    Vardeny, Orly; Detry, Michelle A; Moran, John J M; Johnson, Maryl R; Sweitzer, Nancy K

    2008-12-01

    Insulin resistance is prevalent in heart failure (HF) patients, and beta2 adrenergic receptors (beta2-AR) are involved in glucose homeostasis. We hypothesized that beta2-AR Gln27Glu and Arg16Gly polymorphisms affect insulin resistance in HF patients, and we explored if effects of beta2-AR polymorphisms on glucose handling are modified by choice of beta blocker. We studied 30 nondiabetic adults with HF and a history of systolic dysfunction; 15 were receiving metoprolol succinate, and 15 were receiving carvedilol. We measured fasting glucose, insulin, and insulin resistance, and we determined beta2-AR genotypes at codons 27 and 16. The cohort was insulin resistant with a mean HOMA-IR score of 3.4 (95% CI, 2.3 to 4.5; normal value, 1.0). Patients with the Glu27Glu genotype exhibited higher insulin and HOMA-IR compared to individuals carrying a Gln allele (P = 0.019). Patients taking carvedilol demonstrated lower insulin resistance if also carrying a wild-type allele at codon 27 (fasting insulin, 9.8 +/- 10.5 versus 20.5 +/- 2.1 for variant, P = 0.072; HOMA-IR, 2.4 +/- 2.7 versus 5.1 +/- 0.6, P = 0.074); those on metoprolol succinate had high insulin resistance irrespective of genotype. The beta2-AR Glu27Glu genotype may be associated with higher insulin concentrations and insulin resistance in patients with HF. Future studies are needed to confirm whether treatment with carvedilol may be associated with decreased insulin and insulin resistance in beta2-AR codon 27 Gln carriers.

  12. Flow Cytometric Quantification of Peripheral Blood Cell β-Adrenergic Receptor Density and Urinary Endothelial Cell-Derived Microparticles in Pulmonary Arterial Hypertension.

    Directory of Open Access Journals (Sweden)

    Jonathan A Rose

    Full Text Available Pulmonary arterial hypertension (PAH is a heterogeneous disease characterized by severe angiogenic remodeling of the pulmonary artery wall and right ventricular hypertrophy. Thus, there is an increasing need for novel biomarkers to dissect disease heterogeneity, and predict treatment response. Although β-adrenergic receptor (βAR dysfunction is well documented in left heart disease while endothelial cell-derived microparticles (Ec-MPs are established biomarkers of angiogenic remodeling, methods for easy large clinical cohort analysis of these biomarkers are currently absent. Here we describe flow cytometric methods for quantification of βAR density on circulating white blood cells (WBC and Ec-MPs in urine samples that can be used as potential biomarkers of right heart failure in PAH. Biotinylated β-blocker alprenolol was synthesized and validated as a βAR specific probe that was combined with immunophenotyping to quantify βAR density in circulating WBC subsets. Ec-MPs obtained from urine samples were stained for annexin-V and CD144, and analyzed by a micro flow cytometer. Flow cytometric detection of alprenolol showed that βAR density was decreased in most WBC subsets in PAH samples compared to healthy controls. Ec-MPs in urine was increased in PAH compared to controls. Furthermore, there was a direct correlation between Ec-MPs and Tricuspid annular plane systolic excursion (TAPSE in PAH patients. Therefore, flow cytometric quantification of peripheral blood cell βAR density and urinary Ec-MPs may be useful as potential biomarkers of right ventricular function in PAH.

  13. Exercise does not activate the β3 adrenergic receptor-eNOS pathway, but reduces inducible NOS expression to protect the heart of obese diabetic mice.

    Science.gov (United States)

    Kleindienst, Adrien; Battault, Sylvain; Belaidi, Elise; Tanguy, Stephane; Rosselin, Marie; Boulghobra, Doria; Meyer, Gregory; Gayrard, Sandrine; Walther, Guillaume; Geny, Bernard; Durand, Gregory; Cazorla, Olivier; Reboul, Cyril

    2016-07-01

    Obesity and diabetes are associated with higher cardiac vulnerability to ischemia-reperfusion (IR). The cardioprotective effect of regular exercise has been attributed to β3-adrenergic receptor (β3AR) stimulation and increased endothelial nitric oxide synthase (eNOS) activation. Here, we evaluated the role of the β3AR-eNOS pathway and NOS isoforms in exercise-induced cardioprotection of C57Bl6 mice fed with high fat and sucrose diet (HFS) for 12 weeks and subjected or not to exercise training during the last 4 weeks (HFS-Ex). HFS animals were more sensitive to in vivo and ex vivo IR injuries than control (normal diet) and HFS-Ex mice. Cardioprotection in HFS-Ex mice was not associated with increased myocardial eNOS activation and NO metabolites storage, possibly due to the β3AR-eNOS pathway functional loss in their heart. Indeed, a selective β3AR agonist (BRL37344) increased eNOS activation and had a protective effect against IR in control, but not in HFS hearts. Moreover, iNOS expression, nitro-oxidative stress (protein s-nitrosylation and nitrotyrosination) and ROS production during early reperfusion were increased in HFS, but not in control mice. Exercise normalized iNOS level and reduced protein s-nitrosylation, nitrotyrosination and ROS production in HFS-Ex hearts during early reperfusion. The iNOS inhibitor 1400 W reduced in vivo infarct size in HFS mice to control levels, supporting the potential role of iNOS normalization in the cardioprotective effects of exercise training in HFS-Ex mice. Although the β3AR-eNOS pathway is defective in the heart of HFS mice, regular exercise can protect their heart against IR by reducing iNOS expression and nitro-oxidative stress.

  14. Search for β2 adrenergic receptor ligands by virtual screening via grid computing and investigation of binding modes by docking and molecular dynamics simulations.

    Directory of Open Access Journals (Sweden)

    Qifeng Bai

    Full Text Available We designed a program called MolGridCal that can be used to screen small molecule database in grid computing on basis of JPPF grid environment. Based on MolGridCal program, we proposed an integrated strategy for virtual screening and binding mode investigation by combining molecular docking, molecular dynamics (MD simulations and free energy calculations. To test the effectiveness of MolGridCal, we screened potential ligands for β2 adrenergic receptor (β2AR from a database containing 50,000 small molecules. MolGridCal can not only send tasks to the grid server automatically, but also can distribute tasks using the screensaver function. As for the results of virtual screening, the known agonist BI-167107 of β2AR is ranked among the top 2% of the screened candidates, indicating MolGridCal program can give reasonable results. To further study the binding mode and refine the results of MolGridCal, more accurate docking and scoring methods are used to estimate the binding affinity for the top three molecules (agonist BI-167107, neutral antagonist alprenolol and inverse agonist ICI 118,551. The results indicate agonist BI-167107 has the best binding affinity. MD simulation and free energy calculation are employed to investigate the dynamic interaction mechanism between the ligands and β2AR. The results show that the agonist BI-167107 also has the lowest binding free energy. This study can provide a new way to perform virtual screening effectively through integrating molecular docking based on grid computing, MD simulations and free energy calculations. The source codes of MolGridCal are freely available at http://molgridcal.codeplex.com.

  15. : Glutamate receptor 6 gene and autism

    OpenAIRE

    Jamain, Stéphane; Betancur, Catalina; Quach, Hélène; Philippe, Anne; Fellous, Marc; Giros, Bruno; Gillberg, Christopher; Leboyer, Marion; Bourgeron, Thomas

    2002-01-01

    International audience; A genome scan was previously performed and pointed to chromosome 6q21 as a candidate region for autism. This region contains the glutamate receptor 6 (GluR6 or GRIK2) gene, a functional candidate for the syndrome. Glutamate is the principal excitatory neurotransmitter in the brain and is directly involved in cognitive functions such as memory and learning. We used two different approaches, the affected sib-pair (ASP) method and the transmission disequilibrium test (TDT...

  16. Examination of the role of dopamine D₂ and adrenergic α₂ receptors in resurgence of food seeking.

    Science.gov (United States)

    Pyszczynski, Adam D; Shahan, Timothy A

    2014-09-01

    Resurgence refers to the reappearance of an extinguished operant behavior when reinforcement for an alternative behavior is also subsequently discontinued. Resurgence has been noted as a source of relapse to problem behavior following interventions involving alternative reinforcement, and has also been recently used as an animal model of relapse to drug seeking induced by reinforcement loss. Existing information about the neuropharmacology of resurgence is scarce, but suggests overlap between relapse observed in the resurgence model and relapse observed in reinstatement and renewal models. In the present experiment rats earned food pellets for pressing a target lever in Phase I. In Phase II lever pressing no longer produced food, but food was delivered for an alterative nose poke response. Finally in Phase III, neither response produced food deliveries. Prior to these Phase III sessions, separate groups of rats were injected with 0, 50, or 100 μg/kg of the dopamine D2 receptor antagonist raclopride or 0, 20, or 40 μg/kg of α 2 agonist clonidine. Both doses of raclopride were effective in blocking resurgence, but there was evidence that the higher dose did so via motor rather than motivational impairment. Only the higher dose of clonidine blocked resurgence, but did so with no evidence of motor impairment. Raclopride significantly impacted extinction of the alternative poke at both doses tested, whereas clonidine had no effect at either dose. The results of the present study provide additional information about the neuropharmacology of resurgence, as well as additional evidence of overlap between resurgence, reinstatement, and renewal.

  17. Glucocorticoid receptor-dependent gene regulatory networks.

    Directory of Open Access Journals (Sweden)

    Phillip Phuc Le

    2005-08-01

    Full Text Available While the molecular mechanisms of glucocorticoid regulation of transcription have been studied in detail, the global networks regulated by the glucocorticoid receptor (GR remain unknown. To address this question, we performed an orthogonal analysis to identify direct targets of the GR. First, we analyzed the expression profile of mouse livers in the presence or absence of exogenous glucocorticoid, resulting in over 1,300 differentially expressed genes. We then executed genome-wide location analysis on chromatin from the same livers, identifying more than 300 promoters that are bound by the GR. Intersecting the two lists yielded 53 genes whose expression is functionally dependent upon the ligand-bound GR. Further network and sequence analysis of the functional targets enabled us to suggest interactions between the GR and other transcription factors at specific target genes. Together, our results further our understanding of the GR and its targets, and provide the basis for more targeted glucocorticoid therapies.

  18. Effect of Serum from Chickens Treated with Clenbuterol on Myosin Accumulation, Beta-Adrenergic Receptor Population, and Cyclic AMP Synthesis in Embryonic Chicken Skeletal Muscle Cell Cultures

    Science.gov (United States)

    Young, Ronald B.; Bridge, Kristin Y.; Wuethrich, Andrew J.; Hancock, Deana L.

    2002-01-01

    Broiler chickens at 35 d of age were fed 1 ppm clenbuterol for 14 d. This level of dietary clenbuterol led to 5-7% increases in the weights of leg and breast muscle tissue. At the end of the 14-d period, serum was prepared from both control and clenbuterol-treated chickens, and was then employed as a component of cell culture media at a final concentration of 20% (v/v). Muscle cell cultures were prepared from both the leg and the breast muscle groups of 12-d chick embryos. Treatment groups included control chicken serum to which 10 nM, 50 nM, and 1 uM clenbuterol had been added, as well as cells grown in media containing 10% horse serum. Cultures were subjected to each treatment for 3 d, beginning on the seventh d in culture. Neither the percent fusion nor the number of nuclei in myotubes was significantly affected by any of the treatments. The quantity of myosin heavy chains (MHCs) was not increased by serum from clenbuterol-treated chickens in either breast or leg muscle cultures; however, the MHC quantity was 50-150% higher in cultures grown in control chicken serum to which 10 and 50 nM clenbuterol had also been added. The B-adrenergic receptor (betaAR) population was 4000-7000 betaARs per cell in cultures grown in chicken serum with leg muscle cultures having approximately 25-30% more receptors than breast muscle Culture. Receptor population was not significantly affected by the presence of clenbuterol or by the presence of serum from clenbuterol-treated chickens. In contrast, the betaAR Population in leg and breast muscle cultures grown in the presence of 10% horse serum was 16,000-18,000 betaARs per cell. Basal concentration of cyclic adenosine 3':5'monophosphate (cAMP) was not significantly affected by the treatments. When cultures grown in chicken serum were stimulated for 10 min with 1 uM isoproterenol, limited increases of 12-20% in cAMP Concentration above the. basal levels were observed. However, when cultures grown in the presence of horse serum were

  19. Association of the beta-1 adrenergic receptor carboxyl terminal variants with left ventricular hypertrophy among diabetic and non-diabetic survivors of acute myocardial infarction

    Directory of Open Access Journals (Sweden)

    Hakalahti Anna E

    2010-08-01

    Full Text Available Abstract Background The beta-1 adrenergic receptor (β1AR plays a fundamental role in the regulation of cardiovascular functions. It carries a nonsynonymous single nucleotide polymorphism in its carboxyl terminal tail (Arg389Gly, which has been shown to associate with various echocardiographic parameters linked to left ventricular hypertrophy (LVH. Diabetes mellitus (DM, on the other hand, represents a risk factor for LVH. We investigated the possible association between the Arg389Gly polymorphism and LVH among non-diabetic and diabetic acute myocardial infarction (AMI survivors. Methods The study population consisted of 452 AMI survivors, 20.6% of whom had diagnosed DM. Left ventricular parameters were measured with two-dimensional guided M-mode echocardiography 2-7 days after AMI, and the Arg389Gly polymorphism was determined using a polymerase chain reaction-restriction fragment length polymorphism assay. Results The Arg389 homozygotes in the whole study population had a significantly increased left ventricular mass index (LVMI when compared to the Gly389 carriers (either Gly389 homozygotes or Arg389/Gly389 heterozygotes [62.7 vs. 58.4, respectively (p = 0.023]. In particular, the Arg389 homozygotes displayed thicker diastolic interventricular septal (IVSd measures when compared to the Gly389 carriers [13.2 vs. 12.3 mm, respectively (p = 0.004]. When the euglycemic and diabetic patients were analyzed separately, the latter had significantly increased LVMI and diastolic left ventricular posterior wall (LVPWd values compared to the euglycemic patients [LVMI = 69.1 vs. 58.8 (p = 0.001 and LVPWd = 14.2 vs. 12.3 mm (p Conclusions The data suggest an association between the β1AR Arg389Gly polymorphism and LVH, particularly the septal hypertrophy. The Arg389 variant appears to confer a higher risk of developing LVH than the corresponding Gly389 variant among patients who have suffered AMI. This association cannot be considered to be universal

  20. Targeting beta- and alpha-adrenergic receptors differentially shifts Th1, Th2, and inflammatory cytokine profiles in immune organs to attenuate adjuvant arthritis

    Directory of Open Access Journals (Sweden)

    Dianne eLorton

    2014-08-01

    Full Text Available The sympathetic nervous system (SNS regulates host defense responses and restores homeostasis. SNS-immune regulation is altered in rheumatoid arthritis (RA and rodent models of RA, characterized by nerve remodeling in immune organs and defective adrenergic receptor (AR signaling to immune cell targets that typically promotes or suppresses inflammation via α- and β2-AR activation, respectively, and indirectly drives humoral immunity by blocking Th1 cytokine secretion. Here, we investigate how β2-AR stimulation and/or α-AR blockade at disease onset affects disease pathology and cytokine profiles in relevant immune organs from male Lewis rats with adjuvant-induced arthritis (AA. Rats challenged to induce AA were treated with terbutaline (TERB, a β2-AR agonist (600 μg/kg/day and/or phentolamine (PHEN, an α-AR antagonist (5.0 mg/kg/day or vehicle from disease onset through severe disease. We report that in spleen, mesenteric (MLN and draining lymph node (DLN cells, TERB reduces proliferation, an effect independent of IL-2. TERB also fails to shift Th cytokines from a Th1 to Th2 profile in spleen and MLN (no effect on IFN-γ and DLN (greater IFN-γ cells. In splenocytes, TERB, PHEN and co-treatment (PT promotes an anti-inflammatory profile (greater IL-10 and lowers TNF-α (PT only. In DLN cells, drug treatments do not affect inflammatory profiles, except PT, which raised IL-10. In MLN cells, TERB or PHEN lowers MLN cell secretion of TNF-α or IL-10, respectively. Collectively, our findings indicate disrupted β2-AR, but not α-AR signaling in AA. Aberrant β2-AR signaling consequently derails the sympathetic regulation of lymphocyte expansion, Th cell differentiation, and inflammation in the spleen, DLNs and MLNs that is required for immune system homeostasis. Importantly, this study provides potential mechanisms through which reestablished balance between α- and β2-AR function in the immune system ameliorates inflammation and joint

  1. 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

  2. Beta-adrenergic receptors support attention to extinction learning that occurs in the absence, but not the presence, of a context change

    Science.gov (United States)

    André, Marion Agnès Emma; Wolf, Oliver T.; Manahan-Vaughan, Denise

    2015-01-01

    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 behavior 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 succeeded (on 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. [Beta]-Adrenergic Receptor Activation Rescues Theta Frequency Stimulation-Induced LTP Deficits in Mice Expressing C-Terminally Truncated NMDA Receptor GluN2A Subunits

    Science.gov (United States)

    Moody, Teena D.; Watabe, Ayako M.; Indersmitten, Tim; Komiyama, Noboru H.; Grant, Seth G. N.; O'Dell, Thomas J.

    2011-01-01

    Through protein interactions mediated by their cytoplasmic C termini the GluN2A and GluN2B subunits of NMDA receptors (NMDARs) have a key role in the formation of NMDAR signaling complexes at excitatory synapses. Although these signaling complexes are thought to have a crucial role in NMDAR-dependent forms of synaptic plasticity such as long-term…

  4. The Androgen Receptor Gene Mutations Database.

    Science.gov (United States)

    Gottlieb, B; Lehvaslaiho, H; Beitel, L K; Lumbroso, R; Pinsky, L; Trifiro, M

    1998-01-01

    The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 272 to 309 in the past year. We have expanded the database: (i) by giving each entry an accession number; (ii) by adding information on the length of polymorphic polyglutamine (polyGln) and polyglycine (polyGly) tracts in exon 1; (iii) by adding information on large gene deletions; (iv) by providing a direct link with a completely searchable database (courtesy EMBL-European Bioinformatics Institute). The addition of the exon 1 polymorphisms is discussed in light of their possible relevance as markers for predisposition to prostate or breast cancer. The database is also available on the internet (http://www.mcgill. ca/androgendb/ ), from EMBL-European Bioinformatics Institute (ftp. ebi.ac.uk/pub/databases/androgen ), or as a Macintosh FilemakerPro or Word file (MC33@musica.mcgill.ca).

  5. Regulatory Features for Odorant Receptor Genes in the Mouse Genome.

    Science.gov (United States)

    Degl'Innocenti, Andrea; D'Errico, Anna

    2017-01-01

    The odorant receptor genes, seven transmembrane receptor genes constituting the vastest mammalian gene multifamily, are expressed monogenically and monoallelicaly in each sensory neuron in the olfactory epithelium. This characteristic, often referred to as the one neuron-one receptor rule, is driven by mostly uncharacterized molecular dynamics, generally named odorant receptor gene choice. Much attention has been paid by the scientific community to the identification of sequences regulating the expression of odorant receptor genes within their loci, where related genes are usually arranged in genomic clusters. A number of studies identified transcription factor binding sites on odorant receptor promoter sequences. Similar binding sites were also found on a number of enhancers that regulate in cis their transcription, but have been proposed to form interchromosomal networks. Odorant receptor gene choice seems to occur via the local removal of strongly repressive epigenetic markings, put in place during the maturation of the sensory neuron on each odorant receptor locus. Here we review the fast-changing state of art for the study of regulatory features for odorant receptor genes.

  6. Androgen receptor gene polymorphism in zebra species

    Directory of Open Access Journals (Sweden)

    Hideyuki Ito

    2015-09-01

    Full Text Available Androgen receptor genes (AR have been found to have associations with reproductive development, behavioral traits, and disorders in humans. However, the influence of similar genetic effects on the behavior of other animals is scarce. We examined the loci AR glutamine repeat (ARQ in 44 Grevy's zebras, 23 plains zebras, and three mountain zebras, and compared them with those of domesticated horses. We observed polymorphism among zebra species and between zebra and horse. As androgens such as testosterone influence aggressiveness, AR polymorphism among equid species may be associated with differences in levels of aggression and tameness. Our findings indicate that it would be useful to conduct further studies focusing on the potential association between AR and personality traits, and to understand domestication of equid species.

  7. Night/day changes in pineal expression of >600 genes: central role of adrenergic/cAMP signaling

    DEFF Research Database (Denmark)

    Bailey, Michael J; Coon, Steven L; Carter, John David;

    2009-01-01

    The pineal gland plays an essential role in vertebrate chronobiology by converting time into a hormonal signal, melatonin, which is always elevated at night. Here we have analyzed the rodent pineal transcriptome using Affymetrix GeneChip(R) technology to obtain a more complete description of pineal...

  8. Gene : CBRC-OGAR-01-0843 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available |NP_000674.2| alpha-2C-adrenergic receptor [Homo sapiens] sp|P18825|ADA2C_HUMAN Alpha-2C adrenergic receptor...280399_1 alpha 2C adrenergic receptor [Homo sapiens] gb|AAT02221.1| alpha2C adrenergic receptor [Homo sapi...ens] gb|AAY41059.1| unknown [Homo sapiens] gb|AAI42626.1| Adrenergic, alpha-2C-, receptor [Homo sapi...ens] 1e-166 86% MGVGCPSGCSALYVCSSVWVFVRVWCVYTCARCALCTSSSCTCAHQLTLLVVTQVVEYTSAHARRVKAPIVAVWL

  9. beta-Adrenergic agonist activity of a monoclonal anti-idiotypic antibody.

    Science.gov (United States)

    Guillet, J G; Kaveri, S V; Durieu, O; Delavier, C; Hoebeke, J; Strosberg, A D

    1985-03-01

    Hybridoma cells bearing monoclonal antibody against the beta-adrenergic ligand alprenolol were used as an immunogen to raise monoclonal anti-idiotypic antibodies. Of six anti-idiotypic antibodies, which inhibit ligand binding, three were able to recognize beta-adrenergic receptors. One of them, mAb2B4, an IgM that could be amplified into ascites, binds to the beta-adrenergic catecholamine receptors of intact epidermoid A431 cells and precipitates receptors solubilized from plasma membranes by digitonin. This antibody identifies the beta 2-adrenergic receptor of A431 cells as a single 55-kDa protein and stimulates adenylate cyclase activity. This stimulation is inhibited by the beta-adrenergic antagonist propranolol.

  10. Molecular basis for gene-specific transactivation by nuclear receptors

    DEFF Research Database (Denmark)

    Jørgensen, Mads Aagaard; Siersbæk, Rasmus; Mandrup, Susanne

    2010-01-01

    most likely be accounted for by mechanisms involving receptor-specific interactions with DNA as well as receptor-specific interactions with protein complexes binding to adjacent and distant DNA sequences. Here, we review key molecular aspects of transactivation by NRs with special emphasis......Nuclear receptors (NRs) are key transcriptional regulators of metazoan physiology and metabolism. Different NRs bind to similar or even identical core response elements; however, they regulate transcription in a highly receptor- and gene-specific manner. These differences in gene activation can...... on the recent advances in the molecular mechanisms responsible for receptor- and gene-specific transcriptional activation. This article is part of a Special Issue entitled: Translating nuclear receptors from health to disease....

  11. Gene Transfer and Molecular Cloning of the Human NGF Receptor

    Science.gov (United States)

    Chao, Moses V.; Bothwell, Mark A.; Ross, Alonzo H.; Koprowski, Hilary; Lanahan, Anthony A.; Buck, C. Randall; Sehgal, Amita

    1986-04-01

    Nerve growth factor (NGF) and its receptor are important in the development of cells derived from the neural crest. Mouse L cell transformants have been generated that stably express the human NGF receptor gene transfer with total human DNA. Affinity cross-linking, metabolic labeling and immunoprecipitation, and equilibrium binding with 125I-labeled NGF revealed that this NGF receptor had the same size and binding characteristics as the receptor from human melanoma cells and rat PC12 cells. The sequences encoding the NGF receptor were molecularly cloned using the human Alu repetitive sequence as a probe. A cosmid clone that contained the human NGF receptor gene allowed efficient transfection and expression of the receptor.

  12. Avaliação da influência do polimorfismo do códon 16 do receptor beta-2 adrenérgico na incidência de hipotensão arterial e uso de efedrina em grávidas submetidas à anestesia subaracnoidea Evaluación de la influencia del polimorfismo del codón 16 del receptor beta-2 adrenérgico en la incidencia de hipotensión arterial y uso de efedrina en embarazadas sometidas a la anestesia subaracnoidea Evaluation of the influence of the codon 16 polymorphism of the beta-2 adrenergic receptor gene on the incidence of arterial hypotension and ephedrine use in pregnant patients submitted to subarachnoid anesthesia

    Directory of Open Access Journals (Sweden)

    Edno Magalhães

    2010-06-01

    recientes han venido demostrando su importancia clínica. El objetivo de este trabajo, fue evaluar la influencia del polimorfismo Arg16Gli en la incidencia de hipotensión arterial y el uso de efedrina en parturientas sometidas al bloqueo subaracnoideo para cesárea. MÉTODO: Parturientas sanas (ASA I y II fueron sometidas a la anestesia raquídea para la realización de cesárea electiva (n = 50. Efedrina fue administrada en los casos de hipotensión arterial. La incidencia de hipotensión arterial y la dosis requerida de efedrina para la corrección de la presión arterial fueron comparadas entre los diferentes genotipos encontrados. RESULTADOS: El genotipo que más prevaleció fue el Arg16Gli (60%, n = 30 seguido por el Gli16Gli (26%, n = 13 y Arg16Arg (14%, n = 7. No se observaron diferencias entre las características básicas de los genotipos. Con relación al genotipo Arg16Arg, el genotipo Gli16Gli presentó un aumento de la razón de riesgo de hipotensión arterial (hazard ratio de 3,95 veces (IC 95% 0,86-18,11; p = 0,076, mientras que el genotipo Arg16Gli presentó un aumento de 4,83 veces (IC 95% 1,13-20,50; p = 0,033. Las parturientas con genotipo Arg16Arg, necesitaron como promedio 6,4 ± 8,5 mg de efedrina para la corrección de la hipotensión arterial, mientras que las del genotipo Arg16Gli necesitaron 19,5 ± 15,9 mg (p = 0,0445; IC 95% 0.3325-25.78 y las del tipo Gli16Gli 19,2 ± 14,3 (p = 0,0445, IC 95% 0.3476-25.26. CONCLUSIONES: Los resultados mostraron que la variante genética Arg16Arg presenta una menor incidencia de hipotensión arterial y que menores dosis de efedrina fueron necesarias para el reestablecimiento de la normotensión arterial en las pacientes con ese perfil genético. Concluimos que el genotipo Arg16Arg le da una mayor estabilidad de presión a las parturientas sometidas a la anestesia raquídea para cesárea.BACKGROUND AND OBJECTIVES: The beta-2 adrenergic receptor gene has several polymorphisms. Recent studies have demonstrated the

  13. Effects of Shexiangbaoxin pills on the expression of cardiac α1-and β-adrenergic receptor subtypes in rat hearts with heart failure induced by myocardial infarction

    Institute of Scientific and Technical Information of China (English)

    LI Yan-fang; CAO Fang-fang; LIU Fei; BAI Xue-yuan; L(U) Yang

    2012-01-01

    Background Chronic heart failure (CHF) had been characterized as an activated sympathetic system leading to the alteration of adrenergic receptor (AR) levels in the heart.Thus far,not much research has been done with regard to traditional Chinese medical treatment for CHF.We investigated the effect of Shexiangbaoxin pills (SXBXP) on the function of the heart and the expression of α1-AR and β-AR subtypes in the messenger RNA (mRNA) levels and protein levels of non-infarction left ventricular tissue from rats with CHF induced by myocardial infarction.Methods Models of CHF were established by left anterior descending coronary artery ligature.Fifty-four Wistar rats were randomly divided into five groups:normal control group (group A),sham operation group (group B),CHF model group (group C),positive medicine control group (group D),and small-dose SXBXP group (group E) and large-dose SXBXP group (group F),deployed intragastrically.Cardiac function was examined by echocardiography before and after therapy; mRNA expressed levels were measured by semiquantitative reverse transcription polymerase chain reaction (RT-PCR) for β1-AR,β2-AR,β3-AR,α1A-AR,α1B-AR,and α1D-AR; protein levels were measured by Western blotting analysis for β1-AR,β2-AR,α1A-AR,α1B-AR,and α1D-AR in non-infarction left ventricular tissue.Results There was no significant difference in the left ventricular ejection fraction (LVEF) between groups A and B.Compared to group B,LVEF of groups C,D,E,and F were significantly decreased (P <0.01) before therapy.After therapy,compared to group C,LVEF of group F was significantly improved (P <0.05).Compared to group B,β1-AR and α1B-AR expressed levels were markedly decreased (P <0.05),α1A-AR and β3-AR were significantly increased (P <0.01 ) in group C,and in both mRNA and protein expressed levels β2-AR had no significant difference between groups B and C (P >0.05).α1D-AR mRNA levels were unchanged in each group (P >0.05),but α1D

  14. Effects related to gene-gene interactions of peroxisome proliferator-activated receptor on essential hypertension

    Institute of Scientific and Technical Information of China (English)

    俞浩

    2013-01-01

    Objective To explore the impact of the gene-gene interaction among the single nucleotide polymorphisms(SNPs) of peroxisome proliferator-activated receptorα/δ/γ on essential hypertension(EH).Methods

  15. Beta2-adrenergic signaling affects the phenotype of human cardiac progenitor cells through EMT modulation.

    Science.gov (United States)

    Pagano, Francesca; Angelini, Francesco; Siciliano, Camilla; Tasciotti, Julia; Mangino, Giorgio; De Falco, Elena; Carnevale, Roberto; Sciarretta, Sebastiano; Frati, Giacomo; Chimenti, Isotta

    2017-01-15

    Human cardiac progenitor cells (CPCs) offer great promises to cardiac cell therapy for heart failure. Many in vivo studies have shown their therapeutic benefits, paving the way for clinical translation. The 3D model of cardiospheres (CSs) represents a unique niche-like in vitro microenvironment, which includes CPCs and supporting cells. CSs have been shown to form through a process mediated by epithelial-to-mesenchymal transition (EMT). β2-Adrenergic signaling significantly affects stem/progenitor cells activation and mobilization in multiple tissues, and crosstalk between β2-adrenergic signaling and EMT processes has been reported. In the present study, we aimed at investigating the biological response of CSs to β2-adrenergic stimuli, focusing on EMT modulation in the 3D culture system of CSs. We treated human CSs and CS-derived cells (CDCs) with the β2-blocker butoxamine (BUT), using either untreated or β2 agonist (clenbuterol) treated CDCs as control. BUT-treated CS-forming cells displayed increased migration capacity and a significant increase in their CS-forming ability, consistently associated with increased expression of EMT-related genes, such as Snai1. Moreover, long-term BUT-treated CDCs contained a lower percentage of CD90+ cells, and this feature has been previously correlated with higher cardiogenic and therapeutic potential of the CDCs population. In addition, long-term BUT-treated CDCs had an increased ratio of collagen-III/collagen-I gene expression levels, and showed decreased release of inflammatory cytokines, overall supporting a less fibrosis-prone phenotype. In conclusion, β2 adrenergic receptor block positively affected the stemness vs commitment balance within CSs through the modulation of type1-EMT (so called "developmental"). These results further highlight type-1 EMT to be a key process affecting the features of resident cardiac progenitor cells, and mediating their response to the microenvironment.

  16. Genetic and Functional Analysis of Androgen Receptor Gene Mutations

    NARCIS (Netherlands)

    H.T. Brüggenwirth (Hennie)

    1998-01-01

    textabstractNuclear hormone receptors (NHRs) are intermediary factors through which extracellular signals regulate expression of genes that are involved in homeostasis, development, and differentiation (Beato et al. '995, Mangelsdorf and Evans 1995). These receptors are characterized by a modular st

  17. Regulation of gonadotropin receptor gene expression

    NARCIS (Netherlands)

    A.P.N. Themmen (Axel); R. Kraaij (Robert); J.A. Grootegoed (Anton)

    1994-01-01

    textabstractThe receptors for the gonadotropins differ from the other G protein-coupled receptors by having a large extracellular hormone-binding domain, encoded by nine or ten exons. Alternative splicing of the large pre-mRNA of approximately 100 kb can result in mRNA species that encode truncated

  18. Impact of estrogen receptor α gene and oxytocin receptor gene polymorphisms on female sexuality

    Directory of Open Access Journals (Sweden)

    Anastasia K Armeni

    2017-02-01

    Full Text Available Over the past decades, research attention has increasingly been paid to the neurobiological component of sexual behavior. The aim of the present study was to investigate the correlation of estrogen receptor α (ERA gene polymorphism (rs2234693-PvuII (T→C substitution and oxytocin receptor gene polymorphism (rs53576 (G→A substitution with sexuality parameters of young, healthy women. One hundred thirty-three Greek heterosexual women, students in higher education institutions, 20–25 years of age, sexually active, with normal menstrual cycles (28–35 days, were recruited in the study. Exclusion criteria were chronic and/or major psychiatric diseases, use of oral contraceptive pills (OCs, polycystic ovary syndrome (PCOS, thyroid diseases as well as drugs that are implicated in hypothalamus–pituitary–gonadal axis. T allele (wildtype of rs2234693 (PvuII polymorphism of ERA gene was correlated with increased levels of arousal and lubrication, whereas A allele (polymorphic of rs53576 (OXTR polymorphism was correlated with increased arousal levels. The simultaneous presence of both T allele of rs2234693 (PvuII and A allele of rs53576 (OXTR polymorphisms (T + A group was correlated with increased arousal, orgasm levels as well as female sexual function index full score. To our knowledge, this is the first study to investigate the interaction between ERA and OXTR with regard to sexual function in women. Female sexuality is a complex behavioral trait that encompasses both biological and psychological components. It seems that variability in female sexual response stems from genetic variability that characterizes endocrine, neurotransmitter and central nervous system influences.

  19. Impact of estrogen receptor α gene and oxytocin receptor gene polymorphisms on female sexuality.

    Science.gov (United States)

    Armeni, Anastasia K; Assimakopoulos, Konstantinos; Marioli, Dimitra; Koika, Vassiliki; Michaelidou, Euthychia; Mourtzi, Niki; Iconomou, Gregoris; Georgopoulos, Neoklis A

    2017-01-01

    Over the past decades, research attention has increasingly been paid to the neurobiological component of sexual behavior. The aim of the present study was to investigate the correlation of estrogen receptor α (ERA) gene polymorphism (rs2234693-PvuII) (T→C substitution) and oxytocin receptor gene polymorphism (rs53576) (G→A substitution) with sexuality parameters of young, healthy women. One hundred thirty-three Greek heterosexual women, students in higher education institutions, 20-25 years of age, sexually active, with normal menstrual cycles (28-35 days), were recruited in the study. Exclusion criteria were chronic and/or major psychiatric diseases, use of oral contraceptive pills (OCs), polycystic ovary syndrome (PCOS), thyroid diseases as well as drugs that are implicated in hypothalamus-pituitary-gonadal axis. T allele (wildtype) of rs2234693 (PvuII) polymorphism of ERA gene was correlated with increased levels of arousal and lubrication, whereas A allele (polymorphic) of rs53576 (OXTR) polymorphism was correlated with increased arousal levels. The simultaneous presence of both T allele of rs2234693 (PvuII) and A allele of rs53576 (OXTR) polymorphisms (T + A group) was correlated with increased arousal, orgasm levels as well as female sexual function index full score. To our knowledge, this is the first study to investigate the interaction between ERA and OXTR with regard to sexual function in women. Female sexuality is a complex behavioral trait that encompasses both biological and psychological components. It seems that variability in female sexual response stems from genetic variability that characterizes endocrine, neurotransmitter and central nervous system influences.

  20. Stress and glucocorticoids impair memory retrieval via β2-adrenergic, Gi/o-coupled suppression of cAMP signaling.

    Science.gov (United States)

    Schutsky, Keith; Ouyang, Ming; Castelino, Christina B; Zhang, Lei; Thomas, Steven A

    2011-10-05

    Acute stress impairs the retrieval of hippocampus-dependent memory, and this effect is mimicked by exogenous administration of stress-responsive glucocorticoid hormones. It has been proposed that glucocorticoids affect memory by promoting the release and/or blocking the reuptake of norepinephrine (NE), a stress-responsive neurotransmitter. It has also been proposed that this enhanced NE signaling impairs memory retrieval by stimulating β(1)-adrenergic receptors and elevating levels of cAMP. In contrast, other evidence indicates that NE, β(1), and cAMP signaling is transiently required for the retrieval of hippocampus-dependent memory. To resolve this discrepancy, wild-type rats and mice with and without gene-targeted mutations were stressed or treated with glucocorticoids and/or adrenergic receptor drugs before testing memory for inhibitory avoidance or fear conditioning. Here we report that glucocorticoids do not require NE to impair retrieval. However, stress- and glucocorticoid-induced impairments of retrieval depend on the activation of β(2) (but not β(1))-adrenergic receptors. Offering an explanation for the opposing functions of these two receptors, the impairing effects of stress, glucocorticoids and β(2) agonists on retrieval are blocked by pertussis toxin, which inactivates signaling by G(i/o)-coupled receptors. In hippocampal slices, β(2) signaling decreases cAMP levels and greatly reduces the increase in cAMP mediated by β(1) signaling. Finally, augmenting cAMP signaling in the hippocampus prevents the impairment of retrieval by systemic β(2) agonists or glucocorticoids. These results demonstrate that the β(2) receptor can be a critical effector of acute stress, and that β(1) and β(2) receptors can have quite distinct roles in CNS signaling and cognition.

  1. Characteristics of the mouse genomic histamine H1 receptor gene

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Isao; Taniuchi, Ichiro; Kitamura, Daisuke [Kyushu Univ., Fukuoka (Japan)] [and others

    1996-08-15

    We report here the molecular cloning of a mouse histamine H1 receptor gene. The protein deduced from the nucleotide sequence is composed of 488 amino acid residues with characteristic properties of GTP binding protein-coupled receptors. Our results suggest that the mouse histamine H1 receptor gene is a single locus, and no related sequences were detected. Interspecific backcross analysis indicated that the mouse histamine H1 receptor gene (Hrh1) is located in the central region of mouse Chromosome 6 linked to microphthalmia (Mitfmi), ras-related fibrosarcoma oncogene 1 (Raf1), and ret proto-oncogene (Ret) in a region of homology with human chromosome 3p. 12 refs., 3 figs.

  2. Vitamin D receptor and estrogen receptor gene polymorphisms in postmenopausal Danish women

    DEFF Research Database (Denmark)

    Bagger, Y Z; Hassager, C; Heegaard, Anne-Marie;

    2000-01-01

    To investigate the polymorphisms of the vitamin D receptor (VDR) and estrogen receptor (ER) genes in relation to biochemical markers of bone turnover (serum osteocalcin and urinary collagen type I degradation products (CrossLaps), and to study ER genotypes in relation to serum lipoproteins, blood...

  3. Association of Interleukin 23 Receptor Gene with Sarcoidosis

    Directory of Open Access Journals (Sweden)

    Hyun Soo Kim

    2011-01-01

    Full Text Available Interleukin 23 receptor (IL23R gene has been reported as a genetic factor strongly associated with inflammatory bowel disease, psoriasis, and ankylosing spondylitis. We investigated the association between IL23R gene single nucleotide polymorphisms (SNPs and susceptibility to sarcoidosis, including the clinical manifestation of uveitis.

  4. Comparison of the canine and human olfactory receptor gene repertoires

    NARCIS (Netherlands)

    Quignon, P; Kirkness, E; Cadieu, E; Touleimat, N; Guyon, R; Renier, C; Hitte, C; Andre, C; Fraser, C; Galibert, F

    2003-01-01

    Background: Olfactory receptors (ORs), the first dedicated molecules with which odorants physically interact to arouse an olfactory sensation, constitute the largest gene family in vertebrates, including around 900 genes in human and 1,500 in the mouse. Whereas dogs, like many other mammals, have a

  5. Prolactin receptor and signal transduction to milk protein genes

    Energy Technology Data Exchange (ETDEWEB)

    Djiane, J.; Daniel, N.; Bignon, C. [Unite d`Endocrinologie Moleculaire, Jouy en Josas (France)] [and others

    1994-06-01

    After cloning of the mammary gland prolactin (PRL) receptor cDNA, a functional assay was established using co-transfection of PRL receptor cDNA together with a milk protein promoter/chloramphenicol acetyl transferase (CAT) construct in Chinese hamster ovary (CHO) cells. Different mutants of the PRL receptor were tested in this CAT assay to delimit the domains in the receptor necessary for signal transduction to milk protein genes. In CHO cells stably transfected with PRL receptor cDNA, high numbers of PRL receptor are expressed. By metabolic labeling and immunoprecipitation, expressed PRL receptor was identified as a single species of 100 kDa. Using these cells, we analyzed the effects of PRL on intracellular free Ca{sup ++} concentration. PRL stimulates Ca{sup ++} entry and induces secondary Ca{sup ++} mobilization. The entry of Ca{sup ++} is a result of an increase in K{sup +} conductance that hyperpolarizes the membranes. We have also analyzed tyrosine phosphorylation induced by PRL. In CHO cells stably transfected with PRL receptor cDNA, PRL induced a very rapid and transient tyrosine phosphorylation of a 100-kDa protein which is most probably the PRL receptor. The same finding was obtained in mammary membranes after PRL injection to lactating rabbits. Whereas tyrosine kinase inhibitors genistein and lavendustin were without effect, PRL stimulation of milk protein gene promoters was partially inhibited by 2 {mu}M herbimycin in CHO cells co-transfected with PRL receptor cDNA and the {Beta} lactoglobulin CAT construct. Taken together these observations indicate that the cytoplasmic domain of the PRL receptor interacts with one or several tyrosine kinases, which may represent early postreceptor events necessary for PRL signal transduction to milk protein genes. 14 refs., 4 figs.

  6. Vitamin D receptor gene polymorphism: association with Crohn's disease susceptibility

    OpenAIRE

    Simmons, J.; Mullighan, C; Welsh, K; JEWELL, D

    2000-01-01

    BACKGROUND—The vitamin D receptor (VDR) gene represents a strong positional candidate susceptibility gene for inflammatory bowel disease (IBD). The VDR gene maps to a region on chromosome 12 that has been shown to be linked to IBD by genome screening techniques. It is the cellular receptor for 1,25(OH)2 vitamin D3 (calcitriol) which has a wide range of different regulatory effects on the immune system. IBD is characterised by activation of the mucosal immune system.
AIM—To determine if polymo...

  7. Neuropeptide Y receptor gene y6: multiple deaths or resurrections?

    Science.gov (United States)

    Starbäck, P; Wraith, A; Eriksson, H; Larhammar, D

    2000-10-14

    The neuropeptide Y family of G-protein-coupled receptors consists of five cloned members in mammals. Four genes give rise to functional receptors in all mammals investigated. The y6 gene is a pseudogene in human and pig and is absent in rat, but generates a functional receptor in rabbit and mouse and probably in the collared peccary (Pecari tajacu), a distant relative of the pig family. We report here that the guinea pig y6 gene has a highly distorted nucleotide sequence with multiple frame-shift mutations. One evolutionary scenario may suggest that y6 was inactivated before the divergence of the mammalian orders and subsequently resurrected in some lineages. However, the pseudogene mutations seem to be distinct in human, pig, and guinea pig, arguing for separate inactivation events. In either case, the y6 gene has a quite unusual evolutionary history with multiple independent deaths or resurrections.

  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...... of alpha-adrenergic receptors and had a positive inotropic effect during contractions which was abolished by alpha- as well as by beta-adrenergic blockade. The results indicate that epinephrine has profound effects on contracting muscle, and that these effects are elicited through different combinations...

  9. Dopamine receptor gene expression by enkephalin neurons in rat forebrain

    Energy Technology Data Exchange (ETDEWEB)

    Le Moine, C.; Normand, E.; Guitteny, A.F.; Fouque, B.; Teoule, R.; Bloch, B. (Universite de Bordeaux II (France))

    1990-01-01

    In situ hybridization experiments were performed with brain sections from normal, control and haloperidol-treated rats to identify and map the cells expressing the D2 dopamine receptor gene. D2 receptor mRNA was detected with radioactive or biotinylated oligonucleotide probes. D2 receptor mRNA was present in glandular cells of the pituitary intermediate lobe and in neurons of the substantia nigra, ventral tegmental area, and forebrain, especially in caudate putamen, nucleus accumbens, olfactory tubercle, and piriform cortex. Hybridization with D2 and preproenkephalin A probes in adjacent sections, as well as combined hybridization with the two probes in the same sections, demonstrated that all detectable enkephalin neurons in the striatum contained the D2 receptor mRNA. Large neurons in caudate putamen, which were unlabeled with the preproenkephalin A probe and which may have been cholinergic, also expressed the D2 receptor gene. Haloperidol treatment (14 or 21 days) provoked an increase in mRNA content for D2 receptor and preproenkephalin A in the striatum. This suggests that the increase in D2 receptor number observed after haloperidol treatment is due to increased activity of the D2 gene. These results indicate that in the striatum, the enkephalin neurons are direct targets for dopamine liberated from mesostriatal neurons.

  10. In vitro and in vivo impairment of alpha2-adrenergic receptor-dependent antilipolysis by fatty acids in human adipose tissue.

    Science.gov (United States)

    Gesta, S; Hejnova, J; Berlan, M; Daviaud, D; Crampes, F; Stich, V; Valet, P; Saulnier-Blache, J S

    2001-12-01

    The aim of the present study was to study the influence of fatty acids on the adrenergic control of lipolysis both in vitro and in vivo. Human subcutaneous adipose tissue explants were cultured for 48 h in the presence of 100 microM bromopalmitate (BrPal), and lipolysis was measured in isolated adipocytes. In control conditions, beta-AR-dependent activation of lipolysis by epinephrine was almost undetectable, and could be fully restored by pharmacological blockade of alpha2-AR-dependent antilipolysis. After BrPal treatment, epinephrine became fully lipolytic and was no longer influenced by alpha2-AR-blockade. Radioligand binding analysis revealed that BrPal treatment led to a significant reduction in the coupling of alpha2-AR to G proteins. In parallel, a chronic and significant increase in plasma fatty acids resulting from a 4-day high-fat diet (HFD) was accompanied by an impairment of the amplifying effect of the alpha2-AR antagonist phentolamine on exercise-induced lipolysis (measured in the subcutaneous adipose tissue with the use of a microdialysis probe) normally observed after a low-fat diet. In conclusion, in vitro and in vivo studies showed that fatty acids impair alpha2-AR-dependent antilipolysis.

  11. A lack of α1A-adrenergic receptor-mediated antidepressant-like effects of S-(+)-niguldipine and B8805-033 in the forced swim test.

    Science.gov (United States)

    Kreiner, Grzegorz; Roman, Adam; Zelek-Molik, Agnieszka; Kowalska, Marta; Nalepa, Irena

    2016-06-01

    The α1-adrenergic receptors (α1-ARs), which belong to a G protein-coupled receptor family, consist of three highly homologous subtypes known as α1A-ARs, α1B-ARs, and α1D-ARs. Our previous findings suggested that α1A-ARs are an important target for imipramine and electroconvulsive therapy. The current study sought to evaluate whether S-(+)-niguldipine and B8805-033, two selective antagonists of α1A-ARs, can evoke antidepressant-like effects in the forced swim test in rats. Both compounds were administered at three time points (24, 5, and 1 h before testing), and the effects of three doses (2, 5, and 10 mg/kg) of each compound were investigated. S-(+)-Niguldipine produced no antidepressant-like effects other than a 14% reduction in immobility time at the highest dose. Although B8805-033 at a dose of 2 mg/kg did not influence the rats' behavior, higher B8805-033 doses (5 and 10 mg/kg) produced significant reductions in immobility time (approximately 42 and 44% vs. controls, respectively; P<0.01). However, this effect was abolished by the concomitant administration of WAY100135, a serotonin receptor antagonist, suggesting that the observed antidepressant-like effects of B8805-033 are unrelated to α1A-ARs. Nevertheless, given the current dearth of selective α1A-AR agonists, the question of whether this particular subtype could be involved in antidepressant therapy mechanisms remains unresolved.

  12. Bacterial Adrenergic Sensors Regulate Virulence of Enteric Pathogens in the Gut

    Directory of Open Access Journals (Sweden)

    Cristiano G. Moreira

    2016-06-01

    Full Text Available Enteric pathogens such as enterohemorrhagic Escherichia coli (EHEC and Citrobacter rodentium, which is largely used as a surrogate EHEC model for murine infections, are exposed to several host neurotransmitters in the gut. An important chemical exchange within the gut involves the neurotransmitters epinephrine and/or norepinephrine, extensively reported to increase virulence gene expression in EHEC, acting through two bacterial adrenergic sensors: QseC and QseE. However, EHEC is unable to establish itself and cause its hallmark lesions, attaching and effacing (AE lesions, on murine enterocytes. To address the role of these neurotransmitters during enteric infection, we employed C. rodentium. Both EHEC and C. rodentium harbor the locus of enterocyte effacement (LEE that is necessary for AE lesion formation. Here we show that expression of the LEE, as well as that of other virulence genes in C. rodentium, is also activated by epinephrine and/or norepinephrine. Both QseC and QseE are required for LEE gene activation in C. rodentium, and the qseC and qseE mutants are attenuated for murine infection. C. rodentium has a decreased ability to colonize dopamine β-hydroxylase knockout (Dbh−/− mice, which do not produce epinephrine and norepinephrine. Both adrenergic sensors are required for C. rodentium to sense these neurotransmitters and activate the LEE genes during infection. These data indicate that epinephrine and norepinephrine are sensed by bacterial adrenergic receptors during enteric infection to promote activation of their virulence repertoire. This is the first report of the role of these neurotransmitters during mammalian gastrointestinal (GI infection by a noninvasive pathogen.

  13. The Mouse Solitary Odorant Receptor Gene Promoters as Models for the Study of Odorant Receptor Gene Choice.

    Directory of Open Access Journals (Sweden)

    Andrea Degl'Innocenti

    Full Text Available In vertebrates, several anatomical regions located within the nasal cavity mediate olfaction. Among these, the main olfactory epithelium detects most conventional odorants. Olfactory sensory neurons, provided with cilia exposed to the air, detect volatile chemicals via an extremely large family of seven-transmembrane chemoreceptors named odorant receptors. Their genes are expressed in a monogenic and monoallelic fashion: a single allele of a single odorant receptor gene is transcribed in a given mature neuron, through a still uncharacterized molecular mechanism known as odorant receptor gene choice.Odorant receptor genes are typically arranged in genomic clusters, but a few are isolated (we call them solitary from the others within a region broader than 1 Mb upstream and downstream with respect to their transcript's coordinates. The study of clustered genes is problematic, because of redundancy and ambiguities in their regulatory elements: we propose to use the solitary genes as simplified models to understand odorant receptor gene choice.Here we define number and identity of the solitary genes in the mouse genome (C57BL/6J, and assess the conservation of the solitary status in some mammalian orthologs. Furthermore, we locate their putative promoters, predict their homeodomain binding sites (commonly present in the promoters of odorant receptor genes and compare candidate promoter sequences with those of wild-caught mice. We also provide expression data from histological sections.In the mouse genome there are eight intact solitary genes: Olfr19 (M12, Olfr49, Olfr266, Olfr267, Olfr370, Olfr371, Olfr466, Olfr1402; five are conserved as solitary in rat. These genes are all expressed in the main olfactory epithelium of three-day-old mice. The C57BL/6J candidate promoter of Olfr370 has considerably varied compared to its wild-type counterpart. Within the putative promoter for Olfr266 a homeodomain binding site is predicted. As a whole, our findings

  14. Genes involved in Drosophila glutamate receptor expression and localization

    Directory of Open Access Journals (Sweden)

    Featherstone David E

    2005-06-01

    Full Text Available Abstract Background A clear picture of the mechanisms controlling glutamate receptor expression, localization, and stability remains elusive, possibly due to an incomplete understanding of the proteins involved. We screened transposon mutants generated by the ongoing Drosophila Gene Disruption Project in an effort to identify the different types of genes required for glutamate receptor cluster development. Results To enrich for non-silent insertions with severe disruptions in glutamate receptor clustering, we identified and focused on homozygous lethal mutants in a collection of 2185 BG and KG transposon mutants generated by the BDGP Gene Disruption Project. 202 lethal mutant lines were individually dissected to expose glutamatergic neuromuscular junctions, stained using antibodies that recognize neuronal membrane and the glutamate receptor subunit GluRIIA, and viewed using laser-scanning confocal microscopy. We identified 57 mutants with qualitative differences in GluRIIA expression and/or localization. 84% of mutants showed loss of receptors and/or clusters; 16% of mutants showed an increase in receptors. Insertion loci encode a variety of protein types, including cytoskeleton proteins and regulators, kinases, phosphatases, ubiquitin ligases, mucins, cell adhesion proteins, transporters, proteins controlling gene expression and protein translation, and proteins of unknown/novel function. Expression pattern analyses and complementation tests, however, suggest that any single mutant – even if a mutant gene is uniquely tagged – must be interpreted with caution until the mutation is validated genetically and phenotypically. Conclusion Our study identified 57 transposon mutants with qualitative differences in glutamate receptor expression and localization. Despite transposon tagging of every insertion locus, extensive validation is needed before one can have confidence in the role of any individual gene. Alternatively, one can focus on the

  15. Androgen receptor gene mutation, rearrangement, polymorphism.

    Science.gov (United States)

    Eisermann, Kurtis; Wang, Dan; Jing, Yifeng; Pascal, Laura E; Wang, Zhou

    2013-09-01

    Genetic aberrations of the androgen receptor (AR) caused by mutations, rearrangements, and polymorphisms result in a mutant receptor that has varied functions compared to wild type AR. To date, over 1,000 mutations have been reported in the AR with most of these being associated with androgen insensitivity syndrome (AIS). While mutations of AR associated with prostate cancer occur less often in early stage localized disease, mutations in castration-resistant prostate cancer (CRPC) patients treated with anti-androgens occur more frequently with 10-30% of these patients having some form of mutation in the AR. Resistance to anti-androgen therapy usually results from gain-of-function mutations in the LBD such as is seen with bicalutamide and more recently with enzalutamide (MDV3100). Thus, it is crucial to investigate these new AR mutations arising from drug resistance to anti-androgens and other small molecule pharmacological agents.

  16. 抗哮喘药物β2肾上腺素受体激动剂的药物基因组学研究进展%Pharmacogenomics of β2-Adrenergic Receptor Agonists in Asthma Therapy

    Institute of Scientific and Technical Information of China (English)

    李浩; 王永庆; 孟玲; 刘菲; 龚晓健; 魏继福

    2013-01-01

    尽管目前临床上用于治疗哮喘的药物有许多种,但这些药物对部分患者的疗效却很差.有证据表明这种个体差异与个人的基因差异密切相关.本文主要针对临床上常用的治疗哮喘的药物B2-肾上腺素受体激动剂的药物基因组学进行综述,并提出了今后有关这一领域的研究方向,用以提高药物治疗效果,减少副作用,并降低患者的治疗费用.%Despite there are several classes of asthma medications clinically available, a significant portion of patients fail to respond to these therapeutic agents. Evidence suggests that genetic factors may partly mediate the heterogeneity in asthma treatment responses. This review focuses on one of the major classes of asthma medications—β2 -adrenergic receptor agonists, discusses important findings in asthma pharmacogenetic and pharmacogenomic studies and proposes future research directions in this field in order to improve therapeutic outcome, minimize side effects and lead to a more cost-effective care.

  17. Haplotype structure of the beta2-adrenergic receptor gene in 814 Danish Caucasian subjects and association with body mass index

    DEFF Research Database (Denmark)

    Jensen, Mette Kamp; Nielsen, Morten; Koefoed, Pernille

    2009-01-01

    with body mass index (BMI). The SNPs showed organization into 13 distinct haplotypes and 41 haplotype pairs. The study identified four common haplotypes: ACCCC (10.1 +/- 0.3 %), ACCCG (27.9 +/- 0.3 %), GCCAC (10.8 +/- 0.1 %) and GGCCG (41.0 +/- 0.2 %) (frequencies (SD), seen in 91 % of the population....... In the total population (mean age +/- SD: 50 +/- 16 years), BMI was not related to haplotype pairs, individual SNPs or allelic haplotypes. However, in subjects ... to individual SNPs. In subjects subjects (BMI

  18. Peroxisome proliferator-activated receptor alpha target genes.

    Science.gov (United States)

    Rakhshandehroo, Maryam; Knoch, Bianca; Müller, Michael; Kersten, Sander

    2010-01-01

    The peroxisome proliferator-activated receptor alpha (PPARα) is a ligand-activated transcription factor involved in the regulation of a variety of processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis. PPARα serves as a molecular target for hypolipidemic fibrates drugs which bind the receptor with high affinity. Furthermore, PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds. PPARα governs biological processes by altering the expression of a large number of target genes. Accordingly, the specific role of PPARα is directly related to the biological function of its target genes. Here, we present an overview of the involvement of PPARα in lipid metabolism and other pathways through a detailed analysis of the different known or putative PPARα target genes. The emphasis is on gene regulation by PPARα in liver although many of the results likely apply to other organs and tissues as well.

  19. Peroxisome Proliferator-Activated Receptor Alpha Target Genes

    Directory of Open Access Journals (Sweden)

    Maryam Rakhshandehroo

    2010-01-01

    Full Text Available The peroxisome proliferator-activated receptor alpha (PPARα is a ligand-activated transcription factor involved in the regulation of a variety of processes, ranging from inflammation and immunity to nutrient metabolism and energy homeostasis. PPARα serves as a molecular target for hypolipidemic fibrates drugs which bind the receptor with high affinity. Furthermore, PPARα binds and is activated by numerous fatty acids and fatty acid-derived compounds. PPARα governs biological processes by altering the expression of a large number of target genes. Accordingly, the specific role of PPARα is directly related to the biological function of its target genes. Here, we present an overview of the involvement of PPARα in lipid metabolism and other pathways through a detailed analysis of the different known or putative PPARα target genes. The emphasis is on gene regulation by PPARα in liver although many of the results likely apply to other organs and tissues as well.

  20. Beta(3)-adrenergic signaling acutely down regulates adipose triglyceride lipase in brown adipocytes.

    Science.gov (United States)

    Deiuliis, Jeffrey A; Liu, Li-Fen; Belury, Martha A; Rim, Jong S; Shin, Sangsu; Lee, Kichoon

    2010-06-01

    Mice exposed to cold rely upon brown adipose tissue (BAT)-mediated nonshivering thermogenesis to generate body heat using dietary glucose and lipids from the liver and white adipose tissue. In this report, we investigate how cold exposure affects the PI3 K/Akt signaling cascade and the expression of genes involved in lipid metabolism and trafficking in BAT. Cold exposure at an early time point led to the activation of the PI3 K/Akt, insulin-like signaling cascade followed by a transient decrease in adipose triglyceride lipase (ATGL) gene and protein expression in BAT. To further investigate how cold exposure-induced signaling altered ATGL expression, cultured primary brown adipocytes were treated with the beta(3)-adrenergic receptor (beta(3)AR) agonist CL 316,243 (CL) resulting in activation of PI3 K/Akt, ERK 1/2, and p38 signaling pathways and significantly decreased ATGL protein levels. ATGL protein levels decreased significantly 30 min post CL treatment suggesting protein degradation. Inhibition of PKA signaling by H89 rescued ATGL levels. The effects of PKA signaling on ATGL were shown to be independent of relevant pathways downstream of PKA such as PI3 K/Akt, ERK 1/2, and p38. However, CL treatment in 3T3-L1 adipocytes did not decrease ATGL protein and mRNA expression, suggesting a distinct response in WAT to beta3-adrenergic agonism. Transitory effects, possibly attributed to acute Akt activation during the early recruitment phase, were noted as well as stable changes in gene expression which may be attributed to beta3-adrenergic signaling in BAT.

  1. Mu Opioid Receptor Gene: New Point Mutations in Opioid Addicts

    OpenAIRE

    Dinarvand, Amin; Goodarzi, Ali; Vousooghi, Nasim; Hashemi, Mehrdad; Dinarvand, Rasoul; Ostadzadeh, Fahimeh; Khoshzaban, Ahad; Zarrindast, Mohammad-Reza

    2014-01-01

    Introduction Association between single-nucleotide polymorphisms (SNPs) in mu opioid receptor gene and drug addiction has been shown in various studies. Here, we have evaluated the existence of polymorphisms in exon 3 of this gene in Iranian population and investigated the possible association between these mutations and opioid addiction. Methods 79 opioid-dependent subjects (55 males, 24 females) and 134 non-addict or control individuals (74 males, 60 females) participated in the study. Geno...

  2. Diverse growth hormone receptor gene mutations in Laron syndrome.

    OpenAIRE

    Berg, M.A.; Argente, J.; Chernausek, S; Gracia, R.; Guevara-Aguirre, J; Hopp, M; Pérez-Jurado, L; Rosenbloom, A; Toledo,S.P.; Francke, U.

    1993-01-01

    To better understand the molecular genetic basis and genetic epidemiology of Laron syndrome (growth-hormone insensitivity syndrome), we analyzed the growth-hormone receptor (GHR) genes of seven unrelated affected individuals from the United States, South America, Europe, and Africa. We amplified all nine GHR gene exons and splice junctions from these individuals by PCR and screened the products for mutations by using denaturing gradient gel electrophoresis (DGGE). We identified a single GHR g...

  3. Dynamic evolution of bitter taste receptor genes in vertebrates

    OpenAIRE

    Jones Gareth; Dong Dong; Zhang Shuyi

    2009-01-01

    Abstract Background Sensing bitter tastes is crucial for many animals because it can prevent them from ingesting harmful foods. This process is mainly mediated by the bitter taste receptors (T2R), which are largely expressed in the taste buds. Previous studies have identified some T2R gene repertoires, and marked variation in repertoire size has been noted among species. However, the mechanisms underlying the evolution of vertebrate T2R genes remain poorly understood. Results To better unders...

  4. Metabolic response to various beta-adrenoceptor agonists in beta3-adrenoceptor knockout mice: evidence for a new beta-adrenergic receptor in brown adipose tissue.

    Science.gov (United States)

    Preitner, F; Muzzin, P; Revelli, J P; Seydoux, J; Galitzky, J; Berlan, M; Lafontan, M; Giacobino, J P

    1998-08-01

    The beta3-adrenoceptor plays an important role in the adrenergic response of brown and white adipose tissues (BAT and WAT). In this study, in vitro metabolic responses to beta-adrenoceptor stimulation were compared in adipose tissues of beta3-adrenoceptor knockout and wild type mice. The measured parameters were BAT fragment oxygen uptake (MO2) and isolated white adipocyte lipolysis. In BAT of wild type mice (-)-norepinephrine maximally stimulated MO2 4.1+/-0.8 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (dobutamine 5.1+/-0.3, terbutaline 5.3+/-0.3 and CL 316,243 4.8+/-0.9 fold, respectively); in BAT of beta3-adrenoceptor knockout mice, the beta1- and beta2-responses were fully conserved. In BAT of wild type mice, the beta1/beta2-antagonist and beta3-partial agonist CGP 12177 elicited a maximal MO2 response (4.7+/-0.4 fold). In beta3-adrenoceptor knockout BAT, this response was fully conserved despite an absence of response to CL 316,243. This unexpected result suggests that an atypical beta-adrenoceptor, distinct from the beta1-, beta2- and beta3-subtypes and referred to as a putative beta4-adrenoceptor is present in BAT and that it can mediate in vitro a maximal MO2 stimulation. In isolated white adipocytes of wild type mice, (-)-epinephrine maximally stimulated lipolysis 12.1+/-2.6 fold. Similar maximal stimulations were obtained with beta1-, beta2- or beta3-adrenoceptor selective agonists (TO509 12+/-2, procaterol 11+/-3, CL 316,243 11+/-3 fold, respectively) or with CGP 12177 (7.1+/-1.5 fold). In isolated white adipocytes of beta3-adrenoceptor knockout mice, the lipolytic responses to (-)epinephrine, to the beta1-, beta2-, beta3-adrenoceptor selective agonists and to CGP 12177 were almost or totally depressed, whereas those to ACTH, forskolin and dibutyryl cyclic AMP were conserved.

  5. Metabolic response to various β-adrenoceptor agonists in β3-adrenoceptor knockout mice: Evidence for a new β-adrenergic receptor in brown adipose tissue

    Science.gov (United States)

    Preitner, Frédéric; Muzzin, Patrick; Revelli, Jean-Pierre; Seydoux, Josiane; Galitzky, Jean; Berlan, Michel; Lafontan, Max; Giacobino, Jean-Paul

    1998-01-01

    The β3-adrenoceptor plays an important role in the adrenergic response of brown and white adipose tissues (BAT and WAT). In this study, in vitro metabolic responses to β-adrenoceptor stimulation were compared in adipose tissues of β3-adrenoceptor knockout and wild type mice. The measured parameters were BAT fragment oxygen uptake (MO2) and isolated white adipocyte lipolysis. In BAT of wild type mice (−)-norepinephrine maximally stimulated MO2 4.1±0.8 fold. Similar maximal stimulations were obtained with β1-,β2- or β3-adrenoceptor selective agonists (dobutamine 5.1±0.3, terbutaline 5.3±0.3 and CL 316,243 4.8±0.9 fold, respectively); in BAT of β3-adrenoceptor knockout mice, the β1- and β2-responses were fully conserved. In BAT of wild type mice, the β1/β2-antagonist and β3-partial agonist CGP 12177 elicited a maximal MO2 response (4.7±0.4 fold). In β3-adrenoceptor knockout BAT, this response was fully conserved despite an absence of response to CL 316,243. This unexpected result suggests that an atypical β-adrenoceptor, distinct from the β1-, β2- and β3-subtypes and referred to as a putative β4-adrenoceptor is present in BAT and that it can mediate in vitro a maximal MO2 stimulation. In isolated white adipocytes of wild type mice, (−)-epinephrine maximally stimulated lipolysis 12.1±2.6 fold. Similar maximal stimulations were obtained with β1-, β2- or β3-adrenoceptor selective agonists (TO509 12±2, procaterol 11±3, CL 316,243 11±3 fold, respectively) or with CGP 12177 (7.1±1.5 fold). In isolated white adipocytes of β3-adrenoceptor knockout mice, the lipolytic responses to (−)epinephrine, to the β1-, β2-, β3-adrenoceptor selective agonists and to CGP 12177 were almost or totally depressed, whereas those to ACTH, forskolin and dibutyryl cyclic AMP were conserved. PMID:9756384

  6. [The role of alpha2-adrenergic and I1-imidazoline receptors in the effects of clonidine and moxonidine on isolated large intestine of mice].

    Science.gov (United States)

    Kozaeva, L P; Korobov, N V; Medvedev, O S

    2005-01-01

    The ability of clonidine and moxonidine to interact with alpha2-adreno- and I1-imidazoline receptors was studied on isolated segments of large intestine of mice. Both drugs induced dose-dependent contractions in longitudinal muscles of the intestine segments. In both cases, the drug action was almost equally decreased by pretreatment with of yohimbine (alpha2-adrenoreceptor agonist with low affinity to I1-imidazoline receptors) and efaroxan (I1-imidazoline receptor agonist with low affinity to alpha2-adrenoreceptors). Analysis of the ratios of the antagonist activities (pA2) of yohimbine and efaroxan with respect to clonidine and moxonidine, as well as the relative selectivity of the two antagonists suggested that the action of both drugs on the large intestine is realized predominantly via alpha2-adrenoreceptors.

  7. The arginine of the DRY motif in transmembrane segment III functions as a balancing micro-switch in the activation of the β2-adrenergic receptor

    DEFF Research Database (Denmark)

    Hansen, Louise Valentin; Groenen, Marleen; Nygaard, Rie

    2012-01-01

    (s) signaling, arrestin mobilization, and internalization upon alanine substitutions. Conversely, TyrV:24 appears to play a role in stabilizing the active receptor conformation as loss of function of G(s) signaling, arrestin mobilization, and receptor internalization was observed upon alanine substitution...... of TyrV:24. The loss of function of the TyrV:24 mutant could partly be rescued by alanine substitution of either AspIII:25 or GluVI:-06 in the double mutants. Surprisingly, removal of the side chain of the ArgIII:26 micro-switch itself had no effect on G(s) signaling and internalization and only reduced...

  8. The biological clock is regulated by adrenergic signaling in brown fat but is dispensable for cold-induced thermogenesis.

    Directory of Open Access Journals (Sweden)

    Siming Li

    Full Text Available The biological clock plays an important role in integrating nutrient and energy metabolism with other cellular processes. Previous studies have demonstrated that core clock genes are rhythmically expressed in peripheral tissues, including the liver, skeletal muscle, pancreatic islets, and white and brown adipose tissues. These peripheral clocks are entrained by physiological cues, thereby aligning the circadian pacemaker to tissue functions. The mechanisms that regulate brown adipose tissue clock in response to physiological signals remain poorly understood. Here we found that the expression of core clock genes is highly responsive to cold exposure in brown fat, but not in white fat. This cold-inducible regulation of the clock network is mediated by adrenergic receptor activation and the transcriptional coactivator PGC-1α. Brown adipocytes in mice lacking a functional clock contain large lipid droplets accompanied by dysregulation of genes involved in lipid metabolism and adaptive thermogenesis. Paradoxically, the "clockless" mice were competent in maintaining core body temperature during cold exposure. These studies elucidated the presence of adrenergic receptor/clock crosstalk that appears to be required for normal thermogenic gene expression in brown fat.

  9. Selection for Genes Encoding Secreted Proteins and Receptors

    Science.gov (United States)

    Klein, Robert D.; Gu, Qimin; Goddard, Audrey; Rosenthal, Arnon

    1996-07-01

    Extracellular proteins play an essential role in the formation, differentiation, and maintenance of multicellular organisms. Despite that, the systematic identification of genes encoding these proteins has not been possible. We describe here a highly efficient method to isolate genes encoding secreted and membrane-bound proteins by using a single-step selection in yeast. Application of this method, termed signal peptide selection, to various tissues yielded 559 clones that appear to encode known or novel extracellular proteins. These include members of the transforming growth factor and epidermal growth factor protein families, endocrine hormones, tyrosine kinase receptors, serine/threonine kinase receptors, seven transmembrane receptors, cell adhesion molecules, extracellular matrix proteins, plasma proteins, and ion channels. The eventual identification of most, or all, extracellular signaling molecules will advance our understanding of fundamental biological processes and our ability to intervene in disease states.

  10. β-adrenergic response modulated by κ-opioid receptor stimulation is attenuated in the cardiomyocytes of rats following chronic hypoxia

    Institute of Scientific and Technical Information of China (English)

    裴建明; 毕辉; 王跃民; 朱妙章; 周京军; 朱运龙

    2003-01-01

    Objective: To study cross-talk between β-opioid receptor and β-adrenoceptor through determination of the intracellular calcium ([Ca2+]i) and cAMP responses in ventricular myocytes of rats subjected to chronic hypoxia for 4 weeks.Methods: Electrically-induced [Ca2+]i transient was measured in single right ventricular myocytes isolated from hearts of chronically hypoxic rats and the age-matched normoxic rats, by using a spectrofluorometric method.Results: β-adrenoceptor stimulation with isoproterenol increased the electrically-induced [Ca2+]i transient and cAMP in myocytes of normoxic rats.U50,488H, a selective β-opioid receptor agonist, at dose (1 μmol/L) which itself had no effect on the [Ca2+]i transient and cAMP, significantly inhibited the effect of isoproterenol.This inhibition was completely abolished in the presence of nor-BNI, a selective κ-opioid receptor antagonist.In the ventricular myocytes of chronically hypoxic rats, the inhibition of U50,488H on the increased [Ca2+]i transient and cAMP with isoproterenol was blunted.Conclusion: Results indicate that the cross-talk between the κ-opioid receptor and β-adrenoceptor is attenuated in the right ventricular myocytes of chronically hypoxic rat.This may be a self-protective mechanism of the heart following chronic hypoxia, which prevents the further decrease of the cardiac function.

  11. Gene specific actions of thyroid hormone receptor subtypes.

    Directory of Open Access Journals (Sweden)

    Jean Z Lin

    Full Text Available There are two homologous thyroid hormone (TH receptors (TRs α and β, which are members of the nuclear hormone receptor (NR family. While TRs regulate different processes in vivo and other highly related NRs regulate distinct gene sets, initial studies of TR action revealed near complete overlaps in their actions at the level of individual genes. Here, we assessed the extent that TRα and TRβ differ in target gene regulation by comparing effects of equal levels of stably expressed exogenous TRs +/- T(3 in two cell backgrounds (HepG2 and HeLa. We find that hundreds of genes respond to T(3 or to unliganded TRs in both cell types, but were not able to detect verifiable examples of completely TR subtype-specific gene regulation. TR actions are, however, far from identical and we detect TR subtype-specific effects on global T(3 response kinetics in HepG2 cells and many examples of TR subtype specificity at the level of individual genes, including effects on magnitude of response to TR +/- T(3, TR regulation patterns and T(3 dose response. Cycloheximide (CHX treatment confirms that at least some differential effects involve verifiable direct TR target genes. TR subtype/gene-specific effects emerge in the context of widespread variation in target gene response and we suggest that gene-selective effects on mechanism of TR action highlight differences in TR subtype function that emerge in the environment of specific genes. We propose that differential TR actions could influence physiologic and pharmacologic responses to THs and selective TR modulators (STRMs.

  12. Adenylyl cyclase type 6 overexpression selectively enhances β-adrenergic and prostacyclin receptor-mediated inhibition of cardiac fibroblast function because of colocalization in lipid rafts

    OpenAIRE

    Liu, Xiaoqiu; Thangavel, Muthusamy; Sun, Shu Qiang; Kaminsky, Joseph; Mahautmr, Penden; Stitham, Jeremiah; Hwa, John; Ostrom, Rennolds S.

    2007-01-01

    Cardiac fibroblasts produce and degrade extracellular matrix and are critical in regulating cardiac remodeling and hypertrophy. Fibroblasts are activated by factors such as transforming growth factor β and inhibited by agents that elevate 3′,5′-cyclic adenosine monophosphate (cAMP) levels. cAMP signal generation and response is known to be compartmentalized in many cell types in part through the colocalization of receptors and specific adenylyl cyclase isoforms in lipid rafts and caveolae. Th...

  13. Synthesis and preliminary evaluation of aminoalkanol derivatives of selected azatricycloundecane system for binding with beta-adrenergic and 5HT1A and 5HT2A receptors.

    Science.gov (United States)

    Kossakowski, Jerzy; Kuran, Bozena

    2007-01-01

    A series of aminoalkanol derivatives of 8,11-dimethyl-3,5-dioxo-4-azatricyclo[5.2.2.0(2,6)] undec-8-en-1-yl acetate and 1,11-dimethyl-4-azatricyclo[5.2.2.0(2,6)]undecane-3,5,8-trione was prepared. The pharmacological profile of selected compounds was evaluated for affinity to beta-adrenoreceptors and serotoninergic receptors (5HT1A and 5HT2A).

  14. Folate receptor gene variants and neural tube defect occurrence

    Energy Technology Data Exchange (ETDEWEB)

    Finnell, R.; Greer, K. [Texas A& M Univ., College Station, TX (United States); Lammer, E. [Stanford Univ., Palo Alto, CA (United States)] [and others

    1994-09-01

    Recent epidemiological evidence shows that periconceptional use of folic acid supplements may prevent 40-50% of neural tube defects (NTDs). The FDA has subsequently recommended folic acid supplementation of all women of childbearing potential, even though the mechanism by which folic acid prevents NTDs is unknown. We investigated genetic variation of a candidate gene, the 5-methyltetrahydrofolate (5-MeTHF) receptor, that may mediate this preventive effect. The receptor concentrates folate within cells and we have localized its mRNA to neuroepithelial cells during neurulation. Our hypothesis is that dysfunctional 5-MeTHF receptors inadequately concentrate folate intracellularly, predisposing infants to NTDs. We have completed SSCP analysis on 3 of the 4 coding exons of the 5-MeTHF receptor gene of 474 infants participating in a large population-based epidemiological case-control study of NTDs in California; genotyping of another 500 infants is ongoing. Genomic DNA was extracted from residual blood spots from newborn screening samples of cases and controls. Genotyping was done blinded to case status. Polymorphisms have been detected for exons 4 and 5; fourteen percent of the infants have exon 5 polymorphisms. Data will be presented on the prevalence of 5-MeTHF receptor polymorphisms among cases and controls. Relationships among the polymorphisms and NTD occurrence may shed light on how folic acid supplementation prevents NTDs.

  15. The adrenergic retulation of the cardiovascular system in the South American rattlesnake, Crotalus durissus

    DEFF Research Database (Denmark)

    Galli, G.L.J.; Jensen, Nini Skovgaard; Abe, A.S.

    2007-01-01

    The present study investigates adrenergic regulation of the systemic and pulmonary circulations of the anaesthetised South American rattlesnake, Crotalus durissus. Haemodynamic measurements were made following bolus injections of adrenaline and adrenergic antagonists administered through a systemic...... arterial catheter. Adrenaline caused a marked systemic vasoconstriction that was abolished by phentolamine, indicating this response was mediated through α-adrenergic receptors. Injection of phentolamine gave rise to a pronounced vasodilatation (systemic conductance (Gsys) more than doubled), while...... injection of propranolol caused a systemic vasoconstriction, pointing to a potent α-adrenergic, and a weaker β-adrenergic tone in the systemic vasculature of Crotalus. Overall, the pulmonary vasculature was far less responsive to adrenergic stimulation than the systemic circulation. Adrenaline caused...

  16. Novel Confocal Microscopic and Flow Cytometric Based Assays to Visualize and Detect the (Beta)2-Adrenergic Receptor in Human Lymphocyte and Mononuclear Cell Populations

    Science.gov (United States)

    Salicru, A. N.; Crucian, B. E.; Nelman, M. A.; Sams, C. F.; Actor, J. K.; Marshall, G. D.

    2006-01-01

    The data show that immunophenotyping of leukocyte populations with (beta)2AR is possible with the commercially available Ab, although the FC assay is limited to the IST as a result of the Ab binding site to the intracellular C-terminus of the 2AR. The FC assay has applications for measuring alterations in total (beta)2AR in human leukocyte populations as changes in fluorescence. In addition, CM confirms that both surface and intracellular compartments stain positively for the (beta)2AR and can be used for qualitative assays that screen for changes in receptor compartmentalization and localization.

  17. Parallel evolution of domesticated Caenorhabditis species targets pheromone receptor genes.

    Science.gov (United States)

    McGrath, Patrick T; Xu, Yifan; Ailion, Michael; Garrison, Jennifer L; Butcher, Rebecca A; Bargmann, Cornelia I

    2011-08-17

    Evolution can follow predictable genetic trajectories, indicating that discrete environmental shifts can select for reproducible genetic changes. Conspecific individuals are an important feature of an animal's environment, and a potential source of selective pressures. Here we show that adaptation of two Caenorhabditis species to growth at high density, a feature common to domestic environments, occurs by reproducible genetic changes to pheromone receptor genes. Chemical communication through pheromones that accumulate during high-density growth causes young nematode larvae to enter the long-lived but non-reproductive dauer stage. Two strains of Caenorhabditis elegans grown at high density have independently acquired multigenic resistance to pheromone-induced dauer formation. In each strain, resistance to the pheromone ascaroside C3 results from a deletion that disrupts the adjacent chemoreceptor genes serpentine receptor class g (srg)-36 and -37. Through misexpression experiments, we show that these genes encode redundant G-protein-coupled receptors for ascaroside C3. Multigenic resistance to dauer formation has also arisen in high-density cultures of a different nematode species, Caenorhabditis briggsae, resulting in part from deletion of an srg gene paralogous to srg-36 and srg-37. These results demonstrate rapid remodelling of the chemoreceptor repertoire as an adaptation to specific environments, and indicate that parallel changes to a common genetic substrate can affect life-history traits across species.

  18. Early developmental 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure decreases chick embryo heart chronotropic response to isoproterenol but not to agents affecting signals downstream of the beta-adrenergic receptor.

    Science.gov (United States)

    Sommer, Rebecca J; Hume, Adam J; Ciak, Jessica M; Vannostrand, John J; Friggens, Megan; Walker, Mary K

    2005-02-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase.

  19. Demonstration of pulmonary {beta}{sub 2}-adrenergic receptor binding in vivo with [{sup 18}F]fluoroethyl-fenoterol in a guinea pig model

    Energy Technology Data Exchange (ETDEWEB)

    Helisch, A.; Schirrmacher, E.; Schirrmacher, R.; Buchholz, H.G.; Bartenstein, P. [University Hospital, Department of Nuclear Medicine, Mainz (Germany); Thews, O.; Dillenburg, W.; Tillmanns, J. [University of Mainz, Institute of Physiology and Pathophysiology, Mainz (Germany); Hoehnemann, S.; Roesch, F. [University of Mainz, Institute of Nuclear Chemistry, Mainz (Germany); Wessler, I. [University of Mainz, Institute of Pharmacology, Mainz (Germany); Buhl, R. [University Hospital, Pulmonary Division, Mainz (Germany)

    2005-11-01

    The new {beta}{sub 2} radioligand (R,R)(S,S) 5-(2-(2-[4-(2-[{sup 18}F]fluoroethoxy)phenyl]-1-methylethylamino)-1-hydroxyethyl)-benzene-1,3-diol ([{sup 18}F]FE-fenoterol; [{sup 18}F]FEFE), a fluoroethylated derivative of racemic fenoterol, was evaluated in vivo and ex vivo using a guinea pig model. Dynamic PET studies over 60 min with [{sup 18}F]FEFE were performed in nine Hartley guinea pigs in which a baseline (group 1, n=3), a predose (group 2, n=3; 2 mg/kg fenoterol 5 min prior to injection of [{sup 18}F]FEFE) or a displacement study (group 3, n=3; 2 mg/kg fenoterol 5 min post injection of [{sup 18}F]FEFE) was conducted. In all animal groups, the lungs could be visualised and semi-quantified separately by calculating uptake ratios to non-specific binding in the neck area. Premedication with non-radioactive fenoterol and displacement tests showed significant reduction of lung uptake, by 94% and 76%, respectively. These data demonstrate specific binding of the new radioligand to the pulmonary {beta}{sub 2}-receptors in accordance with ex vivo measurements. Therefore, [{sup 18}F]FEFE seems to be suitable for the in vivo visualisation and quantification of the pulmonary {beta}{sub 2}-receptor binding in this animal model. (orig.)

  20. Induction of C-FOS, C-MYC and P53 by US -adrenergic receptor (US -AR) stimulation of rat parotid acinar cells (RPAC)

    Energy Technology Data Exchange (ETDEWEB)

    Kousvelari, E.E.; Louis, J.; Curran, T.; Baum, B.J.

    1987-05-01

    Treatment of rats with the US -agonist isoproterenol (ISO) results in dramatically increased parotid gland protein synthesis, processing and cell proliferation. The authors have shown that in RPAC in vitro, US -AR stimulation has similar effect on protein synthesis and processing. Proto-oncogenes have been implicated in growth regulation, differentiation and in mediating some extracellular stimulated events at the level of gene expression. To understand the regulation of cellular events after US -AR stimulation, the expression of c-fos, c-myc and p53 was investigated. RPAC were incubated with or without 10 VM ISO for 15, 30, 60 min. mRNA was isolated from cells and hybridization analysis was performed on nitrocellulose paper-transferred mRNA using TSP-labeled DNA probes. At early time points, the levels of c-fos gene activation in ISO-treated and control cells were comparable. After 60 min of ISO treatment, a sharp 20-30 fold induction of c-fos expression occurred. Similar increases in c-myc and p53 gene expression were observed after 60 min of ISO treatment. The authors data indicate that early effects of US -AR stimulation of RPAC include induction of c-fos, c-myc and p53 gene expression as well as enhanced protein synthesis and processing.

  1. Identification of novel androgen receptor target genes in prostate cancer

    Directory of Open Access Journals (Sweden)

    Gerald William L

    2007-06-01

    Full Text Available Abstract Background The androgen receptor (AR plays critical roles in both androgen-dependent and castrate-resistant prostate cancer (PCa. However, little is known about AR target genes that mediate the receptor's roles in disease progression. Results Using Chromatin Immunoprecipitation (ChIP Display, we discovered 19 novel loci occupied by the AR in castrate resistant C4-2B PCa cells. Only four of the 19 AR-occupied regions were within 10-kb 5'-flanking regulatory sequences. Three were located up to 4-kb 3' of the nearest gene, eight were intragenic and four were in gene deserts. Whereas the AR occupied the same loci in C4-2B (castrate resistant and LNCaP (androgen-dependent PCa cells, differences between the two cell lines were observed in the response of nearby genes to androgens. Among the genes strongly stimulated by DHT in C4-2B cells – D-dopachrome tautomerase (DDT, Protein kinase C delta (PRKCD, Glutathione S- transferase theta 2 (GSTT2, Transient receptor potential cation channel subfamily V member 3 (TRPV3, and Pyrroline-5-carboxylate reductase 1 (PYCR1 – most were less strongly or hardly stimulated in LNCaP cells. Another AR target gene, ornithine aminotransferase (OAT, was AR-stimulated in a ligand-independent manner, since it was repressed by AR siRNA knockdown, but not stimulated by DHT. We also present evidence for in vivo AR-mediated regulation of several genes identified by ChIP Display. For example, PRKCD and PYCR1, which may contribute to PCa cell growth and survival, are expressed in PCa biopsies from primary tumors before and after ablation and in metastatic lesions in a manner consistent with AR-mediated stimulation. Conclusion AR genomic occupancy is similar between LNCaP and C4-2B cells and is not biased towards 5' gene flanking sequences. The AR transcriptionally regulates less than half the genes nearby AR-occupied regions, usually but not always, in a ligand-dependent manner. Most are stimulated and a few are

  2. The Role of Metabotropic Glutamate Receptor Genes in Schizophrenia.

    Science.gov (United States)

    Maj, Carlo; Minelli, Alessandra; Giacopuzzi, Edoardo; Sacchetti, Emilio; Gennarelli, Massimo

    2016-01-01

    Genomic studies revealed two main components in the genetic architecture of schizophrenia, one constituted by common variants determining a distributed polygenic effect and one represented by a large number of heterogeneous rare and highly disruptive mutations. These gene modifications often affect neural transmission and different studies proved an involvement of metabotropic glutamate receptors in schizophrenia phenotype. Through the combination of literature information with genomic data from public repositories, we analyzed the current knowledge on the involvement of genetic variations of the human metabotropic glutamate receptors in schizophrenia and related endophenotypes. Despite the analysis did not reveal a definitive connection, different suggestive associations have been identified and in particular a relevant role has emerged for GRM3 in affecting specific schizophrenia endophenotypes. This supports the hypothesis that these receptors are directly involved in schizophrenia disorder.

  3. Effect of Serum from Chickens Treated with Clenbuterol on Myosin Accumulation, Beta-Adrenergic Receptor Population, and Cyclic AM Synthesis in Embryonic Chicken Skeletal Muscle Cell Cultures

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.; Wuethrich, A. J.; Hancock, D. L.; Whitaker, Ann F. (Technical Monitor)

    2001-01-01

    Broiler chickens at 35 days of age were fed 1 ppm clenbuterol for 14 days. This level of dietary clenbuterol led to 5-7% increases in weights of leg and breast muscle tissue. At the end of the 14-day period, serum was prepared from both control and clenbuterol-treated chickens and was then employed as a component of cell culture media at a final concentration of 20% (v/v). Muscle cell cultures were prepared from both the leg and breast muscle groups of twelve-day chick embryos. Treatment groups included control chicken serum to which 10 nM, 50 nM, and 1 micron clenbuterol had been added, as well as cells grown in media containing 10% horse serum. Cultures were subjected to each treatment for 3 days beginning on the seventh day in culture. Neither the percent fusion nor the number of nuclei in myotubes were significantly affected by any of the treatments. The quantity of MHC was not increased by serum from clenbuterol-treated chickens in either breast and leg muscle cultures; however, MHC quantity was 50- 100% higher in cultures grown in control chicken serum to which 10 nM and 50 nM clenbuterol had also been added. The Beta-AR population was 4,000-7,000 Beta-AR per cell in cultures grown in chicken serum, with leg muscle cultures having approximately 25-30% more receptors than breast muscle cultures. Receptor population was not significantly affected by the presence of clenbuterol or by the presence of serum from clenbuterol-treated chickens. In contrast, the Beta-AR population in leg and breast muscle cultures grown in the presence of 10% horse serum was 18,000-20,000 Beta-AR per cell. Basal concentration of cAMP was not significantly affected by any of the treatments. When cultures grown in chicken serum were stimulated for 10 min with 1 micron isoproterenol, limited increases of 12-20% in cAMP concentration above basal levels were observed. However, when cultures grown in the presence of horse serum were stimulated with 1 micron isoproterenol, increases of 600

  4. Dynamic evolution of bitter taste receptor genes in vertebrates

    Directory of Open Access Journals (Sweden)

    Jones Gareth

    2009-01-01

    Full Text Available Abstract Background Sensing bitter tastes is crucial for many animals because it can prevent them from ingesting harmful foods. This process is mainly mediated by the bitter taste receptors (T2R, which are largely expressed in the taste buds. Previous studies have identified some T2R gene repertoires, and marked variation in repertoire size has been noted among species. However, the mechanisms underlying the evolution of vertebrate T2R genes remain poorly understood. Results To better understand the evolutionary pattern of these genes, we identified 16 T2R gene repertoires based on the high coverage genome sequences of vertebrates and studied the evolutionary changes in the number of T2R genes during birth-and-death evolution using the reconciled-tree method. We found that the number of T2R genes and the fraction of pseudogenes vary extensively among species. Based on the results of phylogenetic analysis, we showed that T2R gene families in teleost fishes are more diverse than those in tetrapods. In addition to the independent gene expansions in teleost fishes, frogs and mammals, lineage-specific gene duplications were also detected in lizards. Furthermore, extensive gains and losses of T2R genes were detected in each lineage during their evolution, resulting in widely differing T2R gene repertoires. Conclusion These results further support the hypotheses that T2R gene repertoires are closely related to the dietary habits of different species and that birth-and-death evolution is associated with adaptations to dietary changes.

  5. Estrogenic receptors a and p gene polymorphisms in postmenopausal osteoporosis

    Directory of Open Access Journals (Sweden)

    K A Maslova

    2008-01-01

    Full Text Available Objective. To assess frequency distribution of estrogenic receptor (ERa and ERfl gene polymorphisms and their influence on bone mineral density (BMD in groups of postmenopausal women with and without osteoporosis (OP. Material and methods. 200 residents of Moscow and Moscow region were divided into two groups considering BMD values according to WHO criteria; OP group and healthy control group Results. Differences of genotype and their combinations frequency distribution between OP and control groups show presence OP risk and protector genotypes. ER gene important role in pathogenesis of postmenopausal osteoporosis and possibility to use these genetic markers for assessment of risk of OP development in Russian population was confirmed.

  6. Interleukin 18 receptor 1 gene polymorphisms are associated with asthma

    DEFF Research Database (Denmark)

    Zhu, Guohua; Whyte, Moira K B; Vestbo, Jørgen;

    2008-01-01

    The interleukin 18 receptor (IL18R1) gene is a strong candidate gene for asthma. It has been implicated in the pathophysiology of asthma and maps to an asthma susceptibility locus on chromosome 2q12. The possibility of association between polymorphisms in IL18R1 and asthma was examined...... by genotyping seven SNPs in 294, 342 and 100 families from Denmark, United Kingdom and Norway and conducting family-based association analyses for asthma, atopic asthma and bronchial hyper-reactivity (BHR) phenotypes. Three SNPs in IL18R1 were associated with asthma (0.01131 ... in IL18R1 and asthma....

  7. Replicated Risk Nicotinic Cholinergic Receptor Genes for Nicotine Dependence

    Directory of Open Access Journals (Sweden)

    Lingjun Zuo

    2016-11-01

    Full Text Available It has been hypothesized that the nicotinic acetylcholine receptors (nAChRs play important roles in nicotine dependence (ND and influence the number of cigarettes smoked per day (CPD in smokers. We compiled the associations between nicotinic cholinergic receptor genes (CHRNs and ND/CPD that were replicated across different studies, reviewed the expression of these risk genes in human/mouse brains, and verified their expression using independent samples of both human and mouse brains. The potential functions of the replicated risk variants were examined using cis-eQTL analysis or predicted using a series of bioinformatics analyses. We found replicated and significant associations for ND/CPD at 19 SNPs in six genes in three genomic regions (CHRNB3-A6, CHRNA5-A3-B4 and CHRNA4. These six risk genes are expressed in at least 18 distinct areas of the human/mouse brain, with verification in our independent human and mouse brain samples. The risk variants might influence the transcription, expression and splicing of the risk genes, alter RNA secondary or protein structure. We conclude that the replicated associations between CHRNB3-A6, CHRNA5-A3-B4, CHRNA4 and ND/CPD are very robust. More research is needed to examine how these genetic variants contribute to the risk for ND/CPD.

  8. Replicated Risk Nicotinic Cholinergic Receptor Genes for Nicotine Dependence

    Science.gov (United States)

    Zuo, Lingjun; Garcia-Milian, Rolando; Guo, Xiaoyun; Zhong, Chunlong; Tan, Yunlong; Wang, Zhiren; Wang, Jijun; Wang, Xiaoping; Kang, Longli; Lu, Lu; Chen, Xiangning; Li, Chiang-Shan R.; Luo, Xingguang

    2016-01-01

    It has been hypothesized that the nicotinic acetylcholine receptors (nAChRs) play important roles in nicotine dependence (ND) and influence the number of cigarettes smoked per day (CPD) in smokers. We compiled the associations between nicotinic cholinergic receptor genes (CHRNs) and ND/CPD that were replicated across different studies, reviewed the expression of these risk genes in human/mouse brains, and verified their expression using independent samples of both human and mouse brains. The potential functions of the replicated risk variants were examined using cis-eQTL analysis or predicted using a series of bioinformatics analyses. We found replicated and significant associations for ND/CPD at 19 SNPs in six genes in three genomic regions (CHRNB3-A6, CHRNA5-A3-B4 and CHRNA4). These six risk genes are expressed in at least 18 distinct areas of the human/mouse brain, with verification in our independent human and mouse brain samples. The risk variants might influence the transcription, expression and splicing of the risk genes, alter RNA secondary or protein structure. We conclude that the replicated associations between CHRNB3-A6, CHRNA5-A3-B4, CHRNA4 and ND/CPD are very robust. More research is needed to examine how these genetic variants contribute to the risk for ND/CPD. PMID:27827986

  9. Replicated Risk Nicotinic Cholinergic Receptor Genes for Nicotine Dependence.

    Science.gov (United States)

    Zuo, Lingjun; Garcia-Milian, Rolando; Guo, Xiaoyun; Zhong, Chunlong; Tan, Yunlong; Wang, Zhiren; Wang, Jijun; Wang, Xiaoping; Kang, Longli; Lu, Lu; Chen, Xiangning; Li, Chiang-Shan R; Luo, Xingguang

    2016-11-07

    It has been hypothesized that the nicotinic acetylcholine receptors (nAChRs) play important roles in nicotine dependence (ND) and influence the number of cigarettes smoked per day (CPD) in smokers. We compiled the associations between nicotinic cholinergic receptor genes (CHRNs) and ND/CPD that were replicated across different studies, reviewed the expression of these risk genes in human/mouse brains, and verified their expression using independent samples of both human and mouse brains. The potential functions of the replicated risk variants were examined using cis-eQTL analysis or predicted using a series of bioinformatics analyses. We found replicated and significant associations for ND/CPD at 19 SNPs in six genes in three genomic regions (CHRNB3-A6, CHRNA5-A3-B4 and CHRNA4). These six risk genes are expressed in at least 18 distinct areas of the human/mouse brain, with verification in our independent human and mouse brain samples. The risk variants might influence the transcription, expression and splicing of the risk genes, alter RNA secondary or protein structure. We conclude that the replicated associations between CHRNB3-A6, CHRNA5-A3-B4,CHRNA4 and ND/CPD are very robust. More research is needed to examine how these genetic variants contribute to the risk for ND/CPD.

  10. Expression of androgen receptor target genes in skeletal muscle

    OpenAIRE

    2014-01-01

    We aimed to determine the mechanisms of the anabolic actions of androgens in skeletal muscle by investigating potential androgen receptor (AR)-regulated genes in in vitro and in vivo models. The expression of the myogenic regulatory factor myogenin was significantly decreased in skeletal muscle from testosterone-treated orchidectomized male mice compared to control orchidectomized males, and was increased in muscle from male AR knockout mice that lacked DNA binding activity (ARΔZF2 ) versus w...

  11. [Modifying effect of incorporated 137Cs on the mechanism of adrenergic control of myocardial contraction].

    Science.gov (United States)

    Lobanok, L M; Bulanova, K Ia; Gerasimovich, N V; Sineleva, M V; Miliutin, A A

    1994-01-01

    Incorporated 137Cs (absorbed dose of 0.26 Gy) causes decrease of myocardial's contractile function and inotropic response to beta-adrenagonists effect, isoproterenol-stimulated adenylate cyclase activity and beta-adrenoreceptors affinity. Adrenergic effects, mediated by alpha-adrenergic structures on heart contractile function, on the contrary, become stronger, that is due to the increase of the receptors' density on sarcolemma surface.

  12. Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

    Energy Technology Data Exchange (ETDEWEB)

    Teodorov, E. [Centro de Matemática, Computação e Cognição, Universidade Federal do ABC, São Paulo, SP (Brazil); Ferrari, M.F.R. [Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Fior-Chadi, D.R. [Departamento de Fisiologia, Instituto de Biociências, Universidade de São Paulo, São Paulo, SP (Brazil); Camarini, R. [Departamento de Farmacologia, Instituto de Ciências Biomédicas, Universidade de São Paulo, São Paulo, SP (Brazil); Felício, L.F. [Departamento de Patologia, Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, SP (Brazil)

    2012-06-01

    The periaqueductal gray (PAG) has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc) or 0.9% saline (up to 1 mL/kg) and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05) because a lower percentage of U69593 group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR). A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05) and lactating female rats (P < 0.01), with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in female

  13. Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression

    Directory of Open Access Journals (Sweden)

    E. Teodorov

    2012-10-01

    Full Text Available The periaqueductal gray (PAG has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc or 0.9% saline (up to 1 mL/kg and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05 because a lower percentage of kappa group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR. A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05 and lactating female rats (P < 0.01, with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in

  14. Modulation of adrenal catecholamine secretion by in vivo gene transfer and manipulation of G protein-coupled receptor kinase-2 activity.

    Science.gov (United States)

    Lymperopoulos, Anastasios; Rengo, Giuseppe; Zincarelli, Carmela; Soltys, Stephen; Koch, Walter J

    2008-02-01

    We recently reported that the upregulation of adrenal G protein-coupled receptor kinase-2 (GRK2) causes enhanced catecholamine (CA) secretion by desensitizing sympatho-inhibitory alpha (2)-adrenergic receptors (alpha (2)ARs) of chromaffin cells, and thereby aggravating heart failure (HF). In this study, we sought to develop an efficient and reproducible in vivo adrenal gene transfer method to determine whether manipulation of adrenal GRK2 levels/activity regulates physiological CA secretion in rats. We specifically investigated two different in vivo gene delivery methods: direct injection into the suprarenal glands, and retrograde delivery through the suprarenal veins. We delivered adenoviral (Ad) vectors containing either GRK2 or an inhibitor of GRK2 activity, the beta ARKct. We found both delivery approaches equally effective at supporting robust (>80% of the whole organ) and adrenal-restricted transgene expression, in the cortical region as well as in the medullar region. Additionally, rats with AdGRK2-infected adrenals exhibit enhanced plasma CA levels when compared with control rats (AdGFP-injected adrenals), whereas plasma CA levels after Ad beta ARKct infection were significantly lower. Finally, in isolated chromaffin cells, alpha (2)ARs of AdGRK2-infected cells failed to inhibit CA secretion whereas Ad beta ARKct-infected cells showed normal alpha (2)AR responsiveness. These results not only indicate that in vivo adrenal gene transfer is an effective way of manipulating adrenal gland signalling, but also identify GRK2 as a critically important molecule involved in CA secretion.

  15. Beta-Adrenergic Receptor Population is Up-Regulated by Increased Cyclic Amp Concentration in Chicken Skeletal Muscle Cells in Culture

    Science.gov (United States)

    Young, Ronald B.; Bridge, Kristin Y.; Vaughn, Jeffrey R.

    1999-01-01

    Skeletal muscle hypertrophy is promoted in vivo by administration of beta-drenergic receptor (bAR) agonists. Chicken skeletal muscle cells were treated with 1 (mu)M isoproterenol, a strong bAR agonist, between days 7 and 10 in culture. bAR population increased by approximately 40% during this treatment; however, the ability of the cells to synthesize cyclic AMP (cAMP) was diminished by two-fold. The quantity of myosin heavy chain (MHC) was not affected. To understand further the relationship between intracellular cAMP levels, bAR population, and muscle protein accumulation, intracellular cAMP levels were artificially elevated by treatment with 0-10 uM forskolin for up to three days. The basal concentration of CAMP in forskolin-treated cells increased up to 7-fold in a dose dependent manner. Increasing concentrations of forskolin also led to an increase in bAR population, with a maximum increase of approximately 40-60% at 10 uM forskolin. A maximum increase of 40-50% 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. At 0.2 uM forskolin, intracellular levels of cAMP were higher by approximately 35%, and the (beta)AR population was higher by approximately 30%. Neither the number of muscle nuclei fused into myotubes nor the percentage of nuclei in myotubes were affected by forskolin at any of the concentrations studied.

  16. A novel gene delivery system targeting cells expressing VEGF receptors

    Institute of Scientific and Technical Information of China (English)

    LIJUNMIN; JINGCHULUO; 等

    1999-01-01

    Two ligand oligopeptides GV1 and GV2 were designed according to the putative binding region of VEGF to its receptors.GV1,GV2 and endosome releasing oligopeptide HA20 were conjugated with poly-L-lysine or protamine and the resulting conjugates could interact with DNA in a noncovalent bond to form a complex.Using pSV2-β-galactosidase as a reporter gene,it has been demonstrated that exogenous gene was transferred into bovine aortic arch-derived endothelial cells (ABAE) and human malignant melanoma cell lines (A375) in vitro.In vivo experiments,exogenous gene was transferred into tumor vascular endothelial cells and tumor cells of subcutaneously transplanted human colon cancer LOVO,human malignant melanoma A375 and human hepatoma graft in nude mice.This system could also target gene to intrahepatically transplanted human hepatoma injected via portal vein in nude mice.These results are correlated with the relevant receptors(flt-1,flk-1/KDR) expression on the targeted cells and tissues.

  17. Olfactory receptor gene family evolution in stickleback and medaka fishes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Interaction of olfactory receptor (OR) genes with environmental odors is regarded as the first step of olfaction.In this study,OR genes of two fish,medaka (Oryzias latipes) and stickleback (Gasterosteus aculeatus),were identified and an evolutional analysis was conducted.The selection pressure of different TM regions and complete coding region were compared.Three TM regions (TM4,TM5 and TM6) were found to have higher average Ka/Ks values,which might be partly caused by positive selection as suggested by subsequent positive selection analysis.Further analysis showed that many PTSs overlap,or are adjacent to previously deduced binding sites in mammals.These results support the hypothesis that binding sites of fish OR genes may evolved under positive selection.

  18. Carbon dioxide receptor genes in cotton bollworm Helicoverpa armigera

    Science.gov (United States)

    Xu, Wei; Anderson, Alisha

    2015-04-01

    Carbon dioxide (CO2) is important in insect ecology, eliciting a range of behaviours across different species. Interestingly, the numbers of CO2 gustatory receptors (GRs) vary among insect species. In the model organism Drosophila melanogaster, two GRs (DmelGR21a and DmelGR63a) have been shown to detect CO2. In the butterfly, moth, beetle and mosquito species studied so far, three CO2 GR genes have been identified, while in tsetse flies, four CO2 GR genes have been identified. In other species including honeybees, pea aphids, ants, locusts and wasps, no CO2 GR genes have been identified from the genome. These genomic differences may suggest different mechanisms for CO2 detection exist in different insects but, with the exception of Drosophila and mosquitoes, limited attention has been paid to the CO2 GRs in insects. Here, we cloned three putative CO2 GR genes from the cotton bollworm Helicoverpa armigera and performed phylogenetic and expression analysis. All three H. armigera CO2 GRs (HarmGR1, HarmGR2 and HarmGR3) are specifically expressed in labial palps, the CO2-sensing tissue of this moth. HarmGR3 is significantly activated by NaHCO3 when expressed in insect Sf9 cells but HarmGR1 and HarmGR2 are not. This is the first report characterizing the function of lepidopteran CO2 receptors, which contributes to our general understanding of the molecular mechanisms of insect CO2 gustatory receptors.

  19. Antagonism of apomorphine-enhanced startle by alpha 1-adrenergic antagonists.

    Science.gov (United States)

    Davis, M; Kehne, J H; Commissaris, R L

    1985-02-05

    The present study investigated the possible involvement of central noradrenergic neurons in mediating the excitatory effect of the dopamine agonist apomorphine on the acoustic startle response in rats. Experiment 1 assessed the effects of intraperitoneal (i.p.) administration of adrenergic antagonists on apomorphine-enhanced startle. The excitation of startle produced by apomorphine (1.0-3.0 mg/kg i.p.) was blocked by the alpha 1-adrenergic antagonists prazosin (0.03-1.0 mg/kg) and WB-4101 (1.0 mg/kg). Prazosin was very potent in this regard, having an ED50 of 0.03 mg/kg. Blockade of beta-adrenergic receptors with propranolol (20 mg/kg) or blockade of peripheral alpha-adrenergic receptors with phentolamine (10 mg/kg) failed to alter the effect of apomorphine. Prazosin did not block the enhancement of startle produced by other drugs (5-methoxy-N,N-dimethyltryptamine, strychnine), nor did it alter the entry of apomorphine into the brain. The alpha 1-adrenergic antagonists piperoxane (0.03 mg/kg), yohimbine (0.03 mg/kg) or RX781094 (0.07 mg/kg) markedly potentiated apomorphine excitation. These data indicated that specific blockade of central alpha 1-adrenergic receptors prevents apomorphine-enhanced startle. In contrast to the effects of alpha 1-adrenergic antagonists, Experiment 2 found that other drugs that produce an acute (clonidine, 0.040 mg/kg) or chronic (intraventricular 6-hydroxydopamine, 2 X 200 micrograms; DSP4, 50 mg/kg i.p.) disruption of noradrenergic transmission failed to affect apomorphine excitation. Thus, the ability of alpha 1-adrenergic antagonists to block apomorphine's excitation of startle cannot be explained by a simple dopamine-norepinephrine interaction. Alternative hypothesis are discussed.

  20. Two polymorphisms in the glucocorticoid receptor gene directly affect glucocorticoid-regulated gene expression.

    NARCIS (Netherlands)

    H. Russcher (Henk); P. Smit (Pauline); E.L.T. van den Akker (Erica); E.F.C. van Rossum (Liesbeth); A.O. Brinkmann (Albert); F.H. de Jong (Frank); S.W.J. Lamberts (Steven); J.W. Koper (Jan)

    2005-01-01

    textabstractCONTEXT: Interindividual variation in glucocorticoid (GC)-sensitivity can be partly explained by polymorphisms in the GC receptor (GR) gene. The ER22/23EK and N363S polymorphisms have been described to be associated with lower and higher GC sensitivity, respectively. OBJECTIVE AND DESIGN

  1. Human alpha 2-adrenergic receptor subtype distribution: widespread and subtype-selective expression of alpha 2C10, alpha 2C4, and alpha 2C2 mRNA in multiple tissues.

    Science.gov (United States)

    Eason, M G; Liggett, S B

    1993-07-01

    At present, molecular cloning and pharmacological studies have delineated three human alpha 2-adrenergic receptor (alpha 2AR) subtypes, alpha 2C10, alpha 2C4, and alpha 2C2. Assignment of the alpha 2AR subtypes to specific functions has been limited by an unclear definition of tissue alpha 2AR expression outside of the central nervous system. It has been suggested that alpha 2C4 expression is confined to the brain, that alpha 2C2 expression is only in the liver and kidney, and that there is nearly ubiquitous expression of alpha 2C10. However, this is based on studies of a limited number of rat tissues or on studies using non-species-specific approaches. Therefore, to define alpha 2C10, alpha 2C4, and alpha 2C2 tissue expression, we used reverse transcription of total RNA isolated from 20 human tissues, followed by amplification of alpha 2AR cDNA using the polymerase chain reaction. This technique provided two advantages: high sensitivity and, with the use of subtype-specific oligonucleotide primers and probes, differentiation between the alpha 2AR subtypes. The tissues studied were aorta, vena cava, heart (epicardium and endocardium), lung, skeletal muscle, liver, pancreas (head and tail), fat (perinephric and subcutaneous), kidney (cortex and medulla), prostate, stomach, ileum, jejunum, colon, adrenal gland, and spleen. We found that the majority of these tissues expressed alpha 2C10, with the exceptions being the head of the pancreas, subcutaneous fat, colon, and spleen. In marked distinction to other studies, however, we found a prolific expression of the alpha 2C4 and alpha 2C2 subtypes. Expression of alpha 2C4 was found in all tissues with the exception of liver, fat, stomach, and colon, and a virtually ubiquitous expression of alpha 2C2 was found, with the exception of epicardium. Of all tissues studied, only colon and subcutaneous fat expressed a single alpha 2AR subtype, which was alpha 2C2. Thus, the alpha 2AR subtypes do not have a confined expression but

  2. Omega-3 fatty acid deficient male rats exhibit abnormal behavioral activation in the forced swim test following chronic fluoxetine treatment: association with altered 5-HT1A and alpha2A adrenergic receptor expression.

    Science.gov (United States)

    Able, Jessica A; Liu, Yanhong; Jandacek, Ronald; Rider, Therese; Tso, Patrick; McNamara, Robert K

    2014-03-01

    Omega-3 fatty acid deficiency during development leads to enduing alterations in central monoamine neurotransmission in rat brain. Here we investigated the effects of omega-3 fatty acid deficiency on behavioral and neurochemical responses to chronic fluoxetine (FLX) treatment. Male rats were fed diets with (CON, n = 34) or without (DEF, n = 30) the omega-3 fatty acid precursor alpha-linolenic acid (ALA) during peri-adolescent development (P21-P90). A subset of CON (n = 14) and DEF (n = 12) rats were administered FLX (10 mg/kg/d) through their drinking water for 30 d beginning on P60. The forced swimming test (FST) was initiated on P90, and regional brain mRNA markers of serotonin and noradrenaline neurotransmission were determined. Dietary ALA depletion led to significant reductions in frontal cortex docosahexaenoic acid (DHA, 22:6n-3) composition in DEF (-26%, p = 0.0001) and DEF + FLX (-32%, p = 0.0001) rats. Plasma FLX and norfluoxetine concentrations did not different between FLX-treated DEF and CON rats. During the 15-min FST pretest, DEF + FLX rats exhibited significantly greater climbing behavior compared with CON + FLX rats. During the 5-min test trial, FLX treatment reduced immobility and increased swimming in CON and DEF rats, and only DEF + FLX rats exhibited significant elevations in climbing behavior. DEF + FLX rats exhibited greater midbrain, and lower frontal cortex, 5-HT1A mRNA expression compared with all groups including CON + FLX rats. DEF + FLX rats also exhibited greater midbrain alpha2A adrenergic receptor mRNA expression which was positively correlated with climbing behavior in the FST. These preclinical data demonstrate that low omega-3 fatty acid status leads to abnormal behavioral and neurochemical responses to chronic FLX treatment in male rats.

  3. Diverse growth hormone receptor gene mutations in Laron syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Berg, M.A.; Francke, U. (Stanford Univ. School of Medicine, CA (United States)); Gracia, R.; Rosenbloom, A.; Toledo, S.P.A. (Univ. Autonoma, Madrid (Spain)); Chernausek, S. (Children' s Hospital Medical Center, Cincinnati, OH (United States)); Guevara-Aguirre, J. (Institute of Endocrinology, Metabolism, and Reproduction, Quito (Ecuador)); Hopp, M. (Univ. of Witwatersrand, Johannesburg (South Africa)); Rosenbloom, A.; Argente, J. (Univ. of Florida, Gainesville (United States)); Toledo, S.P.A. (Univ. of Sao Paulo (Brazil))

    1993-05-01

    To better understand the molecular genetic basis and genetic epidemiology of Laron syndrome (growth-hormone insensitivity syndrome), the authors analysed the growth-hormone receptor (GHR) genes of seven unrelated affected individuals from the United States, South America, Europe, and Africa. They amplified all nine GHR gene exons and splice junctions from these individuals by PCR and screened the products for mutations by using denaturing gradient gel electrophoresis (DGGE). They identified a single GHR gene fragment with abnormal DGGE results for each affected individual, sequenced this fragment, and, in each case, identified a mutation likely to cause Laron syndrome, including two nonsense mutations (R43X and R217X), two splice-junction mutations, (189-1 G to T and 71+1 G to A), and two frameshift mutations (46 del TT and 230 del TA or AT). Only one of these mutations, R43X, has been previously reported. Using haplotype analysis, they determined that this mutation, which involves a CpG dinucleotide hot spot, likely arose as a separate event in this case, relative to the two prior reports of R43X. Aside from R43X, the mutations identified are unique to patients from particular geographic regions. Ten GHR gene mutations have now been described in this disorder. The authors conclude that Laron syndrome is caused by diverse GHR gene mutations, including deletions, RNA processing defects, translational stop codons, and missense codons. All the identified mutations involve the extracellular domain of the receptor, and most are unique to particular families or geographic areas. 35 refs., 3 figs., 1 tab.

  4. Genomic organization, annotation, and ligand-receptor inferences of chicken chemokines and chemokine receptor genes based on comparative genomics

    Directory of Open Access Journals (Sweden)

    Sze Sing-Hoi

    2005-03-01

    Full Text Available Abstract Background Chemokines and their receptors play important roles in host defense, organogenesis, hematopoiesis, and neuronal communication. Forty-two chemokines and 19 cognate receptors have been found in the human genome. Prior to this report, only 11 chicken chemokines and 7 receptors had been reported. The objectives of this study were to systematically identify chicken chemokines and their cognate receptor genes in the chicken genome and to annotate these genes and ligand-receptor binding by a comparative genomics approach. Results Twenty-three chemokine and 14 chemokine receptor genes were identified in the chicken genome. All of the chicken chemokines contained a conserved CC, CXC, CX3C, or XC motif, whereas all the chemokine receptors had seven conserved transmembrane helices, four extracellular domains with a conserved cysteine, and a conserved DRYLAIV sequence in the second intracellular domain. The number of coding exons in these genes and the syntenies are highly conserved between human, mouse, and chicken although the amino acid sequence homologies are generally low between mammalian and chicken chemokines. Chicken genes were named with the systematic nomenclature used in humans and mice based on phylogeny, synteny, and sequence homology. Conclusion The independent nomenclature of chicken chemokines and chemokine receptors suggests that the chicken may have ligand-receptor pairings similar to mammals. All identified chicken chemokines and their cognate receptors were identified in the chicken genome except CCR9, whose ligand was not identified in this study. The organization of these genes suggests that there were a substantial number of these genes present before divergence between aves and mammals and more gene duplications of CC, CXC, CCR, and CXCR subfamilies in mammals than in aves after the divergence.

  5. Catecholamine-related gene expression in blood correlates with tic severity in tourette syndrome

    NARCIS (Netherlands)

    Gunther, Joan; Tian, Yingfang; Stamova, Boryana; Lit, Lisa; Corbett, Blythe; Ander, Brad; Zhan, Xinhua; Jickling, Glen; Bos-Veneman, Netty; Liu, Da; Hoekstra, Pieter; Sharp, Frank

    2012-01-01

    Tourette syndrome (TS) is a heritable disorder characterized by tics that are decreased in some patients by treatment with alpha adrenergic agonists and dopamine receptor blockers. Thus, this study examines the relationship between catecholamine gene expression in blood and tic severity. TS diagnosi

  6. A Novel Gene Delivery System Targeting Urokinase Receptor

    Institute of Scientific and Technical Information of China (English)

    Xing-Hui SUN; Li TAN; Chun-Yang LI; Chang TONG; Jin FAN; Ping LI; Yun-Song ZHU

    2004-01-01

    Recombinant proteins that combine different functions required for cell targeting and intracellular delivery of DNA present an attractive approach for the development of nonviral gene delivery vectors. Here, we described a novel protein termed ATF-lys10 which facilitated cell-specific gene transfer via receptor-mediated endocytosis. ATF-lys 10 was composed of the amino-terminal fragment of urokinase and ten lysines at the carboxyl terminus. Bacterially expressed ATF-lys 10 protein existed in soluble form, and had antigenicity of human urokinase. Purified ATF-lys 10 specifically bound to uPAR-expressing cells and formed protein-DNA complexes with plasmid pGL3-control. After neutralization of excess negative charge with poly-L-lysine, these complexes served as a specific gene delivery vector for uPAR-expressing cells. Lysosomotropic compounds, such as chloroquine, drastically increased the ATF-lysl0 mediated gene delivery efficiency. Our results suggest that the recombinant protein ATF-lys 10 with the properties of DNA binding and tumor cell targeting represents a promising method for gene transfer and expression in tumor cells.

  7. Chicken interferons, their receptors and interferon-stimulated genes.

    Science.gov (United States)

    Goossens, Kate E; Ward, Alister C; Lowenthal, John W; Bean, Andrew G D

    2013-11-01

    The prevalence of pathogenic viruses is a serious issue as they pose a constant threat to both the poultry industry and to human health. To prevent these viral infections an understanding of the host-virus response is critical, especially for the development of novel therapeutics. One approach in the control of viral infections would be to boost the immune response through administration of cytokines, such as interferons. However, the innate immune response in chickens is poorly characterised, particularly concerning the interferon pathway. This review will provide an overview of our current understanding of the interferon system of chickens, including their cognate receptors and known interferon-stimulated gene products.

  8. Evolution of the chicken Toll-like receptor gene family: A story of gene gain and gene loss

    Directory of Open Access Journals (Sweden)

    Paton Ian R

    2008-02-01

    Full Text Available Abstract Background Toll-like receptors (TLRs perform a vital role in disease resistance through their recognition of pathogen associated molecular patterns (PAMPs. Recent advances in genomics allow comparison of TLR genes within and between many species. This study takes advantage of the recently sequenced chicken genome to determine the complete chicken TLR repertoire and place it in context of vertebrate genomic evolution. Results The chicken TLR repertoire consists of ten genes. Phylogenetic analyses show that six of these genes have orthologs in mammals and fish, while one is only shared by fish and three appear to be unique to birds. Furthermore the phylogeny shows that TLR1-like genes arose independently in fish, birds and mammals from an ancestral gene also shared by TLR6 and TLR10. All other TLRs were already present prior to the divergence of major vertebrate lineages 550 Mya (million years ago and have since been lost in certain lineages. Phylogenetic analysis shows the absence of TLRs 8 and 9 in chicken to be the result of gene loss. The notable exception to the tendency of gene loss in TLR evolution is found in chicken TLRs 1 and 2, each of which underwent gene duplication about 147 and 65 Mya, respectively. Conclusion Comparative phylogenetic analysis of vertebrate TLR genes provides insight into their patterns and processes of gene evolution, with examples of both gene gain and gene loss. In addition, these comparisons clarify the nomenclature of TLR genes in vertebrates.

  9. Analysis of adrenergic regulation of melatonin synthesis in Siberian hamster pineal emphasizes the role of HIOMT.

    Science.gov (United States)

    Ceinos, R M; Chansard, M; Revel, F; Calgari, C; Míguez, J M; Simonneaux, V

    2004-01-01

    Seasonal variations of environmental factors are translated into annual fluctuations in synthesis and release of melatonin, which in turn acts as a neuroendocrine messenger for the synchronization of annual functions. So far, most studies performed to understand the regulation of melatonin synthesis have used the non seasonal laboratory rat. It was demonstrated that nocturnal melatonin synthesis depends on alpha- and beta-adrenergic activation of the enzyme arylalkylamine N-acetyltransferase (AA-NAT). In this study, we investigated the mechanisms of melatonin synthesis in the Siberian hamster, a seasonal species with marked photoperiodic variation in melatonin peak duration and amplitude. A beta-adrenergic receptor agonist alone markedly stimulated AA-NAT activity and melatonin synthesis and release. An alpha-adrenergic receptor agonist, while having no effect per se, potentiated the beta-adrenergic stimulation of AA-NAT activity both in vitro and in vivo. Strikingly, the potentiation of AA-NAT activity did not result in a potentiation of melatonin synthesis, suggesting that the rate of melatonin production is limited downstream in the metabolic pathway, most probably at the level of hydroxyindole-O-methyltransferase (HIOMT). HIOMT presented a constitutively high activity that was not acutely (within hours) stimulated by beta-adrenergic agonist, but was rather up-regulated by chronic application of the agonist. This long-term beta-adrenergic regulation may explain the reported large photoperiodic variation of HIOMT activity that drives the photoperiodic variation in melatonin peak.

  10. Adrenergic effects on secretion of amylase from the rat salivary glands

    DEFF Research Database (Denmark)

    Poulsen, Steen Seier; Nexø, Ebba

    1988-01-01

    The present study was undertaken to investigate the effect of adrenergic agents on secretion of amylase from the salivary glands in vivo. Saliva was collected from the distal oesophagus in conscious rats. Adrenaline increased the concentration of amylase in saliva and serum significantly....... The result of infusion of alpha- and beta-adrenergic antagonists as well as noradrenaline and isoproterenol showed that secretion of salivary amylase is predominantly mediated by stimulation of beta-adrenergic receptors, especially of the beta 1-subtype. Investigation of the isoenzyme pattern in saliva......, pancreatic juice and serum demonstrated that the major component in serum is salivary amylase. This study has shown that beta-adrenergic agents stimulate secretion of amylase from the salivary glands in rats. Though the secretion is mainly exocrine small amounts of amylase is found in serum, which seems...

  11. A reference gene set for chemosensory receptor genes of Manduca sexta.

    Science.gov (United States)

    Koenig, Christopher; Hirsh, Ariana; Bucks, Sascha; Klinner, Christian; Vogel, Heiko; Shukla, Aditi; Mansfield, Jennifer H; Morton, Brian; Hansson, Bill S; Grosse-Wilde, Ewald

    2015-11-01

    The order of Lepidoptera has historically been crucial for chemosensory research, with many important advances coming from the analysis of species like Bombyx mori or the tobacco hornworm, Manduca sexta. Specifically M. sexta has long been a major model species in the field, especially regarding the importance of olfaction in an ecological context, mainly the interaction with its host plants. In recent years transcriptomic data has led to the discovery of members of all major chemosensory receptor families in the species, but the data was fragmentary and incomplete. Here we present the analysis of the newly available high-quality genome data for the species, supplemented by additional transcriptome data to generate a high quality reference gene set for the three major chemosensory receptor gene families, the gustatory (GR), olfactory (OR) and antennal ionotropic receptors (IR). Coupled with gene expression analysis our approach allows association of specific receptor types and behaviors, like pheromone and host detection. The dataset will provide valuable support for future analysis of these essential chemosensory modalities in this species and in Lepidoptera in general.

  12. Update of the androgen receptor gene mutations database.

    Science.gov (United States)

    Gottlieb, B; Beitel, L K; Lumbroso, R; Pinsky, L; Trifiro, M

    1999-01-01

    The current version of the androgen receptor (AR) gene mutations database is described. The total number of reported mutations has risen from 309 to 374 during the past year. We have expanded the database by adding information on AR-interacting proteins; and we have improved the database by identifying those mutation entries that have been updated. Mutations of unknown significance have now been reported in both the 5' and 3' untranslated regions of the AR gene, and in individuals who are somatic mosaics constitutionally. In addition, single nucleotide polymorphisms, including silent mutations, have been discovered in normal individuals and in individuals with male infertility. A mutation hotspot associated with prostatic cancer has been identified in exon 5. The database is available on the internet (http://www.mcgill.ca/androgendb/), from EMBL-European Bioinformatics Institute (ftp.ebi.ac.uk/pub/databases/androgen), or as a Macintosh FilemakerPro or Word file (MC33@musica.mcgill.ca).

  13. Oxytocin receptor and vasopressin receptor 1a genes are respectively associated with emotional and cognitive empathy.

    Science.gov (United States)

    Uzefovsky, F; Shalev, I; Israel, S; Edelm