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Sample records for altered gaba levels

  1. mRNA and Protein Levels for GABA[subscript A][alpha]4, [alpha]5, [beta]1 and GABA[subscript B]R1 Receptors are Altered in Brains from Subjects with Autism

    Science.gov (United States)

    Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rooney, Robert J.; Patel, Diven H.; Thuras, Paul D.

    2010-01-01

    We have shown altered expression of gamma-aminobutyric acid A (GABA[subscript A]) and gamma-aminobutyric acid B (GABA[subscript B]) receptors in the brains of subjects with autism. In the current study, we sought to verify our western blotting data for GABBR1 via qRT-PCR and to expand our previous work to measure mRNA and protein levels of 3…

  2. Stress-restress evokes sustained iNOS activity and altered GABA levels and NMDA receptors in rat hippocampus

    DEFF Research Database (Denmark)

    Harvey, Brian H; Oosthuizen, Frasia; Brand, Linda;

    2004-01-01

    RATIONALE: Stress-related glucocorticoid and glutamate release have been implicated in hippocampal atrophy evident in patients with post-traumatic stress disorder (PTSD). Glutamatergic mechanisms activate nitric oxide synthase (NOS), while gamma-amino-butyric acid (GABA) may inhibit both...... glutamatergic and nitrergic transmission. Animal studies support a role for NOS in stress. OBJECTIVES: We have studied the role of NOS and glucocorticoids, as well as inhibitory and excitatory transmitters, in a putative animal model of PTSD that emphasizes repeated trauma. METHODS: Hippocampal NOS activity, N......-methyl-D-aspartate (NMDA) receptor binding characteristics and GABA levels were studied in Sprague-Dawley rats 21 days after exposure to a stress-restress paradigm, using radiometric analysis, radioligand studies and high-performance liquid chromatography (HPLC) analysis with electrochemical detection, respectively...

  3. Setting GABA levels: GABA transporters modulation by adenosine receptors

    OpenAIRE

    Ferreira, Ana Sofia Cristóvão,1983-

    2012-01-01

    O ácido gama-aminobutírico (GABA) é o principal neurotransmissor inibitório do Sistema Nervoso Central (SNC). Uma vez na sinapse o GABA é rapidamente recaptado através de transportadores específicos expressos pelos neurónios mas também pelas células da glia, que envolvem a sinapse. A rápida recaptação de GABA pelos transportadores permite um controlo adequado dos níveis de GABA na sinapse, o que é fundamental para a limitação temporal e espacial da transmissão inibitór...

  4. Regulation of Local Ambient GABA Levels via Transporter-Mediated GABA Import and Export for Subliminal Learning.

    Science.gov (United States)

    Hoshino, Osamu

    2015-06-01

    Perception of supraliminal stimuli might in general be reflected in bursts of action potentials (spikes), and their memory traces could be formed through spike-timing-dependent plasticity (STDP). Memory traces for subliminal stimuli might be formed in a different manner, because subliminal stimulation evokes a fraction (but not a burst) of spikes. Simulations of a cortical neural network model showed that a subliminal stimulus that was too brief (10 msec) to perceive transiently (more than about 500 msec) depolarized stimulus-relevant principal cells and hyperpolarized stimulus-irrelevant principal cells in a subthreshold manner. This led to a small increase or decrease in ongoing-spontaneous spiking activity frequency (less than 1 Hz). Synaptic modification based on STDP during this period effectively enhanced relevant synaptic weights, by which subliminal learning was improved. GABA transporters on GABAergic interneurons modulated local levels of ambient GABA. Ambient GABA molecules acted on extrasynaptic receptors, provided principal cells with tonic inhibitory currents, and contributed to achieving the subthreshold neuronal state. We suggest that ongoing-spontaneous synaptic alteration through STDP following subliminal stimulation may be a possible neuronal mechanism for leaving its memory trace in cortical circuitry. Regulation of local ambient GABA levels by transporter-mediated GABA import and export may be crucial for subliminal learning. PMID:25774546

  5. GABA level, gamma oscillation, and working memory performance in schizophrenia

    Directory of Open Access Journals (Sweden)

    Chi-Ming A. Chen

    2014-01-01

    Full Text Available A relationship between working memory impairment, disordered neuronal oscillations, and abnormal prefrontal GABA function has been hypothesized in schizophrenia; however, in vivo GABA measurements and gamma band neural synchrony have not yet been compared in schizophrenia. This case–control pilot study (N = 24 compared baseline and working memory task-induced neuronal oscillations acquired with high-density electroencephalograms (EEGs to GABA levels measured in vivo with magnetic resonance spectroscopy. Working memory performance, baseline GABA level in the left dorsolateral prefrontal cortex (DLPFC, and measures of gamma oscillations from EEGs at baseline and during a working memory task were obtained. A major limitation of this study is a relatively small sample size for several analyses due to the integration of diverse methodologies and participant compliance. Working memory performance was significantly lower for patients than for controls. During the working memory task, patients (n = 7 had significantly lower amplitudes in gamma oscillations than controls (n = 9. However, both at rest and across working memory stages, there were significant correlations between gamma oscillation amplitude and left DLPFC GABA level. Peak gamma frequency during the encoding stage of the working memory task (n = 16 significantly correlated with GABA level and working memory performance. Despite gamma band amplitude deficits in patients across working memory stages, both baseline and working memory-induced gamma oscillations showed strong dependence on baseline GABA levels in patients and controls. These findings suggest a critical role for GABA function in gamma band oscillations, even under conditions of system and cognitive impairments as seen in schizophrenia.

  6. [Pharmacological influences on the brain level and transport of GABA. II) Effect of various psychoactive drugs on brain level and uptake of GABA].

    Science.gov (United States)

    Gabana, M A; Varotto, M; Saladini, M; Zanchin, G; Battistin, L

    1981-04-30

    The effects of some psychoactive drugs on the level and uptake of GABA in the mouse brain was studied using well standardized procedures, mainely the silica-gel cromatography for determining the GABA content and the brain slices for measuring GABA uptake. It was found that levomepromazine, sulpiride, haloperidol and amytryptiline were without effects on the cerebral level of GABA; it was also found that these drugs do not influence the rates of uptake of GABA by mouse brain slices. Such results do indicate that the psychoactive drugs studied are without effects on the level and uptake of GABA in the brain. PMID:7272066

  7. In vivo neurochemical evidence that newly synthesised GABA activates GABA(B), but not GABA(A), receptors on dopaminergic nerve endings in the nucleus accumbens of freely moving rats

    NARCIS (Netherlands)

    Saigusa, T.; Aono, Y.; Sekino, R.; Uchida, T.; Takada, K.; Oi, Y.; Koshikawa, N.; Cools, A.R.

    2012-01-01

    GABA released from accumbal GABAergic interneurons plays an inhibitory role in the regulation of dopamine efflux through GABA(B) and GABA(A) receptors located on accumbal dopaminergic nerve endings. The cytosolic newly synthesised GABA alters vesicular GABA levels and, accordingly, the amount of GAB

  8. Antiepileptic activity of lobeline isolated from the leaf of Lobelia nicotianaefolia and its effect on brain GABA level in mice

    Institute of Scientific and Technical Information of China (English)

    Abrar M Tamboli; Rukhsana A Rub; Pinaki Ghosh; SL Bodhankar

    2012-01-01

    Objective:To investigate the anticonvulsant activity of the lobeline isolated from the Lobelia nicotianaefolia in chemoconvulsant-induced seizures and its biochemical mechanism by investigating relationship between seizure activities and altered gamma amino butyric acid (GABA) in brain of mice in Pentylenetetrazol (PTZ) seizure models. Methods:The anticonvulsant activity of the isolated lobeline (5, 10, 20 and 30 mg/kg, i.p.) was investigated in PTZ and strychnine induced seizures in mice and the effect of isolated lobeline on brain GABA level in seizures induced by PTZ. Diazepam was used as reference anticonvulsant drugs for comparison. Results:Isolated lobeline (10, 20 and 30 mg/kg, i.p.) significantly delayed and antagonized (P<0.050–0.001) the onset of PTZ-induced seizures. It also antagonized strychnine induced seizures. The mortality was also prevented in the test group of animals. In biochemical evaluation, isolated lobeline (5, 10 and 20 mg/kg, i.p.) significantly increased the brain GABA level. And at dose of 30 mg/kg GABA level showed slight decrease in PTZ model. Conclusions:In our findings, isolated lobeline (20mg/kg) exhibited potent anticonvulsant activity against PTZ induced seizures. Also a biochemical evaluation suggested significant increase in barain GABA level at 20 mg/kg i.p. of isolated lobeline. Hence, we may propose that lobeline reduces epileptic seizures by enhancing the GABA release supporting the GABAergic mechanism.

  9. Temporal development of GABA agonist induced alterations in ultrastructure and GABA receptor expression in cultured cerebellar granule cells

    DEFF Research Database (Denmark)

    Hansen, G H; Belhage, B; Schousboe, A;

    1987-01-01

    The temporal development of the effect of THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) on the ultrastructure composition and GABA receptor expression in cerebellar granule cells was investigated by quantitative electron microscopy (morphometric analysis) and GABA binding assays. It was...... exposed to THIP (150 microM) for 3 hr low affinity GABA receptors were induced. These findings show that the effect of THIP on the ultrastructure composition and GABA receptor expression in cultured cerebellar granule cells may be interrelated and moreover it is likely that the turn-over of GABA receptors...

  10. An autocrine role for pituitary GABA: Activation of GABA-B receptors and regulation of growth hormone levels

    OpenAIRE

    Gamel-Didelon, Katia; Corsi, C.; Pepeu, G.; Jung, H.; Gratzl, M; Mayerhofer, Artur

    2002-01-01

    There is increasing evidence suggesting that the neurotransmitter gamma-aminobutyric acid (GABA) is a local factor involved in the regulation of endocrine organs. Examples of such functions are documented in the pancreas, but recent results suggest that GABA may act in a similar way in the pituitary, in which GABA receptors are expressed and pituitary growth hormone (GH) cells provide a source of GABA. We hypothesised that GABA secreted in somatotropes may act as an autoregulatory signaling m...

  11. Removal of GABA(A receptor γ2 subunits from parvalbumin neurons causes wide-ranging behavioral alterations.

    Directory of Open Access Journals (Sweden)

    Elli Leppä

    Full Text Available We investigated the behavioral significance of fast synaptic inhibition by αβγ2-type GABA(A receptors on parvalbumin (Pv cells. The GABA(A receptor γ2 subunit gene was selectively inactivated in Pv-positive neurons by Cre/loxP recombination. The resulting Pv-Δγ2 mice were relatively healthy in the first postnatal weeks; but then as Cre started to be expressed, the mice progressively developed wide-ranging phenotypic alterations including low body weight, motor deficits and tremor, decreased anxiety levels, decreased pain sensitivity and deficient prepulse inhibition of the acoustic startle reflex and impaired spatial learning. Nevertheless, the deletion was not lethal, and mice did not show increased mortality even after one year. Autoradiography with t-butylbicyclophosphoro[(35S]thionate suggested an increased amount of GABA(A receptors with only α and β subunits in central nervous system regions that contained high levels of parvalbumin neurons. Using BAC-transgenesis, we reduced some of the Pv-Δγ2 phenotype by selectively re-expressing the wild-type γ2 subunit back into some Pv cells (reticular thalamic neurons and cerebellar Pv-positive neurons. This produced less severe impairments of motor skills and spatial learning compared with Pv-Δγ2 mice, but all other deficits remained. Our results reveal the widespread significance of fast GABAergic inhibition onto Pv-positive neurons for diverse behavioral modalities, such as motor coordination, sensorimotor integration, emotional behavior and nociception.

  12. Brain GABA levels across psychiatric disorders: A systematic literature review and meta-analysis of (1) H-MRS studies.

    Science.gov (United States)

    Schür, Remmelt R; Draisma, Luc W R; Wijnen, Jannie P; Boks, Marco P; Koevoets, Martijn G J C; Joëls, Marian; Klomp, Dennis W; Kahn, René S; Vinkers, Christiaan H

    2016-09-01

    The inhibitory gamma-aminobutyric acid (GABA) system is involved in the etiology of most psychiatric disorders, including schizophrenia, autism spectrum disorder (ASD) and major depressive disorder (MDD). It is therefore not surprising that proton magnetic resonance spectroscopy ((1) H-MRS) is increasingly used to investigate in vivo brain GABA levels. However, integration of the evidence for altered in vivo GABA levels across psychiatric disorders is lacking. We therefore systematically searched the clinical (1) H-MRS literature and performed a meta-analysis. A total of 40 studies (N = 1,591) in seven different psychiatric disorders were included in the meta-analysis: MDD (N = 437), schizophrenia (N = 517), ASD (N = 150), bipolar disorder (N = 129), panic disorder (N = 81), posttraumatic stress disorder (PTSD) (N = 104), and attention deficit/hyperactivity disorder (ADHD) (N = 173). Brain GABA levels were lower in ASD (standardized mean difference [SMD] = -0.74, P = 0.001) and in depressed MDD patients (SMD = -0.52, P = 0.005), but not in remitted MDD patients (SMD = -0.24, P = 0.310) compared with controls. In schizophrenia this finding did not reach statistical significance (SMD = -0.23, P = 0.089). No significant differences in GABA levels were found in bipolar disorder, panic disorder, PTSD, and ADHD compared with controls. In conclusion, this meta-analysis provided evidence for lower brain GABA levels in ASD and in depressed (but not remitted) MDD patients compared with healthy controls. Findings in schizophrenia were more equivocal. Even though future (1) H-MRS studies could greatly benefit from a longitudinal design and consensus on the preferred analytical approach, it is apparent that (1) H-MRS studies have great potential in advancing our understanding of the role of the GABA system in the pathogenesis of psychiatric disorders. Hum Brain Mapp 37:3337-3352, 2016. © 2016 Wiley Periodicals

  13. GABA-A and NMDA receptor expression is altered in the caudate but not the putamen of the postmortem brains of alcoholics.

    Directory of Open Access Journals (Sweden)

    Igor Bazov

    2014-12-01

    Full Text Available Chronic consumption of alcohol by humans has been shown to lead to impairment of executive and cognitive functions. Here we have studied the changes that take place in the dorsal striatum in post-mortem brains of alcoholics and normal controls. The results show a significant change in the expression of both the excitatory ionotropic glutamate receptor and the inhibitory GABA-A receptor subunit genes in the caudate but not the putamen of the striatum. The mRNA levels in the caudate encoding the glutamate receptor subunit GluN2A and the GABA-A receptor subunits δ, ε and ρ2 were significantly decreased whereas the GluD1, GluD2 and the GABA-A γ1 mRNA levels were significantly increased in the alcoholics as compared to controls. Interestingly in controls, 11 glutamate and 5 GABA-A receptor genes were more prominently (fold-increase varied from 1.24 to 2.91 expressed in the caudate than the putamen. We have previously shown in post-mortem samples from alcoholics that the expression level of glutamate and GABA-A receptor genes in the dorsal-lateral prefrontal cortex is similar to that of normal controls (Jin et al., 2011a;Jin et al., 2014b. This is in contrast to the present study. As the caudate is vital for automatic thinking, the results indicate that the balance between voluntary and automatic control of behaviours is altered in alcoholics. Our results suggest that there may be diminished executive control on goal-directed alcohol-seeking behaviour and, rather, a shift to greater striatal control over behaviours that may be critical in the progress of becoming an alcoholic.

  14. Oxytocin regulates changes of extracellular glutamate and GABA levels induced by methamphetamine in the mouse brain.

    Science.gov (United States)

    Qi, Jia; Han, Wen-Yan; Yang, Jing-Yu; Wang, Li-Hui; Dong, Ying-Xu; Wang, Fang; Song, Ming; Wu, Chun-Fu

    2012-07-01

    Oxytocin (OT), a neurohypophyseal neuropeptide, affects adaptive processes of the central nervous system. In the present study, we investigated the effects of OT on extracellular levels of glutamate (Glu) and γ-aminobutyric acid (GABA) induced by methamphetamine (MAP) in the medial prefrontal cortex (mPFC) and dorsal hippocampus (DHC) of freely moving mice, using in vivo microdialysis coupled to high-performance liquid chromatography and fluorescence detection. The results showed that OT had no effect on basal Glu levels, but attenuated MAP-induced Glu increase in the mPFC and decrease in the DHC. OT increased the basal levels of extracellular GABA in mPFC and DHC of mice, and inhibited the MAP-induced GABA decrease in DHC. Western blot results indicated that OT significantly inhibited the increased glutamatergic receptor (NR1 subunit) levels in the PFC after acute MAP administration, whereas OT further enhanced the elevated levels of glutamatergic transporter (GLT1) induced by MAP in the hippocampus of mice. Atosiban, a selective inhibitor of OT receptor, antagonized the effects of OT. The results provided the first neurochemical evidence that OT, which exerted its action via its receptor, decreased Glu release induced by MAP, and attenuated the changes in glutamatergic neurotransmission partially via regulation of NR1 and GLT1 expression. OT-induced extracellular GABA increase also suggests that OT acts potentially as an inhibitory neuromodulator in mPFC and DHC of mice. PMID:22507692

  15. Changes in functional connectivity and GABA levels with long-term motor learning.

    Science.gov (United States)

    Sampaio-Baptista, Cassandra; Filippini, Nicola; Stagg, Charlotte J; Near, Jamie; Scholz, Jan; Johansen-Berg, Heidi

    2015-02-01

    Learning novel motor skills alters local inhibitory circuits within primary motor cortex (M1) (Floyer-Lea et al., 2006) and changes long-range functional connectivity (Albert et al., 2009). Whether such effects occur with long-term training is less well established. In addition, the relationship between learning-related changes in functional connectivity and local inhibition, and their modulation by practice, has not previously been tested. Here, we used resting-state functional magnetic resonance imaging (rs-fMRI) to assess functional connectivity and MR spectroscopy to quantify GABA in primary motor cortex (M1) before and after a 6 week regime of juggling practice. Participants practiced for either 30 min (high intensity group) or 15 min (low intensity group) per day. We hypothesized that different training regimes would be reflected in distinct changes in brain connectivity and local inhibition, and that correlations would be found between learning-induced changes in GABA and functional connectivity. Performance improved significantly with practice in both groups and we found no evidence for differences in performance outcomes between the low intensity and high intensity groups. Despite the absence of behavioral differences, we found distinct patterns of brain change in the two groups: the low intensity group showed increases in functional connectivity in the motor network and decreases in GABA, whereas the high intensity group showed decreases in functional connectivity and no significant change in GABA. Changes in functional connectivity correlated with performance outcome. Learning-related changes in functional connectivity correlated with changes in GABA. The results suggest that different training regimes are associated with distinct patterns of brain change, even when performance outcomes are comparable between practice schedules. Our results further indicate that learning-related changes in resting-state network strength in part reflect GABAergic plastic

  16. An altered GABA-A receptor function in spinocerebellar ataxia type 6 and familial hemiplegic migraine type 1 associated with the CACNA1A gene mutation

    Directory of Open Access Journals (Sweden)

    Satoshi Kono

    2014-12-01

    General significance: An altered GABA-A receptor function has previously been reported in models of inherited murine cerebellar ataxia caused by a mutation in the CACNA1A gene. This study showed novel clinical characteristics of alteration in the GABA-A receptor in vivo, which may provide clinical evidence indicating a pathological mechanism common to neurological disorders associated with CACNA1A gene mutation.

  17. GABA Neuron Alterations, Cortical Circuit Dysfunction and Cognitive Deficits in Schizophrenia

    OpenAIRE

    Guillermo Gonzalez-Burgos; Fish, Kenneth N.; Lewis, David A.

    2011-01-01

    Schizophrenia is a brain disorder associated with cognitive deficits that severely affect the patients' capacity for daily functioning. Whereas our understanding of its pathophysiology is limited, postmortem studies suggest that schizophrenia is associated with deficits of GABA-mediated synaptic transmission. A major role of GABA-mediated transmission may be producing synchronized network oscillations which are currently hypothesized to be essential for normal cognitive function. Therefore, c...

  18. A neuronal disruption in redox homeostasis elicited by ammonia alters the glycine/glutamate (GABA) cycle and contributes to MMA-induced excitability.

    Science.gov (United States)

    Royes, Luiz Fernando Freire; Gabbi, Patrícia; Ribeiro, Leandro Rodrigo; Della-Pace, Iuri Domingues; Rodrigues, Fernanda Silva; de Oliveira Ferreira, Ana Paula; da Silveira Junior, Mauro Eduardo Porto; da Silva, Luís Roberto Hart; Grisólia, Alan Barroso Araújo; Braga, Danielle Valente; Dobrachinski, Fernando; da Silva, Anderson Manoel Herculano Oliveira; Soares, Félix Alexandre Antunes; Marchesan, Sara; Furian, Ana Flavia; Oliveira, Mauro Schneider; Fighera, Michele Rechia

    2016-06-01

    Hyperammonemia is a common finding in children with methylmalonic acidemia. However, its contribution to methylmalonate-induced excitotoxicty is poorly understood. The aim of this study was to evaluate the mechanisms by which ammonia influences in the neurotoxicity induced by methylmalonate (MMA) in mice. The effects of ammonium chloride (NH4Cl 3, 6, and 12 mmol/kg; s.c.) on electroencephalographic (EEG) and behavioral convulsions induced by MMA (0.3, 0.66, and 1 µmol/2 µL, i.c.v.) were observed in mice. After, ammonia, TNF-α, IL1β, IL-6, nitrite/nitrate (NOx) levels, mitochondrial potential (ΔΨ), reactive oxygen species (ROS) generation, Methyl-Tetrazolium (MTT) reduction, succinate dehydrogenase (SDH), and Na(+), K(+)-ATPase activity levels were measured in the cerebral cortex. The binding of [(3)H]flunitrazepam, release of glutamate-GABA; glutamate decarboxylase (GAD) and glutamine synthetase (GS) activity and neuronal damage [opening of blood brain barrier (BBB) permeability and cellular death volume] were also measured. EEG recordings showed that an intermediate dose of NH4Cl (6 mmol/kg) increased the duration of convulsive episodes induced by MMA (0.66 μmol/2 μL i.c.v). NH4Cl (6 mmol/kg) administration also induced neuronal ammonia and NOx increase, as well as mitochondrial ROS generation throughout oxidation of 2,7-dichlorofluorescein diacetate (DCFH-DA) to DCF-RS, followed by GS and GAD inhibition. The NH4Cl plus MMA administration did not alter cytokine levels, plasma fluorescein extravasation, or neuronal damage. However, it potentiated DCF-RS levels, decreased the ΔΨ potential, reduced MTT, inhibited SDH activity, and increased Na(+), K(+)-ATPase activity. NH4Cl also altered the GABA cycle characterized by GS and GAD activity inhibition, [(3)H]flunitrazepam binding, and GABA release after MMA injection. On the basis of our findings, the changes in ROS and reactive nitrogen species (RNS) levels elicited by ammonia alter the glycine

  19. L-DOPA Reverses the Increased Free Amino Acids Tissue Levels Induced by Dopamine Depletion and Rises GABA and Tyrosine in the Striatum.

    Science.gov (United States)

    Solís, Oscar; García-Sanz, Patricia; Herranz, Antonio S; Asensio, María-José; Moratalla, Rosario

    2016-07-01

    Perturbations in the cerebral levels of various amino acids are associated with neurological disorders, and previous studies have suggested that such alterations have a role in the motor and non-motor symptoms of Parkinson's disease. However, the direct effects of chronic L-DOPA treatment, that produces dyskinesia, on neural tissue amino acid concentrations have not been explored in detail. To evaluate whether striatal amino acid concentrations are altered in peak dose dyskinesia, 6-hydroxydopamine (6-OHDA)-lesioned hemiparkinsonian mice were treated chronically with L-DOPA and tissue amino acid concentrations were assessed by HPLC analysis. These experiments revealed that neither 6-OHDA nor L-DOPA treatment are able to alter glutamate in the striatum. However, glutamine increases after 6-OHDA and returns back to normal levels with L-DOPA treatment, suggesting increased striatal glutamatergic transmission with lack of dopamine. In addition, glycine and taurine levels are increased following dopamine denervation and restored to normal levels by L-DOPA. Interestingly, dyskinetic animals showed increased levels of GABA and tyrosine, while aspartate striatal tissue levels are not altered. Overall, our results indicate that chronic L-DOPA treatment, besides normalizing the altered levels of some amino acids after 6-OHDA, robustly increases striatal GABA and tyrosine levels which may in turn contribute to the development of L-DOPA-induced dyskinesia. PMID:26966009

  20. Dependence-induced ethanol drinking and GABA neurotransmission are altered in Alk deficient mice.

    Science.gov (United States)

    Schweitzer, Paul; Cates-Gatto, Chelsea; Varodayan, Florence P; Nadav, Tali; Roberto, Marisa; Lasek, Amy W; Roberts, Amanda J

    2016-08-01

    Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase that is expressed in the brain and implicated in alcohol abuse in humans and behavioral responses to ethanol in mice. Previous studies have shown an association of human ALK with acute responses to alcohol and alcohol dependence. In addition, Alk knockout (Alk -/-) mice consume more ethanol in a binge-drinking test and show increased sensitivity to ethanol sedation. However, the function of ALK in excessive drinking following the establishment of ethanol dependence has not been examined. In this study, we tested Alk -/- mice for dependence-induced drinking using the chronic intermittent ethanol-two bottle choice drinking (CIE-2BC) protocol. We found that Alk -/- mice initially consume more ethanol prior to CIE exposure, but do not escalate ethanol consumption after exposure, suggesting that ALK may promote the escalation of drinking after ethanol dependence. To determine the mechanism(s) responsible for this behavioral phenotype we used an electrophysiological approach to examine GABA neurotransmission in the central nucleus of the amygdala (CeA), a brain region that regulates alcohol consumption and shows increased GABA signaling after chronic ethanol exposure. GABA transmission in ethanol-naïve Alk -/- mice was enhanced at baseline and potentiated in response to acute ethanol application when compared to wild-type (Alk +/+) mice. Moreover, basal GABA transmission was not elevated by CIE exposure in Alk -/- mice as it was in Alk +/+ mice. These data suggest that ALK plays a role in dependence-induced drinking and the regulation of presynaptic GABA release in the CeA. PMID:26946429

  1. GABA-A receptor-mediated signaling alters the structure of spontaneous activity in the developing retina

    OpenAIRE

    Wang, Chih-Tien; Blankenship, Aaron G.; Anishchenko, Anastasia; Elstrott, Justin; Fikhman, Michael; Nakanishi, Shigetada; Feller, Marla B

    2007-01-01

    Ambient GABA modulates firing patterns in adult neural circuits by tonically activating extrasynaptic GABA-A receptors. Here, we demonstrate that during a developmental period when activation of GABA-A receptors causes membrane depolarization, tonic activation of GABA-A receptors blocks all spontaneous activity recorded in retinal ganglion cells (RGCs) and starburst amacrine cells (SACs). Bath application of the GABA-A receptor agonist muscimol blocked spontaneous correlated increases in intr...

  2. Seizure-induced alterations in fast-spiking basket cell GABA currents modulate frequency and coherence of gamma oscillation in network simulations

    Energy Technology Data Exchange (ETDEWEB)

    Proddutur, Archana; Yu, Jiandong; Elgammal, Fatima S. [Department of Neurology and Neurosciences, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States); Santhakumar, Vijayalakshmi, E-mail: santhavi@njms.rutgers.edu [Department of Neurology and Neurosciences, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States); Department of Pharmacology and Physiology, New Jersey Medical School, Rutgers, Newark, New Jersey 07103 (United States)

    2013-12-15

    Gamma frequency oscillations have been proposed to contribute to memory formation and retrieval. Fast-spiking basket cells (FS-BCs) are known to underlie development of gamma oscillations. Fast, high amplitude GABA synapses and gap junctions have been suggested to contribute to gamma oscillations in FS-BC networks. Recently, we identified that, apart from GABAergic synapses, FS-BCs in the hippocampal dentate gyrus have GABAergic currents mediated by extrasynaptic receptors. Our experimental studies demonstrated two specific changes in FS-BC GABA currents following experimental seizures [Yu et al., J. Neurophysiol. 109, 1746 (2013)]: increase in the magnitude of extrasynaptic (tonic) GABA currents and a depolarizing shift in GABA reversal potential (E{sub GABA}). Here, we use homogeneous networks of a biophysically based model of FS-BCs to examine how the presence of extrasynaptic GABA conductance (g{sub GABA-extra}) and experimentally identified, seizure-induced changes in g{sub GABA-extra} and E{sub GABA} influence network activity. Networks of FS-BCs interconnected by fast GABAergic synapses developed synchronous firing in the dentate gamma frequency range (40–100 Hz). Systematic investigation revealed that the biologically realistic range of 30 to 40 connections between FS-BCs resulted in greater coherence in the gamma frequency range when networks were activated by Poisson-distributed dendritic synaptic inputs rather than by homogeneous somatic current injections, which were balanced for FS-BC firing frequency in unconnected networks. Distance-dependent conduction delay enhanced coherence in networks with 30–40 FS-BC interconnections while inclusion of gap junctional conductance had a modest effect on coherence. In networks activated by somatic current injections resulting in heterogeneous FS-BC firing, increasing g{sub GABA-extra} reduced the frequency and coherence of FS-BC firing when E{sub GABA} was shunting (−74 mV), but failed to alter average

  3. Short-term monocular deprivation alters GABA in the adult human visual cortex.

    Science.gov (United States)

    Lunghi, Claudia; Emir, Uzay E; Morrone, Maria Concetta; Bridge, Holly

    2015-06-01

    Neuroplasticity is a fundamental property of the nervous system that is maximal early in life, within the critical period [1-3]. Resting GABAergic inhibition is necessary to trigger ocular dominance plasticity and to modulate the onset and offset of the critical period [4, 5]. GABAergic inhibition also plays a crucial role in neuroplasticity of adult animals: the balance between excitation and inhibition in the primary visual cortex (V1), measured at rest, modulates the susceptibility of ocular dominance to deprivation [6-10]. In adult humans, short-term monocular deprivation strongly modifies ocular balance, unexpectedly boosting the deprived eye, reflecting homeostatic plasticity [11, 12]. There is no direct evidence, however, to support resting GABAergic inhibition in homeostatic plasticity induced by visual deprivation. Here, we tested the hypothesis that GABAergic inhibition, measured at rest, is reduced by deprivation, as demonstrated by animal studies. GABA concentration in V1 of adult humans was measured using ultra-high-field 7T magnetic resonance spectroscopy before and after short-term monocular deprivation. After monocular deprivation, resting GABA concentration decreased in V1 but was unaltered in a control parietal area. Importantly, across participants, the decrease in GABA strongly correlated with the deprived eye perceptual boost measured by binocular rivalry. Furthermore, after deprivation, GABA concentration measured during monocular stimulation correlated with the deprived eye dominance. We suggest that reduction in resting GABAergic inhibition triggers homeostatic plasticity in adult human V1 after a brief period of abnormal visual experience. These results are potentially useful for developing new therapeutic strategies that could exploit the intrinsic residual plasticity of the adult human visual cortex. PMID:26004760

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

    Directory of Open Access Journals (Sweden)

    Matthew S Stratton

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

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

    Science.gov (United States)

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

    2014-01-01

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

  6. GABA levels in the ventromedial prefrontal cortex during the viewing of appetitive and disgusting food images.

    Science.gov (United States)

    Padulo, Caterina; Delli Pizzi, Stefano; Bonanni, Laura; Edden, Richard A E; Ferretti, Antonio; Marzoli, Daniele; Franciotti, Raffaella; Manippa, Valerio; Onofrj, Marco; Sepede, Gianna; Tartaro, Armando; Tommasi, Luca; Puglisi-Allegra, Stefano; Brancucci, Alfredo

    2016-10-01

    Characterizing how the brain appraises the psychological dimensions of reward is one of the central topics of neuroscience. It has become clear that dopamine neurons are implicated in the transmission of both rewarding information and aversive and alerting events through two different neuronal populations involved in encoding the motivational value and the motivational salience of stimuli, respectively. Nonetheless, there is less agreement on the role of the ventromedial prefrontal cortex (vmPFC) and the related neurotransmitter release during the processing of biologically relevant stimuli. To address this issue, we employed magnetic resonance spectroscopy (MRS), a non-invasive methodology that allows detection of some metabolites in the human brain in vivo, in order to assess the role of the vmPFC in encoding stimulus value rather than stimulus salience. Specifically, we measured gamma-aminobutyric acid (GABA) and, with control purposes, Glx levels in healthy subjects during the observation of appetitive and disgusting food images. We observed a decrease of GABA and no changes in Glx concentration in the vmPFC in both conditions. Furthermore, a comparatively smaller GABA reduction during the observation of appetitive food images than during the observation of disgusting food images was positively correlated with the scores obtained to the body image concerns sub-scale of Body Uneasiness Test (BUT). These results are consistent with the idea that the vmPFC plays a crucial role in processing both rewarding and aversive stimuli, possibly by encoding stimulus salience through glutamatergic and/or noradrenergic projections to deeper mesencephalic and limbic areas. PMID:27436536

  7. GABA and enkephalin tonically alter sympathetic outflows in the rat spinal cord.

    Science.gov (United States)

    Bowman, Belinda R; Goodchild, Ann K

    2015-12-01

    GABA and enkephalin provide significant innervation of sympathetic preganglionic neurons. Despite some investigation as to the identity of premotor sources of these innervations no comprehensive analyses have been conducted. Similarly, although data describing the cardiovascular effects of blockade of GABAA receptors in the spinal cord is available, the effects at other sympathetic outflows are unknown. In contrast the sympathetic effects of opioid blockade in the spinal cord are unclear. The aims of this study were to identify potential sympathetic premotor sources of GABAergic and enkephalinergic input to the spinal cord and to describe the sympathetic and cardiovascular effects of spinal GABAA receptor and delta/mu opioid receptor blockade in urethane anaesthetised rats. Glutamic acid decarboxylase (GAD67) and preproenkephalin (PPE) mRNA were found in all regions containing sympathetic premotor neurons, with the medullary raphe and RVMM providing the major GABAergic projections, while the PVN, RVMM and medullary raphe provided the major enkephalinergic projections. Intrathecal injection of bicuculline, a GABAA antagonist, elicited large and prolonged increases in all outflows measured, confirming previous work describing a tonic GABAergic influence on vasomotor tone, and revealing a tonic GABAergic inhibition of interscapular brown adipose tissue temperature. Intrathecal naloxone elicited transient small inhibitory effects only on MAP and HR. Thus GABA acting in the spinal cord plays an important role in the tonic suppression of sympathetic outflows while enkephalin appears to play only a minor role. PMID:26329875

  8. GABA controls the level of quorum-sensing signal in Agrobacterium tumefaciens

    OpenAIRE

    Chevrot, Romain; Rosen, Ran; Haudecoeur, Elise; Cirou, Amélie; Shelp, Barry J.; Ron, Eliora; Faure, Denis

    2006-01-01

    The concentration of GABA increases rapidly in wounded plant tissues, but the implication of this GABA pulse for plant–bacteria interactions is not known. Here we reveal that GABA stimulated the inactivation of the N-(3-oxooctanoyl)homoserine lactone (OC8-HSL) quorum-sensing signal (or “quormone”) by the Agrobacterium lactonase AttM. GABA induced the expression of the attKLM operon, which was correlated to a decrease in OC8-HSL concentration in Agrobacterium tumefaciens cultures. The Agrobact...

  9. GABA FUNCTION IS ALTERED FOLLOWING DEVELOPMENTAL HYPOTHYROIDISM: NEUROANATOMICAL AND NEUROPHYSIOLOGICAL EVIDENCE.

    Science.gov (United States)

    Thyroid hormone deficiency during development produces changes in the structure of neurons and glial cells and alters synaptic function in the hippocampus. GABAergic interneurons comprise the bulk of local inhibitory neuronal circuitry and a subpopulation of these interneurons ...

  10. Seizure-induced alterations in fast-spiking basket cell GABA currents modulate frequency and coherence of gamma oscillation in network simulations

    Science.gov (United States)

    Proddutur, Archana; Yu, Jiandong; Elgammal, Fatima S.; Santhakumar, Vijayalakshmi

    2013-12-01

    Gamma frequency oscillations have been proposed to contribute to memory formation and retrieval. Fast-spiking basket cells (FS-BCs) are known to underlie development of gamma oscillations. Fast, high amplitude GABA synapses and gap junctions have been suggested to contribute to gamma oscillations in FS-BC networks. Recently, we identified that, apart from GABAergic synapses, FS-BCs in the hippocampal dentate gyrus have GABAergic currents mediated by extrasynaptic receptors. Our experimental studies demonstrated two specific changes in FS-BC GABA currents following experimental seizures [Yu et al., J. Neurophysiol. 109, 1746 (2013)]: increase in the magnitude of extrasynaptic (tonic) GABA currents and a depolarizing shift in GABA reversal potential (EGABA). Here, we use homogeneous networks of a biophysically based model of FS-BCs to examine how the presence of extrasynaptic GABA conductance (gGABA-extra) and experimentally identified, seizure-induced changes in gGABA-extra and EGABA influence network activity. Networks of FS-BCs interconnected by fast GABAergic synapses developed synchronous firing in the dentate gamma frequency range (40-100 Hz). Systematic investigation revealed that the biologically realistic range of 30 to 40 connections between FS-BCs resulted in greater coherence in the gamma frequency range when networks were activated by Poisson-distributed dendritic synaptic inputs rather than by homogeneous somatic current injections, which were balanced for FS-BC firing frequency in unconnected networks. Distance-dependent conduction delay enhanced coherence in networks with 30-40 FS-BC interconnections while inclusion of gap junctional conductance had a modest effect on coherence. In networks activated by somatic current injections resulting in heterogeneous FS-BC firing, increasing gGABA-extra reduced the frequency and coherence of FS-BC firing when EGABA was shunting (-74 mV), but failed to alter average FS-BC frequency when EGABA was depolarizing

  11. Multi-regional investigation of the relationship between functional MRI blood oxygenation level dependent (BOLD activation and GABA concentration.

    Directory of Open Access Journals (Sweden)

    Ashley D Harris

    Full Text Available Several recent studies have reported an inter-individual correlation between regional GABA concentration, as measured by MRS, and the amplitude of the functional blood oxygenation level dependent (BOLD response in the same region. In this study, we set out to investigate whether this coupling generalizes across cortex. In 18 healthy participants, we performed edited MRS measurements of GABA and BOLD-fMRI experiments using regionally related activation paradigms. Regions and tasks were the: occipital cortex with a visual grating stimulus; auditory cortex with a white noise stimulus; sensorimotor cortex with a finger-tapping task; frontal eye field with a saccade task; and dorsolateral prefrontal cortex with a working memory task. In contrast to the prior literature, no correlation between GABA concentration and BOLD activation was detected in any region. The origin of this discrepancy is not clear. Subtle differences in study design or insufficient power may cause differing results; these and other potential reasons for the discrepant results are discussed. This negative result, although it should be interpreted with caution, has a larger sample size than prior positive results, and suggests that the relationship between GABA and the BOLD response may be more complex than previously thought.

  12. Assessment of the Level of GABA and Some Trace Elements in Blood in Children who Suffer from Familial Febrile Convulsions

    Directory of Open Access Journals (Sweden)

    Osama N. Salah

    2014-03-01

    Full Text Available Febrile seizure is one of the most common neurological problems during childhood. The etiology and pathogenesis of febrile seizure remain unknown. However, several factors such as vitamin B6 deficiency, electrolyte disturbances, and reduction in serum zinc, selenium, magnesium levels, and low gamma - aminobutyric acid (GABA levels are thought to play a role in the pathogenesis of febrile seizure. The present study included twenty children from 10 families, 11 were male and 9 were female. Each family has at least 2 members with a history of febrile convulsion. All cases were subjected to the following: Determination of serum levels of copper, zinc, magnesium, selenium level in serum, and plasma level of γ-aminobytaric acid (GABA. Serum levels of selenium and GABA were statistically significantly low in comparison with controls. Serum copper was statistically significantly higher in cases than controls, while serum zinc showed no significant changes in the cases of febrile convulsion compared with the control group. The mean Zn level in the serum of febrile convulsion was found to be at lower level than in the control group. The serum magnesium was significantly low in cases than controls. The logistic regression model in our study shows that Selenium and Magnesium have protective effects, while Copper has causative effect.

  13. IGF-1 Restores Visual Cortex Plasticity in Adult Life by Reducing Local GABA Levels

    Directory of Open Access Journals (Sweden)

    José Fernando Maya-Vetencourt

    2012-01-01

    Full Text Available The central nervous system architecture is markedly modified by sensory experience during early life, but a decline of plasticity occurs with age. Recent studies have challenged this dogma providing evidence that both pharmacological treatments and paradigms based on the manipulation of environmental stimulation levels can be successfully employed as strategies for enhancing plasticity in the adult nervous system. Insulin-like growth factor 1 (IGF-1 is a peptide implicated in prenatal and postnatal phases of brain development such as neurogenesis, neuronal differentiation, synaptogenesis, and experience-dependent plasticity. Here, using the visual system as a paradigmatic model, we report that IGF-1 reactivates neural plasticity in the adult brain. Exogenous administration of IGF-1 in the adult visual cortex, indeed, restores the susceptibility of cortical neurons to monocular deprivation and promotes the recovery of normal visual functions in adult amblyopic animals. These effects were accompanied by a marked reduction of intracortical GABA levels. Moreover, we show that a transitory increase of IGF-1 expression is associated to the plasticity reinstatement induced by environmental enrichment (EE and that blocking IGF-1 action by means of the IGF-1 receptor antagonist JB1 prevents EE effects on plasticity processes.

  14. Near-future carbon dioxide levels alter fish behaviour by interfering with neurotransmitter function

    Science.gov (United States)

    Nilsson, Göran E.; Dixson, Danielle L.; Domenici, Paolo; McCormick, Mark I.; Sørensen, Christina; Watson, Sue-Ann; Munday, Philip L.

    2012-03-01

    Predicted future CO2 levels have been found to alter sensory responses and behaviour of marine fishes. Changes include increased boldness and activity, loss of behavioural lateralization, altered auditory preferences and impaired olfactory function. Impaired olfactory function makes larval fish attracted to odours they normally avoid, including ones from predators and unfavourable habitats. These behavioural alterations have significant effects on mortality that may have far-reaching implications for population replenishment, community structure and ecosystem function. However, the underlying mechanism linking high CO2 to these diverse responses has been unknown. Here we show that abnormal olfactory preferences and loss of behavioural lateralization exhibited by two species of larval coral reef fish exposed to high CO2 can be rapidly and effectively reversed by treatment with an antagonist of the GABA-A receptor. GABA-A is a major neurotransmitter receptor in the vertebrate brain. Thus, our results indicate that high CO2 interferes with neurotransmitter function, a hitherto unrecognized threat to marine populations and ecosystems. Given the ubiquity and conserved function of GABA-A receptors, we predict that rising CO2 levels could cause sensory and behavioural impairment in a wide range of marine species, especially those that tightly control their acid-base balance through regulatory changes in HCO3- and Cl- levels.

  15. Levels of glutamate, aspartate, GABA, and taurine in different regions of the cerebellum after x-irradiation-induced neuronal loss

    International Nuclear Information System (INIS)

    The levels of glutamate (Glu), aspartate (Asp), gamma-amino-n-butyric acid (GABA), and taurine (Tau) were determined in the cortex, molecular layer, and deep nuclei of cerebella of adult rats exposed to X-irradiation at 12-15 days following birth (to prevent the acquisition of late-forming granule cells; 12-15x group) and 8-15 days following birth (to prevent the acquisition of granule and stellate cells; 8-15x group). Also, the levels of the four amino acids were measured in the crude synaptosomal fraction (P2) isolated from the whole cerebella of the control, 12-15x, and 8-15x groups. The level of Glu was significantly decreased by (1) 6-20% in the cerebellar cortex; (2) 15-20% in the molecular layer; and (3) 25-50% in the P2 fraction of the X-irradiated groups relative to control values. The content of Glu in the deep nuclei was not changed by X-irradiation treatment. Regional levels of Asp were unchanged by X-irradiation, while its level in P2 decreased by 15-30% after treatment. The levels of GABA and Tau in the molecular layer, deep nuclei, or P2 were not changed in the experimental groups. However, there was a 15% increase in the levels of GABA and Tau in the cerebellar cortex of the 8-15x group relative to control values. The data support the proposed role of glutamate as the excitatory transmitter released from the cerebellar granule cells but are inconclusive regarding a transmitter role for either Tau or GABA from cerebellar stellate cells

  16. Zero net flux estimates of septal extracellular glucose levels and the effects of glucose on septal extracellular GABA levels

    OpenAIRE

    Krebs-Kraft, Desiree L.; Rauw, Gail; Baker, Glen B.; Parent, Marise B.

    2009-01-01

    Although hippocampal infusions of glucose enhance memory, we have found repeatedly that septal glucose infusions impair memory when γ-aminobutyric acid (GABA) receptors are activated. For instance, hippocampal glucose infusions reverse the memory-impairing effects of co-infusions of the GABA agonist muscimol, whereas septal glucose infusions exacerbate memory deficits produced by muscimol. One potential explanation for these deleterious effects of glucose in the septum is that there are highe...

  17. Levels of glutamate, aspartate, GABA, and taurine in different regions of the cerebellum after x-irradiation-induced neuronal loss

    International Nuclear Information System (INIS)

    The levels of glutamate (Glu), aspartate (Asp), gamma-amino-n-butyric acid (GABA), and taurine (Tau) were determined in the cortex, molecular layer, and deep nuclei of cerebella of adult rats exposed to x-irradiation at 12 to 15 days following birth (to prevent the acquisition of late-forming granule cells; 12 to 15x group) and 8 to 15 days following birth (to prevent the acquisition of granule and stellate cells; 8 to 15x group). Also, the levels of the four amino acids were measured in the crude synaptosomal fraction (P2) isolated from the whole cerebella of the control, 12 to 15x, and 8 to 15x groups. The level of Glu was significantly decreased by (1) 6 to 20% in the cerebellar cortex; (2) 15 to 20% in the molecular layer; and (3) 25 to 50% in the P2 fraction of the x-irradiated groups relative to control values. The content of Glu in the deep nuclei was not changed by x-irradiation treatment. Regional levels of Asp were unchanged by x-irradiation, while its level in P2 decreased by 15 to 30% after treatment. The levels of GABA and Tau in the molecular layer, deep nuclei, or P2 were not changed in the experimental groups. However, there was a 15% increase in the levels of GABA and Tau in the cerebellar cortex of the 8 to 15x group relative to control values. The data support the proposed role of glutamate as the excitatory transmitter released from the cerebellar granule cells but are inconclusive regarding a transmitter role for either Tau or GBA from cerebellar stellate cells

  18. Suppression of γ-Aminobutyric Acid (GABA) Transaminases Induces Prominent GABA Accumulation, Dwarfism and Infertility in the Tomato (Solanum lycopersicum L.)

    OpenAIRE

    Koike, Satoshi; Matsukura, Chiaki; Takayama, Mariko; Asamizu, Erika; Ezura, Hiroshi

    2013-01-01

    Tomatoes accumulate γ-aminobutyric acid (GABA) at high levels in the immature fruits. GABA is rapidly converted to succinate during fruit ripening through the activities of GABA transaminase (GABA-T) and succinate semialdehyde dehydrogenase (SSADH). Although three genes encoding GABA-T and both pyruvate- and α-ketoglutarate-dependent GABA-T activities have been detected in tomato fruits, the mechanism underlying the GABA-T-mediated conversion of GABA has not been fully understood. In this wor...

  19. GABA(A) receptor density is altered by cannabinoid treatment in the hippocampus of adult but not adolescent rats.

    Science.gov (United States)

    Verdurand, Mathieu; Dalton, Victoria Stephanie; Zavitsanou, Katerina

    2010-09-10

    Cannabinoids are known to induce transient psychotic symptoms and cognitive dysfunction in healthy individuals and contribute to trigger schizophrenia in vulnerable individuals, particularly during adolescence. Converging preclinical evidence suggests important interactions between cannabinoid and GABAergic systems. In the present study, we compared the effects of cannabinoid treatment on GABA(A) receptor binding in the brain of adolescent and adult rats. Adolescent (5 weeks old) and adult (10 weeks old) rats were treated with the synthetic cannabinoid HU210 (25, 50 or 100 microg/kg/day) or vehicle for 1, 4 or 14 days. Rats were sacrificed 24 h after the last injection and GABA(A) receptor density was measured in several brain regions using [(35)S]TBPS and in vitro autoradiography. Adolescent rats had higher numbers of GABA(A) receptors compared to adults. A 24% increase of binding in adult rats treated with 100 microg/kg HU210 for 14 days compared to controls was observed in the CA1 region of the hippocampus (16.1 versus 12.9 fmol/mg tissue equivalent, t=2.720, pHU210 did not affect GABA(A) receptors in adolescent rats in any treatment regimen and in adult rats treated with HU210 for 1 or 4 days. These data suggest that long-term, high-dose treatment with HU210 increases GABA(A) receptors in the hippocampus of adult rats, changes that may interfere with associated hippocampal cognitive functions such as learning and memory. In addition, our results suggest that the adolescent brain does not display the same compensatory mechanisms that are activated in the adult brain following cannabinoid treatment. PMID:20599838

  20. Effect of chronic treatment with the GABA transaminase inhibitors γ-vinyl GABA and ethanolamine O-sulphate on the in vitro GABA release from rat hippocampus

    OpenAIRE

    Qume, M; Fowler, L. J.

    1997-01-01

    The effects of 2, 8 and 21 day oral treatment with the specific γ-aminobutyric acid transaminase (GABA-T) inhibitors γ-vinyl GABA (GVG) and ethanolamine O-sulphate (EOS) on brain GABA levels, GABA-T activity, and basal and stimulated GABA release from rat cross-chopped brain hippocampal slices was investigated.Treatment with GABA-T inhibitors lead to a reduction in brain GABA-T activity by 65–80% compared with control values, with a concomitant increase in brain GABA content of 40–100%.Basal ...

  1. GABA-shunt enzymes activity in GH3 cells with reduced level of PMCA2 or PMCA3 isoform

    Energy Technology Data Exchange (ETDEWEB)

    Kowalski, Antoni, E-mail: antoni.kowalski@umed.lodz.pl [Department of Molecular Neurochemistry, Medical University of Lodz, 6/8 Mazowiecka Str., 92-215 Lodz (Poland); Zylinska, Ludmila, E-mail: ludmila.zylinska@umed.lodz.pl [Department of Molecular Neurochemistry, Medical University of Lodz, 6/8 Mazowiecka Str., 92-215 Lodz (Poland); Boczek, Tomasz, E-mail: tomasz.boczek@umed.lodz.pl [Department of Molecular Neurochemistry, Medical University of Lodz, 6/8 Mazowiecka Str., 92-215 Lodz (Poland); Rebas, Elzbieta, E-mail: elzbieta.rebas@umed.lodz.pl [Department of Molecular Neurochemistry, Medical University of Lodz, 6/8 Mazowiecka Str., 92-215 Lodz (Poland)

    2011-08-12

    Highlights: {yields} Suppression of PMCA2 or PMCA3 slows down proliferation of GH3 cells. {yields} PMCA2 suppression lowers the activity of GABA-shunt enzymes. {yields} PMCA3 suppression increases the expression of glutamate decarboxylase 65. {yields} PMCA2 and PMCA3 function appears to be linked to regulation of GABA metabolism. -- Abstract: GABA ({gamma}-aminobutyric acid) is important neurotransmitter and regulator of endocrine functions. Its metabolism involves three enzymes: glutamate decarboxylase (GAD65 and GAD67), GABA aminotransferase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH). As many cellular processes GABA turnover can depend on calcium homeostasis, which is maintained by plasma membrane calcium ATPases (PMCAs). In excitable cells PMCA2 and PMCA3 isoforms are particularly important. In this study we focused on GABA-metabolizing enzymes expression and activity in rat anterior pituitary GH3 cells with suppressed expression of PMCA2 or PMCA3. We observed that PMCA3-reduced cells have increased GAD65 expression. Suppression of PMCA2 caused a decrease in total GAD and GABA-T activity. These results indicate that PMCA2 and PMCA3 presence may be an important regulatory factor in GABA metabolism. Results suggest that PMCA2 and PMCA3 function is rather related to regulation of GABA synthesis and degradation than supplying cells with metabolites, which can be potentially energetic source.

  2. GABA-shunt enzymes activity in GH3 cells with reduced level of PMCA2 or PMCA3 isoform

    International Nuclear Information System (INIS)

    Highlights: → Suppression of PMCA2 or PMCA3 slows down proliferation of GH3 cells. → PMCA2 suppression lowers the activity of GABA-shunt enzymes. → PMCA3 suppression increases the expression of glutamate decarboxylase 65. → PMCA2 and PMCA3 function appears to be linked to regulation of GABA metabolism. -- Abstract: GABA (γ-aminobutyric acid) is important neurotransmitter and regulator of endocrine functions. Its metabolism involves three enzymes: glutamate decarboxylase (GAD65 and GAD67), GABA aminotransferase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH). As many cellular processes GABA turnover can depend on calcium homeostasis, which is maintained by plasma membrane calcium ATPases (PMCAs). In excitable cells PMCA2 and PMCA3 isoforms are particularly important. In this study we focused on GABA-metabolizing enzymes expression and activity in rat anterior pituitary GH3 cells with suppressed expression of PMCA2 or PMCA3. We observed that PMCA3-reduced cells have increased GAD65 expression. Suppression of PMCA2 caused a decrease in total GAD and GABA-T activity. These results indicate that PMCA2 and PMCA3 presence may be an important regulatory factor in GABA metabolism. Results suggest that PMCA2 and PMCA3 function is rather related to regulation of GABA synthesis and degradation than supplying cells with metabolites, which can be potentially energetic source.

  3. Structure, function, and plasticity of GABA transporters

    OpenAIRE

    Annalisa eScimemi

    2014-01-01

    GABA transporters belong to a large family of neurotransmitter:sodium symporters. They are widely expressed throughout the brain, with different levels of expression in different brain regions. GABA transporters are present in neurons and in astrocytes and their activity is crucial to regulate the extracellular concentration of GABA under basal conditions and during ongoing synaptic events. Numerous efforts have been devoted to determine the structural and functional properties of GABA transp...

  4. Altered Levels of Acetylcholinesterase in Alzheimer Plasma

    OpenAIRE

    García Ayllón, María Salud; Riba Llena, Iolanda; Serra Basante, Carol; Alom, Jordi; Boopathy, Rathnam; Sáez-Valero, Javier

    2010-01-01

    Background Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE) in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE) pose a major problem. Principal Findings Here we have estimated the levels of AChE activity in human plasma by first imm...

  5. Enterik Sinir Sisteminde GABA

    OpenAIRE

    KESİM, S.M.

    2010-01-01

    GABA in Enteric Nervous System y-Aminobutyric acid (GABA) is a well known inhibitory neurotransmitter in the mammalian central nervous system. GABA may be a neurotransmitter in the vertebrate peripheral nervous system, evidence has accumulated demostrating the presence of GABA receptors in the gastrointestinal tract. GABA and its metabolic enzymes (GAD and GABA-T) are present in the myenteric plexus of the enteric nervous system. High affinity GABA uptake in the plexus has been shown by re...

  6. Changes in functional connectivity and GABA levels with long-term motor learning

    OpenAIRE

    Sampaio-Baptista, Cassandra; Filippini, Nicola; Stagg, Charlotte J.; Near, Jamie; Scholz, Jan; Johansen-Berg, Heidi

    2015-01-01

    Learning novel motor skills alters local inhibitory circuits within primary motor cortex (M1) (Floyer-Lea et al., 2006) and changes long-range functional connectivity (Albert et al., 2009). Whether such effects occur with long-term training is less well established. In addition, the relationship between learning-related changes in functional connectivity and local inhibition, and their modulation by practice, has not previously been tested. Here, we used resting-state functional magnetic reso...

  7. [GABA-ergic system in defense against excitatory kynurenines].

    Science.gov (United States)

    Lapin, I P

    1997-01-01

    Protection against the excitatory action of L-kynurenine and quinolinic acid in mice is related to the activation of GABA-B and dopamine receptors of the brain and to much lesser degree to the activation of GABA-A receptors. It is hardly believable that the anticonvulsant effect of phenibut (beta-phenyl-GABA), baclofen (CL-phenibut), sodium hydroxybutyrate and taurine against seizures induced by these two kynurenines is determined by alterations in metabolism of GABA. PMID:9503572

  8. GABA transporter-1 deficiency confers schizophrenia-like behavioral phenotypes.

    Directory of Open Access Journals (Sweden)

    Zhe Yu

    Full Text Available The mechanism underlying the pathogenesis of schizophrenia remains poorly understood. The hyper-dopamine and hypo-NMDA receptor hypotheses have been the most enduring ideas. Recently, emerging evidence implicates alterations of the major inhibitory system, GABAergic neurotransmission in the schizophrenic patients. However, the pathophysiological role of GABAergic system in schizophrenia still remains dubious. In this study, we took advantage of GABA transporter 1 (GAT1 knockout (KO mouse, a unique animal model with elevated ambient GABA, to study the schizophrenia-related behavioral abnormalities. We found that GAT1 KO mice displayed multiple behavioral abnormalities related to schizophrenic positive, negative and cognitive symptoms. Moreover, GAT1 deficiency did not change the striatal dopamine levels, but significantly enhanced the tonic GABA currents in prefrontal cortex. The GABA(A receptor antagonist picrotoxin could effectively ameliorate several behavioral defects of GAT1 KO mice. These results identified a novel function of GAT1, and indicated that the elevated ambient GABA contributed critically to the pathogenesis of schizophrenia. Furthermore, several commonly used antipsychotic drugs were effective in treating the locomotor hyperactivity in GAT1 KO mice, suggesting the utility of GAT1 KO mice as an alternative animal model for studying schizophrenia pathogenesis and developing new antipsychotic drugs.

  9. GABA[subscript A] Receptor Downregulation in Brains of Subjects with Autism

    Science.gov (United States)

    Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Thuras, Paul D.

    2009-01-01

    Gamma-aminobutyric acid A (GABA[subscript A]) receptors are ligand-gated ion channels responsible for mediation of fast inhibitory action of GABA in the brain. Preliminary reports have demonstrated altered expression of GABA receptors in the brains of subjects with autism suggesting GABA/glutamate system dysregulation. We investigated the…

  10. Altered levels of acetylcholinesterase in Alzheimer plasma.

    Directory of Open Access Journals (Sweden)

    María-Salud García-Ayllón

    Full Text Available BACKGROUND: Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE pose a major problem. PRINCIPAL FINDINGS: Here we have estimated the levels of AChE activity in human plasma by first immunoprecipitating BuChE and measuring AChE activity in the immunodepleted plasma. Human plasma AChE activity levels were approximately 20 nmol/min/mL, about 160 times lower than BuChE. The majority of AChE species are the light G(1+G(2 forms and not G(4 tetramers. The levels and pattern of the molecular forms are similar to that observed in individuals with silent BuChE. We have also compared plasma AChE with the enzyme pattern obtained from human liver, red blood cells, cerebrospinal fluid (CSF and brain, by sedimentation analysis, Western blotting and lectin-binding analysis. Finally, a selective increase of AChE activity was detected in plasma from Alzheimer's disease (AD patients compared to age and gender-matched controls. This increase correlates with an increase in the G(1+G(2 forms, the subset of AChE species which are increased in Alzheimer's brain. Western blot analysis demonstrated that a 78 kDa immunoreactive AChE protein band was also increased in Alzheimer's plasma, attributed in part to AChE-T subunits common in brain and CSF. CONCLUSION: Plasma AChE might have potential as an indicator of disease progress and prognosis in AD and warrants further investigation.

  11. GABA Receptors Genes Polymorphisms and Alcohol Dependence: No Evidence of an Association in an Italian Male Population

    OpenAIRE

    Terranova, Claudio; Tucci, Marianna; Di Pietra, Laura; Ferrara, Santo Davide

    2014-01-01

    Objective The genes encoding for gamma-aminobutyric acid (GABA) A and B receptors may be considered as candidates for alcoholism; genetic alterations at this level may produce structural and functional diversity and thus play a role in the response to alcohol addiction treatment. To investigate these aspects further, we conducted a preliminary genetic association study on a population of Italian male alcohol addicts, focusing on GABA A and B receptors. Methods A total of 186 alcohol-dependent...

  12. Motor Alterations Induced by Chronic 4-Aminopyridine Infusion in the Spinal Cord In vivo: Role of Glutamate and GABA Receptors

    Science.gov (United States)

    Lazo-Gómez, Rafael; Tapia, Ricardo

    2016-01-01

    Motor neuron (MN) degeneration is the pathological hallmark of MN diseases, a group of neurodegenerative disorders clinically manifested as muscle fasciculations and hyperreflexia, followed by paralysis, respiratory failure, and death. Ample evidence supports a role of glutamate-mediated excitotoxicity in motor death. In previous work we showed that stimulation of glutamate release from nerve endings by perfusion of the K+-channel blocker 4-aminopyridine (4-AP) in the rat hippocampus induces seizures and neurodegeneration, and that AMPA infusion in the spinal cord produces paralysis and MN death. On these bases, in this work we have tested the effect of the chronic infusion of 4-AP in the spinal cord, using implanted osmotic minipumps, on motor activity and on MN survival, and the mechanisms underlying this effect. 4-AP produced muscle fasciculations and motor deficits assessed in two motor tests, which start 2–3 h after the implant, which ameliorated spontaneously within 6–7 days, but no neurodegeneration. These effects were prevented by both AMPA and NMDA receptors blockers. The role of GABAA receptors was also explored, and we found that chronic infusion of bicuculline induced moderate MN degeneration and enhanced the hyperexcitation produced by 4-AP. Unexpectedly, the GABAAR agonist muscimol also induced motor deficits and failed to prevent the MN death induced by AMPA. We conclude that motor alterations induced by chronic 4-AP infusion in the spinal cord in vivo is due to ionotropic glutamate receptor overactivation and that blockade of GABAergic neurotransmission induces MN death under chronic conditions. These results shed light on the role of glutamatergic and GABAergic neurotransmission in the regulation of MN excitability in the spinal cord. PMID:27242406

  13. GABA receptor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA{sub A}-receptor that allows chloride to pass through a ligand gated ion channel and GABA{sub B}-receptor that uses G-proteins for signaling. The GABA{sub A}-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA{sub A}-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with {sup 11}C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, {sup 18}F-fluoroflumazenil (FFMZ) has been developed to overcome {sup 11}C's short half-life. {sup 18}F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1{sup 1}C-FMZ PET instead of {sup 18}F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA{sub A} receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

  14. Immunocytochemical and autoradiographic studies of the endocrine cells interacting with GABA in the rat stomach.

    OpenAIRE

    Gilon, Patrick; Mallefet, Jérôme; De Vriendt, C; Pauwels, S.; Geffard, M.; Campistron, G.; Remacle, Claude

    1990-01-01

    There are now increasing evidences suggesting that GABA is able of direct interaction with certain endocrine cells. In the present study, highly specific anti-GABA-glutaraldehyde antibodies and 3H-GABA uptake were used at the light and electron microscope levels to investigate the occurrence of cells containing endogenous GABA or taking up exogenous GABA in the mucosal antrum and corpus of the rat stomach. Only certain endocrine cell types of both regions were immunostained or grain-labelled....

  15. GABA receptor imaging

    International Nuclear Information System (INIS)

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABAA-receptor that allows chloride to pass through a ligand gated ion channel and GABAB-receptor that uses G-proteins for signaling. The GABAA-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABAA-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with 11C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, 18F-fluoroflumazenil (FFMZ) has been developed to overcome 11C's short half-life. 18F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '11C-FMZ PET instead of 18F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABAA receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas

  16. GABA as a rising gliotransmitter

    OpenAIRE

    Bo-Eun eYoon; C.Justin eLee

    2014-01-01

    Gamma-amino butyric acid (GABA) is the major inhibitory neurotransmitter that is known to be synthesized and released from GABAergic neurons in the brain. However, recent studies have shown that not only neurons but also astrocytes contain a considerable amount of GABA that can be released and activate GABA receptors in neighboring neurons. These exciting new findings for glial GABA raise further interesting questions about the source of GABA, its mechanism of release and regulation and the f...

  17. Synthesis and evaluation of novel heteroaromatic substrates of GABA aminotransferase

    OpenAIRE

    Hawker, Dustin D.; Silverman, Richard B.

    2012-01-01

    Two principal neurotransmitters are involved in the regulation of mammalian neuronal activity, namely, γ-aminobutyric acid (GABA), an inhibitory neurotransmitter, and L-glutamic acid, an excitatory neurotransmitter. Low GABA levels in the brain have been implicated in epilepsy and several other neurological diseases. Because of GABA’s poor ability to cross the blood-brain barrier (BBB), a successful strategy to raise brain GABA concentrations is the use of a compound that does cross the BBB a...

  18. Gamma-aminobutyric acid (GABA in cerebrospinal fluid.

    Directory of Open Access Journals (Sweden)

    Kuroda,Hiroo

    1983-06-01

    Full Text Available Levels of gamma-aminobutyric acid (GABA in cerebrospinal fluid (CSF were measured by radioreceptor assay (RRA in 25 normal controls and in 121 patients with various central nervous system disorders. CSF-GABA levels could be measured down to 5 pmoles/ml reliably by this assay. In normal controls, the mean (+/- SEM GABA level in CSF was 127 +/- 5.2 pmoles/ml. There was no correlation between age, sex and the CSF-GABA level in normal controls. The lowest CSF-GABA level, which was 60 +/- 6.0 pmoles/ml, was observed in alcoholic patients suffering from cerebellar ataxia. The CSF-GABA levels were quite low in patients with Alzheimer's disease, late cortical cerebellar atrophy, neuro-Behcet's syndrome, olivopontocerebellar atrophy, Huntington's chorea, Parkinson's disease and cerebral hemorrhage. On the other hand, the CSF-GABA levels of meningitis patients were significantly increased. These findings suggest that measuring the CSF-GABA level is quite beneficial in the diagnosis and pathophysiological determinations of some diseases.

  19. Distribution of 3H-GABA uptake sites in the nematode Ascaris

    International Nuclear Information System (INIS)

    The distribution of uptake sites for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the nematode Ascaris suum was examined by autoradiography of 3H-GABA uptake. Single neural processes in both the ventral and dorsal nerve cords were labeled with 3H-GABA. Serial section analysis identified the cells of origin of these processes as the RMEV-like and RMED-like neurons. These cells belong to a set of four neurons in the nerve ring, all of which are labeled by 3H-GABA. 3H-GABA labeling of at least two other sets of cephalic neurons was seen. One of these pairs consists of medium-sized lateral ganglia neurons, located at the level of the amphid commissure bundle. A second pair is located in the lateral ganglia at the level of the deirid commissure bundle. The position and size of these lateral ganglia cells suggest that they are the GABA-immunoreactive lateral ganglia cells frequently seen in whole-mount immunocytochemical preparations. Four neuronal cell bodies located in the retrovesicular ganglion were also labeled with 3H-GABA. These cells, which are probably cholinergic excitatory motor neurons, do not contain detectable GABA-like immunoreactivity. Heavy labeling of muscle cells was also observed. The ventral and dorsal nerve cord inhibitory motor neurons, which are known to contain GABA-like immunoreactivity, were not labeled above background with 3H-GABA. Together with the experiments reported previously, these results define three classes of GABA-associated neurons in Ascaris: (1) neurons that contain endogenous GABA and possess a GABA uptake system; (2) neurons that contain endogenous GABA, but that either lack a GABA uptake system or possess a GABA uptake system of low activity; (3) neurons that possess a GABA uptake system, but that lack endogenous GABA

  20. Distribution of 3H-GABA uptake sites in the nematode Ascaris

    Energy Technology Data Exchange (ETDEWEB)

    Guastella, J.; Stretton, A.O. (University of Wisconsin, Madison (USA))

    1991-05-22

    The distribution of uptake sites for the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in the nematode Ascaris suum was examined by autoradiography of 3H-GABA uptake. Single neural processes in both the ventral and dorsal nerve cords were labeled with 3H-GABA. Serial section analysis identified the cells of origin of these processes as the RMEV-like and RMED-like neurons. These cells belong to a set of four neurons in the nerve ring, all of which are labeled by 3H-GABA. 3H-GABA labeling of at least two other sets of cephalic neurons was seen. One of these pairs consists of medium-sized lateral ganglia neurons, located at the level of the amphid commissure bundle. A second pair is located in the lateral ganglia at the level of the deirid commissure bundle. The position and size of these lateral ganglia cells suggest that they are the GABA-immunoreactive lateral ganglia cells frequently seen in whole-mount immunocytochemical preparations. Four neuronal cell bodies located in the retrovesicular ganglion were also labeled with 3H-GABA. These cells, which are probably cholinergic excitatory motor neurons, do not contain detectable GABA-like immunoreactivity. Heavy labeling of muscle cells was also observed. The ventral and dorsal nerve cord inhibitory motor neurons, which are known to contain GABA-like immunoreactivity, were not labeled above background with 3H-GABA. Together with the experiments reported previously, these results define three classes of GABA-associated neurons in Ascaris: (1) neurons that contain endogenous GABA and possess a GABA uptake system; (2) neurons that contain endogenous GABA, but that either lack a GABA uptake system or possess a GABA uptake system of low activity; (3) neurons that possess a GABA uptake system, but that lack endogenous GABA.

  1. Anion transport and GABA signaling

    Directory of Open Access Journals (Sweden)

    Christian Andreas Huebner

    2013-10-01

    Full Text Available Whereas activation of GABAA receptors by GABA usually results in a hyperpolarizing influx of chloride into the neuron, the reversed chloride driving force in the immature nervous system results in a depolarizing efflux of chloride. This GABAergic depolarization is deemed to be important for the maturation of the neuronal network. The concept of a developmental GABA switch has mainly been derived from in vitro experiments and reliable in vivo evidence is still missing. As GABAA receptors are permeable for both chloride and bicarbonate, the net effect of GABA also critically depends on the distribution of bicarbonate. Whereas chloride can either mediate depolarizing or hyperpolarizing currents, bicarbonate invariably mediates a depolarizing current under physiological conditions. Intracellular bicarbonate is quickly replenished by cytosolic carbonic anhydrases. Intracellular bicarbonate levels also depend on different bicarbonate transporters expressed by neurons. The expression of these proteins is not only developmentally regulated but also differs between cell types and even subcellular regions. In this review we will summarize current knowledge about the role of some of these transporters for brain development and brain function.

  2. Biphasic effects of direct, but not indirect, GABA mimetics and antagonists on haloperidol-induced catalepsy.

    Science.gov (United States)

    Worms, P; Lloyd, K G

    1980-03-01

    At very low doses the GABA agonists SL 76002 and muscimol diminish haloperidol-induced catalepsy. At somewhat higher doses these compounds potentiate catalepsy. Biphasic effects on DA-receptor mediated functions have previously been noted with bicuculline and picrotoxinin. In contrast, manipulation of GABA levels by enzyme inhibition induced only a monophasic effect on dopamine-mediated behaviour. The potentiation of GABA levels by enzyme inhibition induced only a monophasic effect on dopamine-mediated behaviour. The potentiation of haloperidol-induced catalepsy by GABA mimetics is also observed with dipropylacetate, delta-aminovaleric acid and gamma-acetylenic GABA. This GABA-mimetic potentiation of catakepsy was blocked by the coadministration of bicuculline. These results confirm and extend the hypothesis that GABA-neurons influence DA neuron function. Furthermore they suggest that more than one group of GABA receptors influence directly and/or indirectly DA neuronal function, with different resultant effects. PMID:7189827

  3. tDCS-induced alterations in GABA concentration within primary motor cortex predict motor learning and motor memory: A 7 T magnetic resonance spectroscopy study

    OpenAIRE

    Kim, Soyoung; Stephenson, Mary C; Morris, Peter G.; Jackson, Stephen R

    2014-01-01

    Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique that alters cortical excitability in a polarity specific manner and has been shown to influence learning and memory. tDCS may have both on-line and after-effects on learning and memory, and the latter are thought to be based upon tDCS-induced alterations in neurochemistry and synaptic function. We used ultra-high-field (7 T) magnetic resonance spectroscopy (MRS), together with a robotic force adaptati...

  4. Developmental exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin may alter LH release patterns by abolishing sex differences in GABA/glutamate cell number and modifying the transcriptome of the male anteroventral periventricular nucleus.

    Science.gov (United States)

    Del Pino Sans, Javier; Clements, Kelsey J; Suvorov, Alexander; Krishnan, Sudha; Adams, Hillary L; Petersen, Sandra L

    2016-08-01

    Developmental exposure to arylhydrocarbon receptor (AhR) ligands abolishes sex differences in a wide range of neural structures and functions. A well-studied example is the anteroventral periventricular nucleus (AVPV), a structure that controls sex-specific luteinizing hormone (LH) release. In the male, testosterone (T) secreted by the developing testes defeminizes LH release mechanisms; conversely, perinatal AhR activation by 2,3,7,8,-tetrachlorodibenzo-p-dioxin (TCDD) blocks defeminization. To better understand developmental mechanisms altered by TCDD exposure, we first verified that neonatal TCDD exposure in male rats prevented the loss of AVPV GABA/glutamate neurons that are critical for female-typical LH surge release. We then used whole genome arrays and quantitative real-time polymerase chain reaction (QPCR) to compare AVPV transcriptomes of males treated neonatally with TCDD or vehicle. Our bioinformatics analyses showed that TCDD enriched gene sets important for neuron development, synaptic transmission, ion homeostasis, and cholesterol biosynthesis. In addition, upstream regulatory analysis suggests that both estrogen receptors (ER) and androgen receptors (AR) regulate genes targeted by TCDD. Of the 23 mRNAs found to be changed by TCDD at least 2-fold (pbrain. These findings provide new insights into how TCDD may interfere with defeminization of LH release patterns. PMID:27185484

  5. Inhibitory role for GABA in autoimmune inflammation

    OpenAIRE

    Bhat, Roopa; Axtell, Robert; Mitra, Ananya; Miranda, Melissa; Lock, Christopher; Tsien, Richard W.; Steinman, Lawrence

    2010-01-01

    GABA, the principal inhibitory neurotransmitter in the adult brain, has a parallel inhibitory role in the immune system. We demonstrate that immune cells synthesize GABA and have the machinery for GABA catabolism. Antigen-presenting cells (APCs) express functional GABA receptors and respond electrophysiologically to GABA. Thus, the immune system harbors all of the necessary constituents for GABA signaling, and GABA itself may function as a paracrine or autocrine factor. These observations led...

  6. GABA selectively increases mucin-1 expression in isolated pig jejunum.

    Science.gov (United States)

    Braun, Hannah-Sophie; Sponder, Gerhard; Pieper, Robert; Aschenbach, Jörg R; Deiner, Carolin

    2015-11-01

    The inhibitory neurotransmitter GABA (γ-aminobutyric acid) is synthesized by glutamic acid decarboxylase, which is expressed in the central nervous system and in various other tissues including the intestine. Moreover, GABA can be ingested in vegetarian diets or produced by bacterial commensals in the gastrointestinal tract. As previous studies in lung have suggested a link between locally increased GABA availability and mucin 5AC production, the present study sought to test whether the presence or lack of GABA (and its precursor glutamine) has an effect on intestinal mucin expression. Porcine jejunum epithelial preparations were incubated with two different amounts of GABA or glutamine on the mucosal side for 4 h, and changes in the relative gene expression of seven different mucins, enzymes involved in mucin shedding, GABA B receptor, enzymes involved in glutamine/GABA metabolism, glutathione peroxidase 2, and interleukin 10 were examined by quantitative PCR (TaqMan(®) assays). Protein expression of mucin-1 (MUC1) was analyzed by Western blot. On the RNA level, only MUC1 was significantly up-regulated by both GABA concentrations compared with the control. Glutamine-treated groups showed the same trend. On the protein level, all treatment groups showed a significantly higher MUC1 expression than the control group. We conclude that GABA selectively increases the expression of MUC1, a cell surface mucin that prevents the adhesion of microorganisms, because of its size and negative charge, and therefore propose that the well-described positive effects of glutamine on enterocytes and intestinal integrity are partly attributable to effects of its metabolite GABA. PMID:26471792

  7. Design and Mechanism of Tetrahydrothiophene-based GABA Aminotransferase Inactivators

    OpenAIRE

    Le, Hoang V.; Hawker, Dustin D.; Wu, Rui; Doud, Emma; Widom, Julia; Sanishvili, Ruslan; Liu, Dali; Kelleher, Neil L.; Silverman, Richard B.

    2015-01-01

    Low levels of γ-aminobutyric acid (GABA), one of two major neurotransmitters that regulate brain neuronal activity, are associated with many neurological disorders, such as epilepsy, Parkinson’s disease, Alzheimer’s disease, Huntington’s disease, and cocaine addiction. One of the main methods to raise the GABA level in human brain is to use small molecules that cross the blood-brain barrier and inhibit the activity of γ-aminobutyric acid aminotransferase (GABA-AT), the enzyme that degrades GA...

  8. GABA Predicts Time Perception

    OpenAIRE

    Terhune, D.B.; S. Russo(Lugano); Near, J; Stagg, C.J.; Cohen Kadosh, R.

    2014-01-01

    Our perception of time constrains our experience of the world and exerts a pivotal influence over a myriad array of cognitive and motor functions. There is emerging evidence that the perceived duration of subsecond intervals is driven by sensory-specific neural activity in human and nonhuman animals, but the mechanisms underlying individual differences in time perception remain elusive. We tested the hypothesis that elevated visual cortex GABA impairs the coding of particular visual stimuli, ...

  9. GABA-BZD Receptor Modulating Mechanism of Panax quinquefolius against 72-hours Sleep Deprivation Induced Anxiety like Behavior: Possible Roles of Oxidative Stress, Mitochondrial Dysfunction and Neuroinflammation

    Directory of Open Access Journals (Sweden)

    Priyanka eChanana

    2016-03-01

    Full Text Available ABSTRACTRationale- Panax quinquefolius (American Ginseng is known for its therapeutic potential against various neurological disorders, but its plausible mechanism of action still remains undeciphered. GABA (Gamma Amino Butyric Acid plays an important role in sleep wake cycle homeostasis. Thus there exists rationale in exploring the GABA-ergic potential of Panax quinquefolius as neuroprotective strategy in sleep deprivation induced secondary neurological problems.Objective- The present study was designed to explore the possible GABA-ergic mechanism in the neuro-protective effect of Panax quinquefolius against 72-hours sleep deprivation induced anxiety like behaviour, oxidative stress, mitochondrial dysfunction, HPA-axis activation and neuroinflammation.Materials and Methods- Male laca mice were sleep deprived for 72-hours by using Grid suspended over water method. Panax quinquefolius (American Ginseng 50, 100 and 200 mg/kg was administered alone and in combination with GABA modulators (GABA Cl- channel inhibitor, GABA-benzodiazepine receptor inhibitor and GABAA agonist for 8 days, starting five days prior to 72-hours sleep deprivation period. Various behavioural (locomotor activity, mirror chamber test, biochemical (lipid peroxidation, reduced glutathione, catalase, nitrite levels, mitochondrial complexes, neuroinflammation marker (Tumour Necrosis Factor, TNF-alpha, serum corticosterone, and histopathological sections of brains were assessed. Results- 72-hours sleep deprivation significantly impaired locomotor activity, caused anxiety-like behaviour, conditions of oxidative stress, alterations in mitochondrial enzyme complex activities, raised serum corticosterone levels, brain TNFα levels and led to neuroinflammation like signs in discrete brain areas as compared to naive group. Panax quinquefolius (100 and 200 mg/kg treatment restored the behavioural, biochemical, mitochondrial, molecular and histopathological alterations. Pre-treatment of

  10. Noisy galvanic vestibular stimulation promotes GABA release in the substantia nigra and improves locomotion in hemiparkinsonian rats.

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    Ghazaleh Samoudi

    Full Text Available BACKGROUND: The vestibular system is connected to spinal, cerebellar and cerebral motor control structures and can be selectively activated with external electrodes. The resulting sensation of disturbed balance can be avoided by using stochastic stimulation patterns. Adding noise to the nervous system sometimes improves function. Small clinical trials suggest that stochastic vestibular stimulation (SVS may improve symptoms in Parkinson's disease. We have investigated this claim and possible mechanisms using the 6-hydroxydopamine (6-OHDA hemilesion model of Parkinson's disease. METHODOLOGY/PRINCIPAL FINDINGS: Animals were tested in the accelerating rod test and the Montoya staircase test of skilled forelimb use. In 6-OHDA hemilesioned animals, SVS improved rod performance by 56±11 s. At group level L-DOPA treatment had no effect, but positive responders improved time on rod by 60±19 s. Skilled forelimb use was not altered by SVS. To investigate how SVS may influence basal ganglia network activity, intracerebral microdialysis was employed in four regions of interest during and after SVS. In presence of the γ-amino buturic acid (GABA transporter inhibitor NNC 711, SVS induced an increase in GABA to 150±15% of baseline in the substantia nigra (SN of unlesioned animals, but had no effect in the pedunculopontine nucleus (PPN, the striatum or the ventromedial thalamus (VM. Dopamine release remained stable in all areas, as did GABA and amine concentrations in the SN of unstimulated controls. Following SVS, a sustained increase in GABA concentrations was observed in the ipsilesional, but not in the contralesional SN of 6-OHDA hemilesioned rats. In contrast, L-DOPA treatment produced a similar increase of GABA in the ipsi- and contra-lesional SN. CONCLUSIONS/SIGNIFICANCE: SVS improves rod performance in a rat model of Parkinson's disease, possibly by increasing nigral GABA release in a dopamine independent way. We propose that SVS could be useful for

  11. Parkinson's Disease and Neurodegeneration: GABA-Collapse Hypothesis

    Science.gov (United States)

    Błaszczyk, Janusz W.

    2016-01-01

    Neurodegenerative diseases constitute a heterogeneous group of age-related disorders that are characterized by a slow but irreversible deterioration of brain functions. Evidence accumulated over more than two decades has implicated calcium-related homeostatic mechanisms, giving rise to the Ca2+ hypothesis of brain aging and, ultimately, cell death. Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter within the central (CNS), peripheral and enteric nervous systems. It appears to be involved in a wide variety of physiological functions within and outside the nervous system, that are maintained through a complex interaction between GABA and calcium-dependent neurotransmission and cellular metabolic functions. Within CNS the Ca2+/GABA mechanism stabilizes neuronal activity both at cellular and systemic levels. Decline in the Ca2+/GABA control initiates several cascading processes leading to both weakened protective barriers (in particular the blood-brain barrier) and accumulations of intracellular deposits of calcium and Lewy bodies. Linking such a vital mechanism of synaptic transmission with metabolism (both at cellular and tissue level) by means of a common reciprocal Ca2+/GABA inhibition results in a fragile balance, which is prone to destabilization and auto-destruction. The GABA decline etiology proposed here appears to apply to all human neurodegenerative processes initiated by abnormal intracellular calcium levels. Therefore, the original description of Parkinson's disease (PD) as due to the selective damage of dopaminergic neurons in the mesencephalon should be updated into the concept of a severe multisystemic neurodegenerative disorder of the nervous system, whose clinical symptoms reflect the localization and progression of the most advanced GABA pathology. A future and more complete therapeutic approach to PD should be aimed first at slowing (or stopping) the progression of Ca2+/GABA functional decline. PMID:27375426

  12. New GABA amides activating GABA A-receptors

    OpenAIRE

    Peter Raster; Andreas Späth; Svetlana Bultakova; Pau Gorostiza; Burkhard König; Piotr Bregestovski

    2013-01-01

    We have prepared a series of new and some literature-reported GABA-amides and determined their effect on the activation of GABAA-receptors expressed in CHO cells. Special attention was paid to the purification of the target compounds to remove even traces of GABA contaminations, which may arise from deprotection steps in the synthesis. GABA-amides were previously reported to be partial, full or superagonists. In our hands these compounds were not able to activate GABAA-receptor channels in wh...

  13. GABA Metabolism and Transport: Effects on Synaptic Efficacy

    Directory of Open Access Journals (Sweden)

    Fabian C. Roth

    2012-01-01

    Full Text Available GABAergic inhibition is an important regulator of excitability in neuronal networks. In addition, inhibitory synaptic signals contribute crucially to the organization of spatiotemporal patterns of network activity, especially during coherent oscillations. In order to maintain stable network states, the release of GABA by interneurons must be plastic in timing and amount. This homeostatic regulation is achieved by several pre- and postsynaptic mechanisms and is triggered by various activity-dependent local signals such as excitatory input or ambient levels of neurotransmitters. Here, we review findings on the availability of GABA for release at presynaptic terminals of interneurons. Presynaptic GABA content seems to be an important determinant of inhibitory efficacy and can be differentially regulated by changing synthesis, transport, and degradation of GABA or related molecules. We will discuss the functional impact of such regulations on neuronal network patterns and, finally, point towards pharmacological approaches targeting these processes.

  14. Reduced tonic inhibition in striatal output neurons from Huntington mice due to loss of astrocytic GABA release through GAT-3

    Directory of Open Access Journals (Sweden)

    Anna Maria Wójtowicz

    2013-11-01

    Full Text Available The extracellular concentration of the two main neurotransmitters glutamate and GABA is low but not negligible which enables a number of tonic actions. The effects of ambient GABA vary in a region-, cell-type and age-dependent manner and can serve as indicators of disease-related alterations. Here we explored the tonic inhibitory actions of GABA in Huntington's disease (HD. HD is a devastating neurodegenerative disorder caused by a mutation in the huntingtin gene. Whole cell patch clamp recordings from striatal output neurons (SONs in slices from adult wild type mice and two mouse models of HD (Z_Q175_KI homozygotes or R6/2 heterozygotes revealed an HD-related reduction of the GABA(A receptor-mediated tonic chloride current (ITonic(GABA along with signs of reduced GABA(B receptor-mediated presynaptic depression of synaptic GABA release. About half of ITonic(GABA depended on tetrodotoxin-sensitive synaptic GABA release, but the remaining current was still lower in HD. Both in WT and HD, ITonic(GABA was more prominent during the first four hours after preparing the slices, when astrocytes but not neurons exhibited a transient depolarization. All further tests were performed within 1 to 4 h in vitro. Experiments with SNAP5114, a blocker of the astrocytic GABA transporter GAT-3, suggest that in WT but not HD GAT-3 operated in the releasing mode. Application of a transportable substrate for glutamate transporters (D-aspartate 0.1 - 1 mM restored the non-synaptic GABA release in slices from HD mice. ITonic(GABA was also rescued by applying the hyperagonist gaboxadol (0.33 µM. The results lead to the hypothesis that lesion-induced astrocyte depolarization facilitates nonsynaptic release of GABA through GAT-3. However, the capacity of depolarized astrocytes to provide GABA for tonic inhibition is strongly reduced in HD.

  15. Localization of glycine, GABA and neuropeptide containing neurons in tiger salamander retina

    International Nuclear Information System (INIS)

    Putative glycinergic and GABAergic neurons in the salamander retina were localized by a parallel analysis of high affinity 3H-glycine uptake and glycine-like immunoreactivity (Gly-IR) and a comparative analysis of high affinity 3H-GABA uptake, GABA, like immunoreactivity (GABA-IR), and glutamate decarboxylase immunoreactivity (GAD-IR) at the light microscopic level. Good correspondence of labeling of 3H-glycine uptake and Gly-IR as well as that of 3H-GABA uptake and GABA-IR were observed. In addition, GAD immunoreactive neurons contained GABA-IR as well. Extensive colocalization of 3H-glycine uptake and Gly-IR and that of 3H-GABA uptake, GABA-IR and perhaps GAD-IR were indicated by the similarities in the distribution, morphology and labeling frequency of neurons and lamination in the inner plexiform layer (IPL). However, the Gly-IR and the GABA-IR probes appeared to be more sensitive and can thus be a reliable marker for glycine and GABA containing neurons respectively

  16. Impairment of GABA transporter GAT-1 terminates cortical recurrent network activity via enhanced phasic inhibition

    Directory of Open Access Journals (Sweden)

    David Johannes Hawellek

    2013-09-01

    Full Text Available In the central nervous system, GABA transporters (GATs very efficiently clear synaptically released GABA from the extracellular space, and thus exert a tight control on GABAergic inhibition. In neocortex, GABAergic inhibition is heavily recruited during recurrent phases of spontaneous action potential activity which alternate with neuronally quiet periods. Therefore, such activity should be quite sensitive to minute alterations of GAT function. Here, we explored the effects of a gradual impairment of GAT-1 and GAT-2/3 on spontaneous recurrent network activity – termed network bursts and silent periods – in organotypic slice cultures of rat neocortex. The GAT-1 specific antagonist NO-711 depressed activity already at nanomolar concentrations (IC50 for depression of spontaneous multiunit firing rate of 42 nM, reaching a level of 80% at 500-1000 nM. By contrast, the GAT-2/3 preferring antagonist SNAP-5114 had weaker and less consistent effects. Several lines of evidence pointed towards an enhancement of phasic GABAergic inhibition as the dominant activity-depressing mechanism: network bursts were drastically shortened, phasic GABAergic currents decayed slower, and neuronal excitability during ongoing activity was diminished. In silent periods, NO-711 had little effect on neuronal excitability or membrane resistance, quite in contrast to the effects of muscimol, a GABA mimetic which activates GABAA receptors tonically. Our results suggest that an enhancement of phasic GABAergic inhibition efficiently curtails cortical recurrent activity and may mediate antiepileptic effects of therapeutically relevant concentrations of GAT-1 antagonists.

  17. A fluorescence-coupled assay for gamma aminobutyric acid (GABA reveals metabolic stress-induced modulation of GABA content in neuroendocrine cancer.

    Directory of Open Access Journals (Sweden)

    Joseph E Ippolito

    Full Text Available Pathways involved in the synthesis of the neurotransmitter gamma-aminobutyric acid (GABA have been implicated in the pathogenesis of high grade neuroendocrine (NE neoplasms as well as neoplasms from a non-NE lineage. Using The Cancer Genome Atlas, overexpression of the GABA synthetic enzyme, glutamate decarboxylase 1 (GAD1, was found to be associated with decreased disease free-survival in prostate adenocarcinoma and decreased overall survival in clear cell renal cell carcinomas. Furthermore, GAD1 was found to be expressed in castrate-resistant prostate cancer cell lines, but not androgen-responsive cell lines. Using a novel fluorescence-coupled enzymatic microplate assay for GABA mediated through reduction of resazurin in a prostate neuroendocrine carcinoma (PNEC cell line, acid microenvironment-induced stress increased GABA levels while alkaline microenvironment-induced stress decreased GABA through modulation of GAD1 and glutamine synthetase (GLUL activities. Moreover, glutamine but not glucose deprivation decreased GABA through modulation of GLUL. Consistent with evidence in prokaryotic and eukaryotic organisms that GABA synthesis mediated through GAD1 may play a crucial role in surviving stress, GABA may be an important mediator of stress survival in neoplasms. These findings identify GABA synthesis and metabolism as a potentially important pathway for regulating cancer cell stress response as well as a potential target for therapeutic strategies.

  18. Caterpillar feeding responses to sorghum leaves with altered lignin levels

    Science.gov (United States)

    Production of liquid fuels from biomass is impeded by the presence of lignin. Plants with lower or altered lignin are more amenable to lignocellulosic conversion to ethanol and other biofuels, but may be more susceptible to insect damage where lignin is an important resistance factor. Sorghum, Sorg...

  19. Disorders of GABA metabolism: SSADH and GABA-transaminase deficiencies

    OpenAIRE

    Parviz, Mahsa; Vogel, Kara; Gibson, K Michael; Pearl, Phillip L.

    2014-01-01

    Clinical disorders known to affect inherited gamma-amino butyric acid (GABA) metabolism are autosomal recessively inherited succinic semialdehyde dehydrogenase and GABA-transaminase deficiency. The clinical presentation of succinic semialdehyde dehydrogenase deficiency includes intellectual disability, ataxia, obsessive-compulsive disorder and epilepsy with a nonprogressive course in typical cases, although a progressive form in early childhood as well as deterioration in adulthood with worse...

  20. Glutamate, GABA, and glutamine are synchronously upregulated in the mouse lateral septum during the postpartum period.

    Science.gov (United States)

    Zhao, Changjiu; Gammie, Stephen C

    2014-12-01

    Dramatic structural and functional remodeling occurs in the postpartum brain for the establishment of maternal care, which is essential for the growth and development of young offspring. Glutamate and GABA signaling are critically important in modulating multiple behavioral performances. Large scale signaling changes occur in the postpartum brain, but it is still not clear to what extent the neurotransmitters glutamate and GABA change and whether the ratio of glutamate/GABA remains balanced. In this study, we examined the glutamate/GABA-glutamine cycle in the lateral septum (LS) of postpartum female mice. In postpartum females (relative to virgins), tissue levels of glutamate and GABA were elevated in LS and increased mRNA was found for the respective enzymes producing glutamate and GABA, glutaminase (Gls) and glutamate decarboxylase 1 and 2 (Gad1 and Gad2). The common precursor, glutamine, was elevated as was the enzyme that produces it, glutamate-ammonia ligase (Glul). Additionally, glutamate, GABA, and glutamine were positively correlated and the glutamate/GABA ratio was almost identical in the postpartum and virgin females. Collectively, these findings indicate that glutamate and GABA signaling are increased and that the ratio of glutamate/GABA is well balanced in the maternal LS. The postpartum brain may provide a useful model system for understanding how glutamate and GABA are linked despite large signaling changes. Given that some mental health disorders, including depression and schizophrenia display dysregulated glutamate/GABA ratio, and there is increased vulnerability to mental disorders in mothers, it is possible that these postpartum disorders emerge when glutamate and GABA changes are not properly coordinated. PMID:25451092

  1. Reduced tonic inhibition in striatal output neurons from Huntington mice due to loss of astrocytic GABA release through GAT-3

    OpenAIRE

    Wójtowicz, Anna M.; Dvorzhak, Anton; Semtner, Marcus; Grantyn, Rosemarie

    2013-01-01

    The extracellular concentration of the two main neurotransmitters glutamate and GABA is low but not negligible which enables a number of tonic actions. The effects of ambient GABA vary in a region-, cell-type, and age-dependent manner and can serve as indicators of disease-related alterations. Here we explored the tonic inhibitory actions of GABA in Huntington's disease (HD). HD is a devastating neurodegenerative disorder caused by a mutation in the huntingtin gene. Whole cell patch clamp rec...

  2. GABA and human spermatozoa : characterization and regulation of GABA transport proteins

    OpenAIRE

    Aanesen, Arthur

    1998-01-01

    The present project aimed at investigating the interaction between GABA and human spermatozoa under in vitro conditions. Our initial hypothesis was that human spermatozoa had specific binding proteins for GABA and that the binding of GABA to such binding sites could affect sperm fimction. Studies on swim-up preparations of human spermatozoa incubated with radiolabelled GABA in the presence of unlabelled GABA, alternatively displacers of GABAA/B receptors and GABA transpo...

  3. GABA(A) receptor downregulation in brains of subjects with autism.

    Science.gov (United States)

    Fatemi, S Hossein; Reutiman, Teri J; Folsom, Timothy D; Thuras, Paul D

    2009-02-01

    Gamma-aminobutyric acid A (GABA(A)) receptors are ligand-gated ion channels responsible for mediation of fast inhibitory action of GABA in the brain. Preliminary reports have demonstrated altered expression of GABA receptors in the brains of subjects with autism suggesting GABA/glutamate system dysregulation. We investigated the expression of four GABA(A) receptor subunits and observed significant reductions in GABRA1, GABRA2, GABRA3, and GABRB3 in parietal cortex (Brodmann's Area 40 (BA40)), while GABRA1 and GABRB3 were significantly altered in cerebellum, and GABRA1 was significantly altered in superior frontal cortex (BA9). The presence of seizure disorder did not have a significant impact on GABA(A) receptor subunit expression in the three brain areas. Our results demonstrate that GABA(A) receptors are reduced in three brain regions that have previously been implicated in the pathogenesis of autism, suggesting widespread GABAergic dysfunction in the brains of subjects with autism. PMID:18821008

  4. Perisynaptic GABA Receptors: The Overzealous Protector

    Directory of Open Access Journals (Sweden)

    Andrew N. Clarkson

    2012-01-01

    Full Text Available An attempt to find pharmacological therapies to treat stroke patients and minimize the extent of cell death has seen the failure of dozens of clinical trials. As a result, stroke/cerebral ischemia is the leading cause of lasting adult disability. Stroke-induced cell death occurs due to an excess release of glutamate. As a consequence to this, a compensatory increased release of GABA occurs that results in the subsequent internalization of synaptic GABAA receptors and spillover onto perisynaptic GABAA receptors, resulting in increased tonic inhibition. Recent studies show that the brain can engage in a limited process of neural repair after stroke. Changes in cortical sensory and motor maps and alterations in axonal structure are dependent on patterned neuronal activity. It has been assumed that changes in neuronal excitability underlie processes of neural repair and remapping of cortical sensory and motor representations. Indeed, recent evidence suggests that local inhibitory and excitatory currents are altered after stroke and modulation of these networks to enhance excitability during the repair phase can facilitate functional recovery after stroke. More specifically, dampening tonic GABA inhibition can afford an early and robust improvement in functional recovery after stroke.

  5. Brain glycogen and its role in supporting glutamate and GABA homeostasis in a type 2 diabetes rat model

    DEFF Research Database (Denmark)

    Sickmann, Helle Mark; Waagepetersen, Helle S.; Schousboe, Arne;

    2012-01-01

    diabetic state. Also, our objective was to elucidate the contribution of glycogen to support neurotransmitter glutamate and GABA homeostasis. A glycogen phosphorylase (GP) inhibitor was administered to Sprague-Dawley (SprD) and Zucker Diabetic Fatty (ZDF) rats in vivo and after one day of treatment [1......-(13)C]glucose was used to monitor metabolism. Brain levels of (13)C labeling in glucose, lactate, alanine, glutamate, GABA, glutamine and aspartate were determined. Our results show that inhibition of brain glycogen metabolism reduced the amounts of glutamate in both the control and type 2 diabetes......The number of people suffering from diabetes is hastily increasing and the condition is associated with altered brain glucose homeostasis. Brain glycogen is located in astrocytes and being a carbohydrate reservoir it contributes to glucose homeostasis. Furthermore, glycogen has been indicated to be...

  6. GR3027 antagonizes GABA(A) receptor-potentiating neurosteroids and restores spatial learning and motor coordination in rats with chronic hyperammonemia and hepatic encephalopathy

    OpenAIRE

    Johansson, Maja; Agusti, Ana; Llansola, Marta; Montoliu, Carmina; Strömberg, Jessica; Malinina, Evgenya; Ragagnin, Gianna; Doverskog, Magnus; Bäckström, Torbjörn; Felipo, Vicente

    2015-01-01

    Hepatic encephalopathy (HE) is one of the primary complications of liver cirrhosis. Current treatments for HE, mainly directed to reduction of ammonia levels, are not effective enough because they cannot completely eliminate hyperammonemia and inflammation, which induce the neurological alterations. Studies in animal models show that overactivation of GABA(A) receptors is involved in cognitive and motor impairment in HE and that reducing this activation restores these functions. We have devel...

  7. An analysis of [3H]gamma-aminobutyric acid (GABA) binding in the human brain.

    Science.gov (United States)

    Lloyd, K G; Dreksler, S

    1979-03-01

    The binding of [3H]GABA to membranes prepared from human brains obtained post morten was examined. This binding was independent of patient sex, age (16--80 years), postmortem interval (4--33 h) or storage time when frozen (0-64 months). In preparations from cerebellar cortex various compounds displaced [3H]GABA binding with the following order of potency: muscimol greater than 3-aminopropanesulfonic acid greater than GABA greater than imidazoleacet acid greater than delta-amino-n-valeric acid greater than 3-hydroxyGABA greater than bicuculline. Other compounds active 'in vitro' included strychnine, homocarnosine and some (e.g. clozapine, thioridazine, pimozide) but not all (chlorpromazine, haloperiodol) neuroleptics. Compounds inactive 'in vitro' included aminooxyacetic acid, baclofen, picrotoxin, anticholinergics, metrazole, anticonvulsants and naloxone. Triton X-100 augmented the [3H]GABA binding (25 nM) by about 10--20-fold in most brain regions. [3H]GABA binding (IC50) was altered in Huntington's chorea and Reye's syndrome, but not in schizophrenics (4-neuroleptic-treated patients) or sudden infant death syndrome. The data presented strongly support the proposal that the measurement of [3H]GABA binding in postmortem human brain offers a reflection of the state of the physiologically relevant GABA receptor. PMID:218679

  8. Immature Responses to GABA in Fragile X Neurons Derived from Human Embryonic Stem Cells

    Science.gov (United States)

    Telias, Michael; Segal, Menahem; Ben-Yosef, Dalit

    2016-01-01

    Fragile X Syndrome (FXS) is the most common form of inherited cognitive disability. However, functional deficiencies in FX neurons have been described so far almost exclusively in animal models. In a recent study we found several functional deficits in FX neurons differentiated in-vitro from human embryonic stem cells (hESCs), including their inability to fire repetitive action potentials, and their lack of synaptic activity. Here, we investigated the responses of such neurons to pulse application of the neurotransmitter GABA. We found two distinct types of responses to GABA and sensitivity to the GABA-A receptor antagonist bicuculline; type 1 (mature) characterized by non-desensitized responses to GABA as well as a high sensitivity to bicuculline, and type 2 (immature) which are desensitized to GABA and insensitive to bicuculline. Type 1 responses were age-dependent and dominant in mature WT neurons. In contrast, FX neurons expressed primarily type 2 phenotype. Expression analysis of GABA-A receptor subunits demonstrated that this bias in human FX neurons was associated with a significant alteration in the expression pattern of the GABA-A receptor subunits α2 and β2. Our results indicate that FMRP may play a role in the development of the GABAergic synapse during neurogenesis. This is the first demonstration of the lack of a mature response to GABA in human FX neurons and may explain the inappropriate synaptic functions in FXS. PMID:27242433

  9. Alterations in blood glucose levels under hyperinsulinemia affect accumbens dopamine

    OpenAIRE

    Bello, Nicholas T.; Hajnal, Andras

    2006-01-01

    Dopaminergic systems have been implicated in diabetes and obesity. Notwithstanding, the most basic relationship between dopamine and plasma insulin as well as glucose levels yet remains unknown. The present experiments were designed to investigate the effects of acute hyperinsulinemia on basal dopamine levels in the nucleus accumbens of the rat under chloral hydrate anesthesia using acute microdialysis in combination with the hyperinsulinemic-glycemic clamping procedure. In Experiment 1, each...

  10. Light-Induced Alterations in Basil Ganglia Kynurenic Acid Levels

    Science.gov (United States)

    Sroufe, Angela E.; Whittaker, J. A.; Patrickson, J. W.; Orr, M. C.

    1997-01-01

    The metabolic synthesis, release and breakdown of several known CNS neurotransmitters have been shown to follow a circadian pattern entrained to the environmental light/dark cycle. The levels of excitatory amino acid (EAA) transmitters such as glutamate, have been shown to vary with environmental lighting conditions. Kynurenic Acid (KA), an endogenous tryptophan metabolite and glutamate receptor antagonist, has been reported to have neuroprotective effects against EAA-induced excitotoxic cell damage. Changes in KA's activity within the mammalian basal ganglia has been proposed as being contributory to neurotoxicity in Huntington's Disease. It is not known whether CNS KA levels follow a circadian pattern or exhibit light-induced fluctuations. However, because the symptoms of certain degenerative motor disorders seem to fluctuate with daily 24 hour rhythm, we initiated studies to determine if basal ganglia KA were influenced by the daily light/dark cycle and could influence motor function. Therefore in this study, HPLC-EC was utilized to determine if basal ganglia KA levels in tissue extracts from adult male Long-Evans rats (200-250g) entrained to 24 and 48 hours constant light and dark conditions, respectively. Samples were taken one hour before the onset of the subjective day and one hour prior to the onset of the subjective night in order to detect possible phase differences in KA levels and to allow for accumulation of factors expressed in association with the light or dark phase. Data analysis revealed that KA levels in the basal ganglia vary with environmental lighting conditions; being elevated generally during the dark. Circadian phase differences in KA levels were also evident during the subjective night and subjective day, respectively. Results from these studies are discussed with respect to potential cyclic changes in neuronal susceptibility to excitotoxic damage during the daily 24 hour cycle and its possible relevance to future therapeutic approaches in

  11. The Subcellular Localization of GABA Transporters and Its Implication for Seizure Management

    DEFF Research Database (Denmark)

    Madsen, Karsten K; Hansen, Gert H; Danielsen, E Michael; Schousboe, Arne

    2015-01-01

    [d]isoxazol-3-ol (EF1502) which not only inhibits GAT1 like tiagabine but also BGT1 has been shown to modulate extrasynaptic GABA levels. The simultaneous inhibition of synaptic and extrasynaptic GABA transporters using tiagabine and EF1502, respectively has been demonstrated to exert a synergistic...

  12. Functional properties of GABA synaptic inputs onto GABA neurons in monkey prefrontal cortex

    NARCIS (Netherlands)

    D.C. Rotaru (Diana C.); C. Olezene (Cameron); T. Miyamae (Takeaki); N.V. Povysheva (Nadezhda V.); A.V. Zaitsev (Aleksey V.); D.A. Lewis (David A.); G. Gonzalez-Burgos (Guillermo)

    2015-01-01

    textabstractIn rodent cortex GABAA receptor (GABAAR)-mediated synapses are a significant source of input onto GABA neurons, and the properties of these inputs vary among GABA neuron subtypes that differ in molecular markers and firing patterns. Some features of cortical interne

  13. Alterations in Plasma Amino Acid Levels in Chronic Pancreatitis

    Directory of Open Access Journals (Sweden)

    Banavara Narasimhamurthy Girish

    2011-01-01

    Full Text Available Context Dietary proteins and amino acids can modulate pancreatic function. Objective Our aim was to estimate the levels of plasma amino acids in chronic pancreatitis patients and study their relationship with disease characteristics as well as exocrine and endocrine insufficiency. Patients One hundred and seventy-five consecutive adult patients with chronic pancreatitis: 84 patients with alcoholic chronic pancreatitis and 91 patients with tropical chronic pancreatitis. One hundred and thirteen healthy controls were also studied. Design Prospective study. Main outcome measures Disease characteristics and imaging features were recorded. Plasma-free amino acid levels were estimated using reverse-phase high-performance liquid chromatography. Polyclonal antibody ELISA was used to assess pancreatic fecal elastase-1. Results The majority of the plasma free amino acid levels decreased in chronic pancreatitis patients whereas glutamate, glycine, proline and lysine were elevated as compared to the controls. Multivariate logistic regression analysis revealed that the decrease in branched chain amino acid concentration was significantly associated with the presence of diabetes and low fecal elastase-1. In addition, a significant positive correlation was observed between branched chain amino acids and pancreatic elastase-1 (rs=0.724, P

  14. Alteration of serum estrogen levels in pregnant mares

    International Nuclear Information System (INIS)

    The estrogen levels in the peripheral blood serum of 5 mares were estimated by readioimmunoassay throughout their gestation period. Blood samples were collected from jugular veins, and the radioimmunoassay method, originated by Makino, had sufficient accuracy and reliability for the estimation. The result obtained was summarized as follows. The serum concentration of E, remained below 40 pg/ml from Day 0 to Day 75, then increased to 190.5 pg/ml on Day 120, and sharply up to the average value of 3682.2 pg/ml on Day 210, and the high levels continued for about a month. It then declined sharply towards 107.9 pg/ml on Day 300, with the fluctuation around Day 255 to 270. The E2 concentration showed the similar pattern to that of E1: it remained below 15.2 pg/ml from Day 0 to Day 75, 46.5 pg/ml on Day 120, then began to increase rather sharply up to Day 210, and the average highest value obtained was 1740.6 pg/ml. From around Day 210, the average E2 concentration remained high for about 2 months, then it declined sharply to 71.3 pg/ml on Day 285. The E3 level showed large variation within and among individuals, and no correlation was observed throughout the gestation period. (Kobatake, H.)

  15. Downregulation of GABA[Subscript A] Receptor Protein Subunits a6, ß2, d, e, ?2, ?, and ?2 in Superior Frontal Cortex of Subjects with Autism

    Science.gov (United States)

    Fatemi, S. Hossein; Reutiman, Teri J.; Folsom, Timothy D.; Rustan, Oyvind G.; Rooney, Robert J.; Thuras, Paul D.

    2014-01-01

    We measured protein and mRNA levels for nine gamma-aminobutyric acid A (GABA[subscript A]) receptor subunits in three brain regions (cerebellum, superior frontal cortex, and parietal cortex) in subjects with autism versus matched controls. We observed changes in mRNA for a number of GABA[subscript A] and GABA[subscript B] subunits and overall…

  16. Segregation of acetylcholine and GABA in the rat superior cervical ganglia: functional correlation.

    Directory of Open Access Journals (Sweden)

    Diana eElinos

    2016-04-01

    Full Text Available Sympathetic neurons have the capability to segregate their neurotransmitters (NTs and co-transmitters to separate varicosities of single axons; furthermore, in culture, these neurons can even segregate classical transmitters. In vivo sympathetic neurons employ acetylcholine (ACh and other classical NTs such as gamma aminobutyric acid (GABA. Herein, we explore whether these neurons in vivo segregate these classical NTs in the superior cervical ganglia of the rat. We determined the topographical distribution of GABAergic varicosities, somatic GABAA receptor, as well as the regional distribution of the segregation of ACh and GABA. We evaluated possible regional differences in efficacy of ganglionic synaptic transmission, in the sensitivity of GABAA receptor to GABA and to the competitive antagonist picrotoxin (PTX. We found that sympathetic preganglionic neurons in vivo do segregate ACh and GABA. GABAergic varicosities and GABAA receptor expression showed a rostro-caudal gradient along ganglia; in contrast, segregation exhibited a caudo-rostral gradient. These uneven regional distributions in expression of GABA, GABAA receptors, and level segregation correlate with stronger synaptic transmission found in the caudal region. Accordingly, GABAA receptors of rostral region show larger sensitivity to GABA and PTX. These results suggest the presence of different types of GABAA receptors in each region that result in a different regional levels of endogenous GABA inhibition. Finally, we discuss a possible correlation of these different levels of GABA modulation and the function of the target organs innervated by rostral and caudal ganglionic neurons.

  17. Segregation of Acetylcholine and GABA in the Rat Superior Cervical Ganglia: Functional Correlation

    Science.gov (United States)

    Elinos, Diana; Rodríguez, Raúl; Martínez, Luis Andres; Zetina, María Elena; Cifuentes, Fredy; Morales, Miguel Angel

    2016-01-01

    Sympathetic neurons have the capability to segregate their neurotransmitters (NTs) and co-transmitters to separate varicosities of single axons; furthermore, in culture, these neurons can even segregate classical transmitters. In vivo sympathetic neurons employ acetylcholine (ACh) and other classical NTs such as gamma aminobutyric acid (GABA). Herein, we explore whether these neurons in vivo segregate these classical NTs in the superior cervical ganglia of the rat. We determined the topographical distribution of GABAergic varicosities, somatic GABAA receptor, as well as the regional distribution of the segregation of ACh and GABA. We evaluated possible regional differences in efficacy of ganglionic synaptic transmission, in the sensitivity of GABAA receptor to GABA and to the competitive antagonist picrotoxin (PTX). We found that sympathetic preganglionic neurons in vivo do segregate ACh and GABA. GABAergic varicosities and GABAA receptor expression showed a rostro-caudal gradient along ganglia; in contrast, segregation exhibited a caudo-rostral gradient. These uneven regional distributions in expression of GABA, GABAA receptors, and level of segregation correlate with stronger synaptic transmission found in the caudal region. Accordingly, GABAA receptors of rostral region showed larger sensitivity to GABA and PTX. These results suggest the presence of different types of GABAA receptors in each region that result in a different regional levels of endogenous GABA inhibition. Finally, we discuss a possible correlation of these different levels of GABA modulation and the function of the target organs innervated by rostral and caudal ganglionic neurons. PMID:27092054

  18. Segregation of Acetylcholine and GABA in the Rat Superior Cervical Ganglia: Functional Correlation.

    Science.gov (United States)

    Elinos, Diana; Rodríguez, Raúl; Martínez, Luis Andres; Zetina, María Elena; Cifuentes, Fredy; Morales, Miguel Angel

    2016-01-01

    Sympathetic neurons have the capability to segregate their neurotransmitters (NTs) and co-transmitters to separate varicosities of single axons; furthermore, in culture, these neurons can even segregate classical transmitters. In vivo sympathetic neurons employ acetylcholine (ACh) and other classical NTs such as gamma aminobutyric acid (GABA). Herein, we explore whether these neurons in vivo segregate these classical NTs in the superior cervical ganglia of the rat. We determined the topographical distribution of GABAergic varicosities, somatic GABAA receptor, as well as the regional distribution of the segregation of ACh and GABA. We evaluated possible regional differences in efficacy of ganglionic synaptic transmission, in the sensitivity of GABAA receptor to GABA and to the competitive antagonist picrotoxin (PTX). We found that sympathetic preganglionic neurons in vivo do segregate ACh and GABA. GABAergic varicosities and GABAA receptor expression showed a rostro-caudal gradient along ganglia; in contrast, segregation exhibited a caudo-rostral gradient. These uneven regional distributions in expression of GABA, GABAA receptors, and level of segregation correlate with stronger synaptic transmission found in the caudal region. Accordingly, GABAA receptors of rostral region showed larger sensitivity to GABA and PTX. These results suggest the presence of different types of GABAA receptors in each region that result in a different regional levels of endogenous GABA inhibition. Finally, we discuss a possible correlation of these different levels of GABA modulation and the function of the target organs innervated by rostral and caudal ganglionic neurons. PMID:27092054

  19. Effect of GABA on oxidative stress in the skeletal muscles and plasma free amino acids in mice fed high-fat diet.

    Science.gov (United States)

    Xie, Z X; Xia, S F; Qiao, Y; Shi, Y H; Le, G W

    2015-06-01

    Increased levels of plasma free amino acids (pFAAs) can disturb the blood glucose levels in patients with obesity, diabetes mellitus and metabolic syndrome (MS) and are associated with enhanced protein oxidation. Oxidation of proteins, especially in the muscles, can promote protein degradation and elevate the levels of pFAAs. Gamma-aminobutyric acid (GABA), a food additive, can reduce high-fat diet (HFD)-induced hyperglycaemia; however, the mechanisms remain unclear. The aim of this study was to evaluate the effects of GABA on protein oxidation and pFAAs changes. One hundred male C57BL/6 mice were randomly divided into five groups that were fed with control diet, HFD and HFD supplied with 0.2%, 0.12% and 0.06% GABA in drinking water for 20 weeks respectively. HFD feeding led to muscular oxidative stress, protein oxidation, pFAA disorders, hyperglycaemia and augmented plasma GABA levels. Treatment with GABA restored normally fasting blood glucose level and dose-dependently inhibited body weight gains, muscular oxidation and protein degradation. While medium and low doses of GABA mitigated HFD-induced pFAA disorders, the high dose of GABA deteriorated the pFAA disorders. Medium dose of GABA increased the levels of GABA, but high dose of GABA reduced the levels of plasma GABA and increased the activity of succinic semialdehyde dehydrogenase in the liver. Therefore, treatment with GABA mitigated HFD-induced hyperglycaemia probably by repairing HFD-induced muscular oxidative stress and pFAA disorders in mice. Our data also suggest that an optimal dose of GABA is crucial for the prevention of excess GABA-related decrease in the levels of pFAA and GABA as well as obesity. PMID:25266692

  20. GABA, a natural immunomodulator of T lymphocytes

    DEFF Research Database (Denmark)

    Bjurstöm, Helen; Wang, Junyang; Ericsson, Ida;

    2008-01-01

    gamma-aminobutyric acid (GABA) is the main neuroinhibitory transmitter in the brain. Here we show that GABA in the extracellular space may affect the fate of pathogenic T lymphocytes entering the brain. We examined in encephalitogenic T cells if they expressed functional GABA channels that could be...

  1. Synaptic GABA release prevents GABA transporter type-1 reversal during excessive network activity

    OpenAIRE

    Savtchenko, L.; Megalogeni, M.; Rusakov, D. A.; Walker, M. C.; Pavlov, I.

    2015-01-01

    GABA transporters control extracellular GABA, which regulates the key aspects of neuronal and network behaviour. A prevailing view is that modest neuronal depolarization results in GABA transporter type-1 (GAT-1) reversal causing non-vesicular GABA release into the extracellular space during intense network activity. This has important implications for GABA uptake-targeting therapies. Here we combined a realistic kinetic model of GAT-1 with experimental measurements of tonic GABAA receptor cu...

  2. Alteration in serum osteocalcin levels in patients with diabetic nephropathy

    International Nuclear Information System (INIS)

    The fact that bone mass density (BMD) is not useful for assessing fracture risk in diabetic patients (DM) seems problematic, because those populations are increasing in every country. Osteocalcin (OC) is synthesized by osteoblasts and is considered to be a marker of bone formation. The present study was carried out to evaluate the usefulness of OC as noninvasive biomarker of bone formation in diabetes mellitus type 2 (uncomplicated) and diabetic nephropathy. Immunoradiometric assay(IRMA) was used for the quantitative measurement of human intact OC both N-terminal and C-terminal fragments in the serum of the control and the studied groups. OC levels in the uncomplicated diabetic group were significantly lower while in the diabetic nephropathy group was significantly higher compared to control values . There was a weak negative correlation between OC and both fasting blood glucose and glycated Hb% in the diabetic group. In diabetic nephropathy patients, a weak positive correlation was observed between OC and protein creatinine ratio. The results concluded that changes in bone remodelling marker OC are present in both DM type 2 and diabetic nephropathy explaining osteopenia and osteoporosis observed in both cases.Therefore, an effective glycaemic control should be the hallmark of prevention and treatment of diabetes mellitus induced osteoporosis

  3. GABA concentration in posterior cingulate cortex predicts putamen response during resting state fMRI.

    Directory of Open Access Journals (Sweden)

    Jorge Arrubla

    Full Text Available The role of neurotransmitters in the activity of resting state networks has been gaining attention and has become a field of research with magnetic resonance spectroscopy (MRS being one of the key techniques. MRS permits the measurement of γ-aminobutyric acid (GABA and glutamate levels, the central biochemical constituents of the excitation-inhibition balance in vivo. The inhibitory effects of GABA in the brain have been largely investigated in relation to the activity of resting state networks in functional magnetic resonance imaging (fMRI. In this study GABA concentration in the posterior cingulate cortex (PCC was measured using single voxel spectra acquired with standard point resolved spectroscopy (PRESS from 20 healthy male volunteers at 3 T. Resting state fMRI was consecutively measured and the values of GABA/Creatine+Phosphocreatine ratio (GABA ratio were included in a general linear model matrix as a step of dual regression analysis in order to identify voxels whose neuroimaging metrics during rest were related to individual levels of the GABA ratio. Our data show that the connection strength of putamen to the default-mode network during resting state has a negative linear relationship with the GABA ratio measured in the PCC. These findings highlight the role of PCC and GABA in segregation of the motor input, which is an inherent condition that characterises resting state.

  4. Modulation of cell surface GABA B receptors by desensitization,trafficking and regulated degradation

    Institute of Scientific and Technical Information of China (English)

    Dietmar; Benke; Khaled; Zemoura; Patrick; J; Maier

    2012-01-01

    Inhibitory neurotransmission ensures normal brain function by counteracting and integrating excitatory activity.-Aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the mammalian central nervous system,and mediates its effects via two classes of receptors:the GABA A and GABA B receptors.GABA A receptors are heteropentameric GABA-gated chloride channels and responsible for fast inhibitory neurotransmission.GABA B receptors are heterodimeric G protein coupled receptors (GPCR) that mediate slow and prolonged inhibitory transmission.The extent of inhibitory neurotransmission is determined by a variety of factors,such as the degree of transmitter release and changes in receptor activity by posttranslational modifications (e.g.,phosphorylation),as well as by the number of receptors present in the plasma membrane available for signal transduction.The level of GABA B receptors at the cell surface critically depends on the residence time at the cell surface and finally the rates of endocytosis and degradation.In this review we focus primarily on recent advances in the understanding of trafficking mechanisms that determine the expression level of GABA B receptors in the plasma membrane,and thereby signaling strength.

  5. GABA System in Schizophrenia and Mood Disorders: A Mini Review on Third-Generation Imaging Studies.

    Science.gov (United States)

    Chiapponi, Chiara; Piras, Federica; Piras, Fabrizio; Caltagirone, Carlo; Spalletta, Gianfranco

    2016-01-01

    Third-generation neuroimaging research has been enriched by advances in magnetic resonance spectroscopy (MRS) measuring the concentration of important neurotrasmitters, such as the inhibitory amino acid GABA. Here, we performed a systematic mini-review on brain MRS studies measuring GABA concentration in patients affected by schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). We wondered whether multimodal investigations could overcome intrinsic technical limits of MRS giving a broader view of mental disorders pathogenesis. In SZ, unimodal studies gave mixed results, as increased, decreased, or unaltered GABA levels were reported depending on region, disease phase, and treatment. Conversely, multimodal results showed reduced level of glutamate, but not of GABA, in patients mirrored by in vitro biochemical findings revealing hippocampal reduction in glutamate signaling in SZ, and no deficits in GABA synthesis. Moreover, a mouse model confirmed the unique pathological characteristic of glutamate function in SZ. Unimodal studies in BD revealed again, inconsistent results, while no multimodal investigations including MRS on GABA exist. In MDD, unimodal studies could not differentiate patients from controls nor characterize high-risk subjects and remitted patients. However, a multimodal study combining functional magnetic resonance imaging and MRS revealed that cingulate cortex activity is related to glutamate, N-acetylaspartate levels and anhedonia in patients, and to GABA concentration in healthy subjects, improving the distinction between MDD and physiology. Overall, our results show that unimodal studies do not indicate GABA as a biomarker for the psychiatric disorders considered. Conversely, multimodal studies can widen the understanding of the link between psychopathology, genetics, neuroanatomy, and functional-biochemical brain activity in mental disorders. Although scarce, multimodal approaches seem promising for moving from GABA MRS

  6. GABA System in Schizophrenia and Mood Disorders: A Mini Review on Third-Generation Imaging Studies

    Science.gov (United States)

    Chiapponi, Chiara; Piras, Federica; Piras, Fabrizio; Caltagirone, Carlo; Spalletta, Gianfranco

    2016-01-01

    Third-generation neuroimaging research has been enriched by advances in magnetic resonance spectroscopy (MRS) measuring the concentration of important neurotrasmitters, such as the inhibitory amino acid GABA. Here, we performed a systematic mini-review on brain MRS studies measuring GABA concentration in patients affected by schizophrenia (SZ), bipolar disorder (BD), and major depressive disorder (MDD). We wondered whether multimodal investigations could overcome intrinsic technical limits of MRS giving a broader view of mental disorders pathogenesis. In SZ, unimodal studies gave mixed results, as increased, decreased, or unaltered GABA levels were reported depending on region, disease phase, and treatment. Conversely, multimodal results showed reduced level of glutamate, but not of GABA, in patients mirrored by in vitro biochemical findings revealing hippocampal reduction in glutamate signaling in SZ, and no deficits in GABA synthesis. Moreover, a mouse model confirmed the unique pathological characteristic of glutamate function in SZ. Unimodal studies in BD revealed again, inconsistent results, while no multimodal investigations including MRS on GABA exist. In MDD, unimodal studies could not differentiate patients from controls nor characterize high-risk subjects and remitted patients. However, a multimodal study combining functional magnetic resonance imaging and MRS revealed that cingulate cortex activity is related to glutamate, N-acetylaspartate levels and anhedonia in patients, and to GABA concentration in healthy subjects, improving the distinction between MDD and physiology. Overall, our results show that unimodal studies do not indicate GABA as a biomarker for the psychiatric disorders considered. Conversely, multimodal studies can widen the understanding of the link between psychopathology, genetics, neuroanatomy, and functional–biochemical brain activity in mental disorders. Although scarce, multimodal approaches seem promising for moving from GABA

  7. GABA system in schizophrenia and mood disorders. A mini review on third generation imaging studies

    Directory of Open Access Journals (Sweden)

    Chiara eChiapponi

    2016-04-01

    Full Text Available Third-generation neuroimaging research has been enriched by advances in magnetic resonance spectroscopy (MRS measuring the concentration of important neurotrasmitters, such as the inhibitory amino acid GABA. Here, we performed a systematic mini-review on brain MRS studies measuring GABA concentration in patients affected by schizophrenia (SZ, bipolar disorder (BD and major depressive disorder (MDD. We wondered whether multimodal investigations could overcome intrinsic technical limits of MRS giving a broader view of mental disorders pathogenesis.In SZ unimodal studies gave mixed results, as increased, decreased or unaltered GABA levels were reported depending on region, disease phase and treatment. Conversely, multimodal results showed reduced level of glutamate, but not of GABA, in patients, mirrored by in vitro biochemical findings revealing hippocampal reduction in glutamate signalling in SZ, and no deficits in GABA synthesis. Moreover, a mouse model confirmed the unique pathological characteristic of glutamate function in SZ.Unimodal studies in BD revealed, again, inconsistent results, while no multimodal investigations including MRS on GABA exist. In MDD, unimodal studies could not differentiate patients from controls, nor characterize high-risk subjects and remitted patients. However, a multimodal study combining functional magnetic resonance imaging and MRS revealed that cingulate cortex activity is related to glutamate and N-acetylaspartate levels and anhedonia in patients, and to GABA concentration in healthy subjects, improving the distinction between MDD and physiology.Overall, our results show that unimodal studies do not indicate GABA as a biomarker for the psychiatric disorders considered. Conversely, multimodal studies can widen the understanding of the link between psychopathology, genetics, neuroanatomy and functional-biochemical brain activity in mental disorders. Although scarce, multimodal approaches seem promising for moving

  8. The glutamate/GABA-glutamine cycle

    DEFF Research Database (Denmark)

    Bak, Lasse K; Schousboe, Arne; Waagepetersen, Helle S

    2006-01-01

    Neurons are metabolically handicapped in the sense that they are not able to perform de novo synthesis of neurotransmitter glutamate and gamma-aminobutyric acid (GABA) from glucose. A metabolite shuttle known as the glutamate/GABA-glutamine cycle describes the release of neurotransmitter glutamate...... or GABA from neurons and subsequent uptake into astrocytes. In return, astrocytes release glutamine to be taken up into neurons for use as neurotransmitter precursor. In this review, the basic properties of the glutamate/GABA-glutamine cycle will be discussed, including aspects of transport and...... metabolism. Discussions of stoichiometry, the relative role of glutamate vs. GABA and pathological conditions affecting the glutamate/GABA-glutamine cycling are presented. Furthermore, a section is devoted to the accompanying ammonia homeostasis of the glutamate/GABA-glutamine cycle, examining the possible...

  9. 3D GABA imaging with real-time motion correction, shim update and reacquisition of adiabatic spiral MRSI

    OpenAIRE

    Bogner, Wolfgang; Gagoski, Borjan; Hess, Aaron T; Bhat, Himanshu; Tisdall, M. Dylan; van der Kouwe, Andre J.W.; Strasser, Bernhard; Marjańska, Małgorzata; Trattnig, Siegfried; Grant, Ellen; Rosen, Bruce; Andronesi, Ovidiu C.

    2014-01-01

    Gamma-aminobutyric acid (GABA) and glutamate (Glu) are the major neurotransmitters in the brain. They are crucial for the functioning of healthy brain and their alteration is a major mechanism in the pathophysiology of many neuro-psychiatric disorders.

  10. Positive regulation by GABA(BR1 subunit of leptin expression through gene transactivation in adipocytes.

    Directory of Open Access Journals (Sweden)

    Yukari Nakamura

    Full Text Available BACKGROUND: The view that γ-aminobutyric acid (GABA plays a functional role in non-neuronal tissues, in addition to an inhibitory neurotransmitter role in the mammalian central nervous system, is prevailing, while little attention has been paid to GABAergic signaling machineries expressed by adipocytes to date. In this study, we attempted to demonstrate the possible functional expression of GABAergic signaling machineries by adipocytes. METHODOLOGY/PRINCIPAL FINDINGS: GABA(B receptor 1 (GABA(BR1 subunit was constitutively expressed by mouse embryonic fibroblasts differentiated into adipocytes and adipocytic 3T3-L1 cells in culture, as well as mouse white adipose tissue, with no responsiveness to GABA(BR ligands. However, no prominent expression was seen with mRNA for GABA(BR2 subunit required for heteromeric orchestration of the functional GABA(BR by any adipocytic cells and tissues. Leptin mRNA expression was significantly and selectively decreased in adipose tissue and embryonic fibroblasts, along with drastically reduced plasma leptin levels, in GABA(BR1-null mice than in wild-type mice. Knockdown by siRNA of GABA(BR1 subunit led to significant decreases in leptin promoter activity and leptin mRNA levels in 3T3-L1 cells. CONCLUSIONS/SIGNIFICANCE: Our results indicate that GABA(BR1 subunit is constitutively expressed by adipocytes to primarily regulate leptin expression at the transcriptional level through a mechanism not relevant to the function as a partner of heterodimeric assembly to the functional GABA(BR.

  11. 7T Proton Magnetic Resonance Spectroscopy of Gamma-Aminobutyric Acid, Glutamate, and Glutamine Reveals Altered Concentrations in Patients With Schizophrenia and Healthy Siblings

    DEFF Research Database (Denmark)

    Thakkar, Katharine N; Rösler, Lara; Wijnen, Jannie P;

    2016-01-01

    BACKGROUND: The N-methyl-D-aspartate receptor hypofunction model of schizophrenia predicts dysfunction in both glutamatergic and gamma-aminobutyric acidergic (GABAergic) transmission. We addressed this hypothesis by measuring GABA, glutamate, glutamine, and the sum of glutamine plus glutamate...... concentrations in vivo in patients with schizophrenia using proton magnetic resonance spectroscopy at 7T, which allows separation of metabolites that would otherwise overlap at lower field strengths. In addition, we investigated whether altered levels of GABA, glutamate, glutamine, and the sum of glutamine plus......, and 24 healthy nonrelatives. Glutamate, glutamine, and GABA were measured cortically and subcortically in bilateral basal ganglia and occipital cortex. RESULTS: Patients with schizophrenia had reduced cortical GABA compared with healthy relatives and the combined sample of healthy relatives and...

  12. Learning-Dependent Plasticity of the Barrel Cortex Is Impaired by Restricting GABA-Ergic Transmission

    Science.gov (United States)

    Posluszny, Anna; Liguz-Lecznar, Monika; Turzynska, Danuta; Zakrzewska, Renata; Bielecki, Maksymilian; Kossut, Malgorzata

    2015-01-01

    Experience-induced plastic changes in the cerebral cortex are accompanied by alterations in excitatory and inhibitory transmission. Increased excitatory drive, necessary for plasticity, precedes the occurrence of plastic change, while decreased inhibitory signaling often facilitates plasticity. However, an increase of inhibitory interactions was noted in some instances of experience-dependent changes. We previously reported an increase in the number of inhibitory markers in the barrel cortex of mice after fear conditioning engaging vibrissae, observed concurrently with enlargement of the cortical representational area of the row of vibrissae receiving conditioned stimulus (CS). We also observed that an increase of GABA level accompanied the conditioning. Here, to find whether unaltered GABAergic signaling is necessary for learning-dependent rewiring in the murine barrel cortex, we locally decreased GABA production in the barrel cortex or reduced transmission through GABAA receptors (GABAARs) at the time of the conditioning. Injections of 3-mercaptopropionic acid (3-MPA), an inhibitor of glutamic acid decarboxylase (GAD), into the barrel cortex prevented learning-induced enlargement of the conditioned vibrissae representation. A similar effect was observed after injection of gabazine, an antagonist of GABAARs. At the behavioral level, consistent conditioned response (cessation of head movements in response to CS) was impaired. These results show that appropriate functioning of the GABAergic system is required for both manifestation of functional cortical representation plasticity and for the development of a conditioned response. PMID:26641862

  13. Dopamine receptor activation modulates GABA neuron migration from the basal forebrain to the cerebral cortex.

    Science.gov (United States)

    Crandall, James E; McCarthy, Deirdre M; Araki, Kiyomi Y; Sims, John R; Ren, Jia-Qian; Bhide, Pradeep G

    2007-04-01

    GABA neurons of the cerebral cortex and other telencephalic structures are produced in the basal forebrain and migrate to their final destinations during the embryonic period. The embryonic basal forebrain is enriched in dopamine and its receptors, creating a favorable environment for dopamine to influence GABA neuron migration. However, whether dopamine receptor activation can influence GABA neuron migration is not known. We show that dopamine D1 receptor activation promotes and D2 receptor activation decreases GABA neuron migration from the medial and caudal ganglionic eminences to the cerebral cortex in slice preparations of embryonic mouse forebrain. Slice preparations from D1 or D2 receptor knock-out mouse embryos confirm the findings. In addition, D1 receptor electroporation into cells of the basal forebrain and pharmacological activation of the receptor promote migration of the electroporated cells to the cerebral cortex. Analysis of GABA neuron numbers in the cerebral wall of the dopamine receptor knock-out mouse embryos further confirmed the effects of dopamine receptor activation on GABA neuron migration. Finally, dopamine receptor activation mobilizes striatal neuronal cytoskeleton in a manner consistent with the effects on neuronal migration. These data show that impairing the physiological balance between D1 and D2 receptors can alter GABA neuron migration from the basal forebrain to the cerebral cortex. The intimate relationship between dopamine and GABA neuron development revealed here may offer novel insights into developmental disorders such as schizophrenia, attention deficit or autism, and fetal cocaine exposure, all of which are associated with dopamine and GABA imbalance. PMID:17409246

  14. Chronic hyperammonemia alters the circadian rhythms of corticosteroid hormone levels and of motor activity in rats.

    Science.gov (United States)

    Ahabrach, Hanan; Piedrafita, Blanca; Ayad, Abdelmalik; El Mlili, Nisrin; Errami, Mohammed; Felipo, Vicente; Llansola, Marta

    2010-05-15

    Patients with liver cirrhosis may present hepatic encephalopathy with a wide range of neurological disturbances and alterations in sleep quality and in the sleep-wake circadian rhythm. Hyperammonemia is a main contributor to the neurological alterations in hepatic encephalopathy. We have assessed, in an animal model of chronic hyperammonemia without liver failure, the effects of hyperammonemia per se on the circadian rhythms of motor activity, temperature, and plasma levels of adrenal corticosteroid hormones. Chronic hyperammonemia alters the circadian rhythms of locomotor activity and of cortisol and corticosterone levels in blood. Different types of motor activity are affected differentially. Hyperammonemia significantly alters the rhythm of spontaneous ambulatory activity, reducing strongly ambulatory counts and slightly average velocity during the night (the active phase) but not during the day, resulting in altered circadian rhythms. In contrast, hyperammonemia did not affect wheel running at all, indicating that it affects spontaneous but not voluntary activity. Vertical activity was affected only very slightly, indicating that hyperammonemia does not induce anxiety. Hyperammonemia abolished completely the circadian rhythm of corticosteroid hormones in plasma, completely eliminating the peaks of cortisol and corticosterone present in control rats at the start of the dark period. The data reported show that chronic hyperammonemia, similar to that present in patients with liver cirrhosis, alters the circadian rhythms of corticosteroid hormones and of motor activity. This suggests that hyperammonemia would be a relevant contributor to the alterations in corticosteroid hormones and in circadian rhythms in patients with liver cirrhosis. PMID:19998493

  15. Radiation-induced alterations of histone post-translational modification levels in lymphoblastoid cell lines

    International Nuclear Information System (INIS)

    Radiation-induced alterations in posttranslational histone modifications (PTMs) may affect the cellular response to radiation damage in the DNA. If not reverted appropriately, altered PTM patterns may cause long-term alterations in gene expression regulation and thus lead to cancer. It is therefore important to characterize radiation-induced alterations in PTM patterns and the factors affecting them. A lymphoblastoid cell line established from a normal donor was used to screen for alterations in methylation levels at H3K4, H3K9, H3K27, and H4K20, as well as acetylation at H3K9, H3K56, H4K5, and H4K16, by quantitative Western Blot analysis at 15 min, 1 h and 24 h after irradiation with 2 Gy and 10 Gy. The variability of alterations in acetylation marks was in addition investigated in a panel of lymphoblastoid cell lines with differing radiosensitivity established from lung cancer patients. The screening procedure demonstrated consistent hypomethylation at H3K4me3 and hypoacetylation at all acetylation marks tested. In the panel of lymphoblastoid cell lines, however, a high degree of inter-individual variability became apparent. Radiosensitive cell lines showed more pronounced and longer lasting H4K16 hypoacetylation than radioresistant lines, which correlates with higher levels of residual γ-H2AX foci after 24 h. So far, the factors affecting extent and duration of radiation-induced histone alterations are poorly defined. The present work hints at a high degree of inter-individual variability and a potential correlation of DNA damage repair capacity and alterations in PTM levels

  16. GABA metabolism pathway genes, UGA1 and GAD1, regulate replicative lifespan in Saccharomycescerevisiae

    Energy Technology Data Exchange (ETDEWEB)

    Kamei, Yuka; Tamura, Takayuki [Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura, Nagahama, Shiga 526-0829 (Japan); Yoshida, Ryo [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Ohta, Shinji [Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura, Nagahama, Shiga 526-0829 (Japan); Fukusaki, Eiichiro [Department of Biotechnology, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871 (Japan); Mukai, Yukio, E-mail: y_mukai@nagahama-i-bio.ac.jp [Department of Bioscience, Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, 1266 Tamura, Nagahama, Shiga 526-0829 (Japan)

    2011-04-01

    Highlights: {yields}We demonstrate that two genes in the yeast GABA metabolism pathway affect aging. {yields} Deletion of the UGA1 or GAD1 genes extends replicative lifespan. {yields} Addition of GABA to wild-type cultures has no effect on lifespan. {yields} Intracellular GABA levels do not differ in longevity mutants and wild-type cells. {yields} Levels of tricarboxylic acid cycle intermediates positively correlate with lifespan. -- Abstract: Many of the genes involved in aging have been identified in organisms ranging from yeast to human. Our previous study showed that deletion of the UGA3 gene-which encodes a zinc-finger transcription factor necessary for {gamma}-aminobutyric acid (GABA)-dependent induction of the UGA1 (GABA aminotransferase), UGA2 (succinate semialdehyde dehydrogenase), and UGA4 (GABA permease) genes-extends replicative lifespan in the budding yeast Saccharomycescerevisiae. Here, we found that deletion of UGA1 lengthened the lifespan, as did deletion of UGA3; in contrast, strains with UGA2 or UGA4 deletions exhibited no lifespan extension. The {Delta}uga1 strain cannot deaminate GABA to succinate semialdehyde. Deletion of GAD1, which encodes the glutamate decarboxylase that converts glutamate into GABA, also increased lifespan. Therefore, two genes in the GABA metabolism pathway, UGA1 and GAD1, were identified as aging genes. Unexpectedly, intracellular GABA levels in mutant cells (except for {Delta}uga2 cells) did not differ from those in wild-type cells. Addition of GABA to culture media, which induces transcription of the UGA structural genes, had no effect on replicative lifespan of wild-type cells. Multivariate analysis of {sup 1}H nuclear magnetic resonance spectra for the whole-cell metabolite levels demonstrated a separation between long-lived and normal-lived strains. Gas chromatography-mass spectrometry analysis of identified metabolites showed that levels of tricarboxylic acid cycle intermediates positively correlated with lifespan

  17. GABA metabolism pathway genes, UGA1 and GAD1, regulate replicative lifespan in Saccharomycescerevisiae

    International Nuclear Information System (INIS)

    Highlights: →We demonstrate that two genes in the yeast GABA metabolism pathway affect aging. → Deletion of the UGA1 or GAD1 genes extends replicative lifespan. → Addition of GABA to wild-type cultures has no effect on lifespan. → Intracellular GABA levels do not differ in longevity mutants and wild-type cells. → Levels of tricarboxylic acid cycle intermediates positively correlate with lifespan. -- Abstract: Many of the genes involved in aging have been identified in organisms ranging from yeast to human. Our previous study showed that deletion of the UGA3 gene-which encodes a zinc-finger transcription factor necessary for γ-aminobutyric acid (GABA)-dependent induction of the UGA1 (GABA aminotransferase), UGA2 (succinate semialdehyde dehydrogenase), and UGA4 (GABA permease) genes-extends replicative lifespan in the budding yeast Saccharomycescerevisiae. Here, we found that deletion of UGA1 lengthened the lifespan, as did deletion of UGA3; in contrast, strains with UGA2 or UGA4 deletions exhibited no lifespan extension. The Δuga1 strain cannot deaminate GABA to succinate semialdehyde. Deletion of GAD1, which encodes the glutamate decarboxylase that converts glutamate into GABA, also increased lifespan. Therefore, two genes in the GABA metabolism pathway, UGA1 and GAD1, were identified as aging genes. Unexpectedly, intracellular GABA levels in mutant cells (except for Δuga2 cells) did not differ from those in wild-type cells. Addition of GABA to culture media, which induces transcription of the UGA structural genes, had no effect on replicative lifespan of wild-type cells. Multivariate analysis of 1H nuclear magnetic resonance spectra for the whole-cell metabolite levels demonstrated a separation between long-lived and normal-lived strains. Gas chromatography-mass spectrometry analysis of identified metabolites showed that levels of tricarboxylic acid cycle intermediates positively correlated with lifespan extension. These results strongly suggest

  18. Influence of GABA and GABA-producing Lactobacillus brevis DPC 6108 on the development of diabetes in a streptozotocin rat model.

    Science.gov (United States)

    Marques, T M; Patterson, E; Wall, R; O'Sullivan, O; Fitzgerald, G F; Cotter, P D; Dinan, T G; Cryan, J F; Ross, R P; Stanton, C

    2016-06-01

    The aim of this study was to investigate if dietary administration of γ-aminobutyric acid (GABA)-producing Lactobacillus brevis DPC 6108 and pure GABA exert protective effects against the development of diabetes in streptozotocin (STZ)-induced diabetic Sprague Dawley rats. In a first experiment, healthy rats were divided in 3 groups (n=10/group) receiving placebo, 2.6 mg/kg body weight (bw) pure GABA or L. brevis DPC 6108 (~10(9)microorganisms). In a second experiment, rats (n=15/group) were randomised to five groups and four of these received an injection of STZ to induce type 1 diabetes. Diabetic and non-diabetic controls received placebo [4% (w/v) yeast extract in dH2O], while the other three diabetic groups received one of the following dietary supplements: 2.6 mg/kg bw GABA (low GABA), 200 mg/kg bw GABA (high GABA) or ~10(9) L. brevis DPC 6108. L. brevis DPC 6108 supplementation was associated with increased serum insulin levels (Prats. Diabetes induced by STZ injection decreased body weight (Pglucose was increased (Pglucose levels was observed in diabetic rats receiving L. brevis DPC 6108, compared with diabetic-controls. Both the composition and diversity of the intestinal microbiota were affected by diabetes. Microbial diversity in diabetic rats supplemented with low GABA was not reduced (P>0.05), compared with non-diabetic controls while all other diabetic groups displayed reduced diversity (P<0.05). L. brevis DPC 6108 attenuated hyperglycaemia induced by diabetes but additional studies are needed to understand the mechanisms involved in this reduction. PMID:27013462

  19. Activity-mediated plasticity of GABA equilibrium potential in rat hippocampal CA1 neurons.

    Science.gov (United States)

    Yang, B; Tadavarty, R; Xu, J-Y; Sastry, B R

    2010-01-01

    The equilibrium potential (E(GABA)(-PSC)) for gamma-aminobutyric acid (GABA) A receptor mediated inhibitory postsynaptic currents (PSCs) in hippocampal CA1 pyramidal neurons shifts when theta-burst stimulation (four pulses at 100 Hz in each burst in a train consisting of five bursts with an inter-burst interval of 200 ms, the train repeated thrice at 30-s intervals) is applied to the input. E(GABA)(-PSC) is regulated by K(+)/Cl(-) co-transporter (KCC2). GABA(B) receptors are implicated in modulating KCC2 levels. In the current study, the involvement of KCC2, as well as GABA(B) receptors, in theta-burst-mediated shifts in E(GABA)(-PSC) was examined. Whole-cell patch recordings were made from hippocampal CA1 pyramidal neurons (from 9 to 12 days old rats), in a slice preparation. Glutamatergic excitatory postsynaptic currents were blocked with dl-2-amino-5-phosphonovaleric acid (50 microM) and 6,7-dinitroquinoxaline-2,3-dione (20 microM). The PSC and the E(GABA)(-PSC) were stable when stimulated at 0.05 Hz. However, both changed following a 30-min stimulation at 0.5 or 1 Hz. Furosemide (500 microM) and KCC2 anti-sense in the recording pipette but not bumetanide (20 or 100 microM) or KCC2 sense, blocked the changes, suggesting KCC2 involvement. Theta-burst stimulation induced a negative shift in E(GABA)(-PSC), which was prevented by KCC2 anti-sense; however, KCC2 sense had no effect. CGP55845 (2 microM), a GABA(B) antagonist, applied in the superfusing medium, or GDP-beta-S in the recording pipette, blocked the shift in E(GABA)(-PSC). These results indicate that activity-mediated plasticity in E(GABA)(-PSC) occurs in hippocampal CA1 pyramidal neurons and theta-burst-induced negative shift in E(GABA)(-PSC) requires KCC2, GABA(B) receptors and G-protein activation. PMID:19879261

  20. GABA in Paraventricular Nucleus Regulates Adipose Afferent Reflex in Rats.

    Directory of Open Access Journals (Sweden)

    Lei Ding

    Full Text Available Chemical stimulation of white adipose tissue (WAT induces adipose afferent reflex (AAR, and thereby causes a general sympathetic activation. Paraventricular nucleus (PVN is important in control of sympathetic outflow. This study was designed to investigate the role of γ-aminobutyric acid (GABA in PVN in regulating the AAR.Experiments were carried out in anesthetized rats. Renal sympathetic nerve activity (RSNA and mean arterial pressure (MAP were continuously recorded. AAR was evaluated by the RSNA and MAP responses to electrical stimulation of the right epididymal WAT (eWAT afferent nerve. Electrical stimulation of eWAT afferent nerve increase RSNA. Bilateral microinjection of the GABAA receptor agonist isoguvacine or the GABAB receptor agonist baclofen attenuated the AAR. The effect of isoguvacine on the AAR was greater than that of baclofen. The GABAA receptor antagonist gabazine enhanced the AAR, while the GABAB receptor antagonist CGP-35348 had no significant effect on the AAR. Bilateral PVN microinjection of vigabatrin, a selective GABA-transaminase inhibitor, to increase endogenous GABA levels in the PVN abolished the AAR. The inhibitory effect of vigabatrin on the AAR was attenuated by the pretreatment with gabazine or CGP-35348. Pretreatment with combined gabazine and CGP-35348 abolished the effects of vigabatrin.Activation of GABAA or GABAB receptors in the PVN inhibits the AAR. Blockade of GABAA receptors in the PVN enhances the AAR. Endogenous GABA in the PVN plays an important role in regulating the AAR.

  1. Ionotropic GABA Receptors and Distal Retinal ON and OFF Responses

    Directory of Open Access Journals (Sweden)

    E. Popova

    2014-01-01

    Full Text Available In the vertebrate retina, visual signals are segregated into parallel ON and OFF pathways, which provide information for light increments and decrements. The segregation is first evident at the level of the ON and OFF bipolar cells in distal retina. The activity of large populations of ON and OFF bipolar cells is reflected in the b- and d-waves of the diffuse electroretinogram (ERG. The role of gamma-aminobutyric acid (GABA, acting through ionotropic GABA receptors in shaping the ON and OFF responses in distal retina, is a matter of debate. This review summarized current knowledge about the types of the GABAergic neurons and ionotropic GABA receptors in the retina as well as the effects of GABA and specific GABAA and GABAC receptor antagonists on the activity of the ON and OFF bipolar cells in both nonmammalian and mammalian retina. Special emphasis is put on the effects on b- and d-waves of the ERG as a useful tool for assessment of the overall function of distal retinal ON and OFF channels. The role of GABAergic system in establishing the ON-OFF asymmetry concerning the time course and absolute and relative sensitivity of the ERG responses under different conditions of light adaptation in amphibian retina is also discussed.

  2. Selective GABA transporter inhibitors tiagabine and EF1502 exhibit mechanistic differences in their ability to modulate the ataxia and anticonvulsant action of the extrasynaptic GABA(A) receptor agonist gaboxadol

    DEFF Research Database (Denmark)

    Madsen, Karsten Kirkegaard; Ebert, Bjarke; Clausen, Rasmus Prætorius; Krogsgaard-Larsen, Povl; Schousboe, Arne; White, H Steve

    2011-01-01

    Modulation of the extracellular levels of GABA via inhibition of the synaptic GABA transporter GAT1 by the clinically effective and selective GAT1 inhibitor tiagabine [(R)-N-[4,4-bis(3-methyl-2-thienyl)-3-butenyl]nipecotic acid; Gabitril] has proven to be an effective treatment strategy for focal...

  3. GABA not only a neurotransmitter: osmotic regulation by GABAAR signalling

    Directory of Open Access Journals (Sweden)

    Tiziana Cesetti

    2012-01-01

    Full Text Available In neurons the anionic channel γ-aminobutyric (GABA A receptor (GABAAR plays a central role in mediating both the neurotrophic and neurotransmitter role of GABA. Activation of this receptor by GABA also affects the function of non-neuronal cells in the central nervous system (CNS, as GABAARs are expressed in mature macroglia and in almost all progenitor types, including neural stem cells. The relevance of GABA signalling in non-neuronal cells has been comparatively less investigated than in neurons. However, it is becoming increasingly evident that these cells are direct targets of GABA regulation. In non-neuronal cells GABAAR activation leads to influx or efflux of chloride (Cl- depending on the electrochemical gradient. Ion transport is indissolubly associated to water fluxes across the plasma membrane and plays a key role in brain physiology. Therefore, GABAAR could affect osmotic tension in the brain by modulating ion gradients. In addition, since water movements also occur through specialized water channels and transporters, GABAAR signalling could affect the movement of water also by regulating the function of the channels and transporters involved, thereby affecting not only the direction of the water fluxes but also their dynamics. This regulation has consequences at the cellular level as it modulates cell volume and activates multiple intracellular signalling mechanisms important for cell proliferation, maturation and survival. It may also have consequences at the systemic level. For example, it may indirectly control neuronal excitability, by regulating the extracellular space and interstitial concentration of Cl-, and contribute to brain water homeostasis. Therefore, GABAergic osmotic regulation should be taken into account during the treatment of pathologies requiring the administration of GABAAR modulators and for the development of therapies for diseases causing water unbalance in the brain.

  4. GAD67-mediated GABA Synthesis and Signaling Regulate Inhibitory Synaptic Innervation in the Visual Cortex

    Science.gov (United States)

    Chattopadhyaya, Bidisha; Di Cristo, Graziella; Wu, Cai Zhi; Knott, Graham; Kuhlman, Sandra; Fu, Yu; Palmiter, Richard D.; Huang, Z. Josh

    2007-01-01

    The development of GABAergic inhibitory circuits is shaped by neural activity, but the underlying mechanisms are unclear. we demonstrate a novel function of GABA in regulating GABAergic innervation in the adolescent brain, when GABA is mainly known as an inhibitory transmitter. Conditional knockdown of the rate-limiting synthetic enzyme GAD67 in basket interneurons in adolescent visual cortex resulted in cell autonomous deficits in axon branching, perisomatic synapse formation around pyramidal neurons, and complexity of the innervation fields; the same manipulation had little influence on the subsequent maintenance of perisomatic synapses. These effects of GABA deficiency were rescued by suppressing GABA re-uptake and by GABA receptor agonists. Germ-line knockdown of GAD67 but not GAD65 showed similar deficits, suggesting a specific role of GAD67 in the maturation of perisomatic innervation. Since intracellular GABA levels are modulated by neuronal activity, our results implicate GAD67-mediated GABA synthesis in activity-dependent regulation of inhibitory innervation patterns. PMID:17582330

  5. Closing the loop on the GABA shunt in plants: are GABA metabolism and signaling entwined?

    OpenAIRE

    Michaeli, Simon; Fromm, Hillel

    2015-01-01

    γ-Aminobutyric acid (GABA) is a non-proteinogenic amino acid that is found in uni- and multi-cellular organisms and is involved in many aspects of plant life cycle. GABA metabolism occurs by the action of evolutionary conserved enzymes that constitute the GABA shunt, bypassing two steps of the TCA cycle. The central position of GABA in the interface between plant carbon and nitrogen metabolism is well established. In parallel, there is evidence to support a role for GABA as a signaling molecu...

  6. Closing the Loop on the GABA Shunt in Plants: Are GABA metabolism and signaling entwined?

    OpenAIRE

    Simon eMichaeli; Hillel eFromm

    2015-01-01

    γ-Aminobutyric acid (GABA) is a non-proteinogenic amino acid that is found in uni- and multi-cellular organisms and is involved in many aspects of plant life cycle. GABA metabolism occurs by the action of evolutionary conserved enzymes that constitute the GABA shunt, bypassing two steps of the TCA cycle. The central position of GABA in the interface between plant carbon and nitrogen metabolism is well established. In parallel, there is evidence to support a role for GABA as a signaling molecu...

  7. Alternative complement pathway and factor B activities in rats with altered blood levels of thyroid hormone

    Energy Technology Data Exchange (ETDEWEB)

    Bitencourt, C.S. [Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil); Duarte, C.G.; Azzolini, A.E.C.S.; Assis-Pandochi, A.I. [Departamento de Física e Química, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP (Brazil)

    2012-03-02

    Evaluating the activity of the complement system under conditions of altered thyroid hormone levels might help elucidate the role of complement in triggering autoimmune processes. Here, we investigated alternative pathway (AP) activity in male Wistar rats (180 ± 10 g) after altering their thyroid hormone levels by treatment with triiodothyronine (T3), propylthiouracil (PTU) or thyroidectomy. T3 and thyroxine (T4) levels were determined by chemiluminescence assays. Hemolytic assays were performed to evaluate the lytic activity of the AP. Factor B activity was evaluated using factor B-deficient serum. An anti-human factor B antibody was used to measure factor B levels in serum by radial immunodiffusion. T3 measurements in thyroidectomized animals or animals treated with PTU demonstrated a significant reduction in hormone levels compared to control. The results showed a reduction in AP lytic activity in rats treated with increasing amounts of T3 (1, 10, or 50 µg). Factor B activity was also decreased in the sera of hyperthyroid rats treated with 1 to 50 µg T3. Additionally, treating rats with 25 µg T3 significantly increased factor B levels in their sera (P < 0.01). In contrast, increased factor B concentration and activity (32%) were observed in hypothyroid rats. We conclude that alterations in thyroid hormone levels affect the activity of the AP and factor B, which may in turn affect the roles of AP and factor B in antibody production.

  8. The effects of altered levels of UV-B radiation on an Antarctic grass and lichen

    NARCIS (Netherlands)

    Lud, D.; Huiskes, A.H.L.; Moerdijk-Poortvliet, T.C.W.; Rozema, J.J.

    2001-01-01

    We report a long-term experiment on the photosynthetic response of natural vegetation of Deschampsia antarctica (Poaceae) and Turgidosculum complicatulum (Lichenes) to altered UV-B levels on Leonie Island, Antarctica. UV-B above the vegetation was reduced by filter screens during two seasons. Half o

  9. Alterations in serum immunoglobulin levels in workers occupationally exposed to trichloroethylene

    OpenAIRE

    Zhang, Luoping; Bassig, Bryan A.; Mora, Joseph L.; Vermeulen, Roel; Ge, Yichen; Curry, John D.; Hu, Wei; Shen, Min; Qiu, Chuangyi; Ji, Zhiying; Reiss, Boris; McHale, Cliona M.; Liu, Songwang; Guo, Weihong; Purdue, Mark P.

    2012-01-01

    Trichloroethylene (TCE) has been associated with a variety of immunotoxic effects and may be associated with an increased risk of non-Hodgkin lymphoma (NHL). Altered serum immunoglobulin (Ig) levels have been reported in NHL patients and in animals exposed to TCE. Recently, we reported that occupational exposure to TCE is associated with immunosuppressive effects and immune dysfunction, including suppression of B-cell counts and activation, even at relatively low levels. We hypothesized that ...

  10. Alteration of Plasma Brain Natriuretic Peptide Level After Acute Moderate Exercise in Professional Athletes

    OpenAIRE

    Homa Sheikhani; Mohammad Ali Babaee Beygi; Farhad Daryanoosh; Bijan Jafari

    2011-01-01

    Background: Cardiac fatigue or myocardial damage following exercise until complete exhaustion can increase blood levels of brain natriuretic peptide (BNP) in athletes. Objectives: The aim of the present study was to investigate the effect of resistance and acute moderate aerobic exercise on alterations in BNP levels in professional athletes. Materials and Methods: Forty professional athletes who had at least 3 years of a championship background in track and field (aerobic group) or bo...

  11. GABA localization in the nematode Ascaris

    International Nuclear Information System (INIS)

    A histochemical approach was used to examine the distribution of GABA-associated neurons in the nematode Ascaris, an organism whose small number of morphologically simple neurons make it an excellent preparation for analyzing neuronal phenotypes. Two GABAergic markers were examined: GABA-like immunoreactivity (GLIR), a marker for endogenous stores of GABA; and [3H]-GABA uptake, a marker for GABA uptake sites. Strong GLIR was present in the cell bodies, neurites and commissures of dorsal and ventral inhibitory motorneurons present in this region. Strong GLIR was also present in the cell bodies and processes of the four RME neurons in the nerve ring and in several other ganglionic neurons. Staining was absent in excitatory motorneurons, in ventral cord interneurons and in muscle cells and hypodermis. GABA uptake sites were found in single neural processes in both the ventral and dorsal nerve cords. [3H]-GABA labeling was also observed in the other two RME cells and several other cephalic neurons. Four putative cholinergic excitatory motorneurons in the retrovesicular ganglion (RVG) were heavily labeled. Ventral and dorsal nerve cord inhibitory motorneurons did not take up [3H]-GABA. Labeling of the ventral cord excitatory motorneuron somata and cell bodies was at or slightly above background. Heavy labeling of muscle cells was also observed

  12. GABA localization in the nematode Ascaris

    Energy Technology Data Exchange (ETDEWEB)

    Guastella, J.

    1988-01-01

    A histochemical approach was used to examine the distribution of GABA-associated neurons in the nematode Ascaris, an organism whose small number of morphologically simple neurons make it an excellent preparation for analyzing neuronal phenotypes. Two GABAergic markers were examined: GABA-like immunoreactivity (GLIR), a marker for endogenous stores of GABA; and ({sup 3}H)-GABA uptake, a marker for GABA uptake sites. Strong GLIR was present in the cell bodies, neurites and commissures of dorsal and ventral inhibitory motorneurons present in this region. Strong GLIR was also present in the cell bodies and processes of the four RME neurons in the nerve ring and in several other ganglionic neurons. Staining was absent in excitatory motorneurons, in ventral cord interneurons and in muscle cells and hypodermis. GABA uptake sites were found in single neural processes in both the ventral and dorsal nerve cords. ({sup 3}H)-GABA labeling was also observed in the other two RME cells and several other cephalic neurons. Four putative cholinergic excitatory motorneurons in the retrovesicular ganglion (RVG) were heavily labeled. Ventral and dorsal nerve cord inhibitory motorneurons did not take up ({sup 3}H)-GABA. Labeling of the ventral cord excitatory motorneuron somata and cell bodies was at or slightly above background. Heavy labeling of muscle cells was also observed.

  13. Fatty acid ethanolamide levels are altered in borderline personality and complex posttraumatic stress disorders.

    Science.gov (United States)

    Schaefer, Carola; Enning, Frank; Mueller, Juliane K; Bumb, J Malte; Rohleder, Cathrin; Odorfer, Thorsten M; Klosterkötter, Joachim; Hellmich, Martin; Koethe, Dagmar; Schmahl, Christian; Bohus, Martin; Leweke, F Markus

    2014-08-01

    Borderline personality (BPD) and complex posttraumatic stress disorders (PTSD) are both powerfully associated with the experience of interpersonal violence during childhood and adolescence. The disorders frequently co-occur and often result in pervasive problems in, e.g., emotion regulation and altered pain perception, where the endocannabinoid system is deeply involved. We hypothesize an endocannabinoid role in both disorders. We investigated serum levels of the endocannabinoids anandamide and 2-arachidonoylglycerol and related fatty acid ethanolamides (FAEs) in BPD, PTSD, and controls. Significant alterations were found for both endocannabinoids in BPD and for the FAE oleoylethanolamide in PTSD suggesting a respective link to both disorders. PMID:24253425

  14. Effects of Alterations of Plasma Free Fatty Acid Levels on Pancreatic Glucagon Secretion in Man

    Science.gov (United States)

    Gerich, John E.; Langlois, Maurice; Schneider, Victor; Karam, John H.; Noacco, Claudio

    1974-01-01

    The present investigation was undertaken to ascertain whether alterations in plasma free fatty acids (FFA) affect pancreatic glucagon secretion in man since FFA have been reported to influence pancreatic alpha cell function in other species. Elevation of plasma FFA from a mean (±SE) basal level of 0.478±0.036 mM to 0.712±0.055 mM after heparin administration caused plasma glucagon levels to fall approximately 50%, from a basal value of 122±15 pg/ml to 59±14 pg/ml (P < 0.001). Lowering of plasma FFA from a basal level of 0.520±0.046 mM to 0.252±0.041 mM after nicotinic acid administration raised plasma glucagon from a basal level of 113±18 pg/ml to 168±12 pg/ml (P < 0.005). Infusion of glucose elevated plasma glucose levels to the same degree that heparin raised plasma FFA levels. This resulted in suppression of plasma glucagon despite the fact that plasma FFA levels also were suppressed. Glucagon responses to arginine were diminished after elevation of plasma FFA (P < 0.01) and during infusion of glucose (P < 0.01). Diminution of plasma FFA by nicotinic acid did not augment glucagon responses to arginine. These results thus demonstrate that rather small alterations in plasma FFA within the physiologic range have a significant effect on glucagon secretion in man. Although the effects of glucose appear to predominate over those of FFA, alterations in plasma FFA may nevertheless exert an important physiologic influence over human pancreatic alpha cell function, especially in the postabsorptive state. PMID:4825225

  15. Mutations in the GABA Transporter SLC6A1 Cause Epilepsy with Myoclonic-Atonic Seizures

    DEFF Research Database (Denmark)

    Carvill, Gemma L; McMahon, Jacinta M; Schneider, Amy;

    2015-01-01

    in seven individuals, all of whom have epilepsy with myoclonic-atonic seizures (MAE). We describe two truncations and four missense alterations, all of which most likely lead to loss of function of GAT-1 and thus reduced GABA re-uptake from the synapse. These individuals share many of the...

  16. The Volitional Nature of Nicotine Exposure Alters Anandamide and Oleoylethanolamide Levels in the Ventral Tegmental Area

    OpenAIRE

    Buczynski, Matthew W.; Polis, Ilham Y; Parsons, Loren H.

    2012-01-01

    Cannabinoid-1 receptors (CB1) have an important role in nicotine reward and their function is disrupted by chronic nicotine exposure, suggesting nicotine-induced alterations in endocannabinoid (eCB) signaling. However, the effects of nicotine on brain eCB levels have not been rigorously evaluated. Volitional intake of nicotine produces physiological and behavioral effects distinct from forced drug administration, although the mechanisms underlying these effects are not known. This study compa...

  17. stem fasciated, a Recessive Mutation in Sunflower (Helianthus annuus), Alters Plant Morphology and Auxin Level

    OpenAIRE

    FAMBRINI, MARCO; BONSIGNORI, ELISA; RAPPARINI, FRANCESCA; CIONINI, GIULIANO; Michelotti, Vania; BERTINI, DANIELE; BARALDI, RITA; PUGLIESI, CLAUDIO

    2006-01-01

    • Background and Aims Plant lateral organs such as leaves arise from a group of initial cells within the flanks of the shoot apical meristem (SAM). Alterations in the initiation of lateral organs are often associated with changes in the dimension and arrangement of the SAM as well as with abnormal hormonal homeostasis. A mutation named stem fasciated (stf) that affects various aspects of plant development, including SAM shape and auxin level, was characterized in sunflower (Helianthus annuus).

  18. GABA(A) receptor- and GABA transporter polymorphisms and risk for essential tremor

    DEFF Research Database (Denmark)

    Thier, S; Kuhlenbäumer, G; Lorenz, D;

    2011-01-01

    Background:  Clinical features and animal models of essential tremor (ET) suggest gamma-aminobutyric acid A receptor (GABA(A) R) subunits and GABA transporters as putative candidate genes. Methods:  A total of 503 ET cases and 818 controls were investigated for an association between polymorphisms...... in 15 GABA(A) R and four GABA transporter genes and ET. Results:  Nine nominally significant tagging SNPs (P values from 4.9 × 10(-2) to 5.2 × 10(-4) ) were found in the hypothesis generation stage. Five SNPs were followed up in a second verification stage but failed to reach significance. (P values...... from 0.30 to 0.77). Discussion:  In our samples, no evidence of association between GABA(A) R and GABA transporter genes with ET was detected. Further studies are necessary to clarify the role of these genes in ET....

  19. GABA and Topiramate Inhibit the Formation of Human Macrophage-Derived Foam Cells by Modulating Cholesterol-Metabolism-Associated Molecules

    Directory of Open Access Journals (Sweden)

    Ying Yang

    2014-04-01

    Full Text Available Aims: γ-aminobutyric acid (GABA, the principal inhibitory neurotransmitter, acts on GABA receptors to play an important role in the modulation of macrophage functions. The present study examined the effects of GABA and a GABA receptor agonist on modulating cholesterol-metabolism-associated molecules in human monocyte-derived macrophages (HMDMs. Methods: ORO stain, HPLC, qRT-PCR, Western blot and EMSA were carried out using HMDMs exposed to ox-LDL with or without GABAergic agents as the experimental model. Results: GABA and topiramate reduced the percentage of cholesterol ester in lipid-laden HMDMs by down-regulating SR-A, CD36 and LOX-1 expression and up-regulating ABCA1, ABCG1 and SR-BI expression in lipid-laden HMDMs. The production of TNF-a was decreased in GABA-and topiramate-treated lipid-laden HMDMs, and levels of interleukin (IL-6 did not change. The activation of two signaling pathways, p38MAPK and NF-γB, was repressed by GABA and topiramate in lipid-laden HMDMs. Conclusion: GABA and topiramate inhibit the formation of human macrophage-derived foam cells and may be a possibility for macrophage targeted therapy of atherosclerotic lesions.

  20. Age-Related Loss of GABA-Positive and GABA-Negative Neurons in Neocortical Transplants

    OpenAIRE

    Bragin, A.; Takács, J.; Vinogradova, O.; Gogelia, Kh.; Hámori, J

    1993-01-01

    The numerical density of GABA immunopositive and GABA immunonegative neurons was quantitatively determined in 0, 12, 30 and 90 day-old neocortical transplants, derived from E17 rat embryos and transplanted into adult hosts. It was found that the original, very high neuronal density in the fetal transplant declined steadily after transplantation to the somatosensory cortex of adult rat. The decline in numerical density of GABA-positive neurons, however, was disproportionately larger than that ...

  1. Action of bicyclic isoxazole GABA analogues on GABA transporters and its relation to anticonvulsant activity

    DEFF Research Database (Denmark)

    Bolvig, T; Larsson, O M; Pickering, D S;

    1999-01-01

    The inhibitory action of bicyclic isoxazole gamma-aminobutyric acid (GABA) analogues and their 4,4-diphenyl-3-butenyl (DPB) substituted derivatives has been investigated in cortical neurones and astrocytes as well as in human embryonic kidney (HEK 293) cells transiently expressing either mouse GABA...... anticonvulsant activity, lack of proconvulsant activity and the ability of THPO to increase extracellular GABA concentration, indicate that these bicyclic isoxazole GABA analogues and their DPB derivatives may be useful lead structures in future search for new antiepileptic drugs....

  2. GABA-noradrenergic interaction: evidence for differential sites of action for GABA-A and GABA-B receptors

    International Nuclear Information System (INIS)

    Treatment of mice with DSP4 (a neurotoxin that abolishes the presynaptic noradrenergic neuron; Dooley et al., 1983) resulted in: (A) a decrease in the Bsub(max) for the low affinity GABA-B receptor site in the cerebal cortex and hippocampus, whereas the Bsub(max) for the high affinity GABA-B receptor site was unaffected; (B) a greater potentiation of norepinephrine stimulated adenylate cyclase by baclofen in cerebal cortex slices; and (C) a decrease in the Bsub(max) for both the high and low affinity GABA-A receptor sites in the cerebal cortex and hippocampus. These data, coupled with previous work from our laboratory, suggest that the GABA-B receptor may be associated with both the noradrenergic nerve terminal and the post-synaptic neuron receiving noradrenergic input, whereas the GABA-B receptor may be associated with the noradrenergic nerve terminal. These data further suggest a functional coupling between the noradrenergic and GABA-ergic systems. (Author)

  3. The role of GABA in the hypoxia tolerance of the epaulette shark

    International Nuclear Information System (INIS)

    Full text: The epaulette shark responds to hypoxia with brain hypometabolism which is correlated with increased levels of gamma-aminobutyric acid (GABA). We examined GABA-like immunoreactivity (GABA-IR) and the density and binding characteristics of GABA A receptors in the Epaulette shark brainstem. These studies were conducted to investigate changes in response to hypoxia. Experimental animals were exposed to eight cycles of an extreme hypoxic regimen (5% of normoxia). Animals were anaesthetised with 80mg/L of MS222 and the brain was dissected and processed either for immunohistochemistry or receptor ligand binding. Membranes were prepared at 4 deg C according to a previously reported protocol and the binding characteristics of [3H]flunitrazeparn ([3H]FNZ) were examined using an in vitro centrifugation assay. We report on the effect of hypoxia on specific [3H]FNZ binding characteristics. GABA-IR was detected using a primary antibody dilution of 1:15 000 and the Vector ABC method. We report that an overall increase in the optical density of GABA-IR occurs with significant increases in three out of the four brainstem nuclei examined in experimental animals. The results of these studies are discussed in conjunction with the hypoxia-tolerance .of the epaulette shark. Copyright (1998) Australian Neuroscience Society

  4. Effects of traditionally used anxiolytic botanicals on enzymes of the gamma-aminobutyric acid (GABA) system.

    Science.gov (United States)

    Awad, R; Levac, D; Cybulska, P; Merali, Z; Trudeau, V L; Arnason, J T

    2007-09-01

    In Canada, the use of botanical natural health products (NHPs) for anxiety disorders is on the rise, and a critical evaluation of their safety and efficacy is required. The purpose of this study was to determine whether commercially available botanicals directly affect the primary brain enzymes responsible for gamma-aminobutyric acid (GABA) metabolism. Anxiolytic plants may interact with either glutamic acid decarboxylase (GAD) or GABA transaminase (GABA-T) and ultimately influence brain GABA levels and neurotransmission. Two in vitro rat brain homogenate assays were developed to determine the inhibitory concentrations (IC50) of aqueous and ethanolic plant extracts. Approximately 70% of all extracts that were tested showed little or no inhibitory effect (IC50 values greater than 1 mg/mL) and are therefore unlikely to affect GABA metabolism as tested. The aqueous extract of Melissa officinalis (lemon balm) exhibited the greatest inhibition of GABA-T activity (IC50 = 0.35 mg/mL). Extracts from Centella asiatica (gotu kola) and Valeriana officinalis (valerian) stimulated GAD activity by over 40% at a dose of 1 mg/mL. On the other hand, both Matricaria recutita (German chamomile) and Humulus lupulus (hops) showed significant inhibition of GAD activity (0.11-0.65 mg/mL). Several of these species may therefore warrant further pharmacological investigation. The relation between enzyme activity and possible in vivo mode of action is discussed. PMID:18066140

  5. GABA and glycine in the developing brain.

    Science.gov (United States)

    Ito, Susumu

    2016-09-01

    GABA and glycine are major inhibitory neurotransmitters in the CNS and act on receptors coupled to chloride channels. During early developmental periods, both GABA and glycine depolarize membrane potentials due to the relatively high intracellular Cl(-) concentration. Therefore, they can act as excitatory neurotransmitters. GABA and glycine are involved in spontaneous neural network activities in the immature CNS such as giant depolarizing potentials (GDPs) in neonatal hippocampal neurons, which are generated by the synchronous activity of GABAergic interneurons and glutamatergic principal neurons. GDPs and GDP-like activities in the developing brains are thought to be important for the activity-dependent functiogenesis through Ca(2+) influx and/or other intracellular signaling pathways activated by depolarization or stimulation of metabotropic receptors. However, if GABA and glycine do not shift from excitatory to inhibitory neurotransmitters at the birth and in maturation, it may result in neural disorders including autism spectrum disorders. PMID:26951057

  6. A network of autism linked genes stabilizes two pools of synaptic GABA(A) receptors.

    Science.gov (United States)

    Tong, Xia-Jing; Hu, Zhitao; Liu, Yu; Anderson, Dorian; Kaplan, Joshua M

    2015-01-01

    Changing receptor abundance at synapses is an important mechanism for regulating synaptic strength. Synapses contain two pools of receptors, immobilized and diffusing receptors, both of which are confined to post-synaptic elements. Here we show that immobile and diffusing GABA(A) receptors are stabilized by distinct synaptic scaffolds at C. elegans neuromuscular junctions. Immobilized GABA(A) receptors are stabilized by binding to FRM-3/EPB4.1 and LIN-2A/CASK. Diffusing GABA(A) receptors are stabilized by the synaptic adhesion molecules Neurexin and Neuroligin. Inhibitory post-synaptic currents are eliminated in double mutants lacking both scaffolds. Neurexin, Neuroligin, and CASK mutations are all linked to Autism Spectrum Disorders (ASD). Our results suggest that these mutations may directly alter inhibitory transmission, which could contribute to the developmental and cognitive deficits observed in ASD. PMID:26575289

  7. Female Mice are Resistant to Fabp1 Gene Ablation-Induced Alterations in Brain Endocannabinoid Levels.

    Science.gov (United States)

    Martin, Gregory G; Chung, Sarah; Landrock, Danilo; Landrock, Kerstin K; Dangott, Lawrence J; Peng, Xiaoxue; Kaczocha, Martin; Murphy, Eric J; Kier, Ann B; Schroeder, Friedhelm

    2016-09-01

    Although liver fatty acid binding protein (FABP1, L-FABP) is not detectable in the brain, Fabp1 gene ablation (LKO) markedly increases endocannabinoids (EC) in brains of male mice. Since the brain EC system of females differs significantly from that of males, it was important to determine if LKO differently impacted the brain EC system. LKO did not alter brain levels of arachidonic acid (ARA)-containing EC, i.e. arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG), but decreased non-ARA-containing N-acylethanolamides (OEA, PEA) and 2-oleoylglycerol (2-OG) that potentiate the actions of AEA and 2-AG. These changes in brain potentiating EC levels were not associated with: (1) a net decrease in levels of brain membrane proteins associated with fatty acid uptake and EC synthesis; (2) a net increase in brain protein levels of cytosolic EC chaperones and enzymes in EC degradation; or (3) increased brain protein levels of EC receptors (CB1, TRVP1). Instead, the reduced or opposite responsiveness of female brain EC levels to loss of FABP1 (LKO) correlated with intrinsically lower FABP1 level in livers of WT females than males. These data show that female mouse brain endocannabinoid levels were unchanged (AEA, 2-AG) or decreased (OEA, PEA, 2-OG) by complete loss of FABP1 (LKO). PMID:27450559

  8. Altered Alpha-Synuclein, Parkin, and Synphilin Isoform Levels in Multiple System Atrophy Brains

    DEFF Research Database (Denmark)

    Brudek, Tomasz; Winge, Kristian; Bredo Rasmussen, Nadja;

    2016-01-01

    -1 isoforms. In MSA brains, alpha-synuclein140 and alpha-synuclein112 isoform levels were significantly increased,whereas levels of the alpha-synuclein126 isoform were decreased in the substantia nigra, striatum, cerebellar cortex, and nucleus dentatus vs. CONTROLS: Moreover, in MSA cases, we showed...... increased levels of parkin isoforms lacking the N-terminal ubiquitin-like domain and an aggregation-prone synphiln-1A isoform that causes neuronal toxicity in MSA. In PD brains, Parkin transcript variant 3, 7 and 11 were significantly and specifically overexpressed in the striatum and cerebellar cortex......, together with synphilin-1A and 1C. The changes of isoform expression profiles in neurodegenerative diseases suggest alterations in the regulation of transcription and/or splicing events, leading to regional/cellular events that may be important for the highly increased aggregation of alpha-synuclein in the...

  9. Modulation of ROS levels in fibroblasts by altering mitochondria regulates the process of wound healing.

    Science.gov (United States)

    Janda, Jaroslav; Nfonsam, Valentine; Calienes, Fernanda; Sligh, James E; Jandova, Jana

    2016-05-01

    Mitochondria are the major source of reactive oxygen species (ROS) in fibroblasts which are thought to be crucial regulators of wound healing with a potential to affect the expression of nuclear genes involved in this process. ROS generated by mitochondria are involved in all stages of tissue repair process but the regulation of ROS-generating system in fibroblasts still remains poorly understood. The purpose of this study was to better understand molecular mechanisms of how the regulation of ROS levels generated by mitochondria may influence the process of wound repair. Cybrid model system of mtDNA variations was used to study the functional consequences of altered ROS levels on wound healing responses in a uniform nuclear background of cultured ρ(0) fibroblasts. Mitochondrial ROS in cybrids were modulated by antioxidants that quench ROS to examine their ability to close the wound. Real-time PCR arrays were used to investigate whether ROS generated by specific mtDNA variants have the ability to alter expression of some key nuclear-encoded genes central to the wound healing response and oxidative stress. Our data suggest levels of mitochondrial ROS affect expression of some nuclear encoded genes central to wound healing response and oxidative stress and modulation of mitochondrial ROS by antioxidants positively affects in vitro process of wound closure. Thus, regulation of mitochondrial ROS-generating system in fibroblasts can be used as effective natural redox-based strategy to help treat non-healing wounds. PMID:26873374

  10. Accumulation of gamma-aminobutyrate (GABA) caused by heat-drying and expression of related genes in immature vegetable soybean (edamame)

    OpenAIRE

    TAKAHASHI, Yukiko; Sasanuma, Tsuneo; Abe, Toshinori

    2013-01-01

    We studied the effects of drying of immature seeds of vegetable soybean (Glycine max L. Merrill) on the accumulation of gamma-aminobutyrate (GABA) in the seeds. GABA accumulated after heat-drying, with the maximum at 40°C. The GABA content (447.5 mg/100 g DW) increased to more than 5 times the value in untreated seeds (79.6 mg/100 g DW). In contrast, the glutamate content decreased rapidly to 1/3 the level in the untreated seeds. The GABA content increased early in the heat-drying treatment: ...

  11. Effect of THIP and SL 76002, two clinically experimented GABA-mimetic compounds, on anterior pituitary GABA receptors and prolactin secretion in the rat

    International Nuclear Information System (INIS)

    In the present study, the ability of three direct GABA agonists, muscimol, THIP and SL 76002 to displace 3H-GABA binding from anterior pituitary and medio-basal hypothalamus membranes was evaluated. Further, the effect of both THIP and SL 76002 on baseline prolactin levels or after stimulation of hormone release with haloperidol has been also studied. Either muscimol, THIP or SL 76002 have shown to posses 7-, 7- and 3-fold higher affinity, respectively, for the central nervous system than for the anterior pituitary 3H-GABA binding sites. Moreover, THIP and SL 76002 have demonstrated to be respectively, 25- and 1000- fold less potent than muscimol in inhibiting 3H- GABA binding at the level of the anterior pituitary and about 25- and 2700-fold less potent at the level of the medio-basal hypothalamus. Under basal conditions, either THIP or SL 76002 were ineffective to reduce prolactin release. However, after stimulation of prolactin secretion through blockade of the dopaminergic neurotransmission with haloperidol (0.1 mg/kg), both THIP (10 mg/kg) and SL 76002 (200 mg/kg) significantly counteracted the neuroleptic-induced prolactin rise with a potency which is in line with their ability to inhibit 3H-GABA binding in the anterior pituitary. The present results indicate that both compounds inhibit prolactin release under specific experimental situations probably through a GABAergic mechanism. In view of the endocrine effects of these GABA-mimetic compounds, the possibility arises for an application of these type of drugs in clinical neuroendocrinology. 35 references, 3 figures, 2 tables

  12. Peripheral Levels of AGEs and Astrocyte Alterations in the Hippocampus of STZ-Diabetic Rats.

    Science.gov (United States)

    Nardin, Patrícia; Zanotto, Caroline; Hansen, Fernanda; Batassini, Cristiane; Gasparin, Manuela Sangalli; Sesterheim, Patrícia; Gonçalves, Carlos-Alberto

    2016-08-01

    Diabetic patients and streptozotocin (STZ)-induced diabetes mellitus (DM) models exhibit signals of brain dysfunction, evidenced by neuronal damage and memory impairment. Astrocytes surrounding capillaries and synapses modulate many brain activities that are connected to neuronal function, such as nutrient flux and glutamatergic neurotransmission. As such, cognitive changes observed in diabetic patients and experimental models could be related to astroglial alterations. Herein, we investigate specific astrocyte changes in the rat hippocampus in a model of DM induced by STZ, particularly looking at glial fibrillary acidic protein (GFAP), S100B protein and glutamate uptake, as well as the content of advanced glycated end products (AGEs) in serum and cerebrospinal fluid (CSF), as a consequence of elevated hyperglycemia and the content of receptor for AGEs in the hippocampus. We found clear peripheral alterations, including hyperglycemia, low levels of proinsulin C-peptide, elevated levels of AGEs in serum and CSF, as well as an increase in RAGE in hippocampal tissue. We found specific astroglial abnormalities in this brain region, such as reduced S100B content, reduced glutamate uptake and increased S100B secretion, which were not accompanied by changes in GFAP. We also observed an increase in the glucose transporter, GLUT-1. All these changes may result from RAGE-induced inflammation; these astroglial alterations together with the reduced content of GluN1, a subunit of the NMDA receptor, in the hippocampus may be associated with the impairment of glutamatergic communication in diabetic rats. These findings contribute to understanding the cognitive deficits in diabetic patients and experimental models. PMID:27084774

  13. Mineral abundances and different levels of alteration around Mawrth Vallis, Mars

    Institute of Scientific and Technical Information of China (English)

    Sheng Gou; Zongyu Yue; Kaichang Di; Jinnian Wang

    2015-01-01

    Spectral indices from OMEGA hyperspectral data show that there are two main phyllosilicates exposed in and around Mawrth Vallis: Al phyllosilicates and Fe/Mg phyllosilicates. Detailed analysis of CRISM spectra shows that Al phyllosilicates such as montmorillonite, hydrated silica, kaolinite; Fe/Mg phyllo-silicates such as nontronite, saponite, serpentine are widespread on the light-toned outcrops. Though similar stratigraphical sequences, morphologies and textures are observed on both sides of Mawrth Vallis from HiRISE images, suggesting that the geological processes that formed these units must have operated at a regional scale; the multiple endmember spectral mixture analysis (MESMA) derived mineral abundance indicates that there is a higher level of alteration in the western side relative to the eastern side. We suggest that the observed phyllosilicates, stratigraphical sequences and different levels of alteration might have been caused by sedimentary deposition processes in which the composition of the external source sediment or the local solution was different, or by a pedogenic process closely related to the leaching of abundant liquid water with different chemical properties.

  14. Diethylstilbestrol alters the morphology and calcium levels of growth cones of PC12 cells in vitro.

    Science.gov (United States)

    Janevski, J; Choh, V; Stopper, H; Schiffmann, D; De Boni, U

    1993-01-01

    Diethylstilbestrol (DES) is a synthetic estrogen with carcinogenic properties. DES is known to alter cytoskeletal components, including the organization of actin stress fibres in C6 rat glioma cells. In a test of the hypothesis that DES disrupts actin filaments of growth cones in neuron-like cells, DES-induced changes in filopodial lengths were quantified in rat pheochromocytoma (PC12) cells in vitro. DES significantly altered growth cone morphology, with collapse of growth cone filopodia and neurite retraction invariably occurring at a concentration of 10 microM. At 5 microM DES, transient reductions in total filopodial lengths occurred. At DES concentrations of 0.1 nM and 1 nM, reductions in total filopodial lengths occurred in a fraction of growth cones. Evidence exists which shows that growth cone activity and morphology are intimately linked to levels of intracellular, free calcium and that DES increases such levels. Measurements of free intracellular calcium levels by fluorescence microscopy, at times concurrent with the DES-induced reduction in total filopodial lengths, showed that calcium levels were indeed significantly increased by 10 microM DES. Labelling of filamentous actin (f-actin) with FITC-phalloidin showed that the f-actin distribution in growth cones exposed to DES could not be differentiated from the distribution found in spontaneously retracting growth cones. Together with evidence which showed that growth cone motility was not affected, the results are taken to indicate that DES, rather than acting directly on the cytoskeleton, exerts its effects indirectly, by a calcium-induced destabilization of actin filaments in the growth cone. PMID:8164893

  15. Audiovisual associations alter the perception of low-level visual motion

    Directory of Open Access Journals (Sweden)

    Hulusi Kafaligonul

    2015-03-01

    Full Text Available Motion perception is a pervasive nature of vision and is affected by both immediate pattern of sensory inputs and prior experiences acquired through associations. Recently, several studies reported that an association can be established quickly between directions of visual motion and static sounds of distinct frequencies. After the association is formed, sounds are able to change the perceived direction of visual motion. To determine whether such rapidly acquired audiovisual associations and their subsequent influences on visual motion perception are dependent on the involvement of higher-order attentive tracking mechanisms, we designed psychophysical experiments using regular and reverse-phi random dot motions isolating low-level pre-attentive motion processing. Our results show that an association between the directions of low-level visual motion and static sounds can be formed and this audiovisual association alters the subsequent perception of low-level visual motion. These findings support the view that audiovisual associations are not restricted to high-level attention based motion system and early-level visual motion processing has some potential role.

  16. Detection of Reduced GABA Synthesis Following Inhibition of GABA Transaminase Using in Vivo Magnetic Resonance Signal of [13C]GABA C1

    OpenAIRE

    Yang, Jehoon; Johnson, Christopher; Shen, Jun

    2009-01-01

    Previous in vivo magnetic resonance spectroscopy (MRS) studies of gamma-aminobutyric acid (GABA) synthesis have relied on 13C label incorporation into GABA C2 from [1-13C] or [1,6-13C2]glucose. In this study, the [13C]GABA C1 signal at 182.3 ppm in the carboxylic/amide spectral region of localized in vivo 13C spectra was detected. GABA-transaminase of rat brain was inhibited by administration of gabaculine after pre-labeling of GABA C1 and its metabolic precursors with exogenous [2,5-13C2]glu...

  17. Altered Levels of Serum Zinc and Cadmium in Patients with Chronic Vesiculobullous Hand and Feet Dermatitis

    Science.gov (United States)

    Suvirya, Swastika; Thakur, Alpna; Pandey, S. S.; Tripathi, S. K.; Dwivedi, Durgesh Kumar

    2016-01-01

    Micronutrients serve many important functions in our body and altered levels of heavy and trace metals are associated with cutaneous and systemic disorders. Vesicular palmoplantar eczema is an entity whose etiopathogenesis is a mystery. In this prospective case-noncase study blood levels of Zinc and Cadmium in 37 patients of chronic vesiculobullous hand dermatitis were estimated and compared with 40 noncases with similar age and gender distributions. Low serum Zinc levels were found in patients as compared to noncases. The mean difference of serum Zinc between the case and noncase groups was 27.26; the mean value of serum Zinc between the two groups was statistically significant (p < 0.0001). However, elevated Cadmium levels were detected in only 5 patients and in none of the noncases. The mean concentration of serum Cadmium was 2.32 ± 0.38 μg/dL, with a range of 1.90–2.80 μg/dL for the five cases in whom Cadmium was detected. Various toxic and trace metals can interact by influencing each other's absorption, retention, distribution, and bioavailability in the body. The clinical significance of this finding lies in the possible beneficial role of Zinc supplementation in the therapy of chronic vesiculobullous hand dermatitis.

  18. Electrical stimulation of the substantia nigra reticulata : Detection of neuronal extracellular GABA in the ventromedial thalamus and its regulatory mechanism using microdialysis in awake rats

    NARCIS (Netherlands)

    Timmerman, W; Westerink, BHC

    1997-01-01

    A combination of electrical stimulation and microdialysis was used to study the nigrothalamic gamma aminobutyric acid (GABA)ergic system and its regulatory mechanisms in awake rats. Extracellular GABA levels in the ventromedial nucleus of the thalamus were detected in S-min fractions collected befor

  19. VTA GABA neurons modulate specific learning behaviours through the control of dopamine and cholinergic systems

    Directory of Open Access Journals (Sweden)

    Meaghan C Creed

    2014-01-01

    Full Text Available The mesolimbic reward system is primarily comprised of the ventral tegmental area (VTA and the nucleus accumbens (NAc as well as their afferent and efferent connections. This circuitry is essential for learning about stimuli associated with motivationally-relevant outcomes. Moreover, addictive drugs affect and remodel this system, which may underlie their addictive properties. In addition to DA neurons, the VTA also contains approximately 30% ɣ-aminobutyric acid (GABA neurons. The task of signalling both rewarding and aversive events from the VTA to the NAc has mostly been ascribed to DA neurons and the role of GABA neurons has been largely neglected until recently. GABA neurons provide local inhibition of DA neurons and also long-range inhibition of projection regions, including the NAc. Here we review studies using a combination of in vivo and ex vivo electrophysiology, pharmacogenetic and optogenetic manipulations that have characterized the functional neuroanatomy of inhibitory circuits in the mesolimbic system, and describe how GABA neurons of the VTA regulate reward and aversion-related learning. We also discuss pharmacogenetic manipulation of this system with benzodiazepines (BDZs, a class of addictive drugs, which act directly on GABAA receptors located on GABA neurons of the VTA. The results gathered with each of these approaches suggest that VTA GABA neurons bi-directionally modulate activity of local DA neurons, underlying reward or aversion at the behavioural level. Conversely, long-range GABA projections from the VTA to the NAc selectively target cholinergic interneurons (CINs to pause their firing and temporarily reduce cholinergic tone in the NAc, which modulates associative learning. Further characterization of inhibitory circuit function within and beyond the VTA is needed in order to fully understand the function of the mesolimbic system under normal and pathological conditions.

  20. Comparative mapping of GABA-immunoreactive neurons in the central nervous systems of nudibranch molluscs.

    Science.gov (United States)

    Gunaratne, Charuni A; Sakurai, Akira; Katz, Paul S

    2014-03-01

    The relative simplicity of certain invertebrate nervous systems, such as those of gastropod molluscs, allows behaviors to be dissected at the level of small neural circuits composed of individually identifiable neurons. Elucidating the neurotransmitter phenotype of neurons in neural circuits is important for understanding how those neural circuits function. In this study, we examined the distribution of γ-aminobutyric-acid;-immunoreactive (GABA-ir) neurons in four species of sea slugs (Mollusca, Gastropoda, Opisthobranchia, Nudibranchia): Tritonia diomedea, Melibe leonina, Dendronotus iris, and Hermissenda crassicornis. We found consistent patterns of GABA immunoreactivity in the pedal and cerebral-pleural ganglia across species. In particular, there were bilateral clusters in the lateral and medial regions of the dorsal surface of the cerebral ganglia as well as a cluster on the ventral surface of the pedal ganglia. There were also individual GABA-ir neurons that were recognizable across species. The invariant presence of these individual neurons and clusters suggests that they are homologous, although there were interspecies differences in the numbers of neurons in the clusters. The GABAergic system was largely restricted to the central nervous system, with the majority of axons confined to ganglionic connectives and commissures, suggesting a central, integrative role for GABA. GABA was a candidate inhibitory neurotransmitter for neurons in central pattern generator (CPG) circuits underlying swimming behaviors in these species, however none of the known swim CPG neurons were GABA-ir. Although the functions of these GABA-ir neurons are not known, it is clear that their presence has been strongly conserved across nudibranchs. PMID:24638845

  1. Alteration of Plasma Brain Natriuretic Peptide Level After Acute Moderate Exercise in Professional Athletes

    Directory of Open Access Journals (Sweden)

    Homa Sheikhani

    2011-12-01

    Full Text Available Background: Cardiac fatigue or myocardial damage following exercise until complete exhaustion can increase blood levels of brain natriuretic peptide (BNP in athletes. Objectives: The aim of the present study was to investigate the effect of resistance and acute moderate aerobic exercise on alterations in BNP levels in professional athletes. Materials and Methods: Forty professional athletes who had at least 3 years of a championship background in track and field (aerobic group or body building (resistance group volunteered to participate in the present study. Track and field athletes (n = 20 were requested to run 8 km at 60% to 70% of maximum heart rate. Body building athletes (n = 20 performed a resistance training session of 5 exercises in 3 sets of 10 repetitions at 75% of 1 RM (bench press, seated row, leg extension, leg curl, and leg press. Before and immediately after the exercise, plasma BNP levels of both groups of athletes were measured by PATHFASTTM NT-proBNP assay, an immunochemiluminescent assay using two polyclonal antibodies in sandwich test format, on a PATHFASTTM automated analyzer. Results: Plasma BNP levels immediately following exercise increased significantly as compared with baseline values. Plasma BNP concentrations in the aerobic group were significantly higher than in the resistance group before and after exercise. Moreover, the increase in mean BNP concentrations in aerobic athletes was 7 times more than in resistance athletes. Conclusions: BNP levels in athlete who performed distance exercises increased significantly compared with resistance training. Possibly exercise program type, intensity of exercise, volume of exercise program, and field sport can be factors of changes in BNP levels

  2. Production of gaba (γ - aminobutyric acid) by microorganisms: a review

    OpenAIRE

    Radhika Dhakal; Bajpai, Vivek K.; Kwang-Hyun Baek

    2012-01-01

    GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and als...

  3. Production of gaba (γ - aminobutyric acid) by microorganisms: a review

    OpenAIRE

    Radhika Dhakal; Bajpai, Vivek K.; Kwang-Hyun Baek

    2012-01-01

    GABA (γ-aminobutyric acid) is a four carbon non-protein amino acid that is widely distributed in plants, animals and microorganisms. As a metabolic product of plants and microorganisms produced by the decarboxylation of glutamic acid, GABA functions as an inhibitory neurotransmitter in the brain that directly affects the personality and the stress management. A wide range of traditional foods produced by microbial fermentation contain GABA, in which GABA is safe and eco-friendly, and also has...

  4. Hippocampal extracellular GABA correlates with metabolism in human epilepsy

    OpenAIRE

    Pan, J.W.; Cavus, I.; Kim, J.; Hetherington, H P.; Spencer, D. D.

    2008-01-01

    As the major inhibitory neurotransmitter in human brain, GABA is an important modulator of hyperexcitability in epilepsy patients. Given the high energetic cost of neurotransmission and synaptic activity, GABA concentrations may be hypothesized to correlate with metabolic function. We studied human epilepsy patients undergoing intracranial EEG monitoring for seizure localization to examine microdialysis measures of extracellular GABA (ecGABA), pre-operative MR spectroscopic measures of neuron...

  5. CDKL5 knockout leads to altered inhibitory transmission in the cerebellum of adult mice.

    Science.gov (United States)

    Sivilia, S; Mangano, C; Beggiato, S; Giuliani, A; Torricella, R; Baldassarro, V A; Fernandez, M; Lorenzini, L; Giardino, L; Borelli, A C; Ferraro, L; Calzà, L

    2016-06-01

    Mutations in the X-linked cyclin-dependent kinase-like 5 gene (CDKL5) are associated to severe neurodevelopmental alterations including motor symptoms. In order to elucidate the neurobiological substrate of motor symptoms in CDKL5 syndrome, we investigated the motor function, GABA and glutamate pathways in the cerebellum of CDKL5 knockout female mice. Behavioural data indicate that CDKL5-KO mice displayed impaired motor coordination on the Rotarod test, and altered steps, as measured by the gait analysis using the CatWalk test. A higher reduction in spontaneous GABA efflux, than that in glutamate, was observed in CDKL5-KO mouse cerebellar synaptosomes, leading to a significant increase of spontaneous glutamate/GABA efflux ratio in these animals. On the contrary, there were no differences between groups in K(+) -evoked GABA and glutamate efflux. The anatomical analysis of cerebellar excitatory and inhibitory pathways showed a selective defect of the GABA-related marker GAD67 in the molecular layer in CDKL5-KO mice, while the glutamatergic marker VGLUT1 was unchanged in the same area. Fine cerebellar structural abnormalities such as a reduction of the inhibitory basket 'net' estimated volume and an increase of the pinceau estimated volume were also observed in CDKL5-KO mice. Finally, the BDNF mRNA expression level in the cerebellum, but not in the hippocampus, was reduced compared with WT animals. These data suggest that CDKL5 deletion during development more markedly impairs the establishment of a correct GABAergic cerebellar network than that of glutamatergic one, leading to the behavioural symptoms associated with CDKL5 mutation. PMID:27108663

  6. HSF1 transcriptional activity mediates alcohol induction of Vamp2 expression and GABA release

    Directory of Open Access Journals (Sweden)

    Florence P. Varodayan

    2013-12-01

    Full Text Available Many central synapses are highly sensitive to alcohol, and it is now accepted that short-term alterations in synaptic function may lead to longer term changes in circuit function. The regulation of postsynaptic receptors by alcohol has been well studied, but the mechanisms underlying the effects of alcohol on the presynaptic terminal are relatively unexplored. To identify a pathway by which alcohol regulates neurotransmitter release, we recently investigated the mechanism by which ethanol induces the Vamp2 gene, but not Vamp1, in mouse primary cortical cultures. These two genes encode isoforms of synaptobrevin, a vesicular soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE protein required for synaptic vesicle fusion. We found that alcohol activates the transcription factor heat shock factor 1 (HSF1 to induce Vamp2 gene expression, while Vamp1 mRNA levels remain unaffected. As the Vamp2 gene encodes a SNARE protein, we then investigated whether ethanol exposure and HSF1 transcriptional activity alter neurotransmitter release using electrophysiology. We found that alcohol increased the frequency of γ-aminobutyric acid (GABA-mediated miniature IPSCs via HSF1, but had no effect on mEPSCs. Overall, these data indicate that alcohol induces HSF1 transcriptional activity to trigger a specific coordinated adaptation in GABAergic presynaptic terminals. This mechanism could explain some of the changes in synaptic function that occur soon after alcohol exposure, and may underlie some of the more enduring effects of chronic alcohol intake on local circuit function.

  7. Neurotensin receptor binding levels in basal ganglia are not altered in Huntington's chorea or schizophrenia

    International Nuclear Information System (INIS)

    Autoradiographic techniques were used to examine the distribution and levels of neurotensin receptor binding sites in the basal ganglia and related regions of the human brain. Monoiodo (125I-Tyr3)neurotensin was used as a ligand. High amounts of neurotensin receptor binding sites were found in the substantia nigra pars compacta. Lower but significant quantities of neurotensin receptor binding sites characterized the caudate, putamen, and nucleus accumbens, while very low quantities were seen in both medial and lateral segments of the globus pallidus. In Huntington's chorea, the levels of neurotensin receptor binding sites were found to be comparable to those of control cases. Only slight but not statistically significant decreases in amounts of receptor binding sites were detected in the dorsal part of the head and in the body of caudate nucleus. No alterations in the levels of neurotensin receptor binding sites were observed in the substantia nigra pars compacta and reticulata. These results suggest that a large proportion of neurotensin receptor binding sites in the basal ganglia are located on intrinsic neurons and on extrinsic afferent fibers that do not degenerate in Huntington's disease

  8. GABA-ergic neurons in the leach central nervous system

    International Nuclear Information System (INIS)

    GABA is a candidate for an inhibitory neurotransmitter in the leech central nervous system because of the well-documented inhibitory action of GABA in other invertebrates. To demonstrate that GABA meets the criteria used to identify a substance as a neurotransmitter, the author examined GABA metabolism and synaptic interactions of inhibitory motor neurons in two leech species, Hirudo medicinalis and Haementeria ghilianii. Segmental ganglia of the leech ventral nerve cord and identified inhibitors have the capacity to synthesize GABA when incubated in the presence of the precursor glutamate. Application of GABA to cell bodies of excitatory motor neurons or muscle fibers innervated by the inhibitors hyperpolarizes the membrane potential of the target cell and activates a chloride ion conductance channel, similar to the inhibitory membrane response following intracellular stimulation of the inhibitor. Bicuculline methiodide (5 x 10-5M), GABA receptor antagonist, blocks reversibly the response to applied GABA and the inhibitory synaptic inputs onto the postsynaptic neurons or muscle fibers without interfering with their excitatory inputs. Furthermore, the inhibitors are included among approximately 25 neurons per segmental ganglion that take up GABA by a high affinity uptake system, as revealed by 3H-GABA-autoradiography. The development of the capacities to synthesize and to take up GABA were examined in leech embryos. The embryos are able to synthesize GABA at early stages of the development of the nervous system, before any neurons have extended neutrites

  9. Increased plasma soluble endoglin levels as an indicator of cardiovascular alterations in hypertensive and diabetic patients

    Directory of Open Access Journals (Sweden)

    Martínez-Salgado Carlos

    2010-12-01

    Full Text Available Abstract Background Endoglin is involved in the regulation of endothelial function, but there are no studies concerning its relation with hypertension- and diabetes-associated pathologies. Thus, we studied the relationship between plasma levels of soluble endoglin and cardiovascular alterations associated with hypertension and diabetes. Methods We analyzed 288 patients: 64 with type 2 diabetes, 159 with hypertension and 65 healthy patients. We assessed the relationship of soluble endoglin plasma levels measured by enzyme-linked immunosorbent assay with basal glycemia, glycosylated hemoglobin, blood pressure, endothelial dysfunction (assessed by pressure wave velocity, hypertensive retinopathy (by Keith-Wagener classification, left ventricular hypertrophy (by Cornell and Sokolow indexes, cardiovascular risk and target organ (heart, vascular, kidney damage. Results There are significant correlations between endoglin and glycemia, systolic blood pressure, pulse pressure, pressure wave velocity and electrocardiographically assessed left ventricular hypertrophy. Endoglin levels were significantly higher in patients with diabetes who had nondipper and extreme dipper circadian blood pressure patterns than in dipper circadian patterns, in patients with hypertension and diabetes who had riser pattern than in the other patients, and in patients with diabetes but not hypertension who had extreme dipper pattern than in dipper, nondipper and riser groups. There was also a significant correlation between plasma-soluble endoglin and lower levels of systolic night-day ratio. Higher endoglin levels were found in patients with diabetes who had retinopathy, in patients with diabetes who had a high probability of 10-year cardiovascular risk, and in patients with diabetes and hypertension who had three or more damaged target organs (heart, vessels, kidney than in those with no organs affected. Conclusions This study shows that endoglin is an indicator of

  10. Lactate-Induced Release of GABA in the Ventromedial Hypothalamus Contributes to Counterregulatory Failure in Recurrent Hypoglycemia and Diabetes

    OpenAIRE

    Chan, Owen; Paranjape, Sachin A.; Horblitt, Adam; Zhu, Wanling; Sherwin, Robert S.

    2013-01-01

    Suppression of GABAergic neurotransmission in the ventromedial hypothalamus (VMH) is crucial for full activation of counterregulatory responses to hypoglycemia, and increased γ-aminobutyric acid (GABA) output contributes to counterregulatory failure in recurrently hypoglycemic (RH) and diabetic rats. The goal of this study was to establish whether lactate contributes to raising VMH GABA levels in these two conditions. We used microdialysis to deliver artificial extracellular fluid or l-lactat...

  11. [Cardioprotective effect of GABA derivatives in acute alcohol intoxication].

    Science.gov (United States)

    Perfilova, V N; Tiurenkov, I N; Berestovitskaia, V M; Vasil'eva, O S

    2006-01-01

    Cardioprotective properties of GABA analogs under conditions of acute alcoholic intoxication have been studied using the following functional tests: volume loads, tests for adrenoreactivity, and maximum isometric load. The experiments showed that a 32% aqueous ethanol solution intraperitoneally injected in a dose of 8 g/kg produces a cardiotoxic action, which is manifested by a decrease in the inotropic reserve in load tests. Citrocard (50 mg/kg), phenibut (50 mg/kg), and piracetam (200 mg/kg) prevent the alcohol-induced myocardium injury, as shown by the heart contractility retained on a higher level in the test group than in the control group. PMID:16995433

  12. GABA/benzodiazepine receptor complex in long-sleep and short-sleep mice

    Energy Technology Data Exchange (ETDEWEB)

    Marley, R.J.

    1987-01-01

    LS mice are more sensitive to benzodiazepine-induced anesthesia; however, the two lines do not differ in their hypothermic response to flurazepam. SS mice are more resistant to 3-mercaptopropionic acid-induced seizures and more sensitive to the anticonvulsant effects of benzodiazepines. The various correlates of GABA and benzodiazepine actions probably are the results of different mechanisms of action and/or differential regional control. Bicuculline competition for /sup 3/H-GABA binding sites is greater in SS cerebellar tissue and /sup 3/H-flunitrazepam binding is greater in the mid-brain region of LS mice. GABA enhancement of /sup 3/H-flunitrazepma binding is greater in SS mice. Ethanol also enhances /sup 3/H-flunitrazepam binding and increases the levels of /sup 3/H-flunitrazepam binding above those observed for GABA. Using correlational techniques on data from LS and SS mice and several inbred mouse strains, it was demonstrated that a positive relationship exists between the degree of receptor coupling within the GABA receptor complex and the degree of resistance to seizures.

  13. GABA/benzodiazepine receptor complex in long-sleep and short-sleep mice

    International Nuclear Information System (INIS)

    LS mice are more sensitive to benzodiazepine-induced anesthesia; however, the two lines do not differ in their hypothermic response to flurazepam. SS mice are more resistant to 3-mercaptopropionic acid-induced seizures and more sensitive to the anticonvulsant effects of benzodiazepines. The various correlates of GABA and benzodiazepine actions probably are the results of different mechanisms of action and/or differential regional control. Bicuculline competition for 3H-GABA binding sites is greater in SS cerebellar tissue and 3H-flunitrazepam binding is greater in the mid-brain region of LS mice. GABA enhancement of 3H-flunitrazepma binding is greater in SS mice. Ethanol also enhances 3H-flunitrazepam binding and increases the levels of 3H-flunitrazepam binding above those observed for GABA. Using correlational techniques on data from LS and SS mice and several inbred mouse strains, it was demonstrated that a positive relationship exists between the degree of receptor coupling within the GABA receptor complex and the degree of resistance to seizures

  14. Dexamethasone treatment alters insulin, leptin, and adiponectin levels in male mice as observed in DIO but does not lead to alterations of metabolic phenotypes in the offspring

    OpenAIRE

    Bönisch, Clemens; Irmler, Martin; Brachthäuser, Laura; Neff, Frauke; Bamberger, Mareike T.; Marschall, Susan; Hrabě de Angelis, Martin; Beckers, Johannes

    2015-01-01

    Epigenetic inheritance (EI) of metabolic phenotypes via the paternal lineage has been shown in rodent models of diet-induced obesity (DIO). However, the factors involved in soma-to-germline information transfer remain elusive. Here, we address the role of alterations in insulin, leptin, and adiponectin levels for EI of metabolic phenotypes by treating C57BL/6NTac male mice (F0) with the synthetic glucocorticoid dexamethasone and generating offspring (F1) either by in vitro fertilization or by...

  15. Fetal rat metabonome alteration by prenatal caffeine ingestion probably due to the increased circulatory glucocorticoid level and altered peripheral glucose and lipid metabolic pathways

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yansong [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan University, Wuhan, 430071 (China); Xu, Dan [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan University, Wuhan, 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan, 430071 (China); Feng, Jianghua, E-mail: jianghua.feng@xmu.edu.cn [Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan, 430071 (China); Department of Electronic Science, Fujian Provincial Key Laboratory of Plasma and Magnetic Resonance, Xiamen University, Xiamen, 361005 (China); Kou, Hao; Liang, Gai [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan University, Wuhan, 430071 (China); Yu, Hong; He, Xiaohua; Zhang, Baifang; Chen, Liaobin [Research Center of Food and Drug Evaluation, Wuhan University, Wuhan, 430071 (China); Magdalou, Jacques [UMR 7561 CNRS-Nancy Université, Faculté de Médicine, Vandoeuvre-lès-Nancy (France); Wang, Hui, E-mail: wanghui19@whu.edu.cn [Department of Pharmacology, Basic Medical School of Wuhan University, Wuhan University, Wuhan, 430071 (China); Research Center of Food and Drug Evaluation, Wuhan University, Wuhan, 430071 (China)

    2012-07-15

    The aims of this study were to clarify the metabonome alteration in fetal rats after prenatal caffeine ingestion and to explore the underlying mechanism pertaining to the increased fetal circulatory glucocorticoid (GC). Pregnant Wistar rats were daily intragastrically administered with different doses of caffeine (0, 20, 60 and 180 mg/kg) from gestational days (GD) 11 to 20. Metabonome of fetal plasma and amniotic fluid on GD20 were analyzed by {sup 1}H nuclear magnetic resonance-based metabonomics. Gene and protein expressions involved in the GC metabolism, glucose and lipid metabolic pathways in fetal liver and gastrocnemius were measured by real-time RT-PCR and immunohistochemistry. Fetal plasma metabonome were significantly altered by caffeine, which presents as the elevated α- and β‐glucose, reduced multiple lipid contents, varied apolipoprotein contents and increased levels of a number of amino acids. The metabonome of amniotic fluids showed a similar change as that in fetal plasma. Furthermore, the expressions of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD-2) were decreased, while the level of blood GC and the expressions of 11β-HSD-1 and glucocorticoid receptor (GR) were increased in fetal liver and gastrocnemius. Meanwhile, the expressions of insulin-like growth factor 1 (IGF-1), IGF-1 receptor and insulin receptor were decreased, while the expressions of adiponectin receptor 2, leptin receptors and AMP-activated protein kinase α2 were increased after caffeine treatment. Prenatal caffeine ingestion characteristically change the fetal metabonome, which is probably attributed to the alterations of glucose and lipid metabolic pathways induced by increased circulatory GC, activated GC metabolism and enhanced GR expression in peripheral metabolic tissues. -- Highlights: ► Prenatal caffeine ingestion altered the metabonome of IUGR fetal rats. ► Caffeine altered the glucose and lipid metabolic pathways of IUGR fetal rats. ► Prenatal caffeine

  16. Fetal rat metabonome alteration by prenatal caffeine ingestion probably due to the increased circulatory glucocorticoid level and altered peripheral glucose and lipid metabolic pathways

    International Nuclear Information System (INIS)

    The aims of this study were to clarify the metabonome alteration in fetal rats after prenatal caffeine ingestion and to explore the underlying mechanism pertaining to the increased fetal circulatory glucocorticoid (GC). Pregnant Wistar rats were daily intragastrically administered with different doses of caffeine (0, 20, 60 and 180 mg/kg) from gestational days (GD) 11 to 20. Metabonome of fetal plasma and amniotic fluid on GD20 were analyzed by 1H nuclear magnetic resonance-based metabonomics. Gene and protein expressions involved in the GC metabolism, glucose and lipid metabolic pathways in fetal liver and gastrocnemius were measured by real-time RT-PCR and immunohistochemistry. Fetal plasma metabonome were significantly altered by caffeine, which presents as the elevated α- and β‐glucose, reduced multiple lipid contents, varied apolipoprotein contents and increased levels of a number of amino acids. The metabonome of amniotic fluids showed a similar change as that in fetal plasma. Furthermore, the expressions of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD-2) were decreased, while the level of blood GC and the expressions of 11β-HSD-1 and glucocorticoid receptor (GR) were increased in fetal liver and gastrocnemius. Meanwhile, the expressions of insulin-like growth factor 1 (IGF-1), IGF-1 receptor and insulin receptor were decreased, while the expressions of adiponectin receptor 2, leptin receptors and AMP-activated protein kinase α2 were increased after caffeine treatment. Prenatal caffeine ingestion characteristically change the fetal metabonome, which is probably attributed to the alterations of glucose and lipid metabolic pathways induced by increased circulatory GC, activated GC metabolism and enhanced GR expression in peripheral metabolic tissues. -- Highlights: ► Prenatal caffeine ingestion altered the metabonome of IUGR fetal rats. ► Caffeine altered the glucose and lipid metabolic pathways of IUGR fetal rats. ► Prenatal caffeine ingestion

  17. Alteration on the serum IL-2, IL-6 and receptors levels in patients with chronic glomerulonephritis

    International Nuclear Information System (INIS)

    Objective: To investigate the alteration and clinical significance of serum IL-2, IL-6 and receptors levels in Patients with Chronic Glomerulonephritis (CGN). Methods: Serum IL-2, IL-6 levels were determined by the bioassay methods, Serum sIL-2R, sIL-6R were determined by ELISA analysis, mIL-2R were determined by immunofluorescence assay in patient with CGN, and the data were compared with that in the normal controls group. Results: It was found that the levels of serum IL-6, sIL-2R and sIL-6R were significantly higher in CGN than that in controls (P < 0.0001), respectively. While serum IL-2 markedly lower in CGN than in the controls (P < 0.0001) and mIL-2R in CGN have no apparent difference with that in the controls. There was a positive correlation between IL-6 and BUN (P < 0.005), positive correlation between sIL6R and SCR. (P < 0.005), While there were positive correlation between sIL-2R and BUN. SCr(P < 0.05; P < 0.005) respectively, negative correlation between sIL-2R and urinary protein (P < 0.05). Conclusion: IL-2, sIL-2R, IL-6, sIL-6R play an important role in the pathogenesis of CGN, could reflect severity degree and prognosis of CGN. While low levels of IL-2 attributes to cell immune states of patients with CGN was depressed

  18. Reduction of GABA/sub B/ receptor binding induced by climbing fiber degeneration in the rat cerebellum

    International Nuclear Information System (INIS)

    When the rat cerebellar climbing fibers degenerated, as induced by lesioning the inferior olive with 3-acetylpyridine (3-AP), GABA/sub B/ receptor binding determined with 3H-(+/-)baclofen was reduced in the cerebellum but not in the cerebral cortex of rats. Computer analysis of saturation data revealed two components of the binding sites, and indicated that decrease of the binding in the cerebellum was due to reduction in receptor density, mainly of the high-affinity sites, the B/sub max/ of which was reduced to one-third that in the control animals. In vitro treatment with 3-AP, of the membranes prepared from either the cerebellum or the cerebral cortex, induced no alteration in the binding sites, thereby indicating that the alteration of GABA/sub B/ sites induced by in vivo treatment with 3-AP is not due to a direct action of 3-AP on the receptor. GABA/sub A/ and benzodiazepine receptor binding labelled with 3H-muscimol and 3H-diazepam, respectively, in both of brain regions was not affected by destruction of the inferior olive. These results provide evidence that some of the GABA/sub B/ sites but neither GABA/sub A/ nor benzodiazepine receptors in the cerebellum are located at the climbing fiber terminals. 28 references, 4 figures, 2 tables

  19. Reduction of GABA/sub B/ receptor binding induced by climbing fiber degeneration in the rat cerebellum

    Energy Technology Data Exchange (ETDEWEB)

    Kato, K.; Fukuda, H.

    1985-07-22

    When the rat cerebellar climbing fibers degenerated, as induced by lesioning the inferior olive with 3-acetylpyridine (3-AP), GABA/sub B/ receptor binding determined with /sup 3/H-(+/-)baclofen was reduced in the cerebellum but not in the cerebral cortex of rats. Computer analysis of saturation data revealed two components of the binding sites, and indicated that decrease of the binding in the cerebellum was due to reduction in receptor density, mainly of the high-affinity sites, the B/sub max/ of which was reduced to one-third that in the control animals. In vitro treatment with 3-AP, of the membranes prepared from either the cerebellum or the cerebral cortex, induced no alteration in the binding sites, thereby indicating that the alteration of GABA/sub B/ sites induced by in vivo treatment with 3-AP is not due to a direct action of 3-AP on the receptor. GABA/sub A/ and benzodiazepine receptor binding labelled with /sup 3/H-muscimol and /sup 3/H-diazepam, respectively, in both of brain regions was not affected by destruction of the inferior olive. These results provide evidence that some of the GABA/sub B/ sites but neither GABA/sub A/ nor benzodiazepine receptors in the cerebellum are located at the climbing fiber terminals. 28 references, 4 figures, 2 tables.

  20. Mouse Brain PSA-NCAM Levels Are Altered by Graded-Controlled Cortical Impact Injury

    Directory of Open Access Journals (Sweden)

    Craig S. Budinich

    2012-01-01

    Full Text Available Traumatic brain injury (TBI is a worldwide endemic that results in unacceptably high morbidity and mortality. Secondary injury processes following primary injury are composed of intricate interactions between assorted molecules that ultimately dictate the degree of longer-term neurological deficits. One comparatively unexplored molecule that may contribute to exacerbation of injury or enhancement of recovery is the posttranslationally modified polysialic acid form of neural cell adhesion molecule, PSA-NCAM. This molecule is a critical modulator of central nervous system plasticity and reorganization after injury. In this study, we used controlled cortical impact (CCI to produce moderate or severe TBI in the mouse. Immunoblotting and immunohistochemical analysis were used to track the early (2, 24, and 48 hour and late (1 and 3 week time course and location of changes in the levels of PSA-NCAM after TBI. Variable and heterogeneous short- and long-term increases or decreases in expression were found. In general, alterations in PSA-NCAM levels were seen in the cerebral cortex immediately after injury, and these reductions persisted in brain regions distal to the primary injury site, especially after severe injury. This information provides a starting point to dissect the role of PSA-NCAM in TBI-related pathology and recovery.

  1. Venous plasma levels of endothelin-1 are not altered immediately after nitroglycerin infusion in healthy subjects

    DEFF Research Database (Denmark)

    Thomsen, L L; Iversen, Helle Klingenberg; Emmeluth, C;

    1995-01-01

    before and immediately (5-30 s) after 80 min infusion of NTG (glyceryl trinitrate) or saline in 12 healthy subjects. On two different days separated by at least 1 week, NTG in four different doses, 0.015, 0.25, 1.0, and 2.0 micrograms. kg-1. min-1, or placebo (isotonic saline) was infused successively...... for 20 min each dose. During the infusion blood pressure and heart rate were measured. NTG infusion significantly decreased systolic blood pressure from 112.4 to 103.4 mmHg and pulse pressure from 39.3 to 29.5 mmHg. Heart rate increased from 62.7 to 73.1 beats. min-1. No changes in endothelin-1 plasma...... levels were induced by NTG infusion (2.4 pg.ml-1 before NTG vs. 2.7 pg.ml-1 after NTG) and placebo infusion also did not affect plasma endothelin-1. It is concluded that venous plasma levels of endothelin-1 are not altered immediately after NTG infusion....

  2. γ-Aninobutyric acid (GABA suppresses antigen-specific immune responses in ovalbumin γ(OVA-immunized BALB/c mice

    Directory of Open Access Journals (Sweden)

    Tohru Sakai

    2005-01-01

    Full Text Available γ-Aminobutruic acid (GABA is known to be a ubiquitous inhibitory neurotransmitter in the central nervous system. Furthermore, recent studies have shown that GABA modulates cardiovascular and respiratory functions. In this study, we examined the effect of GABA on antigen (Ag-specific immune responses and elucidated the mechanisms underlying those effects in ovalbumin (OVA-immunized BALB/c mice. OVA-specific proliferative responses were decreased in mice that had been administered 20 mg/kg GABA compared to those in control mice without reduction in responses to anti-CD3 monoclonal (mAb. The levels of OVA-specific IgG, IgG1 and IgG2a were also decreased in mice that had been administered GABA. However, GABA administration did not influence the TNP-specific IgM and IgG levels. Ag-presenting activity of CD11c+ dendritic cells from GABA-treated mice was less than that of cells from control mice. These results suggest that the suppressive effect of GABA on Ag-specific immune responses contributes to the reduction of antigen-presenting function on CD11c+ dendritic cells.

  3. GABA and glutamate pathways are spatially and developmentally affected in the brain of Mecp2-deficient mice.

    Directory of Open Access Journals (Sweden)

    Rita El-Khoury

    Full Text Available Proper brain functioning requires a fine-tuning between excitatory and inhibitory neurotransmission, a balance maintained through the regulation and release of glutamate and GABA. Rett syndrome (RTT is a rare genetic disorder caused by mutations in the methyl-CpG binding protein 2 (MECP2 gene affecting the postnatal brain development. Dysfunctions in the GABAergic and glutamatergic systems have been implicated in the neuropathology of RTT and a disruption of the balance between excitation and inhibition, together with a perturbation of the electrophysiological properties of GABA and glutamate neurons, were reported in the brain of the Mecp2-deficient mouse. However, to date, the extent and the nature of the GABA/glutamate deficit affecting the Mecp2-deficient mouse brain are unclear. In order to better characterize these deficits, we simultaneously analyzed the GABA and glutamate levels in Mecp2-deficient mice at 2 different ages (P35 and P55 and in several brain areas. We used a multilevel approach including the quantification of GABA and glutamate levels, as well as the quantification of the mRNA and protein expression levels of key genes involved in the GABAergic and glutamatergic pathways. Our results show that Mecp2-deficient mice displayed regional- and age-dependent variations in the GABA pathway and, to a lesser extent, in the glutamate pathway. The implication of the GABA pathway in the RTT neuropathology was further confirmed using an in vivo treatment with a GABA reuptake inhibitor that significantly improved the lifespan of Mecp2-deficient mice. Our results confirm that RTT mouse present a deficit in the GABAergic pathway and suggest that GABAergic modulators could be interesting therapeutic agents for this severe neurological disorder.

  4. [Anti-arrhythmic properties of GABA and GABA-ergic system activators].

    Science.gov (United States)

    Tiurenkov, I N; Perfilova, V N

    2002-01-01

    Clinical and experimental data available in the literature are summarized, which are indicative of the antiarrhythmogenic properties of GABA and substances possessing GABA-positive activity (phenibut, piracetam, sodium hydroxybutyrate, lithium hydroxybutyrate, etc.). The antiarrhythmic effects are manifested in various cases of the heart rhythm violation. The mechanism of this action is related to activation of the central and peripheral retarding GABAergic system, as well as to antihypoxant, antioxidant, and antistressor effects. PMID:12025796

  5. Effects of Altered Levels of Extracellular Superoxide Dismutase and Irradiation on Hippocampal Neurogenesis in Female Mice

    International Nuclear Information System (INIS)

    Purpose: Altered levels of extracellular superoxide dismutase (EC-SOD) and cranial irradiation have been shown to affect hippocampal neurogenesis. However, previous studies were only conducted in male mice, and it was not clear if there was a difference between males and females. Therefore, female mice were studied and the results compared with those generated in male mice from an earlier study. Methods and Materials: Female wild-type, EC-SOD-null (KO), and EC-SOD bigenic mice with neuronal-specific expression of EC-SOD (OE) were subjected to a single dose of 5-Gy gamma rays to the head at 8 weeks of age. Progenitor cell proliferation, differentiation, and long-term survival of newborn neurons were determined. Results: Similar to results from male mice, EC-SOD deficiency and irradiation both resulted in significant reductions in mature newborn neurons in female mice. EC-SOD deficiency reduced long-term survival of newborn neurons whereas irradiation reduced progenitor cell proliferation. Overexpression of EC-SOD corrected the negative impacts from EC-SOD deficiency and irradiation and normalized the production of newborn neurons in OE mice. Expression of neurotrophic factors brain-derived neurotrophic factor and neurotrophin-3 were significantly reduced by irradiation in wild-type mice, but the levels were not changed in KO and OE mice even though both cohorts started out with a lower baseline level. Conclusion: In terms of hippocampal neurogenesis, EC-SOD deficiency and irradiation have the same overall effects in males and females at the age the studies were conducted

  6. Altered intracellular pH regulation in cells with high levels of P-glycoprotein expression.

    Science.gov (United States)

    Young, Gregory; Reuss, Luis; Altenberg, Guillermo A

    2011-01-01

    P-glycoprotein is an ATP-binding-cassette transporter that pumps many structurally unrelated drugs out of cells through an ATP-dependent mechanism. As a result, multidrug-resistant cells that overexpress P-glycoprotein have reduced intracellular steady-state levels of a variety of chemotherapeutic agents. In addition, increased cytosolic pH has been a frequent finding in multidrug-resistant cells that express P-glycoprotein, and it has been proposed that this consequence of P-glycoprotein expression may contribute to the lower intracellular levels of chemotherapeutic agents. In these studies, we measured intracellular pH and the rate of acid extrusion in response to an acid load in two cells with very different levels of P-glycoprotein expression: V79 parental cells and LZ-8 multidrug resistant cells. Compared to the wild-type V79 cells, LZ-8 cells have a lower intracellular pH and a slower recovery of intracellular pH after an acid load. The data also show that LZ-8 cells have reduced ability to extrude acid, probably due to a decrease in Na(+)/H(+) exchanger activity. The alterations in intracellular pH and acid extrusion in LZ-8 cells are reversed by 24-h exposure to the multidrug-resistance modulator verapamil. The lower intracellular pH in LZ-8 indicates that intracellular alkalinization is not necessary for multidrug resistance. The reversal by verapamil of the decreased acid-extrusion suggests that P-glycoprotein can affect other membrane transport mechanism. PMID:22003434

  7. Effects of Altered Levels of Extracellular Superoxide Dismutase and Irradiation on Hippocampal Neurogenesis in Female Mice

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Yani [Department of Neurology and Neurological Sciences, Stanford University, Stanford, California (United States); Leu, David [Department of Neurology and Neurological Sciences, Stanford University, Stanford, California (United States); Palo Alto Institute of Research and Education, Palo Alto, California (United States); Chui, Jennifer [Department of Neurology and Neurological Sciences, Stanford University, Stanford, California (United States); Fike, John R. [Departments of Neurosurgery and Radiation Oncology, University of California, San Francisco, California (United States); Huang, Ting-Ting, E-mail: tthuang@stanford.edu [Department of Neurology and Neurological Sciences, Stanford University, Stanford, California (United States); VA Palo Alto Health Care System, Palo Alto, California (United States)

    2013-11-15

    Purpose: Altered levels of extracellular superoxide dismutase (EC-SOD) and cranial irradiation have been shown to affect hippocampal neurogenesis. However, previous studies were only conducted in male mice, and it was not clear if there was a difference between males and females. Therefore, female mice were studied and the results compared with those generated in male mice from an earlier study. Methods and Materials: Female wild-type, EC-SOD-null (KO), and EC-SOD bigenic mice with neuronal-specific expression of EC-SOD (OE) were subjected to a single dose of 5-Gy gamma rays to the head at 8 weeks of age. Progenitor cell proliferation, differentiation, and long-term survival of newborn neurons were determined. Results: Similar to results from male mice, EC-SOD deficiency and irradiation both resulted in significant reductions in mature newborn neurons in female mice. EC-SOD deficiency reduced long-term survival of newborn neurons whereas irradiation reduced progenitor cell proliferation. Overexpression of EC-SOD corrected the negative impacts from EC-SOD deficiency and irradiation and normalized the production of newborn neurons in OE mice. Expression of neurotrophic factors brain-derived neurotrophic factor and neurotrophin-3 were significantly reduced by irradiation in wild-type mice, but the levels were not changed in KO and OE mice even though both cohorts started out with a lower baseline level. Conclusion: In terms of hippocampal neurogenesis, EC-SOD deficiency and irradiation have the same overall effects in males and females at the age the studies were conducted.

  8. Chronic alteration in phosphatidylinositol 4,5-biphosphate levels regulates capsaicin and mustard oil responses.

    Science.gov (United States)

    Patil, Mayur J; Belugin, Sergei; Akopian, Armen N

    2011-06-01

    There is an agreement that acute (in minutes) hydrolysis and accumulation of phosphatidylinositol 4,5-bisphosphate (PIP(2) ) modulate TRPV1 and TRPA1 activities. Because inflammation results in PIP(2) depletion, persisting for long periods (hours to days) in pain models and in the clinic, we examined whether chronic depletion and accumulation of PIP(2) affect capsaicin (CAP) and mustard oil (MO) responses. In addition, we wanted to evaluate whether the effects of PIP(2) depend on TRPV1 and TRPA1 coexpression and whether the PIP(2) actions vary in expression cells vs. sensory neurons. Chronic PIP(2) production was stimulated by overexpression of phosphatidylinositol-4-phosphate-5-kinase, and PIP(2) -specific phospholipid 5'-phosphatase was selected to reduce plasma membrane levels of PIP(2) . Our results demonstrate that CAP (100 nM) responses and receptor tachyphylaxis are not significantly influenced by chronic changes in PIP(2) levels in wild-type (WT) or TRPA1 null-mutant sensory neurons as well as CHO cells expressing TRPV1 alone or with TRPA1. However, low concentrations of CAP (20 nM) produced a higher response after PIP(2) depletion in cells containing TRPV1 alone but not TRPV1 together with TRPA1. MO (25 μM) responses were also not affected by PIP(2) in WT sensory neurons and cells coexpressing TRPA1 and TRPV1. In contrast, PIP(2) reduction leads to pronounced tachyphylaxis to MO in cells with both channels. Chronic effect of PIP(2) on TRPA1 activity depends on presence of the TRPV1 channel and cell type (CHO vs. sensory neurons). In summary, chronic alterations in PIP(2) levels regulate magnitude of CAP and MO responses as well as MO tachyphylaxis. This regulation depends on coexpression profile of TRPA1 and TRPV1 and cell type. PMID:21337373

  9. GABA binding to an insect GABA receptor: a molecular dynamics and mutagenesis study.

    Science.gov (United States)

    Ashby, Jamie A; McGonigle, Ian V; Price, Kerry L; Cohen, Netta; Comitani, Federico; Dougherty, Dennis A; Molteni, Carla; Lummis, Sarah C R

    2012-11-21

    RDL receptors are GABA-activated inhibitory Cys-loop receptors found throughout the insect CNS. They are a key target for insecticides. Here, we characterize the GABA binding site in RDL receptors using computational and electrophysiological techniques. A homology model of the extracellular domain of RDL was generated and GABA docked into the binding site. Molecular dynamics simulations predicted critical GABA binding interactions with aromatic residues F206, Y254, and Y109 and hydrophilic residues E204, S176, R111, R166, S176, and T251. These residues were mutated, expressed in Xenopus oocytes, and their functions assessed using electrophysiology. The data support the binding mechanism provided by the simulations, which predict that GABA forms many interactions with binding site residues, the most significant of which are cation-π interactions with F206 and Y254, H-bonds with E204, S205, R111, S176, T251, and ionic interactions with R111 and E204. These findings clarify the roles of a range of residues in binding GABA in the RDL receptor, and also show that molecular dynamics simulations are a useful tool to identify specific interactions in Cys-loop receptors. PMID:23200041

  10. Neurotransmitters and brain maturation: early paracrine actions of GABA and glutamate modulate neuronal migration.

    OpenAIRE

    Manent, Jean-Bernard; Represa, Alfonso

    2007-01-01

    International audience Migration of neurons from their birthplace to their final destination is an extremely important step in brain maturation, and cortical migration disorders are the most common brain developmental alteration observed in human patients. Among the mechanisms that govern neuronal migration, the neurotransmitters GABA and glutamate deserve particular attention: 1) neurotransmitters and receptors are expressed early in the developing brain, 2) neurotransmitters may act as p...

  11. Columnar Architecture Sculpted by GABA Circuits in Developing Cat Visual Cortex

    OpenAIRE

    Hensch, Takao K.; Stryker, Michael P.

    2004-01-01

    The mammalian visual cortex is organized into columns. Here, we examine cortical influences upon developing visual afferents in the cat by altering intrinsic γ-aminobutyric acid (GABA)–mediated inhibition with benzodiazepines. Local enhancement by agonist (diazepam) infusion did not perturb visual responsiveness, but did widen column spacing. An inverse agonist (DMCM) produced the opposite effect. Thus, intracortical inhibitory circuits shape the geometry of incoming thalamic arbors, suggesti...

  12. Alterations of T cell activation signalling and cytokine production by postmenopausal estrogen levels

    Directory of Open Access Journals (Sweden)

    Taylor Douglas D

    2009-03-01

    Full Text Available Abstract Background Immunosenescence is an age-associated disorder occurring primarily in T cell compartments, including altered subset composition, functions, and activation. In women, evidence implicates diminished estrogen in the postmenopausal period as a contributing factor to diminished T cell responsiveness. Since hypoestrogenism is present in postmenopausal women, our objective focused on whether T cell activation, defined as signalling molecule expressions and activation, and function, identified as IL-2 production, were affected by low estrogen. Methods Using Jurkat 6.1 T cells, consequences of 4 pg/ml (corresponding to postmenopausal levels or 40 pg/ml (premenopausal levels of estradiol (E2 were analyzed on signalling proteins, CD3-zeta, JAK2, and JAK3, determined by Western immunoblotting. These consequences were correlated with corresponding gene expressions, quantified by real time-polymerase chain reaction. Tyrosine phosphorylation of CD3-zeta was defined by immunoprecipitation and western immunoblotting following activation by T cell receptor (TcR cross-linking. CD3-zeta expression and modulation was also confirmed in T cells from pre- and postmenopausal women. To assess functional consequences, IL-2 production, induced by PMA and ionomycin, was determined using enzyme-linked immunosorbent spot assay (ELISpot. Results At 40 pg/ml E2, the level of signalling protein CD3-zeta was elevated 1.57-fold, compared with cells exposed to 4 pg/ml E2. The CD3-zeta proteins also exhibited altered levels of activation-induced phosphorylation in the presence of 40 pg/ml E2 versus 4 pg/ml: 23 kD phosphorylated form increased 2.64-fold and the 21 kD form was elevated 2.95-fold. Examination of kinases associated with activation signalling also demonstrated that, in the presence of 40 pg/ml E2, JAK2 protein expression was increased 1.64-fold (p 2 (2.39, 2.01, and 2.21 fold, respectively versus 4 pg/ml. These findings were confirmed in vivo, since T

  13. How and why does tomato accumulate a large amount of GABA in the fruit?

    OpenAIRE

    Mariko eTakayama; Hiroshi eEzura

    2015-01-01

    γ-Aminobutyric acid (GABA) has received much attention as a health-promoting functional compound, and several GABA-enriched foods have been commercialized. In higher plants, GABA is primarily metabolized via a short pathway called the GABA shunt. The GABA shunt bypasses two steps (the oxidation of α-ketoglutarate to succinate) of the tricarboxylic acid (TCA) cycle via reactions catalysed by three enzymes: glutamate decarboxylase (GAD), GABA transaminase (GABA-T) and succinic semialdehyde dehy...

  14. Glutamate and GABA in appetite regulation

    Directory of Open Access Journals (Sweden)

    Teresa Cardoso Delgado

    2013-08-01

    Full Text Available Appetite is regulated by a coordinated interplay between gut, adipose tissue and brain. A primary site for the regulation of appetite is the hypothalamus where interaction between orexigenic neurons, expressing Neuropeptide Y/Agouti-related protein, and anorexigenic neurons, expressing Pro-opiomelanocortin cocaine/Amphetamine-related transcript, controls energy homeostasis. Within the hypothalamus, several peripheral signals have been shown to modulate the activity of these neurons, including the orexigenic peptide ghrelin and the anorexigenic hormones insulin and leptin. In addition to the accumulated knowledge on neuropeptide signaling, presence and function of amino acid neurotransmitters in key hypothalamic neurons brought a new light into appetite regulation. Therefore, the principal aim of this review will be to describe the current knowledge of the role of amino acid neurotransmitters in the mechanism of neuronal activation during appetite regulation and the associated neuronal-astrocytic metabolic coupling mechanisms.Glutamate and GABA dominate synaptic transmission in the hypothalamus and administration of their receptors agonists into hypothalamic nuclei stimulates feeding. By using 13C High-Resolution Magic Angle Spinning Nuclear Magnetic Resonance spectroscopy based analysis, the Cerdán group has shown that increased neuronal firing in mice hypothalamus, as triggered by appetite during the feeding-fasting paradigm, may stimulate the use of lactate as neuronal fuel leading to increased astrocytic glucose consumption and glycolysis. Moreover, fasted mice showed increased hypothalamic [2-13C]GABA content, which may be explained by the existence of GABAergic neurons in key appetite regulation hypothalamic nuclei. Interestingly, increased [2-13C]GABA concentration in the hypothalamus of fasted animals appears to result mainly from reduction in GABA metabolizing pathways, rather than increased GABA synthesis by augmented activity of the

  15. Mechanisms of hydrothermal alteration in a granitic rock. Consequences for high-level radioactive waste disposal

    International Nuclear Information System (INIS)

    The study of hydrothermal alteration in the Auriat granitic rock (France, Massif-Central) has evidenced three main events: - a pervasive chloritisation of biotites in some parts of the drill-core, - an alteration localized around subvertical cracks and superimposed on previously chloritized or unaltered granite, - an alteration localized around subhorizontal cracks cross-cutting the preceding ones. The second type of alteration, produced by a geothermal system, gives the most interesting results to be applied to the nuclear radwaste disposal problem. Among primary minerals of granite, only biotite (or chlorite) and oligoclase are intensively altered. Therefore, the chemical composition of these minerals induces the nature of secondary parageneses. These, associated to the subvertical cracks network, indicate a thermal gradient of 150 C/Km. The geochemical code has allowed to corroborate that the thermal gradient was responsible for the occurrence of different parageneses with depth. Moreover, it was shown that the variable mineralogy around cracks was due to a thermal profile established at equilibrium between the rock and the fluid. Therefore, the extent of the alteration was proportional to the thermal power of the fluid. A dissolution and next a precipitation phase of new minerals characterize hydrothermal alteration, which is due to the thermal power emitted by radioactive waste and linked with the evolution of temperature during time. This alteration provokes two favourable events to storage: decrease of rock porosity and increase of sorption capacity

  16. High levels of circulating extracellular vesicles with altered expression and function during pregnancy.

    Science.gov (United States)

    Nardi, Fabiola da Silva; Michelon, Tatiana Ferreira; Neumann, Jorge; Manvailer, Luis Felipe Santos; Wagner, Bettina; Horn, Peter A; Bicalho, Maria da Graça; Rebmann, Vera

    2016-07-01

    Extracellular vesicles (EVs) are widely considered important modulators of cell-cell communication and may interact with target cells locally and on a systemic level. Several studies had shown that circulating EVs' levels are increased during pregnancy. However, EVs characteristics, composition and biological functions in pregnancy still need to be clarified. This study aims to determine if circulating EVs during pregnancy are modified regarding levels, markers and cytokine profile as well as their reactivity towards peripheral blood cells. 26 pregnant women (PW) being in the second gestational trimester and 59 non-pregnant women (NPW) were investigated. EVs enrichment was performed by ExoQuick™ or ultracentrifugation; nanoparticle tracking analysis, SDS-PAGE followed by Western Blotting and densitometry, and IFN-γ, IL-10 and TGF-β1 ELISA for EVs characterization; imaging flow cytometry to analyze EVs' uptake by peripheral blood cells and flow cytometry were performed to analyze EVs function regarding induction of caspase-3 activity. Circulating EVs' levels were increased during pregnancy [26.9×10(6)EVs/ml (range: 6.4-46.3); p=0.003] vs NPW [18.9×10(6)EVs/ml (range: 2.5-61.3)]. Importantly, the immunosuppressive TGF-β1 and IL-10 cytokine cargo were increased in EVs of PW even after normalization to 1 million EVs [TGF-β1: 0.25pg/10(6)EVs (range: 0.0-2.0); p<0.0001] and [IL-10: 0.21pg/10(6)EVs (range: 0.0-16.8); p=0.006] vs NPW. Although EVs derived from non-pregnant and pregnant women were taken up by NK cells, the latter exclusively enhanced the caspase-3 activity in CD56(dim) NK cells (8.2±0.9; p=0.02). The qualitative and quantitative pregnancy-related alterations of circulating EVs provide first hints for an immune modulating role of circulating EVs during pregnancy. PMID:27005781

  17. Impact of exogenous GABA treatments on endogenous GABA metabolism in anthurium cut flowers in response to postharvest chilling temperature.

    Science.gov (United States)

    Aghdam, Morteza Soleimani; Naderi, Roohangiz; Jannatizadeh, Abbasali; Babalar, Mesbah; Sarcheshmeh, Mohammad Ali Askari; Faradonbe, Mojtaba Zamani

    2016-09-01

    Anthurium flowers are susceptible to chilling injury, and the optimum storage temperature is 12.5-20 °C. The γ-aminobutyric acid (GABA) shunt pathway may alleviate chilling stress in horticultural commodities by providing energy (ATP), reducing molecules (NADH), and minimizing accumulation of reactive oxygen species (ROS). In this experiment, the impact of a preharvest spray treatment with 1 mM GABA and postharvest treatment of 5 mM GABA stem-end dipping on GABA shunt pathway activity of anthurium cut flowers (cv. Sirion) in response to cold storage (4 °C for 21 days) was investigated. GABA treatments resulted in lower glutamate decarboxylase (GAD) and higher GABA transaminase (GABA-T) activities in flowers during cold storage, which was associated with lower GABA content and coincided with higher ATP content. GABA treatments also enhanced accumulation of endogenous glycine betaine (GB) in flowers during cold storage, as well as higher spathe relative water content (RWC). These findings suggest that GABA treatments may alleviate chilling injury of anthurium cut flowers by enhancing GABA shunt pathway activity leading to provide sufficient ATP and promoting endogenous GB accumulation. PMID:27135813

  18. Genetic KCa3.1-deficiency produces locomotor hyperactivity and alterations in cerebral monoamine levels.

    Directory of Open Access Journals (Sweden)

    Kate Lykke Lambertsen

    Full Text Available BACKGROUND: The calmodulin/calcium-activated K(+ channel KCa3.1 is expressed in red and white blood cells, epithelia and endothelia, and possibly central and peripheral neurons. However, our knowledge about its contribution to neurological functions and behavior is incomplete. Here, we investigated whether genetic deficiency or pharmacological activation of KCa3.1 change behavior and cerebral monoamine levels in mice. METHODOLOGY/PRINCIPAL FINDINGS: In the open field test, KCa3.1-deficiency increased horizontal activity, as KCa3.1(-/- mice travelled longer distances (≈145% of KCa3.1(+/+ and at higher speed (≈1.5-fold of KCa3.1(+/+. Working memory in the Y-maze was reduced by KCa3.1-deficiency. Motor coordination on the rotarod and neuromuscular functions were unchanged. In KCa3.1(-/- mice, HPLC analysis revealed that turn-over rates of serotonin were reduced in frontal cortex, striatum and brain stem, while noradrenalin turn-over rates were increased in the frontal cortex. Dopamine turn-over rates were unaltered. Plasma catecholamine and corticosterone levels were unaltered. Intraperitoneal injections of 10 mg/kg of the KCa3.1/KCa2-activator SKA-31 reduced rearing and turning behavior in KCa3.1(+/+ but not in KCa3.1(-/- mice, while 30 mg/kg SKA-31 caused strong sedation in 50% of the animals of either genotypes. KCa3.1(-/- mice were hyperactive (≈+60% in their home cage and SKA-31-administration reduced nocturnal physical activity in KCa3.1(+/+ but not in KCa3.1(-/- mice. CONCLUSIONS/SIGNIFICANCE: KCa3.1-deficiency causes locomotor hyperactivity and altered monoamine levels in selected brain regions, suggesting a so far unknown functional link of KCa3.1 channels to behavior and monoaminergic neurotransmission in mice. The tranquilizing effects of low-dose SKA-31 raise the possibility to use KCa3.1/KCa2 channels as novel pharmacological targets for the treatment of neuropsychiatric hyperactivity disorders.

  19. Altered Carbon Isotope Discrimination of C3 Plants Under Very High pCO2 Levels

    Science.gov (United States)

    Panetta, R. J.; Schubert, B.; Jahren, H.

    2009-12-01

    Various modeling and proxy-based reconstructions of atmospheric pCO2 levels for the last 120 Ma have estimated RCO2 as high as 12x for the Early Cretaceous, generally decreasing into the Cenozoic, and decreasing further into the Quaternary. Multiple ecological studies to assess the effect of elevated CO2 on plant biomass and δ13C value have been spurred on by recent increases in greenhouse gases, however these studies typically grow plants under only slightly elevated CO2 levels (i.e., the twenty foremost studies published since 1990 involved 550 to 750 ppm pCO2, which equals RCO2 = 1.4 to 1.9x). In order to recreate the highest pCO2 environments of the last 120 Ma, we grew radish (Raphanus sativus L.) in growth chambers that maintained controlled environmental conditions and pCO2 levels ranging from ~5 to 11x that of today’s atmosphere (1791 to 4200 ppm); upon harvest we measured total biomass and stable carbon isotope ratio (δ13Cplant) in both above and below ground plant tissue. Unlike the 1:1 relationship between stable isotopes of atmospheric CO2 (δ13Catm) and δ13Cplant observed at lower pCO2 levels (i.e., RCO2 = 1x to 3x; Jahren et al., 2008), the δ13Cplant of biomass grown at more elevated RCO2 was dependent upon δ13Catm according to the linear relationship: δ13Cplant = 1.9(δ13Cplant) - 12.2 ‰ (r2 = 0.71). Concomitantly, we see a highly significant (p sativus L. from -27.0 to -28.0 ‰ at RCO2 = 5x to 11x, respectively. We will discuss possible mechanisms for changing isotope discrimination at very high pCO2 levels that may not be operative at lower concentrations. For example, we noted a striking reduction in the variability of biomass between plants grown at the same (very high) level of pCO2. This variability (calculated as the standard deviation of the log-transformed biomass data after Poorter and Garnier, 1996) decreased by 37 % (above-ground) and 48 % (below-ground) for plants grown at RCO2 > 5x compared to plants grown at RCO2 = 1x to 3x

  20. Higher levels of CO2 during late incubation alter the hatch time of chicken embryos.

    Science.gov (United States)

    Tong, Q; McGonnell, I M; Roulston, N; Bergoug, H; Romanini, C E B; Garain, P; Eterradossi, N; Exadaktylos, V; Bahr, C; Berckmans, D; Demmers, T G M

    2015-01-01

    1. It has been reported that the increasing CO2 tension triggers the embryo to pip the air cell and emerge from the egg. However, the mechanism by which higher CO2 concentrations during the last few days of incubation affect chick physiology and the hatching process is unclear. This study investigated the effect of CO2 concentrations up to 1% during pipping, on the onset and length of the hatch window (HW) and chick quality. 2. Four batches of Ross 308 broiler eggs (600 eggs per batch) were incubated in two small-scale custom-built incubators (Petersime NV). During the final 3 d of incubation, control eggs were exposed to a lower CO2 concentration (0.3%), while the test eggs experienced a higher CO2 concentration programme (peak of 1%). 3. There were no significant differences in blood values, organ weight and body weight. There was also no difference in hatchability between control and test groups. However, a small increase in the chick weight and the percentage of first class chicks was found in the test groups. Furthermore, plasma corticosterone profiles during hatching were altered in embryos exposed to higher CO2; however, they dropped to normal levels at d 21 of incubation. Importantly, the hatching process was delayed and synchronised in the test group, resulting in a narrowed HW which was 2.7 h shorter and 5.3 h later than the control group. 4. These results showed that exposing chicks to 1% CO2 concentration during pipping did not have negative impacts on physiological status of newly hatched chicks. In addition, it may have a significant impact on the physiological mechanisms controlling hatching and have benefits for the health and welfare of chickens by reducing the waiting time after hatching. PMID:25900009

  1. Distribution and ultrastructure of neurons in opossum piriform cortex displaying immunoreactivity to GABA and GAD and high-affinity tritiated GABA uptake

    International Nuclear Information System (INIS)

    GABAergic neurons have been identified in the piriform cortex of the opossum at light and electron microscopic levels by immunocytochemical localization of GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase and by autoradiographic visualization of high-affinity 3H-GABA uptake. Four major neuron populations have been distinguished on the basis of soma size, shape, and segregation at specific depths and locations: large horizontal cells in layer Ia of the anterior piriform cortex, small globular cells with thin dendrites concentrated in layers Ib and II of the posterior piriform cortex, and multipolar and fusiform cells concentrated in the deep part of layer III in anterior and posterior parts of the piriform cortex and the subjacent endopiriform nucleus. All four populations were well visualized with both antisera, but the large layer Ia horizontal cells displayed only very light 3H-GABA uptake, thus suggesting a lack of local axon collaterals or lack of high-affinity GABA uptake sites. The large, ultrastructurally distinctive somata of layer Ia horizontal cells receive a very small number of symmetrical synapses; the thin, axonlike dendrites of small globular cells are exclusively postsynaptic and receive large numbers of both symmetrical and asymmetrical synapses, in contrast to somata which receive a small number of both types; and the deep multipolar and fusiform cells receive a highly variable number of symmetrical and asymmetrical synapses on somata and proximal dendrites. Labeled puncta of axon terminal dimensions were found in large numbers in the neuropil surrounding pyramidal cell somata in layer II and in the endopiriform nucleus. Moderately large numbers of labeled puncta were found in layer I at the depth of pyramidal cell apical dendrites with greater numbers in layer Ia at the depth of distal apical segments than in layer Ib

  2. Distribution and ultrastructure of neurons in opossum piriform cortex displaying immunoreactivity to GABA and GAD and high-affinity tritiated GABA uptake

    Energy Technology Data Exchange (ETDEWEB)

    Haberly, L.B.; Hansen, D.J.; Feig, S.L.; Presto, S.

    1987-12-08

    GABAergic neurons have been identified in the piriform cortex of the opossum at light and electron microscopic levels by immunocytochemical localization of GABA and the GABA-synthesizing enzyme glutamic acid decarboxylase and by autoradiographic visualization of high-affinity /sup 3/H-GABA uptake. Four major neuron populations have been distinguished on the basis of soma size, shape, and segregation at specific depths and locations: large horizontal cells in layer Ia of the anterior piriform cortex, small globular cells with thin dendrites concentrated in layers Ib and II of the posterior piriform cortex, and multipolar and fusiform cells concentrated in the deep part of layer III in anterior and posterior parts of the piriform cortex and the subjacent endopiriform nucleus. All four populations were well visualized with both antisera, but the large layer Ia horizontal cells displayed only very light /sup 3/H-GABA uptake, thus suggesting a lack of local axon collaterals or lack of high-affinity GABA uptake sites. The large, ultrastructurally distinctive somata of layer Ia horizontal cells receive a very small number of symmetrical synapses; the thin, axonlike dendrites of small globular cells are exclusively postsynaptic and receive large numbers of both symmetrical and asymmetrical synapses, in contrast to somata which receive a small number of both types; and the deep multipolar and fusiform cells receive a highly variable number of symmetrical and asymmetrical synapses on somata and proximal dendrites. Labeled puncta of axon terminal dimensions were found in large numbers in the neuropil surrounding pyramidal cell somata in layer II and in the endopiriform nucleus. Moderately large numbers of labeled puncta were found in layer I at the depth of pyramidal cell apical dendrites with greater numbers in layer Ia at the depth of distal apical segments than in layer Ib.

  3. [A pharmaco-ethological study of the GABA-ergic mechanisms regulating the depression-like behavior of mice].

    Science.gov (United States)

    Belozertseva, I V; Andreev, B V

    1997-01-01

    It is known that repeated stress may result in depression-like alterations of behavior. This behavior is characterized by decreased social exploratory activity and increase in occurrence of defensive postures in a social interaction test in mice. The passive defensive behavior is effectively antagonized by antidepressant drugs thus providing a useful animal model of depression. Effects of several GABAergic drugs were studied in opponent test in individually housed male mice. For two weeks preceding the test, mice were repeatedly exposed to foot shock stimulation and/or social confrontation with an aggressive mouse. Muscimol, a selective agonist of GABA(A) receptors, decreased the frequency and duration of defensive postures and increased the duration of some forms of individual activity (grooming and eating), like the agonist of GABA(B) receptors baclofen. Muscimol was the only compound that facilitated exploratory activity towards an unfamiliar partner and did not suppress the locomotion. Effects of another agonist of GABA(B) receptors phenibut and inhibitor of GABA transaminase valproate Na were less specific and consisted in general suppression of behavior (prevalence of static forms of behavior). It can be thought that GABA(A) receptors are essential for regulation of depression-like behavior of mice. PMID:9472168

  4. An atypical residue in the pore of Varroa destructor GABA-activated RDL receptors affects picrotoxin block and thymol modulation.

    Science.gov (United States)

    Price, Kerry L; Lummis, Sarah C R

    2014-12-01

    GABA-activated RDL receptors are the insect equivalent of mammalian GABAA receptors, and play a vital role in neurotransmission and insecticide action. Here we clone the pore lining M2 region of the Varroa mite RDL receptor and show that it has 4 atypical residues when compared to M2 regions of most other insects, including bees, which are the major host of Varroa mites. We create mutant Drosophila RDL receptors containing these substitutions and characterise their effects on function. Using two electrode voltage clamp electrophysiology we show that one substitution (T6'M) ablates picrotoxin inhibition and increases the potency of GABA. This mutation also alters the effect of thymol, which enhances both insect and mammalian GABA responses, and is widely used as a miticide. Thymol decreases the GABA EC50 of WT receptors, enhancing responses, but in T6'M-containing receptors it is inhibitory. The other 3 atypical residues have no major effects on either the GABA EC50, the picrotoxin potency or the effect of thymol. In conclusion we show that the RDL 6' residue is important for channel block, activation and modulation, and understanding its function also has the potential to prove useful in the design of Varroa-specific insecticidal agents. PMID:25460510

  5. Decreased GABA receptor in the cerebral cortex of epileptic rats: effect of Bacopa monnieri and Bacoside-A

    Directory of Open Access Journals (Sweden)

    Mathew Jobin

    2012-02-01

    Full Text Available Abstact Background Gamma amino butyric acid (GABA, the principal inhibitory neurotransmitter in the cerebral cortex, maintains the inhibitory tones that counter balances neuronal excitation. When this balance is perturbed, seizures may ensue. Methods In the present study, alterations of the general GABA, GABAA and GABAB receptors in the cerebral cortex of the epileptic rat and the therapeutic application of Bacopa monnieri were investigated. Results Scatchard analysis of [3H]GABA, [3H]bicuculline and [3H]baclofen in the cerebral cortex of the epileptic rat showed significant decrease in Bmax (P Aά1, GABAAγ, GABAAδ, GABAB and GAD where down regulated (P Aά5 subunit and Cyclic AMP responsible element binding protein were up regulated. Confocal imaging study confirmed the decreased GABA receptors in epileptic rats. Epileptic rats have deficit in radial arm and Y maze performance. Conclusions Bacopa monnieri and Bacoside-A treatment reverses epilepsy associated changes to near control suggesting that decreased GABA receptors in the cerebral cortex have an important role in epileptic occurrence; Bacopa monnieri and Bacoside-A have therapeutic application in epilepsy management.

  6. 塞络通胶囊对大鼠多发性脑梗死恢复期Glu和GABA合成以及NMDA受体亚型表达的影响%Effect of Sailuotong capsule on Glu and GABA levels as well as NMDA receptor subtypes expression in recovery period of rat multiple cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    徐立; 宋文婷; 林成仁; 任建勋; 刘建勋; 姚明江; 王光蕊

    2012-01-01

    The rat model of multi-infarct was adopted in this study to elucidate the protective mechanism of Sailuotong capsule (Sailuotong) in recovery period of multiple cerebral infarction. The effects of Sailuotong on levels of Glu, GABA and the expression of NMDA receptor subtypes including NRI, NR2A and NR2B, were detected. The multi-infarct model rats were established by injecting embolizing microsphere via internal carotid artery, and were given Sailuotong treatment (16.5 and 33.0 mg·kg-1) for 60 days. The pathological changes in brain ultrastructure were observed by transmission electron microscope. The levels of Glu and GABA in brain tissue were measured with high performance liquid chromatography. The expression of NMDA receptors including NRI, NR2A and NR2B in neurons was evaluated by immunohistochemical staining. Compared with the sham rats, abnormal changes were observed in ultrastructures of neurons, neuroglia cells and synapses of model rat brains. Moreover, significant decrease of Glu and GABA, as well as the elevated expression of NRI, NR2A and NR2B were detected in brain tissues. Sailuotong (16.5 and 33.0 mg-kg"1) could improve ultrastructure of cerebral tissue, facilitate synthesis of Glu and GABA, and down-regulate expression of NR1, NR2A and NR2B in neurons. The results demonstrated that Sailuotong could exert neuroprotective effects to some extent in the recovery phase of multiple cerebral infarction by promoting expression of NMDA receptors and synthesis of Glu and GABA.%观察塞络通胶囊(塞络通)对大鼠多发性脑梗死恢复期脑组织中神经递质谷氨酸(Glu)和γ-氨基丁酸(GABA)含量以及NMDA受体亚型NR1、NR2A和NR2B表达的影响,阐述塞络通在脑缺血后恢复期对脑组织保护的作用机制.通过大鼠颈内动脉注射微球血管栓塞剂的方法建立多发性脑梗死大鼠模型,在脑梗死后10天采用不同剂量的寒络通(16.5及33.0 mg·kg 1)连续干预60天.采用透射电子显微镜观察脑

  7. The Glutamine-Glutamate/GABA Cycle

    DEFF Research Database (Denmark)

    Walls, Anne B; Waagepetersen, Helle S; Bak, Lasse Kristoffer;

    2015-01-01

    The operation of a glutamine-glutamate/GABA cycle in the brain consisting of the transfer of glutamine from astrocytes to neurons and neurotransmitter glutamate or GABA from neurons to astrocytes is a well-known concept. In neurons, glutamine is not only used for energy production and protein...... synthesis, as in other cells, but is also an essential precursor for biosynthesis of amino acid neurotransmitters. An excellent tool for the study of glutamine transfer from astrocytes to neurons is [(14)C]acetate or [(13)C]acetate and the glial specific enzyme inhibitors, i.e. the glutamine synthetase...... information about glutamine transfer. The present review will give information about glutamine trafficking and the tools used to map it as exemplified by discussions of published work employing brain cell cultures as well as intact animals. It will be documented that considerably more glutamine is transferred...

  8. The role of vasopressin, somatostatin and GABA in febrile convulsion in rat pups.

    Science.gov (United States)

    Nagaki, S; Nagaki, S; Minatogawa, Y; Sadamatsu, M; Kato, N; Osawa, M; Fukuyama, Y

    1996-01-01

    In order to further elucidate a possible role of neuropeptides and GABA in the pathogenesis of febrile convulsions, we studied changes of immunoreactive-arginine vasopressin (IR-AVP), IR-somatostatin (IR-SRIF) and gamma-aminobutyric acid (GABA) in the rat brain after febrile convulsions induced by ultra-red light (UR). Male Wistar rats at 16 days of age irradiated with UR developed generalized convulsions after 4.9 +/- 0.5 min irradiation. Six rats were killed by microwave irradiation 3 min after UR irradiation prior to convulsion development, and 29 rats were killed either 0 min, 2 h, 6 h, 24 h or 48 h after febrile convulsions. Non-irradiated rats served as controls. The rat brain was dissected into 4 regions; amygdala, hypothalamus, cortex and hippocampus, and subjected to radioimmunoassays. IR-AVP levels in hypothalamus were increased 3 min after UR and decreased at 2 h and 6 h after the convulsions. IR-SRIF levels were increased in cortex and hippocampus at 3 min after UR and 0 min after the convulsions. The GABA content increased in all regions tested at 2 h and 6 h after the convulsions. These results suggest that AVP, SRIF and GABA may be involved in the pathogenesis of febrile convulsions in different ways. PMID:8649210

  9. A novel GABA-mediated corticotropin-releasing hormone secretory mechanism in the median eminence

    Science.gov (United States)

    Kakizawa, Keisuke; Watanabe, Miho; Mutoh, Hiroki; Okawa, Yuta; Yamashita, Miho; Yanagawa, Yuchio; Itoi, Keiichi; Suda, Takafumi; Oki, Yutaka; Fukuda, Atsuo

    2016-01-01

    Corticotropin-releasing hormone (CRH), which is synthesized in the paraventricular nucleus (PVN) of the hypothalamus, plays an important role in the endocrine stress response. The excitability of CRH neurons is regulated by γ-aminobutyric acid (GABA)–containing neurons projecting to the PVN. We investigated the role of GABA in the regulation of CRH release. The release of CRH was impaired, accumulating in the cell bodies of CRH neurons in heterozygous GAD67-GFP (green fluorescent protein) knock-in mice (GAD67+/GFP), which exhibited decreased GABA content. The GABAA receptor (GABAAR) and the Na+-K+-2Cl− cotransporter (NKCC1), but not the K+-Cl− cotransporter (KCC2), were expressed in the terminals of the CRH neurons at the median eminence (ME). In contrast, CRH neuronal somata were enriched with KCC2 but not with NKCC1. Thus, intracellular Cl− concentrations ([Cl−]i) may be increased at the terminals of CRH neurons compared with concentrations in the cell body. Moreover, GABAergic terminals projecting from the arcuate nucleus were present in close proximity to CRH-positive nerve terminals. Furthermore, a GABAAR agonist increased the intracellular calcium (Ca2+) levels in the CRH neuron terminals but decreased the Ca2+ levels in their somata. In addition, the increases in Ca2+ concentrations were prevented by an NKCC1 inhibitor. We propose a novel mechanism by which the excitatory action of GABA maintains a steady-state CRH release from axon terminals in the ME. PMID:27540587

  10. A novel GABA-mediated corticotropin-releasing hormone secretory mechanism in the median eminence.

    Science.gov (United States)

    Kakizawa, Keisuke; Watanabe, Miho; Mutoh, Hiroki; Okawa, Yuta; Yamashita, Miho; Yanagawa, Yuchio; Itoi, Keiichi; Suda, Takafumi; Oki, Yutaka; Fukuda, Atsuo

    2016-08-01

    Corticotropin-releasing hormone (CRH), which is synthesized in the paraventricular nucleus (PVN) of the hypothalamus, plays an important role in the endocrine stress response. The excitability of CRH neurons is regulated by γ-aminobutyric acid (GABA)-containing neurons projecting to the PVN. We investigated the role of GABA in the regulation of CRH release. The release of CRH was impaired, accumulating in the cell bodies of CRH neurons in heterozygous GAD67-GFP (green fluorescent protein) knock-in mice (GAD67(+/GFP)), which exhibited decreased GABA content. The GABAA receptor (GABAAR) and the Na(+)-K(+)-2Cl(-) cotransporter (NKCC1), but not the K(+)-Cl(-) cotransporter (KCC2), were expressed in the terminals of the CRH neurons at the median eminence (ME). In contrast, CRH neuronal somata were enriched with KCC2 but not with NKCC1. Thus, intracellular Cl(-) concentrations ([Cl(-)]i) may be increased at the terminals of CRH neurons compared with concentrations in the cell body. Moreover, GABAergic terminals projecting from the arcuate nucleus were present in close proximity to CRH-positive nerve terminals. Furthermore, a GABAAR agonist increased the intracellular calcium (Ca(2+)) levels in the CRH neuron terminals but decreased the Ca(2+) levels in their somata. In addition, the increases in Ca(2+) concentrations were prevented by an NKCC1 inhibitor. We propose a novel mechanism by which the excitatory action of GABA maintains a steady-state CRH release from axon terminals in the ME. PMID:27540587

  11. What are we measuring with GABA magnetic resonance spectroscopy?

    OpenAIRE

    Stagg, Charlotte J.; Bachtiar, Velicia; Johansen-Berg, Heidi

    2011-01-01

    A number of recent papers1–3 have demonstrated a relationship between in vivo concentration of GABA, as assessed using Magnetic Resonance Spectroscopy (MRS), and an individual's task performance, giving a unique insight into the relationship between physiology and behavior. However, interpretation of the functional significance of the MRS GABA measure is not straightforward. Here we discuss some of the outstanding questions as to how total concentration of GABA within a cortical region relate...

  12. Immunocytochemical Evidence that Monkey Rod Bipolar Cells Use GABA

    OpenAIRE

    Lassová, Luisa; Fina, Marie; Sulaiman, Pyroja; Vard, Noga

    2010-01-01

    Certain bipolar cells in most species immunostain for GABA or its synthesizing enzyme, GAD. However it is unknown whether they actually release GABA, and if so, from which cellular compartment, and by what release mechanism. We investigated these questions in monkey retina where rod bipolar cells immunostain for GABA. We found that rod bipolar cells immunostain for one isoform of GAD, GAD65, in their somas, dendrites, and axon terminals. Near the fovea, the somatic stain of rod bipolar cells ...

  13. Effects of GABA on pancreatic exocrine secretion of rats.

    OpenAIRE

    H. S. Park; Park, H.J.

    2000-01-01

    Since GABA and its related enzymes had been determined in beta-cells of pancreas islets, effects of GABA on pancreatic exocrine secretion were investigated in the isolated perfused rat pancreas. GABA, given intra-arterially at concentrations of 3, 10, 30 and 100 microM, did not exert any influence on spontaneous or secretin (12 pM)-induced pancreatic exocrine secretion. However, GABA further elevated cholecystokinin (10 pM)-, gastrin-releasing peptide (100 pM)- or electrical field stimulation...

  14. Actions of agonists, fipronil and ivermectin on the predominant in vivo splice and edit variant (RDLbd, I/V of the Drosophila GABA receptor expressed in Xenopus laevis oocytes.

    Directory of Open Access Journals (Sweden)

    Kristin Lees

    Full Text Available Ionotropic GABA receptors are the targets for several classes of insecticides. One of the most widely-studied insect GABA receptors is RDL (resistance to dieldrin, originally isolated from Drosophila melanogaster. RDL undergoes alternative splicing and RNA editing, which influence the potency of GABA. Most work has focussed on minority isoforms. Here, we report the first characterisation of the predominant native splice variant and RNA edit, combining functional characterisation with molecular modelling of the agonist-binding region. The relative order of agonist potency is GABA> muscimol> TACA> β-alanine. The I/V edit does not alter the potency of GABA compared to RDLbd. Docking calculations suggest that these agonists bind and activate RDLbdI/V through a similar binding mode. TACA and β-alanine are predicted to bind with lower affinity than GABA, potentially explaining their lower potency, whereas the lower potency of muscimol and isoguvacine cannot be explained structurally from the docking calculations. The A301S (resistance to dieldrin mutation reduced the potency of antagonists picrotoxin, fipronil and pyrafluprole but the I/V edit had no measurable effect. Ivermectin suppressed responses to GABA of RDLbdI/V, RDLbd and RDLbdI/VA301S. The dieldrin resistant variant also showed reduced sensitivity to Ivermectin. This study of a highly abundant insect GABA receptor isoform will help the design of new insecticides.

  15. Actions of agonists, fipronil and ivermectin on the predominant in vivo splice and edit variant (RDLbd, I/V) of the Drosophila GABA receptor expressed in Xenopus laevis oocytes.

    Science.gov (United States)

    Lees, Kristin; Musgaard, Maria; Suwanmanee, Siros; Buckingham, Steven David; Biggin, Philip; Sattelle, David

    2014-01-01

    Ionotropic GABA receptors are the targets for several classes of insecticides. One of the most widely-studied insect GABA receptors is RDL (resistance to dieldrin), originally isolated from Drosophila melanogaster. RDL undergoes alternative splicing and RNA editing, which influence the potency of GABA. Most work has focussed on minority isoforms. Here, we report the first characterisation of the predominant native splice variant and RNA edit, combining functional characterisation with molecular modelling of the agonist-binding region. The relative order of agonist potency is GABA> muscimol> TACA> β-alanine. The I/V edit does not alter the potency of GABA compared to RDLbd. Docking calculations suggest that these agonists bind and activate RDLbdI/V through a similar binding mode. TACA and β-alanine are predicted to bind with lower affinity than GABA, potentially explaining their lower potency, whereas the lower potency of muscimol and isoguvacine cannot be explained structurally from the docking calculations. The A301S (resistance to dieldrin) mutation reduced the potency of antagonists picrotoxin, fipronil and pyrafluprole but the I/V edit had no measurable effect. Ivermectin suppressed responses to GABA of RDLbdI/V, RDLbd and RDLbdI/VA301S. The dieldrin resistant variant also showed reduced sensitivity to Ivermectin. This study of a highly abundant insect GABA receptor isoform will help the design of new insecticides. PMID:24823815

  16. How and why does tomato accumulate a large amount of GABA in the fruit?

    OpenAIRE

    Takayama, Mariko; Ezura, Hiroshi

    2015-01-01

    Gamma-aminobutyric acid (GABA) has received much attention as a health-promoting functional compound, and several GABA-enriched foods have been commercialized. In higher plants, GABA is primarily metabolized via a short pathway called the GABA shunt. The GABA shunt bypasses two steps (the oxidation of α-ketoglutarate to succinate) of the tricarboxylic acid (TCA) cycle via reactions catalyzed by three enzymes: glutamate decarboxylase, GABA transaminase, and succinic semialdehyde dehydrogenase....

  17. Epileptiform activity triggers long-term plasticity of GABA(B) receptor signalling in the developing rat hippocampus.

    OpenAIRE

    Tosetti, Patrizia; Ferrand, Nadine; Colin-Le Brun, Isabelle; Gaïarsa, Jean-Luc

    2005-01-01

    International audience GABA(B) receptor (GABA(B)R)-mediated presynaptic inhibition regulates neurotransmitter release from synaptic terminals. In the neonatal hippocampus, GABA(B)R activation reduces GABA release and terminates spontaneous network discharges called giant depolarizing potentials (GDPs). Blocking GABA(B)Rs transforms GDPs into longer epileptiform discharges. Thus, GABA(B)R-mediated presynaptic inhibition of GABA release (GABA auto-inhibition) controls both spontaneous networ...

  18. GABA representation in hypoxia sensing: a ventilatory study in the rat.

    Science.gov (United States)

    Tarakanov, I; Tikhomirova, L; Tarasova, N; Safonov, V; Bialkowska, M; Pokorski, M

    2011-01-01

    Phenibut, a nonspecific GABA derivative, is clinically used as an anxiolytic and tranquilizer in psychosomatic conditions. A GABA-ergic inhibitory pathway is engaged in respiratory control at both central and peripheral levels. However, the potential of phenibut to affect the O2-related chemoreflexes has not yet been studied. In this study we seek to determine the ventilatory responses to changes in inspired O2 content in anesthetized, spontaneously-breathing rats. Steady-state 5-min responses to 10% O2 in N2 and 100% O2 were taken in each animal before and 1 h after phenibut administration in a dose 450 mg/kg, i.p. Minute ventilation and its frequency and tidal components were obtained from the respiratory flow signal. We found that after a period of irregular extension of the respiratory cycle, phenibut stabilized resting ventilation at a lower level [20.0±3.3 (SD) vs 31.1±5.2 ml/min before phenibut; Pphenibut was not reflected in the hypoxic response. In relative terms, this response was actually accentuated after phenibut; the peak hypoxic ventilation increased by 164% from baseline vs the 100% increase before phenibut. Regarding hyperoxia, its inhibitory effect on breathing was more expressed after phenibut. In conclusion, the GABA-mimetic phenibut did not curtail hypoxic ventilatory responsiveness, despite the presence of GABA-ergic pathways in both central and peripheral, carotid body mechanisms mediating the hypoxic chemoreflex. Thus, GABA-mediated synaptic inhibition may be elaborated in a way to sustain the primarily defensive ventilatory chemoreflex. PMID:21880205

  19. Mitomycin C induced alterations in antioxidant enzyme levels in a model insect species, Spodoptera eridania.

    Science.gov (United States)

    Batcabe, J P; MacGill, R S; Zaman, K; Ahmad, S; Pardini, R S

    1994-05-01

    1. An insect species, the southern armyworm Spodoptera eridania, was used as an in vivo model to examine mitomycin C's (MMC) pro-oxidant effect reflected in alterations of antioxidant enzymes. 2. Following a 2-day exposure to 0.01 and 0.05% w/w dietary concentrations, MMC only induced superoxide dismutase activity. All other enzyme activities were not affected, indicating oxidative stress was mild. 3. Following a 5-day exposure to 0.05% w/w dietary MMC, the activities of superoxide dismutase, glutathione-S-transferase and its peroxidase activity and DT-diaphorase were induced. GR activity was not altered. The high constitutive catalase activity was also not affected. These responses of S. eridania's antioxidant enzymes are analogous to those of mammalian systems in alleviating MMC-induced oxidative stress. 4. S. eridania emerges as an appropriate non-mammalian model for initial and cost-effective screening of drug-induced oxidative stress. PMID:7926607

  20. GABA Coordinates with Insulin in Regulating Secretory Function in Pancreatic INS-1 β-Cells

    OpenAIRE

    Paul Bansal; Shuanglian Wang; Shenghao Liu; Yun-Yan Xiang; Wei-Yang Lu; Qinghua Wang

    2011-01-01

    Pancreatic islet β-cells produce large amounts of γ-aminobutyric acid (GABA), which is co-released with insulin. GABA inhibits glucagon secretion by hyperpolarizing α-cells via type-A GABA receptors (GABA(A)Rs). We and others recently reported that islet β-cells also express GABA(A)Rs and that activation of GABA(A)Rs increases insulin release. Here we investigate the effects of insulin on the GABA-GABA(A)R system in the pancreatic INS-1 cells using perforated-patch recording. The results show...

  1. Genetic and epigenetic alterations induced by different levels of rye genome integration in wheat recipient.

    Science.gov (United States)

    Zheng, X L; Zhou, J P; Zang, L L; Tang, A T; Liu, D Q; Deng, K J; Zhang, Y

    2016-01-01

    The narrow genetic variation present in common wheat (Triticum aestivum) varieties has greatly restricted the improvement of crop yield in modern breeding systems. Alien addition lines have proven to be an effective means to broaden the genetic diversity of common wheat. Wheat-rye addition lines, which are the direct bridge materials for wheat improvement, have been wildly used to produce new wheat cultivars carrying alien rye germplasm. In this study, we investigated the genetic and epigenetic alterations in two sets of wheat-rye disomic addition lines (1R-7R) and the corresponding triticales. We used expressed sequence tag-simple sequence repeat, amplified fragment length polymorphism, and methylation-sensitive amplification polymorphism analyses to analyze the effects of the introduction of alien chromosomes (either the entire genome or sub-genome) to wheat genetic background. We found obvious and diversiform variations in the genomic primary structure, as well as alterations in the extent and pattern of the genomic DNA methylation of the recipient. Meanwhile, these results also showed that introduction of different rye chromosomes could induce different genetic and epigenetic alterations in its recipient, and the genetic background of the parents is an important factor for genomic and epigenetic variation induced by alien chromosome addition. PMID:27323191

  2. GABA receptors modulate trigeminovascular nociceptive neurotransmission in the trigeminocervical complex.

    Science.gov (United States)

    Storer, R J; Akerman, S; Goadsby, P J

    2001-10-01

    1. GABA (gamma-aminobutyric acid) receptors involved in craniovascular nociceptive pathways were characterised by in vivo microiontophoresis of GABA receptor agonists and antagonists onto neurones in the trigeminocervical complex of the cat. 2. Extracellular recordings were made from neurones in the trigeminocervical complex activated by supramaximal electrical stimulation of superior sagittal sinus, which were subsequently stimulated with L-glutamate. 3. Cell firing evoked by microiontophoretic application of L-glutamate (n=30) was reversibly inhibited by GABA in every cell tested (n=19), the GABA(A) agonist muscimol (n=10) in all cells tested, or both where tested, but not by iontophoresis of either sodium or chloride ions at comparable ejection currents. Inhibited cells received wide dynamic range (WDR) or nociceptive specific input from cutaneous receptive fields on the face or forepaws. 4. The inhibition of trigeminal neurones by GABA or muscimol could be antagonized by the GABA(A) antagonist N-methylbicuculline, 1(S),9(R) in all but two cells tested (n=16), but not by the GABA(B) antagonist 2-hydroxysaclofen (n=11). 5. R(-)-baclofen, a GABA(B) agonist, inhibited the firing of three out of seven cells activated by L-glutamate. Where tested, this inhibition could be antagonized by 2-hydroxysaclofen. These baclofen-inhibited cells were characterized as having low threshold mechanoreceptor/WDR input. 6. GABA thus appears to modulate nociceptive input to the trigeminocervical complex mainly through GABA(A) receptors. GABA(A) receptors may therefore provide a target for the development of new therapeutic agents for primary headache disorders. PMID:11606331

  3. GABA (γ-aminobutyric acid) production, antioxidant activity in some germinated dietary seeds and the effect of cooking on their GABA content

    OpenAIRE

    Kasarin TIANSAWANG; Pairoj LUANGPITUKSA; Warunee VARANYANOND; Chanida HANSAWASDI

    2016-01-01

    Abstract Germinated grains have been known as sources of Gamma-aminobutyric acid (GABA) that provide beneficial effects for human health. This study was aimed to investigate GABA production, dietary fiber, antioxidant activity, and the effect of cooking on GABA loss in germinated legumes and sesame. The highest GABA content was found in germinated mung bean, (0.8068 g kg-1, 24 h incubation) followed by germinated soybean, germinated black bean and soaked sesame. Beside GABA, dietary fiber con...

  4. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    OpenAIRE

    Krieger Annette; Thalhammer Andrea; Doepner Richard FG; Geigerseder Christof; Mayerhofer Artur

    2004-01-01

    Abstract The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpoi...

  5. Mutants of GABA transaminase (POP2 suppress the severe phenotype of succinic semialdehyde dehydrogenase (ssadh mutants in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Frank Ludewig

    Full Text Available BACKGROUND: The gamma-aminubutyrate (GABA shunt bypasses two steps of the tricarboxylic acid cycle, and is present in both prokaryotes and eukaryotes. In plants, the pathway is composed of the calcium/calmodulin-regulated cytosolic enzyme glutamate decarboxylase (GAD, the mitochondrial enzymes GABA transaminase (GABA-T; POP2 and succinic semialdehyde dehydrogenase (SSADH. We have previously shown that compromising the function of the GABA-shunt, by disrupting the SSADH gene of Arabidopsis, causes enhanced accumulation of reactive oxygen intermediates (ROIs and cell death in response to light and heat stress. However, to date, genetic investigations of the relationships between enzymes of the GABA shunt have not been reported. PRINCIPAL FINDINGS: To elucidate the role of succinic semialdehyde (SSA, gamma-hydroxybutyrate (GHB and GABA in the accumulation of ROIs, we combined two genetic approaches to suppress the severe phenotype of ssadh mutants. Analysis of double pop2 ssadh mutants revealed that pop2 is epistatic to ssadh. Moreover, we isolated EMS-generated mutants suppressing the phenotype of ssadh revealing two new pop2 alleles. By measuring thermoluminescence at high temperature, the peroxide contents of ssadh and pop2 mutants were evaluated, showing that only ssadh plants accumulate peroxides. In addition, pop2 ssadh seedlings are more sensitive to exogenous SSA or GHB relative to wild type, because GHB and/or SSA accumulate in these plants. SIGNIFICANCE: We conclude that the lack of supply of succinate and NADH to the TCA cycle is not responsible for the oxidative stress and growth retardations of ssadh mutants. Rather, we suggest that the accumulation of SSA, GHB, or both, produced downstream of the GABA-T transamination step, is toxic to the plants, resulting in high ROI levels and impaired development.

  6. Alterations in neuronal calcium levels are associated with cognitive deficits after traumatic brain injury.

    Science.gov (United States)

    Deshpande, Laxmikant S; Sun, David A; Sombati, Sompong; Baranova, Anya; Wilson, Margaret S; Attkisson, Elisa; Hamm, Robert J; DeLorenzo, Robert J

    2008-08-15

    Traumatic brain injury (TBI) survivors often suffer from a post-traumatic syndrome with deficits in learning and memory. Calcium (Ca(2+)) has been implicated in the pathophysiology of TBI-induced neuronal death. However, the role of long-term changes in neuronal Ca(2+) function in surviving neurons and the potential impact on TBI-induced cognitive impairments are less understood. Here we evaluated neuronal death and basal free intracellular Ca(2+) ([Ca(2+)](i)) in acutely isolated rat CA3 hippocampal neurons using the Ca(2+) indicator, Fura-2, at seven and thirty days after moderate central fluid percussion injury. In moderate TBI, cognitive deficits as evaluated by the Morris Water Maze (MWM), occur after injury but resolve after several weeks. Using MWM paradigm we compared alterations in [Ca(2+)](i) and cognitive deficits. Moderate TBI did not cause significant hippocampal neuronal death. However, basal [Ca(2+)](i) was significantly elevated when measured seven days post-TBI. At the same time, these animals exhibited significant cognitive impairment (F(2,25)=3.43, p<0.05). When measured 30 days post-TBI, both basal [Ca(2+)](i) and cognitive functions had returned to normal. Pretreatment with MK-801 blocked this elevation in [Ca(2+)](i) and also prevented MWM deficits. These studies provide evidence for a link between elevated [Ca(2+)](i) and altered cognition. Since no significant neuronal death was observed, the alterations in Ca(2+) homeostasis in the traumatized, but surviving neurons may play a role in the pathophysiology of cognitive deficits that manifest in the acute setting after TBI and represent a novel target for therapeutic intervention following TBI. PMID:18583041

  7. Growth of Streptococcus mutans in Biofilms Alters Peptide Signaling at the Sub-population Level

    Science.gov (United States)

    Shields, Robert C.; Burne, Robert A.

    2016-01-01

    Streptococcus mutans activates multiple cellular processes in response to the formation of a complex between comX-inducing peptide (XIP) and the ComR transcriptional regulator. Bulk phase and microfluidic experiments previously revealed that ComR-dependent activation of comX is altered by pH and by carbohydrate source. Biofilm formation is a major factor in bacterial survival and virulence in the oral cavity. Here, we sought to determine the response of S. mutans biofilm cells to XIP during different stages of biofilm maturation. Using flow cytometry and confocal microscopy, we showed that exogenous addition of XIP to early biofilms resulted in robust comX activation. However, as the biofilms matured, increasing amounts of XIP were required to activate comX expression. Single-cell analysis demonstrated that the entire population was responding to XIP with activation of comX in early biofilms, but only a sub-population was responding in mature biofilms. The sub-population response of mature biofilms was retained when the cells were dispersed and then treated with XIP. The proportion and intensity of the bi-modal response of mature biofilm cells was altered in mutants lacking the Type II toxins MazF and RelE, or in a strain lacking the (p)ppGpp synthase/hydrolase RelA. Thus, competence signaling is markedly altered in cells growing in mature biofilms, and pathways that control cell death and growth/survival decisions modulate activation of comX expression in these sessile populations. PMID:27471495

  8. GABA shunt enzymes and the relationship with morphine abstinence

    NARCIS (Netherlands)

    Th. de Boer (Thijs)

    1977-01-01

    textabstractSelective inhibition of tbe rate-limiting step in tbe degradation of tbe inhibitory neurotransmitter Y·aminobutyric acid (GABA) might be of potential use in the treatment of many neurological or psychiatric disorders since it might correct a central GABA deficiency. Alternatively, as suc

  9. Iontophoretic studies on rat hippocampus with some novel GABA antagonists.

    Science.gov (United States)

    Dalkara, T; Saederup, E; Squires, R F; Krnjevic, K

    1986-08-01

    Twelve substances which appear to be GABA antagonists, judging by their ability to reverse the inhibitory effect of GABA on 35S-TBPS binding to rat brain membranes, were tested iontophoretically on population spikes in the rat hippocampus. Eight of them, including seven which completely reversed the inhibitory action of GABA on 35S-TBPS binding, caused a marked enhancement of population spikes, with slow onset and long duration and they antagonized the inhibition of population spikes by GABA. These effects were similar to those produced by bicuculline. Electrophysiologically, the most potent of the "complete reversers" were bathophenanthroline disulfonate and brucine. In vitro, amoxapine and brucine most effectively reversed the inhibitory action of GABA on 35S-TBPS binding. Of the five substances which only partly reversed the inhibitory effect of GABA on 35S-TBPS binding, four depressed the population spikes and potentiated the inhibitory action of GABA. The fifth "partial reverser", pipazethate, potently increased the population spikes, like the "complete reversers". Although other interpretations are possible the results are consistent with the existence of several GABA-A receptor types in brain, only some of which are blocked by certain partial reversers. PMID:2874465

  10. Acute TSH stimulation in vivo does not alter serum PCSK9 levels

    OpenAIRE

    Gagnon, AnneMarie; Mahzari, Moeber; Lochnan, Heather A; Sorisky, Alexander

    2014-01-01

    Background It is now recognized that TSH can act on targets other than the thyroid, including the liver. Elevated serum TSH levels in euthyroid subjects were recently reported to correlate with high values of serum proprotein convertase subtilisin/kexin type 9 (PCSK9). This protein, expressed and secreted by hepatocytes, promotes higher LDL-cholesterol levels. We tested whether an acute increase of TSH levels following administration of TSH in vivo would raise PCSK9 levels in patients who had...

  11. Ethanol activation of protein kinase A regulates GABA-A receptor subunit expression in the cerebral cortex and contributes to ethanol-induced hypnosis

    Directory of Open Access Journals (Sweden)

    A LeslieMorrow

    2012-04-01

    Full Text Available Protein kinases are implicated in neuronal cell functions such as modulation of ion channel function, trafficking and synaptic excitability. Both protein kinase C (PKC and A (PKA are involved in regulation of γ-aminobutyric acid type A (GABA-A receptors through phosphorylation. However, the role of PKA in regulating GABA-A receptors following acute ethanol exposure is not known. The present study investigated the role of PKA in ethanol effects on GABA-A receptor α1 subunit expression in the P2 synaptosomal fraction of the rat cerebral cortex. Additionally, GABA-related behaviors were also examined. Rats were administered ethanol (2.0 – 3.5 g/kg or saline and PKC, PKA and GABA-A receptor α1 subunit levels were measured by Western blot analysis. Ethanol (3.5 g/kg transiently increased GABA-A receptor α1 subunit expression and PKA RIIβ subunit expression at similar time points whereas PKA RIIα was increased at later time points. In contrast, PKC isoform expression remained unchanged. Notably, the moderate ethanol dose (2.0g/kg had no effect on GABA-A α1 subunit levels although PKA RIIα and RIIβ were increased at 10 and 60 minutes, when PKC isozymes are also known to be elevated. To determine if PKA activation was responsible for the ethanol-induced elevation of GABA-A α1 subunits, the PKA antagonist H89 was administered to rats prior to ethanol exposure. H89 administration prevented ethanol-induced increases in GABA-A receptor α1 subunit expression. Moreover, increasing PKA activity intracerebroventricularly with Sp-cAMP prior to a hypnotic dose of ethanol increased ethanol-induced loss of righting reflex duration. This effect appears to be mediated in part by GABA-A receptors as increasing PKA activity also increased the duration of muscimol-induced loss of righting reflex. Overall these data suggest that PKA mediates ethanol-induced GABA-A receptor expression and contributes to ethanol behavioral effects involving GABA-A receptors.

  12. Alterations in Lipid Levels of Mitochondrial Membranes Induced by Amyloid-ß: A Protective Role of Melatonin

    Directory of Open Access Journals (Sweden)

    Sergio A. Rosales-Corral

    2012-01-01

    Full Text Available Alzheimer pathogenesis involves mitochondrial dysfunction, which is closely related to amyloid-ß (Aß generation, abnormal tau phosphorylation, oxidative stress, and apoptosis. Alterations in membranal components, including cholesterol and fatty acids, their characteristics, disposition, and distribution along the membranes, have been studied as evidence of cell membrane alterations in AD brain. The majority of these studies have been focused on the cytoplasmic membrane; meanwhile the mitochondrial membranes have been less explored. In this work, we studied lipids and mitochondrial membranes in vivo, following intracerebral injection of fibrillar amyloid-ß (Aß. The purpose was to determine how Aß may be responsible for beginning of a vicious cycle where oxidative stress and alterations in cholesterol, lipids and fatty acids, feed back on each other to cause mitochondrial dysfunction. We observed changes in mitochondrial membrane lipids, and fatty acids, following intracerebral injection of fibrillar Aß in aged Wistar rats. Melatonin, a well-known antioxidant and neuroimmunomodulator indoleamine, reversed some of these alterations and protected mitochondrial membranes from obvious damage. Additionally, melatonin increased the levels of linolenic and n-3 eicosapentaenoic acid, in the same site where amyloid ß was injected, favoring an endogenous anti-inflammatory pathway.

  13. GABA uptake inhibitors. Design, molecular pharmacology and therapeutic aspects

    DEFF Research Database (Denmark)

    Krogsgaard-Larsen, P; Frølund, B; Frydenvang, Karla Andrea

    2000-01-01

    In the mid seventies a drug design programme using the Amanita muscaria constituent muscimol (7) as a lead structure, led to the design of guvacine (23) and (R)-nipecotic acid (24) as specific GABA uptake inhibitors and the isomeric compounds isoguvacine (10) and isonipecotic acid (11) as specific...... GABAA receptor agonists. The availability of these compounds made it possible to study the pharmacology of the GABA uptake systems and the GABAA receptors separately. Based on extensive cellular and molecular pharmacological studies using 23, 24, and a number of mono- and bicyclic analogues, it has been...... demonstrated that neuronal and glial GABA transport mechanisms have dissimilar substrate specificities. With GABA transport mechanisms as pharmacological targets, strategies for pharmacological interventions with the purpose of stimulating GABA neurotransmission seem to be (1) effective blockade of neuronal as...

  14. Conditions that alter intracellular cAMP levels affect expression of the cAMP phosphodiesterase gene in Dictyostelium.

    OpenAIRE

    Riley, B B; Barclay, S L

    1990-01-01

    We examined expression of the Dictyostelium cAMP phosphodiesterase (PDE) gene under conditions that alter intracellular cAMP levels during in vitro differentiation of wild-type strain V12M2 and a sporogenous derivative, HB200. In control cultures, cellular PDE activity peaked at 6 hr and declined by 8 hr, while secreted PDE activity continued to increase through 8 hr. Lowering intracellular cAMP levels with caffeine or progesterone increased cellular and secreted PDE activities 2-fold, increa...

  15. Attenuation of cocaine-seeking by GABAB receptor agonists baclofen and CGP44532 but not the GABA reuptake inhibitor tiagabine in baboons

    OpenAIRE

    Weerts, Elise M.; Froestl, Wolfgang; Kaminski, Barbara J.; Griffiths, Roland R.

    2007-01-01

    The current study evaluated the effects of drugs that increase GABA levels by activation of GABAB receptors (baclofen and CGP44532) or by inhibition of GABA reuptake (tiagabine) on the reinstatement of extinguished lever responding produced by priming doses of cocaine in baboons (i.e., cocaine-seeking). Cocaine self-injection was established and maintained under a fixed ratio (FR10) schedule of reinforcement during daily 2-h sessions. Lever responding was extinguished by substituting vehicle ...

  16. The effects of agonists of ionotropic GABA(A) and metabotropic GABA(B) receptors on learning.

    Science.gov (United States)

    Zyablitseva, Evgeniya A; Kositsyn, Nikolay S; Shul'gina, Galina I

    2009-05-01

    The research described here investigates the role played by inhibitory processes in the discriminations made by the nervous system of humans and animals between familiar and unfamiliar and significant and nonsignificant events. This research compared the effects of two inhibitory mediators of gamma-aminobutyric acid (GABA): 1) phenibut, a nonselective agonist of ionotropic GABA(A) and metabotropic GABA(B) receptors and 2) gaboxadol a selective agonist of ionotropic GABA(A) receptors on the process of developing active defensive and inhibitory conditioned reflexes in alert non-immobilized rabbits. It was found that phenibut, but not gaboxadol, accelerates the development of defensive reflexes at an early stage of conditioning. Both phenibut and gaboxadol facilitate the development of conditioned inhibition, but the effect of gaboxadol occurs at later stages of conditioning and is less stable than that of phenibut. The earlier and more stable effects of phenibut, as compared to gaboxadol, on storage in memory of the inhibitory significance of a stimulus may occur because GABA(B) receptors play the dominant role in the development of internal inhibition during an early stage of conditioning. On the other hand this may occur because the participation of both GABA(A) and GABA(B) receptors are essential to the process. We discuss the polyfunctionality of GABA receptors as a function of their structure and the positions of the relevant neurons in the brain as this factor can affect regulation of various types of psychological processes. PMID:19476215

  17. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    OpenAIRE

    K.S. Canuto; L.P.S. Sergio; O.R. Guimarães; Geller, M.; De Paoli, F; Fonseca, A.S.

    2015-01-01

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiati...

  18. No alteration in serum leptin levels during acute endotoxemia in sheep.

    Science.gov (United States)

    Soliman, M; Abdelhady, S; Fattouh, I; Ishioka, K; Kitamura, H; Kimura, K; Saito, M

    2001-10-01

    To determine the role of leptin in endotoxin-induced anorexia in ruminants, circulating leptin levels were measured during acute experimental endotoxemia in sheep. Injection of bacterial lipopolysaccharide (450 ng/kg, i.v.) induced anorexia accompanied with fever and increases in serum levels of cortisol, insulin and glucose which are known to stimulate leptin secretion in rodent and human, while it did not affect serum leptin levels at all. These results indicate that serum leptin levels in sheep during acute endotoxemia are differentially regulated from those in rodent and human, and that leptin might not be involved in the endotoxin-induced anorexia in sheep. PMID:11714034

  19. Proteolysis and bioconversion of cereal proteins to glutamate and γ-Aminobutyrate (GABA) in Rye malt sourdoughs.

    Science.gov (United States)

    Stromeck, Achim; Hu, Ying; Chen, Lingyun; Gänzle, Michael G

    2011-02-23

    This study aimed to achieve the conversion of cereal proteins to the alternative end products glutamate or γ-aminobutyrate (GABA). Rye malt, fungal proteases, and lactobacilli were employed to convert wheat gluten or barley proteins. Glutamate and GABA formations were strain-dependent. Lactobacillus reuteri TMW1.106 and Lactobacillus rossiae 34J accumulated glutamate; L. reuteri LTH5448 and LTH5795 accumulated GABA. Glutamate and GABA accumulation by L. reuteri TMW1.106 and LTH5448 increased throughout fermentation time over 96 h, respectively. Peptides rather than amino acids were the main products of proteolysis in all doughs, and barley proteins were more resistant to degradation by rye malt proteases than wheat gluten. However, addition of fungal protease resulted in comparable degradation of both substrates. Glutamate and GABA accumulated to concentrations up to 63 and 90 mmol kg(-1) DM, respectively. Glutamate levels obtained through bioconversion of cereal proteins enable the use of hydrolyzed cereal protein as condiment. PMID:21271723

  20. Long-term variation in above and belowground plant inputs alters soil organic matter biogeochemistry at the molecular-level

    Science.gov (United States)

    Simpson, M. J.; Pisani, O.; Lin, L.; Lun, O.; Simpson, A.; Lajtha, K.; Nadelhoffer, K. J.

    2015-12-01

    The long-term fate of soil carbon reserves with global environmental change remains uncertain. Shifts in moisture, altered nutrient cycles, species composition, or rising temperatures may alter the proportions of above and belowground biomass entering soil. However, it is unclear how long-term changes in plant inputs may alter the composition of soil organic matter (SOM) and soil carbon storage. Advanced molecular techniques were used to assess SOM composition in mineral soil horizons (0-10 cm) after 20 years of Detrital Input and Removal Treatment (DIRT) at the Harvard Forest. SOM biomarkers (solvent extraction, base hydrolysis and cupric (II) oxide oxidation) and both solid-state and solution-state nuclear magnetic resonance (NMR) spectroscopy were used to identify changes in SOM composition and stage of degradation. Microbial activity and community composition were assessed using phospholipid fatty acid (PLFA) analysis. Doubling aboveground litter inputs decreased soil carbon content, increased the degradation of labile SOM and enhanced the sequestration of aliphatic compounds in soil. The exclusion of belowground inputs (No roots and No inputs) resulted in a decrease in root-derived components and enhanced the degradation of leaf-derived aliphatic structures (cutin). Cutin-derived SOM has been hypothesized to be recalcitrant but our results show that even this complex biopolymer is susceptible to degradation when inputs entering soil are altered. The PLFA data indicate that changes in soil microbial community structure favored the accelerated processing of specific SOM components with littler manipulation. These results collectively reveal that the quantity and quality of plant litter inputs alters the molecular-level composition of SOM and in some cases, enhances the degradation of recalcitrant SOM. Our study also suggests that increased litterfall is unlikely to enhance soil carbon storage over the long-term in temperate forests.

  1. Acute net stressor increases whole-body cortisol levels without altering whole-brain monoamines in zebrafish.

    Science.gov (United States)

    Tran, Steven; Chatterjee, Diptendu; Gerlai, Robert

    2014-10-01

    Recent studies have started to examine the neurochemical and hormonal basis of behavior in zebrafish by examining biological correlates postmortem. However, it is unknown whether stress involved with experimental handling prior to euthanizing animals will have an impact on subsequent biological measures. In the current study, we expose zebrafish to a short net handling stressor (30 s) and examine the levels of monoamine neurotransmitters (dopamine, serotonin, and their metabolites) and whole-body cortisol at different intervals poststressor (0, 1, 5, 10, and 15 min). We report a time-dependent increase in the levels of cortisol, but no alterations in the levels of dopamine, DOPAC (dopamine's metabolite), serotonin, or 5HIAA (serotonin's metabolite) poststressor. The results demonstrate cortisol levels are more responsive to this type of stimulus compared with neurochemical measures. PMID:24911317

  2. Alteration of reproductive steroids of male winter flounder (Pleuronectes americanus) chronically exposed to low levels of crude oil in sediments

    International Nuclear Information System (INIS)

    When male winter flounder (Pleuronectes americanus) were held in seawater for 4 months exposed to sand treated with five low levels of crude oil, there was a significant reduction in testosterone and 11-ketotestosterone glucuronides in blood plasma. At the two higher levels of oil the concentration of plasma glucuronides were similar but very significantly lower than the controls or the three lower concentrations of oil. For both androgens the ratio of glucuronides to free steroids declined in a stepwise fashion. Free testosterone and 11-ketotestosterone plasma levels were not significantly affected by any concentration of oil in the sediment. Liver weights as a percentage of body weight were significantly increased at the two highest levels of oil in sediments, but neither body weights nor testes weights were altered by exposure to oil. It has been suggested that androgen glucuronides can function as pheromones in some fish and this is one potentially deleterious effect of exposure to oil. 33 refs., 1 tab

  3. GABA agonist promoted formation of low affinity GABA receptors on cerebellar granule cells is restricted to early development

    DEFF Research Database (Denmark)

    Belhage, B; Hansen, Gert Helge; Schousboe, A;

    1988-01-01

    The ability of the GABA receptor agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP) to promote formation of low affinity GABA receptors on cerebellar granule cells was tested using primary cultures of these neurons. Granule cells were exposed to THIP (150 microM) for 6 hr after......, respectively, 4, 7, 10 and 14 days in culture. It was found that THIP treatment of 4- and 7-day-old cultures led to formation of low affinity GABA receptors, whereas such receptors could not be detected after THIP treatment in the older cultures (10 and 14 days) in spite of the fact that these cultured granule...... cells expressed a high density of high affinity GABA receptors. It is concluded that the ability of THIP to promote formation of low affinity GABA receptors on cerebellar granule cells is restricted to an early developmental period....

  4. Alterations of serum levels of BDNF-related miRNAs in patients with depression.

    Directory of Open Access Journals (Sweden)

    You-Jie Li

    Full Text Available Depression is a serious and potentially life-threatening mental disorder with unknown etiology. Emerging evidence shows that brain-derived neurotrophic factor (BDNF and microRNAs (miRNAs play critical roles in the etiology of depression. Here this study was aimed to identify and characterize the roles of BDNF and its putative regulatory miRNAs in depression. First, we identified that miR-182 may be a putative miRNA that regulates BDNF levels by bioinformatic studies, and characterized the effects of miR-182 on the BDNF levels using cell-based studies, side by side with miR-132 (a known miRNA that regulates BDNF expression. We showed that treatment of miR-132 and miR-182 respectively decreased the BDNF protein levels in a human neuronal cell model, supporting the regulatory roles of miR-132 and miR-182 on the BDNF expression. Furthermore, we explored the roles of miR-132 and miR-182 on the BDNF levels in depression using human subjects by assessing their serum levels. Compared with the healthy controls, patients with depression showed lower serum BDNF levels (via the enzyme-linked immunosorbent assays and higher serum miR-132 and miR-182 levels (via the real-time PCR. Finally, the Pearson's (or Spearman's correlation coefficient was calculated to study whether there was a relationship among the Self-Rating Depression Scale score, the serum BDNF levels, and serum BDNF-related miRNA levels. Our results revealed that there was a significant negative correlation between the SDS scores and the serum BDNF levels, and a positive correlation between the SDS scores and miR-132 levels. In addition, we found a reverse relationship between the serum BDNF levels and the miR-132/miR-182 levels in depression. Collectively, we provided evidence supporting that miR-182 is a putative BDNF-regulatory miRNA, and suggested that the serum BDNF and its related miRNAs may be utilized as important biomarkers in the diagnosis or as therapeutic targets of depression.

  5. GABA-agonists induce the formation of low-affinity GABA-receptors on cultured cerebellar granule cells via preexisting high affinity GABA receptors

    DEFF Research Database (Denmark)

    Belhage, B; Meier, E; Schousboe, A

    1986-01-01

    The kinetics of specific GABA-binding to membranes isolated from cerebellar granule cells, cultured for 12 days from dissociated cerebella of 7-day-old rats was studied using [3H]GABA as the ligand. The granule cells were cultured in the presence of the specific GABA receptor agonist 4, 5, 6, 7......-tetrahydroisoxazolo [5,4-c]pyridin-3-ol (THIP, 150 microM) or THIP plus the antagonist bicuculline methobromide (150 microM of each) or in the absence of the agonist or antagonist. Membranes isolated from granule cells cultured in a medium without the GABA agonist revealed a single binding site for GABA with a...... binding constant (KD) of 7.9 +/- 0.4 nM and a Bmax of 3.42 +/- 0.08 pmol X mg-1 protein. Membranes from cells cultured in the presence of THIP had two binding sites for GABA with KD-values of 6.8 +/- 0.9 nM and 476 +/- 311 nM, respectively. The corresponding Bmax values were 4.41 +/- 0.42 pmol X mg-1 and...

  6. Plasma homocysteine levels are independently associated with alterations of large artery stiffness in men but not in women

    Institute of Scientific and Technical Information of China (English)

    Li SHENG; Cai WU; Yong-Yi BAI; Wen-Kai XIAO; Dan FENG; Ping YE

    2015-01-01

    Objectives To investigate the associations of the plasma homocysteine levels with the alterations in arterial stiffness in a commu-nity-based cohort. The gender differences in these associations were examined. Methods We evaluated the relationship between plasma homocysteine levels to three measures of vascular function [carotid-femoral pulse wave velocity (CF-PWV), carotid-ankle PWV (CA-PWV) and heart rate corrected augmentation index (AI)] in 1680 participants (mean age:61.5 years;709 men, 971 women) from communities of Beijing, China. Results In univariate analysis, plasma homocysteine levels was positively related to the CF-PWV (r=0.211, P<0.0001) and CA-PWV (r=0.148, P<0.0001), whereas inversely associated with AI (r=−0.052, P=0.016). In multiple linear regression models adjusting for covariants, plasma homocysteine remained positively related to the CF-PWV (standardizedβ=0.065, P=0.007) in total cases. When the groups of men and women were examined separately, plasma homocysteine remained positively associated with the CF-PWV (standardizedβ=0.082, P=0.023) in men, whereas the relations between homocysteine and any of the arterial stiffness indices were not further present in women. Conclusions In Chinese population, plasma homocysteine levels are independently associated with alterations of large artery stiffness in men but not in women.

  7. [GABA-NO interaction in the N. Accumbens during danger-induced inhibition of exploratory behavior].

    Science.gov (United States)

    2013-01-01

    In Sprague-Dawley rats by means of in vivo microdialysis combined with HPLC analysis, it was shown that presentation to rats during exploratory activity of a tone previously pared with footshock inhibited the exploration and prevented the exploration-induced increase in extracellular levels of citrulline (an NO co-product) in the medial n. accumbens. Intra-accumbal infusions of 20 μM bicuculline, a GABA(A)-receptor antagonist, firstly, partially restored the exploration-induced increase of extracellular citrulline levels in this brain area, which was inhibited by presentation of the tone, previously paired with foot-shock and, secondly, prevented the inhibition of exploratory behavior produced by this sound signal of danger. The data obtained indicate for the first time that signals of danger inhibit exploratory behavior and exploration-induced activation of the accumbal nitrergic system via GABA(A)-receptor mechanisms. PMID:25508395

  8. Hippocampal GABA transporter distribution in patients with temporal lobe epilepsy and hippocampal sclerosis

    NARCIS (Netherlands)

    Schijns, O.; Karaca, U.; Andrade, P.; Nijs, L. de; Kusters, B.; Peeters, A.; Dings, J.; Pannek, H.; Ebner, A.; Rijkers, K.; Hoogland, G.

    2015-01-01

    PURPOSE: To determine hippocampal expression of neuronal GABA-transporter (GAT-1) and glial GABA-transporter (GAT-3) in patients with temporal lobe epilepsy (TLE) and hippocampal sclerosis (HS). METHODS: Hippocampal sections were immunohistochemically stained for GABA-transporter 1 and GABA-transpor

  9. Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels.

    Directory of Open Access Journals (Sweden)

    Xian-E Peng

    Full Text Available Liver fatty acid-binding protein (L-FABP, also known as fatty acid-binding protein 1 (FABP1, is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182 from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032.Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05. The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01. In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003, while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014. Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans.

  10. Association of a Human FABP1 Gene Promoter Region Polymorphism with Altered Serum Triglyceride Levels.

    Science.gov (United States)

    Peng, Xian-E; Wu, Yun-Li; Zhu, Yi-Bing; Huang, Rong-Dong; Lu, Qing-Qing; Lin, Xu

    2015-01-01

    Liver fatty acid-binding protein (L-FABP), also known as fatty acid-binding protein 1 (FABP1), is a key regulator of hepatic lipid metabolism. Elevated FABP1 levels are associated with an increased risk of cardiovascular disease (CVD) and metabolic syndromes. In this study, we examine the association of FABP1 gene promoter variants with serum FABP1 and lipid levels in a Chinese population. Four promoter single-nucleotide polymorphisms (SNPs) of FABP1 gene were genotyped in a cross-sectional survey of healthy volunteers (n = 1,182) from Fuzhou city of China. Results showed that only the rs2919872 G>A variant was significantly associated with serum TG concentration(P = 0.032).Compared with the rs2919872 G allele, rs2919872 A allele contributed significantly to reduced serum TG concentration, and this allele dramatically decreased the FABP1 promoter activity(P < 0.05). The rs2919872 A allele carriers had considerably lower serum FABP1 levels than G allele carriers (P < 0.01). In the multivariable linear regression analysis, the rs2919872 A allele was negatively associated with serum FABP1 levels (β = -0.320, P = 0.003), while serum TG levels were positively associated with serum FABP1 levels (β = 0.487, P = 0.014). Our data suggest that compared with the rs2919872 G allele, the rs2919872 A allele reduces the transcriptional activity of FABP1 promoter, and thereby may link FABP1 gene variation to TG level in humans. PMID:26439934

  11. Pregnenolone sulfate restores the glutamate-nitric-oxide-cGMP pathway and extracellular GABA in cerebellum and learning and motor coordination in hyperammonemic rats.

    Science.gov (United States)

    Gonzalez-Usano, Alba; Cauli, Omar; Agusti, Ana; Felipo, Vicente

    2014-02-19

    Around 40% of cirrhotic patients show minimal hepatic encephalopathy (MHE), with mild cognitive impairment which reduces their quality of life and life span. Treatment of MHE is unsatisfactory, and there are no specific treatments for the neurological alterations in MHE. Hyperammonemia is the main contributor to neurological alterations in MHE. New agents acting on molecular targets involved in brain mechanisms leading to neurological alterations are needed to treat MHE. Chronic hyperammonemia impairs learning of a Y-maze task by impairing the glutamate-nitric-oxide (NO)-cGMP pathway in cerebellum, in part by enhancing GABA(A) receptor activation, which also induces motor in-coordination. Acute pregnenolone sulfate (PregS) restores the glutamate-NO-cGMP pathway in hyperammonemic rats. This work aimed to assess whether chronic treatment of hyperammonemic rats with PregS restores (1) motor coordination; (2) extracellular GABA in cerebellum; (3) learning of the Y-maze task; (4) the glutamate-NO-cGMP pathway in cerebellum. Chronic intracerebral administration of PregS normalizes motor coordination likely due to extracellular GABA reduction. PregS restores learning ability by restoring the glutamate-NO-cGMP pathway, likely due to both enhanced NMDA receptor activation and reduced GABA(A) receptor activation. Similar treatments would improve cognitive and motor alterations in patients with MHE. PMID:24256194

  12. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    Directory of Open Access Journals (Sweden)

    K.S. Canuto

    2015-01-01

    Full Text Available Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC. Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out.

  13. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    International Nuclear Information System (INIS)

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

  14. CrBPF1 overexpression alters transcript levels of terpenoid indole alkaloid biosynthetic and regulatory genes.

    Science.gov (United States)

    Li, Chun Yao; Leopold, Alex L; Sander, Guy W; Shanks, Jacqueline V; Zhao, Le; Gibson, Susan I

    2015-01-01

    Terpenoid indole alkaloid (TIA) biosynthesis in Catharanthus roseus is a complex and highly regulated process. Understanding the biochemistry and regulation of the TIA pathway is of particular interest as it may allow the engineering of plants to accumulate higher levels of pharmaceutically important alkaloids. Toward this end, we generated a transgenic C. roseus hairy root line that overexpresses the CrBPF1 transcriptional activator under the control of a β-estradiol inducible promoter. CrBPF1 is a MYB-like protein that was previously postulated to help regulate the expression of the TIA biosynthetic gene STR. However, the role of CrBPF1 in regulation of the TIA and related pathways had not been previously characterized. In this study, transcriptional profiling revealed that overexpression of CrBPF1 results in increased transcript levels for genes from both the indole and terpenoid biosynthetic pathways that provide precursors for TIA biosynthesis, as well as for genes in the TIA biosynthetic pathway. In addition, overexpression of CrBPF1 causes increases in the transcript levels for 11 out of 13 genes postulated to act as transcriptional regulators of genes from the TIA and TIA feeder pathways. Interestingly, overexpression of CrBPF1 causes increased transcript levels for both TIA transcriptional activators and repressors. Despite the fact that CrBPF1 overexpression affects transcript levels of a large percentage of TIA biosynthetic and regulatory genes, CrBPF1 overexpression has only very modest effects on the levels of the TIA metabolites analyzed. This finding may be due, at least in part, to the up-regulation of both transcriptional activators and repressors in response to CrBPF1 overexpression, suggesting that CrBPF1 may serve as a "fine-tune" regulator for TIA biosynthesis, acting to help regulate the timing and amplitude of TIA gene expression. PMID:26483828

  15. CrBPF1 overexpression alters transcript levels of terpenoid indole alkaloid biosynthetic and regulatory genes

    Directory of Open Access Journals (Sweden)

    Chun Yao eLi

    2015-10-01

    Full Text Available Terpenoid indole alkaloid (TIA biosynthesis in Catharanthus roseus is a complex and highly regulated process. Understanding the biochemistry and regulation of the TIA pathway is of particular interest as it may allow the engineering of plants to accumulate higher levels of pharmaceutically important alkaloids. Towards this end, we generated a transgenic C. roseus hairy root line that overexpresses the CrBPF1 transcriptional activator under the control of a β-estradiol inducible promoter. CrBPF1 is a MYB-like protein that was previously postulated to help regulate the expression of the TIA biosynthetic gene STR. However, the role of CrBPF1 in regulation of the TIA and related pathways had not been previously characterized. In this study, transcriptional profiling revealed that overexpression of CrBPF1 results in increased transcript levels for genes from both the indole and terpenoid biosynthetic pathways that provide precursors for TIA biosynthesis, as well as for genes in the TIA biosynthetic pathway. In addition, overexpression of CrBPF1 causes increases in the transcript levels for 11 out of 13 genes postulated to act as transcriptional regulators of genes from the TIA and TIA feeder pathways. Interestingly, overexpression of CrBPF1 causes increased transcript levels for both TIA transcriptional activators and repressors. Despite the fact that CrBPF1 overexpression affects transcript levels of a large percentage of TIA biosynthetic and regulatory genes, CrBPF1 overexpression has only very modest effects on the levels of the TIA metabolites analyzed. This finding may be due, at least in part, to the up-regulation of both transcriptional activators and repressors in response to CrBPF1 overexpression, suggesting that CrBPF1 may serve as a fine-tune regulator for TIA biosynthesis, acting to help regulate the timing and amplitude of TIA gene expression.

  16. Low-level red laser therapy alters effects of ultraviolet C radiation on Escherichia coli cells

    Energy Technology Data Exchange (ETDEWEB)

    Canuto, K.S.; Guimaraes, O.R.; Geller, M. [Centro Universitario Serra dos Orgaos, Teresopolis, RJ (Brazil). Centro de Ciencias da Saude; Sergio, L.P.S. [Instituto de Biologia Roberto Alcantara Gomes, Rio de Janeiro, RJ (Brazil). Departamento de Biofisica e Biometria; Paoli, F. [Universidade Federal de Juiz de Fora (UFJF), Juiz de Fora, MG (Brazil). Departamento de Morfologia; Fonseca, A.S., E-mail: adnfonseca@ig.com.br [Universidade Federal do Estado do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil). Departamento de Ciencias Fisiologicas

    2015-10-15

    Low-level lasers are used at low power densities and doses according to clinical protocols supplied with laser devices or based on professional practice. Although use of these lasers is increasing in many countries, the molecular mechanisms involved in effects of low-level lasers, mainly on DNA, are controversial. In this study, we evaluated the effects of low-level red lasers on survival, filamentation, and morphology of Escherichia coli cells that were exposed to ultraviolet C (UVC) radiation. Exponential and stationary wild-type and uvrA-deficient E. coli cells were exposed to a low-level red laser and in sequence to UVC radiation. Bacterial survival was evaluated to determine the laser protection factor (ratio between the number of viable cells after exposure to the red laser and UVC and the number of viable cells after exposure to UVC). Bacterial filaments were counted to obtain the percentage of filamentation. Area-perimeter ratios were calculated for evaluation of cellular morphology. Experiments were carried out in duplicate and the results are reported as the means of three independent assays. Pre-exposure to a red laser protected wild-type and uvrA-deficient E. coli cells against the lethal effect of UVC radiation, and increased the percentage of filamentation and the area-perimeter ratio, depending on UVC fluence and physiological conditions in the cells. Therapeutic, low-level red laser radiation can induce DNA lesions at a sub-lethal level. Consequences to cells and tissues should be considered when clinical protocols based on this laser are carried out. (author)

  17. GABA(B), not GABA(A) receptors play a role in cortical postictal refractoriness

    Czech Academy of Sciences Publication Activity Database

    Mareš, Pavel; Kubová, Hana

    2015-01-01

    Roč. 88, Jan 2015 (2015), s. 99-102. ISSN 0028-3908 R&D Projects: GA MŠk(CZ) LH11015; GA ČR(CZ) GAP302/10/0971; GA ČR(CZ) GBP304/12/G069 Institutional support: RVO:67985823 Keywords : cortical seizures * postictal refractoriness * GABA receptors * pharmacology Subject RIV: FH - Neurology Impact factor: 5.106, year: 2014

  18. Reduced parahippocampal and lateral temporal GABA{sub A}-[{sup 11}C]flumazenil binding in major depression: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Klumpers, Ursula M.H. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); GGZ inGeest, partner of VUmc, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Veltman, Dick J. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Drent, Madeleine L. [VU University Medical Center, Department of Endocrinology, Amsterdam (Netherlands); Boellaard, Ronald; Lammertsma, Adriaan A. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Comans, Emile F.I. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Meynen, Gerben [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); Hoogendijk, Witte J.G. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Center for Neurogenomics and Cognitive Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands)

    2010-03-15

    Major depressive disorder (MDD) has been related to both a dysfunctional {gamma}-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABA{sub A}-benzodiazepine receptor in depressed patients or in relation to antidepressant treatment. Eleven depressed outpatients were compared, before and after treatment with citalopram, with nine age-matched healthy controls. The subjects were scanned using the positron emission tomography (PET) tracer [{sup 11}C]flumazenil ([{sup 11}C]FMZ). Parametric voxel-by-voxel Logan plots were compared with methods based on regions of interest (ROI), to provide volume of distribution (V{sub T}) and binding potential (BP{sub ND}) values. Plasma GABA levels were determined and a dexamethasone-corticotropin releasing hormone (DEX-CRH) test was performed. In MDD, parametric voxel-by-voxel Logan plots showed bilateral reduced [{sup 11}C]FMZ binding in the parahippocampal gyrus and right lateral superior temporal gyrus (p uncorrected {<=}0.001). In the temporal area, [{sup 11}C]FMZ binding showed a strong inverse correlation with HPA axis activity. Plasma GABA did not discriminate MDD from controls, but correlated inversely with [{sup 11}C]FMZ binding in the right insula. Following treatment with citalopram, voxel-based analysis revealed reduced binding in the right lateral temporal gyrus and dorsolateral prefrontal cortex. The bilateral reduction in limbic parahippocampal and right temporal [{sup 11}C]FMZ binding found in MDD indicates decreased GABA{sub A}-benzodiazepine receptor complex affinity and/or number. The inverse relationship between GABA{sub A} binding in the temporal lobe and HPA axis activity, suggests that HPA axis hyperactivity is partly due to reduced GABA-ergic inhibition. (orig.)

  19. An Electrostatic Funnel in the GABA-Binding Pathway

    Science.gov (United States)

    Lightstone, Felice C.

    2016-01-01

    The γ-aminobutyric acid type A receptor (GABAA-R) is a major inhibitory neuroreceptor that is activated by the binding of GABA. The structure of the GABAA-R is well characterized, and many of the binding site residues have been identified. However, most of these residues are obscured behind the C-loop that acts as a cover to the binding site. Thus, the mechanism by which the GABA molecule recognizes the binding site, and the pathway it takes to enter the binding site are both unclear. Through the completion and detailed analysis of 100 short, unbiased, independent molecular dynamics simulations, we have investigated this phenomenon of GABA entering the binding site. In each system, GABA was placed quasi-randomly near the binding site of a GABAA-R homology model, and atomistic simulations were carried out to observe the behavior of the GABA molecules. GABA fully entered the binding site in 19 of the 100 simulations. The pathway taken by these molecules was consistent and non-random; the GABA molecules approach the binding site from below, before passing up behind the C-loop and into the binding site. This binding pathway is driven by long-range electrostatic interactions, whereby the electrostatic field acts as a ‘funnel’ that sweeps the GABA molecules towards the binding site, at which point more specific atomic interactions take over. These findings define a nuanced mechanism whereby the GABAA-R uses the general zwitterionic features of the GABA molecule to identify a potential ligand some 2 nm away from the binding site. PMID:27119953

  20. A Gut Feeling about GABA: Focus on GABAB receptors

    Directory of Open Access Journals (Sweden)

    Niall P Hyland

    2010-10-01

    Full Text Available Gamma-Aminobutyric acid (GABA is the main inhibitory neurotransmitter in the body and hence GABA-mediated neurotransmission regulates many physiological functions, including those in the gastrointestinal (GI tract. GABA is located throughout the GI tract and is found in enteric nerves as well as in endocrine-like cells, implicating GABA as both a neurotransmitter and an endocrine mediator influencing GI function. GABA mediates its effects via GABA receptors which are either ionotropic GABAA or metabotropic GABAB. The latter which respond to the agonist baclofen have been least characterised, however accumulating data suggest that they play a key role in GI function in health and disease. Like GABA, GABAB receptors have been detected throughout the gut of several species in the enteric nervous system, muscle and epithelial layers as well as on endocrine-like cells. Such widespread distribution of this metabotropic GABA receptor is consistent with its significant modulatory role over intestinal motility, gastric emptying and acid secretion, transient lower esophageal sphincter relaxation and visceral sensation of painful colonic stimuli. More intriguing findings, the mechanisms underlying which have yet to be determined, suggest GABAB receptors inhibit GI carcinogenesis and tumour growth. Therefore, the diversity of GI functions regulated by GABAB receptors makes it a potentially useful target in the treatment of several GI disorders. In light of the development of novel compounds such as peripherally acting GABAB receptor agonists, positive allosteric modulators of the GABAB receptor and GABA producing enteric bacteria, we review and summarize current knowledge on the function of GABAB receptors within the GI tract.

  1. An Electrostatic Funnel in the GABA-Binding Pathway.

    Directory of Open Access Journals (Sweden)

    Timothy S Carpenter

    2016-04-01

    Full Text Available The γ-aminobutyric acid type A receptor (GABAA-R is a major inhibitory neuroreceptor that is activated by the binding of GABA. The structure of the GABAA-R is well characterized, and many of the binding site residues have been identified. However, most of these residues are obscured behind the C-loop that acts as a cover to the binding site. Thus, the mechanism by which the GABA molecule recognizes the binding site, and the pathway it takes to enter the binding site are both unclear. Through the completion and detailed analysis of 100 short, unbiased, independent molecular dynamics simulations, we have investigated this phenomenon of GABA entering the binding site. In each system, GABA was placed quasi-randomly near the binding site of a GABAA-R homology model, and atomistic simulations were carried out to observe the behavior of the GABA molecules. GABA fully entered the binding site in 19 of the 100 simulations. The pathway taken by these molecules was consistent and non-random; the GABA molecules approach the binding site from below, before passing up behind the C-loop and into the binding site. This binding pathway is driven by long-range electrostatic interactions, whereby the electrostatic field acts as a 'funnel' that sweeps the GABA molecules towards the binding site, at which point more specific atomic interactions take over. These findings define a nuanced mechanism whereby the GABAA-R uses the general zwitterionic features of the GABA molecule to identify a potential ligand some 2 nm away from the binding site.

  2. Altered levels of acylcarnitines, phosphatidylcholines, and sphingomyelins in peritoneal fluid from ovarian endometriosis patients.

    Science.gov (United States)

    Vouk, Katja; Ribič-Pucelj, Martina; Adamski, Jerzy; Rižner, Tea Lanišnik

    2016-05-01

    Endometriosis is a complex, polygenic, and estrogen-dependent disease that affects 6% to 10% of women of reproductive age, and 30% to 50% of women with infertility and/or pelvic pain. Surgical diagnosis of endometriosis is still the gold standard, as there are currently no diagnostic biomarkers available. Due to the invasive diagnostics, it can take up to 11 years before affected women are diagnosed and receive the appropriate treatment. We performed a targeted metabolomics study to search for potential semi-invasive biomarkers in peritoneal fluid from endometriosis patients. Our case-control study comprised 29 ovarian endometriosis patients and 36 healthy control women. The 148 metabolites included acylcarnitines, glycerophospholipids, and sphingolipids, which were quantified by electrospray ionization tandem mass spectrometry. The strength of association between the metabolites and the metabolite ratios and disease was assessed using crude and adjusted odds ratios. The best combination of biomarkers was then selected by performing step-wise logistic regression. Our analysis reveals significantly decreased concentrations of 10 metabolites, of carnitine and acylcarnitines (C0, C8:1, C6C4:1 DC, C10:1), phosphatidylcholines (PC aa C38:3, PC aa C38:4, PC aa C40:4, PC aa C40:5), and sphingomyelins (SM C16:1, SM C18:1), and 125 significantly altered metabolite ratios in patients versus control women. The best model includes two ratios: a carnitine to a phosphatidylcholine (C0/PC ae C36:0); and between two phosphatidylcholines (PC aa C30:0/PC ae C32:2). When adjusted for age, this provides sensitivity of 82.8% and specificity of 94.4%, with AUC of 0.944. Our study supports the importance of carnitine, phosphatidylcholine, and sphingomyelin metabolites in the pathophysiology of endometriosis, and confirms the potential for the combination of individual metabolite ratios to provide biomarkers for semi-invasive diagnostics. PMID:26921767

  3. Induced changes in the consumption of coffee alter ad libitum dietary intake and physical activity level.

    Science.gov (United States)

    Mosdøl, Annhild; Christensen, Benedicte; Retterstøl, Lars; Thelle, Dag S

    2002-03-01

    Dietary trials with subjects on a freely selected diet may be affected by unwanted behavioural changes. Few studies, if any, have examined changes in coffee consumption and possible concomitant changes in diet and health-related habits. The aim of the present study was to examine whether induced changes in coffee consumption lead to changes in food habits and leisure-time physical activity. Healthy, non-smoking coffee-drinkers (n 214) were asked to change their coffee habits in a controlled clinical trial on the metabolic effects of coffee. The participants were asked to maintain their usual dietary habits. Self-perceived changes in diet and physical activity during the 6-week intervention period were assessed at the end. In the analyses, the participants were rearranged into groups reflecting the difference in coffee intake during the trial as compared with habitual intake. Associations with changes in food intake or physical activity were analysed by Spearman rank correlation. Changes in intake of 'chocolate, sweets' (r 0.179, Ppastry' (r 0.306, P<0.001), and 'jam' r 0.198, P<0.05) showed positive associations with change in coffee intake during the trial. Negative associations were found for 'dishes with fish' (r -0.204, P<0.01) and many of the drinks as well as with physical activity (r -0.164, P<0.05). Induced changes in coffee intake seem to alter ad libitum intake of several foods. The recognized associations between health behaviours may have physiological explanations. PMID:12064335

  4. Pregnant rats show enhanced spatial memory, decreased anxiety, and altered levels of monoaminergic neurotransmitters

    Science.gov (United States)

    Macbeth, A.H.; Gautreaux, C.; Luine, V.N.

    2008-01-01

    Spatial memory, anxiety and central monoaminergic activities were measured in non-pregnant (NP) and pregnant females during two time periods of pregnancy: gestational day 7–9 (GD7, GD9) & gestation day 16–18 (GD16, GD18). Pregnant females discriminated between object locations on both test days on an object placement task, whereas NP females were unable to discriminate between locations. Pregnant females displayed decreased anxiety on the elevated plus maze on GD9 compared to NP females, followed by increased anxiety-like behavior on the elevated plus maze on GD18. Monoamine levels and activity (as indexed by turnover ratio) were measured in prefrontal cortex (PFC), CA1 and CA3 regions of the hippocampus (areas important for memory), and medial preoptic area (mPOA, an area important in display of maternal behaviors). In the PFC, NP females generally had higher monoamine levels and turnover ratios; however, norepinephrine (NE) turnover was higher in pregnant females at GD18. In the CA1 and CA3 regions of the hippocampus, monoamine levels and turnover ratios were generally higher during pregnancy, particularly on GD9. In the mPOA, pregnancy was associated with increases in NE activity, a previously unreported finding. The present study expands upon existing research indicating that pregnancy is beneficial to spatial memory and may decrease anxiety. Changes in monoamine levels and activity in specific brain regions indicate that the dopamine, norepinephrine and serotonin systems may contribute to the observed behavioral differences. PMID:18823955

  5. Cytochrome P450 levels are altered in patients with esophageal squamous-cell carcinoma

    DEFF Research Database (Denmark)

    Bergheim, I.; Wolfgarten, E.; Bollschweiler, E.;

    2007-01-01

    AIM: To investigate the role of cytochrome P450 (CYP) in the carcinogenesis of squamous-cell carcinoma (SCC) in human esophagus by determining expression patterns and protein levels of representative CYPs in esophageal tissue of patients with SCC and controls. METHODS: mRNA expression of CYP2E1, ...

  6. CTRP3 deficiency reduces liver size and alters IL-6 and TGFβ levels in obese mice.

    Science.gov (United States)

    Wolf, Risa M; Lei, Xia; Yang, Zhi-Chun; Nyandjo, Maeva; Tan, Stefanie Y; Wong, G William

    2016-03-01

    C1q/TNF-related protein 3 (CTRP3) is a secreted metabolic regulator whose circulating levels are reduced in human and rodent models of obesity and diabetes. Previously, we showed that CTRP3 infusion lowers blood glucose by suppressing gluconeogenesis and that transgenic overexpression of CTRP3 protects mice against diet-induced hepatic steatosis. Here, we used a genetic loss-of-function mouse model to further address whether CTRP3 is indeed required for metabolic homeostasis under normal and obese states. Both male and female mice lacking CTRP3 had similar weight gain when fed a control low-fat (LFD) or high-fat diet (HFD). Regardless of diet, no differences were observed in adiposity, food intake, metabolic rate, energy expenditure, or physical activity levels between wild-type (WT) and Ctrp3-knockout (KO) animals of either sex. Contrary to expectations, loss of CTRP3 in LFD- or HFD-fed male and female mice also had minimal or no impact on whole body glucose metabolism, insulin sensitivity, and fasting-induced hepatic gluconeogenesis. Unexpectedly, the liver sizes of HFD-fed Ctrp3-KO male mice were markedly reduced despite a modest increase in triglyceride content. Furthermore, liver expression of fat oxidation genes was upregulated in the Ctrp3-KO mice. Whereas the liver and adipose expression of profibrotic TGFβ1, as well as its serum levels, was suppressed in HFD-fed KO mice, circulating proinflammatory IL-6 levels were markedly increased; these changes, however, were insufficient to affect systemic metabolic outcome. We conclude that, although it is dispensable for physiological control of energy balance, CTRP3 plays a previously unsuspected role in modulating liver size and circulating cytokine levels in response to obesity. PMID:26670485

  7. High levels of psychopathic traits alters moral choice but not moral judgment

    Directory of Open Access Journals (Sweden)

    sebastien Tassy

    2013-06-01

    Full Text Available Psychopathy is a personality disorder frequently associated with immoral behaviors. Previous behavioral studies on the influence of psychopathy on moral decision have yielded contradictory results, possibly because they focused either on judgment (abstract evaluation or on choice of hypothetical action, two processes that may rely on different mechanisms. In this study, we explored the influence of the level of psychopathic traits on judgment and choice of hypothetical action during moral dilemma evaluation. A population of 102 students completed a questionnaire with ten moral dilemmas and nine non-moral dilemmas. The task included questions targeting both judgment (“Is it acceptable to ...in order to...?” and choice of hypothetical action (“Would you...in order to...?”. The level of psychopathic traits of each participant was evaluated with the Levenson Self-Report Psychopathy scale. Logistic regression fitted with the generalized estimating equations method analyses were conducted using responses to the judgment and choice tasks as the dependent variables and psychopathy scores as predictor. Results show that a high level of psychopathic traits, and more specifically those related to affective deficit, predicted a greater proportion of utilitarian responses for the choice but not for the judgment question. There was no first-order interaction between the level of psychopathic traits and other potential predictors. The relation between a high level of psychopathic traits and increased utilitarianism in choice of action but not in moral judgment may explain the contradictory results of previous studies where these two processes were not contrasted. It also gives further support to the hypothesis that choice of action endorsement and abstract judgment during moral dilemma evaluation are partially distinct neural and psychological processes. We propose that this distinction should be better taken into account in the evaluation of

  8. Cytochrome P450 levels are altered in patients with esophageal squamous-cell carcinoma

    Institute of Scientific and Technical Information of China (English)

    I Bergheim; E Wolfgarten; E Bollschweiler; AH H(o)lscher; C Bode; A Parlesak

    2007-01-01

    AIM:To investigate the role of cytochrome P450(CYP)in the carcinogenesis of squamous-cell carcinoma(SCC)in human esophagus by determining expression patterns and protein levels of representative CYPs in esophageal tissue of patients with SCC and controls.METHODS:mRNA expression of CYP2E1,CYP2C,CYP3A4,and CYP3A5 was determined using RT-PCR in both normal and malignant esophageal tissues of patients with untreated esophageal SCC(n = 21)and in controls(n = 10).Protein levels of CYP2E1,CYP2C8,CYP3A4,and CYP3A5 were measured by Western blot.RESULTS:Within the group of SCC patients,mRNA expression of CYP 3A4 and CYP2C was significantly lower in malignant tissue(-39% and -74%,respectively,P < 0.05)than in normal tissue.Similar results were found in CYP3A4 protein levels.Between groups,CYP3A4,CYP3A5,and CYP2C8 protein concentration was significantly higher in non-malignant tissue of SCC patients(4.8-,2.9-,and 1.9-fold elevation,P < 0.05)than in controls.In contrast,CYP2E1 protein levels were significantly higher in controls than in SCC patients (+46%,P < 0.05).CONCLUSION:Significant differences exist in protein levels of certain CYPs in non-malignant esophageal tissue (e.g.CYP2C8,CYP3A4,CYP3A5,and CYP2E1)between SCC patients and healthy subjects and may contribute to the development of SCC in the esophagus.

  9. GABA, its receptors, and GABAergic inhibition in mouse taste buds

    OpenAIRE

    Dvoryanchikov, Gennady; Huang, Yijen A.; Barro-Soria, Rene; Chaudhari, Nirupa; Roper, Stephen D.

    2011-01-01

    Taste buds consist of at least three principal cell types that have different functions in processing gustatory signals — glial-like Type I cells, Receptor (Type II) cells, and Presynaptic (Type III) cells. Using a combination of Ca2+ imaging, single cell RT-PCR, and immunostaining, we show that γ-amino butyric acid (GABA) is an inhibitory transmitter in mouse taste buds, acting on GABA-A and GABA-B receptors to suppress transmitter (ATP) secretion from Receptor cells during taste stimulation...

  10. Cloning and sequencing of mouse GABA transporter complementary DNA

    Institute of Scientific and Technical Information of China (English)

    TAMANTHONYC.W.; LIHEGUO; 等

    1994-01-01

    A cDNA encoding the mouse GABA transporter has been isolated and sequenced.The results show that the mouse GABA transporter cDNA differs from that of the rat by 60 base pairs at the open reading frame region but the deduced amino acid sequences of the two cDNAs are identical and both composed of 599 amino acids.However,the amino acid sequence is different from the sequence deduced from a recently published mouse GABA transporter cDNA.

  11. [Acute alterations of neurotransmitters levels in striatum of young rat after pilocarpine-induced status epilepticus].

    Science.gov (United States)

    de Freitas, Rivelilson Mendes; de Sousa, Francisca Cléa Florenço; Vasconcelos, Silvânia Maria Mendes; Viana, Glauce Socorro Barros; Fonteles, Marta Maria de França

    2003-06-01

    High doses of the muscarinic cholinergic agonist, pilocarpine, result in behavioural changes, seizures and status epilepticus in rats. The purpose of the present work is to invetigate the striatal neurotransmissors level in young rats after status epilepticus induced by pilocarpine. Wistar rats were treated with a single dose of pilocarpine (400mg/Kg; s.c.). Controls received saline. Young animals were closed observed for behavioural changes during 1 and 24h. In these periods, the animals that developed status epilepticus and didn't survive this acute phase of seizures had the brains removed and striatal neurotransmissors level determined by HPLC. The concentration of dopamine, serotonine, dihydroxyphenylacetic acid, 5-hydroxyindolacetic acid was reduced and an increase in 4-hydroxy-3-methoxy-phenylacetic acid was observed. These results suggest that cholinergic activation can interage with dopaminergic and serotonergic systems in acute phase of the convulsive process in immature striatum. PMID:12894279

  12. Alteration in the level of endogenous hypothalamic prostaglandins induced by delta 9-tetrahydrocannabinol in the rat.

    OpenAIRE

    Coupar, I M; Taylor, D A

    1982-01-01

    1 Whole brain and regional brain levels of prostaglandin E2 (PGE2)-like material have been determined following administration of delta 9-tetrahydrocannabinol (delta 9 -THC) in rats. 2 Intravenous administration of delta 9-THC 2 mg/kg, resulted in marked behavioural changes and hypothermia. The behavioural changes consisted mainly of catatonia (most apparent at 30 min after administration of delta 9-THC), followed by sedation (most evident at 60 min). Hypothermia was marked from 30 min after ...

  13. Fish oil supplementation alters levels of lipid mediators of inflammation in microenvironment of acute human wounds

    OpenAIRE

    McDaniel, Jodi C.; Massey, Karen; Nicolaou, Anna

    2011-01-01

    Chronic wounds often result from prolonged inflammation involving excessive polymorphonuclear leukocyte activity. Studies show that the ω-3 polyunsaturated fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) found in fish oils generate bioactive lipid mediators that reduce inflammation and polymorphonuclear leukocyte recruitment in numerous inflammatory disease models. This study’s purpose was to test the hypotheses that boosting plasma levels of EPA and DHA with oral suppl...

  14. Altered serous levels of monoamine neurotransmitter metabolites in patiens with refractory and non-refractory depression

    Institute of Scientific and Technical Information of China (English)

    Guiqing Zhang; Yanxia Zhang; Jianxia Yang; Min Hu; Yueqi Zhang; Xia Liang

    2012-01-01

    The study examined plasma metabolite changes of monoamine neurotransmitters in patients with treatment-resistant depression (TRD) and non-TRD before and after therapy. All 30 TRD and 30 non-TRD patients met the diagnostic criteria for a depressive episode in accordance with the International Classification of Diseases, Tenth Revision. Before treatment, and at 4, 6, and 8 weeks after treatment, the plasma metabolite products of monoamine neurotransmitters in TRD group, including 5-hydroxyindoleacetic acid, 3-methoxy-4-hydroxyphenyl ethylene glycol and homovanillic acid, were significantly lower than those in the non-TRD group. After two types of anti-depressive therapy with 5-serotonin and norepinephrine reuptake inhibitor, combined with psychotherapy, the Hamilton Depression Rating Scale scores were significantly reduced in both groups of patients, and the serous levels of 5-hydroxyindoleacetic acid and 3-methoxy-4-hydroxyphenyl ethylene glycol were significantly increased. In contrast, the homovanillic acid level exhibited no significant change. The levels of plasma metabolite products of peripheral monoamine neurotransmitters in depressive patients may predict the degree of depression and the therapeutic effects of treatment.

  15. GABAerges System in Leydigzellen und die Stimulation der Zellproliferation durch GABA

    OpenAIRE

    Geigerseder, Christof

    2005-01-01

    Im Rahmen dieser Arbeit wurde das den Neurotransmitter GABA synthetisierende Enzym GAD, der vesikuläre GABA-Transporter VGAT und GABA-Rezeptoren im Hoden von Nagern und Menschen nachgewiesen. Sowohl die Quelle von GABA, als auch GABA-Rezeptoren wurden in endokrinen Zellen des Hodens, den Testosteron bildenden Leydigzellen, lokalisiert. Weiterhin zeigten zellbiologische Untersuchungen, dass die etablierte Leydigzelllinie TM3 enzymatisch aktives GAD besitzt und auf GABAerge Stimulation mit eine...

  16. Fiat lux!: Phylogeny and Bioinformatics shed light on GABA functions in plants

    OpenAIRE

    Renault, Hugues

    2013-01-01

    The non-protein amino acid γ-aminobutyric acid (GABA) accumulates in plants in response to a wide variety of environmental cues. Recent data point toward an involvement of GABA in tricarboxylic acid (TCA) cycle activity and respiration, especially in stressed roots. To gain further insights into potential GABA functions in plants, phylogenetic and bioinformatic approaches were undertaken. Phylogenetic reconstruction of the GABA transaminase (GABA-T) protein family revealed the monophyletic na...

  17. Sleep-deprivation induces changes in GABA(B and mGlu receptor expression and has consequences for synaptic long-term depression.

    Directory of Open Access Journals (Sweden)

    Ramakrishna Tadavarty

    Full Text Available Long term depression (LTD in the CA1 region of the hippocampus, induced with a 20-Hz, 30 s tetanus to Schaffer collaterals, is enhanced in sleep-deprived (SD rats. In the present study, we investigated the role of metabotropic glutamate receptors (mGluRs, γ-aminobutyric acid (GABA B receptors (GABA(B-Rs and N-methyl-D-aspartic acid receptors (NMDARs in the LTD of the population excitatory postsynaptic potential (pEPSP. The requirement of Ca(2+ from L- and T-type voltage-gated calcium channels (VGCCs and intracellular stores was also studied. Results indicate that mGluRs, a release of Ca(2+ from intracellular stores and GABA(B-Rs are required for LTD. Interestingly, while mGlu1Rs seem to be involved in both short-term depression and LTD, mGlu5Rs appear to participate mostly in LTD. CGP 55845, a GABA(B-R antagonist, partially suppressed LTD in normally sleeping (NS rats, while completely blocking LTD in SD rats. Moreover, GS-39783, a positive allosteric modulator for GABA(B-R, suppressed the pEPSP in SD, but not NS rats. Since both mGluRs and GABA(B-Rs seem to be involved in the LTD, especially in SD rats, we examined if the receptor expression pattern and/or dimerization changed, using immunohistochemical, co-localization and co-immunoprecipitation techniques. Sleep-deprivation induced an increase in the expression of GABA(B-R1 and mGlu1αR in the CA1 region of the hippocampus. In addition, co-localization and heterodimerization between mGlu1αR/GABA(B-R1 and mGlu1αR/GABA(B-R2 is enhanced in SD rats. Taken together, our findings present a novel form of LTD sensitive to the activation of mGluRs and GABA(B-Rs, and reveal, for the first time, that sleep-deprivation induces alterations in the expression and dimerization of these receptors.

  18. Ethanol consumption during early pregnancy alters the disposition of tangentially migrating GABAergic interneurons in the fetal cortex.

    Science.gov (United States)

    Cuzon, Verginia C; Yeh, Pamela W L; Yanagawa, Yuchio; Obata, Kunihiko; Yeh, Hermes H

    2008-02-20

    Consumption of alcohol (ethanol) during pregnancy can lead to developmental defects in the offspring, the most devastating being the constellation of symptoms collectively referred to as fetal alcohol syndrome (FAS). In the brain, a hallmark of FAS is abnormal cerebral cortical morphology consistent with insult during corticogenesis. Here, we report that exposure to a relatively low level of ethanol in utero (average maternal and fetal blood alcohol level of 25 mg/dl) promotes premature tangential migration into the cortical anlage of primordial GABAergic interneurons, including those originating in the medial ganglionic eminence (MGE). This ethanol-induced effect was evident in vivo at embryonic day 14.5 (E14.5) in GAD67 knock-in and BAC-Lhx6 embryos, as well as in vitro in isotypic telencephalic slice cocultures obtained from E14.5 embryos exposed to ethanol in utero. Analysis of heterotypic cocultures indicated that both cell-intrinsic and -extrinsic factors contribute to the aberrant migratory profile of MGE-derived cells. In this light, we provide evidence for an interaction between ethanol exposure in utero and the embryonic GABAergic system. Exposure to ethanol in utero elevated the ambient level of GABA and increased the sensitivity to GABA of MGE-derived cells. Our results uncovered for the first time an effect of ethanol consumption during pregnancy on the embryonic development of GABAergic cortical interneurons. We propose that ethanol exerts its effect on the tangential migration of GABAergic interneurons extrinsically by modulating extracellular levels of GABA and intrinsically by altering GABA(A) receptor function. PMID:18287502

  19. Levels of serum immunomodulators and alterations with electroconvulsive therapy in treatment-resistant major depression.

    Science.gov (United States)

    Zincir, Serkan; Öztürk, Pelin; Bilgen, Ali Emrah; İzci, Filiz; Yükselir, Cihad

    2016-01-01

    Studies in recent years have indicated that neuroimmunological events and immune activation may have a place in the etiology of depression. It has been suggested from data that there is a causal relationship between activation of the immune system and excessive release of proinflammatory cytokines, such as interleukin 1 (IL-1), IL-6, and tumor necrosis factor-alpha (TNF-alpha), and the etiology of depression. Although the mechanism of action of electroconvulsive therapy (ECT) is unclear, there is evidence that it can reduce cytokines and immune system changes. In our study, we aimed to determine how levels of serum immunomodulators were affected by ECT in major depression patients. This study was conducted on 50 patients with treatment-resistant major depression. The data of the patients were compared with 30 healthy individuals with similar demographic characteristics. A clinical response occurred in the patients and at the end of therapy, IL-1, IL-6, TNF-alpha, IL-10, IL-4, and interferon-gamma levels were measured. The disease severity was assessed with the 17-item Hamilton Depression Rating Scale. Data analysis was performed using SPSS Version 15. Significant differences were determined between the patients with major depression and control group with respect to basal serum IL-1, IL-6, TNF-alpha, IL-10, IL-4, and interferon-gamma levels. ECT treatment was shown to reduce these differences. ECT may cause significant changes in the activity of the immune system. The consideration of the relationship between the immune endocrine neurotransmitter systems could contribute to new theories regarding the mechanism of antidepressant treatment and biology of depression. PMID:27366071

  20. Alterations in the level of OFQ/N-IR in rat brain regions by cocaine

    OpenAIRE

    Lutfy, Kabirullah; Lam, Hoa; Narayanan, Shridhar

    2008-01-01

    We have previously shown that administration of orphanin FQ/nociceptin (OFQ/N), the endogenous ligand of the opioid receptor-like (ORL-1) receptor, into the lateral ventricles or VTA blocked cocaine sensitization. In the present study, we determined the effect of acute and chronic cocaine treatment on the level of endogenous OFQ/N in rat brain regions. Male Sprague Dawley rats were tested for motor activity in response to saline or cocaine (20 mg/kg) injection once daily for three consecutive...

  1. LPS alters pattern of sickness behavior but does not affect glutathione level in aged male rats.

    Science.gov (United States)

    Wrotek, Sylwia; Jędrzejewski, Tomasz; Nowakowska, Anna; Kozak, Wiesław

    2016-08-01

    Behavioral symptoms of sickness, such as fever and motor activity are a coordinated set of changes that develop during infection. The aim of study was to compare the sickness behaviour (SB) in healthy old and young rats treated with pyrogenic dose of endotoxin and to check their glutathione level. Before experimentation male Wistar rats were selected according to standard body mass, motor activity, and white blood cells count. Intraperitoneal injection of lipopolysaccharide (LPS) from E. coli was used to provoke SB. The level of liver glutathione, interleukin (IL) -6, deep body temperature (Tb) and motor activity were measured. Glutathione level in old and young rats did not differ significantly. In both young and old rats LPS administration provoked fever (the mean value of Tb was 38.06 ± 0.01 °C in old rats, and 38.19 ± 0.06 °C in young rats). LPS injection affected night-time activity in both groups (12 h averages were 1.56 ± 0.40 counts in old LPS-treated rats vs 2.74 ± 0.53 counts in not-treated old rats and 3.44 ± 0.60 counts for young LPS-treated vs 4.28 ± 0.57 counts for young not-treated rats). The injection of LPS provoked an elevation of plasma IL-6 concentration (from values below the lowest detectable standard in not-treated groups of animals to 6322.82 ± 537.00 pg/mL in old LPS-treated rats and 7415.62 ± 451.88 pg/mL in young LPS-treated rats). Based on these data, we conclude that good health of aged rats prevents decrease in the glutathione level. Old rats are still able to develop SB in response to pyrogenic dose of LPS, although its components have changed pattern compared to young animals. PMID:26829940

  2. Protein engineering strategies with potential applications for altering clinically relevant cellular pathways at the protein level.

    Science.gov (United States)

    Regan, Lynne; Hinrichsen, Michael R; Oi, Curran

    2016-05-01

    All diseases can be fundamentally viewed as the result of malfunctioning cellular pathways. Protein engineering offers the potential to develop new tools that will allow these dysfunctional pathways to be better understood, in addition to potentially providing new routes to restore proper function. Here we discuss different approaches that can be used to change the intracellular activity of a protein by intervening at the protein level: targeted protein sequestration, protein recruitment, protein degradation, and selective inhibition of binding interfaces. The potential of each of these tools to be developed into effective therapeutic treatments will also be discussed, along with any major barriers that currently block their translation into the clinic. PMID:27031866

  3. Lack of Platelet-Activating Factor Receptor Attenuates Experimental Food Allergy but Not Its Metabolic Alterations regarding Adipokine Levels

    Science.gov (United States)

    Batista, Nathália Vieira; Fonseca, Roberta Cristelli; Perez, Denise; Pereira, Rafaela Vaz Sousa; de Lima Alves, Juliana; Pinho, Vanessa; Faria, Ana Maria Caetano; Cara, Denise Carmona

    2016-01-01

    Platelet-activating factor (PAF) is known to be an important mediator of anaphylaxis. However, there is a lack of information in the literature about the role of PAF in food allergy. The aim of this work was to elucidate the participation of PAF during food allergy development and the consequent adipose tissue inflammation along with its alterations. Our data demonstrated that, both before oral challenge and after 7 days receiving ovalbumin (OVA) diet, OVA-sensitized mice lacking the PAF receptor (PAFR) showed a decreased level of anti-OVA IgE associated with attenuated allergic markers in comparison to wild type (WT) mice. Moreover, there was less body weight and adipose tissue loss in PAFR-deficient mice. However, some features of inflamed adipose tissue presented by sensitized PAFR-deficient and WT mice after oral challenge were similar, such as a higher rate of rolling leukocytes in this tissue and lower circulating levels of adipokines (resistin and adiponectin) in comparison to nonsensitized mice. Therefore, PAF signaling through PAFR is important for the allergic response to OVA but not for the adipokine alterations caused by this inflammatory process. Our work clarifies some effects of PAF during food allergy along with its role on the metabolic consequences of this inflammatory process. PMID:27314042

  4. Advanced age, altered level of consciousness and a new diagnosis of diabetes are independently associated with hypernatreamia in hyperglycaemic crisis

    Directory of Open Access Journals (Sweden)

    Ogbera Anthonia O

    2011-04-01

    Full Text Available Abstract Background There is limited literature on hypernatreamia in the setting of hyperglycaemic crisis. This is despite the fact that the presence of hypernatreamia may impact on the classification of hyperglycaemic crisis and its management particularly with regards to the nature of fluid therapy. We determined the prevalence of hypernatreamia and its associated factors at presentation for hyperglycaemic crisis. Methods This was a retrospective review of data for hyperglycaemic crisis admissions in Nelson Mandela Academic Hospital, Mthatha, South Africa. The prevalence of hypernatreamia (uncorrected Serum Sodium at presentation >145 mmol/L was determined. Hyperosmolality was defined by calculated effective osmolality >320 mosmols/Kg. Multivariate logistic regression was undertaken using variables that were statistically significant in univariate analysis to ascertain those that were independently associated (Odds Ratio (OR with 95% Confidence Interval (CI with hypernatreamia. Results The prevalence of hypernatreamia in our admissions for hyperglycaemic crisis was 11.7% (n = 32/273 including 171 females and 102 males. All admissions with hypernatreamia met the criteria for hyperosmolality. Age ≥ 60 years (OR = 3.9 95% CI 1.3-12.3; P = 0.018, Altered level of consciousness (OR = 8.8 95% CI 2.3-32.8; P Conclusion The prevalence rate of hypernatreamia in hyperglycaemic admissions was high with all hypernatreamic admissions meeting the criteria for hyperosmolality. Advanced age, altered conscious level and a new diagnosis of diabetes were independently associated with hypernatreamia.

  5. Alterative LEU designs for the FRM-II with power levels of 20-22 MW

    International Nuclear Information System (INIS)

    Alternative LEU Designs for the FRM-II have been developed by the RERTR Program at Argonne National Laboratory (ANL) at the request of an FRM-II Expert Group established by the German Federal Government in January 1999 to evaluate the options for using LEU fuel instead of HEU fuel in cores with power levels of 20 MW. The ANL designs would use the same building structure and maintain as many of the HEU design features as practical. The range of potential LEU fuels was expanded from previous studies to include already-tested silicide fuels with uranium densities up to 6.7 g/cm3 and the new U-Mo fuels that show excellent prospects for achieving uranium densities in the 8-9 g/cm3 range. For each of the LEU cores; the design parameters were chosen to match the 50 day cycle length of the HEU core and to maximize the thermal neutron flux in the Cold Neutron Source and beam tubes. The studies concluded that an LEU core with a diameter of about 29 cm instead of 24 cm in HEU design and operating at a power level of 20 MW would have thermal neutron fluxes that are 0.85 times that of the HEU design at the center of the Cold Neutron Source. With a potential future upgrade to a power of 22 MW, this ratio would increase to 0.93

  6. Alterative LEU designs for the FRM-II with power levels of 20-22 MW.

    Energy Technology Data Exchange (ETDEWEB)

    Hanan, N. A.; Smith, R. S.; Matos, J. E.

    1999-09-27

    Alternative LEU Designs for the FRM-II have been developed by the RERTR Program at Argonne National Laboratory (ANL) at the request of an FRM-II Expert Group established by the German Federal Government in January 1999 to evaluate the options for using LEU fuel instead of HEU fuel in cores with power levels of 20 MW. The ANL designs would use the same building structure and maintain as many of the HEU design features as practical. The range of potential LEU fuels was expanded from previous studies to include already-tested silicide fuels with uranium densities up to 6.7 g/cm{sup 3} and the new U-Mo fuels that show excellent prospects for achieving uranium densities in the 8-9 g/cm{sup 3} range. For each of the LEU cores; the design parameters were chosen to match the 50 day cycle length of the HEU core and to maximize the thermal neutron flux in the Cold Neutron Source and beam tubes. The studies concluded that an LEU core with a diameter of about 29 cm instead of 24 cm in HEU design and operating at a power level of 20 MW would have thermal neutron fluxes that are 0.85 times that of the HEU design at the center of the Cold Neutron Source. With a potential future upgrade to a power of 22 MW, this ratio would increase to 0.93.

  7. Lesions of nucleus accumbens affect morphine-induced release of ascorbic acid and GABA but not of glutamate in rats.

    Science.gov (United States)

    Sun, Ji Y; Yang, Jing Y; Wang, Fang; Wang, Jian Y; Song, Wu; Su, Guang Y; Dong, Ying X; Wu, Chun F

    2011-10-01

    Our previous studies have shown that local perfusion of morphine causes an increase of extracellular ascorbic acid (AA) levels in nucleus accumbens (NAc) of freely moving rats. Lines of evidence showed that glutamatergic and GABAergic were associated with morphine-induced effects on the neurotransmission of the brain, especially on the release of AA. In the present study, the effects of morphine on the release of extracellular AA, γ-aminobutyric acid (GABA) and glutamate (Glu) in the NAc following bilateral NAc lesions induced by kainic acid (KA) were studied by using the microdialysis technique, coupled to high performance liquid chromatography with electrochemical detection (HPLC-ECD) and fluorescent detection (HPLC-FD). The results showed that local perfusion of morphine (100 µM, 1 mM) in NAc dose-dependently increased AA and GABA release, while attenuated Glu release in the NAc. Naloxone (0.4 mM) pretreated by local perfusion to the NAc, significantly blocked the effects of morphine. After NAc lesion by KA (1 µg), morphine-induced increase in AA and GABA were markedly eliminated, while decrease in Glu was not affected. The loss effect of morphine on AA and GABA release after KA lesion could be recovered by GABA agonist, musimol. These results indicate that morphine-induced AA release may be mediated at least by µ-opioid receptor. Moreover, this effect of morphine possibly depend less on the glutamatergic afferents, but more on the GABAergic circuits within this nucleus. Finally, AA release induced by local perfusion of morphine may be GABA-receptor mediated and synaptically localized in the NAc. PMID:20731632

  8. Minocycline treatment inhibits microglial activation and alters spinal levels of endocannabinoids in a rat model of neuropathic pain

    Directory of Open Access Journals (Sweden)

    Elphick Maurice R

    2009-07-01

    Full Text Available Abstract Activation of spinal microglia contributes to aberrant pain responses associated with neuropathic pain states. Endocannabinoids (ECs are present in the spinal cord, and inhibit nociceptive processing; levels of ECs may be altered by microglia which modulate the turnover of endocannabinoids in vitro. Here, we investigate the effect of minocycline, an inhibitor of activated microglia, on levels of the endocannabinoids anandamide and 2-arachidonoylglycerol (2-AG, and the related compound N-palmitoylethanolamine (PEA, in neuropathic spinal cord. Selective spinal nerve ligation (SNL in rats resulted in mechanical allodynia and the presence of activated microglia in the ipsilateral spinal cord. Chronic daily treatment with minocycline (30 mg/kg, ip for 14 days significantly reduced the development of mechanical allodynia at days 5, 10 and 14 post-SNL surgery, compared to vehicle-treated SNL rats (P P P P P

  9. Gene expression changes in GABA(A receptors and cognition following chronic ketamine administration in mice.

    Directory of Open Access Journals (Sweden)

    Sijie Tan

    Full Text Available Ketamine is a well-known anesthetic agent and a drug of abuse. Despite its widespread use and abuse, little is known about its long-term effects on the central nervous system. The present study was designed to evaluate the effect of long-term (1- and 3-month ketamine administration on learning and memory and associated gene expression levels in the brain. The Morris water maze was used to assess spatial memory and gene expression changes were assayed using Affymetrix Genechips; a focus on the expression of GABA(A receptors that mediate a tonic inhibition in the brain, was confirmed by quantitative real-time PCR and western blot. Compared with saline controls, there was a decline in learning and memory performance in the ketamine-treated mice. Genechip results showed that 110 genes were up-regulated and 136 genes were down-regulated. An ontology analysis revealed the most significant effects of ketamine were on GABA(A receptors. In particular, there was a significant up-regulation of both mRNA and protein levels of the alpha 5 subunit (Gabra5 of the GABA(A receptors in the prefrontal cortex. In conclusion, chronic exposure to ketamine impairs working memory in mice, which may be explained at least partly by up-regulation of Gabra5 subunits in the prefrontal cortex.

  10. Proteins with altered levels in plasma from glioblastoma patients as revealed by iTRAQ-based quantitative proteomic analysis.

    Directory of Open Access Journals (Sweden)

    Poonam Gautam

    Full Text Available Glioblastomas (GBMs are the most common and lethal primary tumors of the central nervous system with high level of recurrence despite aggressive therapy. Tumor-associated proteins/peptides may appear in the plasma of these patients as a result of disruption of the blood-brain barrier in them, raising the scope for development of plasma-based tests for diagnosis and monitoring the disease. With this objective, we analyzed the levels of proteins present in the plasma from GBM patients using an iTRAQ based LC-MS/MS approach. Analysis with pooled plasma specimens from the patient and healthy control samples revealed high confidence identification of 296 proteins, of which 61 exhibited a fold-change ≥1.5 in the patient group. Forty-eight of them contained signal sequence. A majority have been reported in the differentially expressed transcript or protein profile of GBM tissues; 6 have been previously studied as plasma biomarkers for GBM and 16 for other types of cancers. Altered levels of three representative proteins-ferritin light chain (FTL, S100A9, and carnosinase 1 (CNDP1-were verified by ELISA in a test set of ten individual plasma specimens. FTL is an inflammation marker also implicated in cancer, S100A9 is an important member of the Ca(2+ signaling cascade reported to be altered in GBM tissue, and CNDP1 has been reported for its role in the regulation of the levels of carnosine, implicated as a potential drug for GBM. These and other proteins in the dataset may form useful starting points for further clinical investigations for the development of plasma-based biomarker panels for GBM.

  11. Serotonin markers show altered transcription levels in an experimental pig model of mitral regurgitation

    DEFF Research Database (Denmark)

    Cremer, Signe Emilie; Zois, Nora Elisabeth; Moesgaard, S. G.; Ravn, Nathja; Cirera Salicio, Susanna; Honge, J. L.; Smerup, Morten Holdgaard; Hasenkam, J. Michael; Sloth, E.; Leifsson, Páll S.; Falk, Bo Torkel; Oyama, M. A.; Orton, C.; Martinussen, Torben; Olsen, Lisbeth Høier

    2015-01-01

    muscle (AP) and left ventricle (LV). MV 5-HT2BR was also analysed with immunohistochemistry (IHC) in relation to histological lesions and valvular myofibroblasts. All 5-HTR mRNAs were up-regulated in MV compared to AP and LV (P <0.01). In contrast, SERT and TPH-1 were up-regulated in AP and LV compared...... to MV (P <0.05). In MV, mRNA levels were increased for 5-HT2BR (P = 0.02) and decreased for SERT (P = 0.03) in sMR vs. CON. There were no group differences in 5-HT2BR staining (IHC) but co-localisation was found with α-SMA-positive cells in 91% of all valves and with 33% of histological lesions. In...

  12. Supraphysiological Levels of Quercetin Glycosides are Required to Alter Mineralization in Saos2 Cells.

    Science.gov (United States)

    Nash, Leslie A; Peters, Sandra J; Sullivan, Philip J; Ward, Wendy E

    2016-01-01

    Flavonoid intake is positively correlated to bone mineral density (BMD) in women. Flavonoids such as quercetin exhibit strong anti-oxidant and anti-inflammatory activity that may be beneficial for bone health. Quercetin, previously shown to positively influence osteoblasts, is metabolized into glycosides including rutin and hyperoside. We compared the effects of these glycosides on mineralization in human osteoblast (Saos2) cells. Administration of rutin (≥25 µM) and hyperoside (≥5 µM) resulted in higher mineral content, determined using the alizarin red assay. This was accompanied by higher alkaline phosphatase activity with no cell toxicity. The expression of osteopontin, sclerostin, TNFα and IL6, known stimuli for decreasing osteoblast activity, were reduced with the addition of rutin or hyperoside. In summary, rutin and hyperoside require supraphysiological levels, when administered individually, to positively influence osteoblast activity. This information may be useful in developing nutraceuticals to support bone health. PMID:27136576

  13. Supraphysiological Levels of Quercetin Glycosides are Required to Alter Mineralization in Saos2 Cells

    Science.gov (United States)

    Nash, Leslie A.; Peters, Sandra J.; Sullivan, Philip J.; Ward, Wendy E.

    2016-01-01

    Flavonoid intake is positively correlated to bone mineral density (BMD) in women. Flavonoids such as quercetin exhibit strong anti-oxidant and anti-inflammatory activity that may be beneficial for bone health. Quercetin, previously shown to positively influence osteoblasts, is metabolized into glycosides including rutin and hyperoside. We compared the effects of these glycosides on mineralization in human osteoblast (Saos2) cells. Administration of rutin (≥25 µM) and hyperoside (≥5 µM) resulted in higher mineral content, determined using the alizarin red assay. This was accompanied by higher alkaline phosphatase activity with no cell toxicity. The expression of osteopontin, sclerostin, TNFα and IL6, known stimuli for decreasing osteoblast activity, were reduced with the addition of rutin or hyperoside. In summary, rutin and hyperoside require supraphysiological levels, when administered individually, to positively influence osteoblast activity. This information may be useful in developing nutraceuticals to support bone health. PMID:27136576

  14. Unexpected rates of chromosomal instabilities and alterations of hormone levels in Namibian uranium miners.

    Science.gov (United States)

    Zaire, R; Notter, M; Riedel, W; Thiel, E

    1997-05-01

    A common problem in determining the health consequences of radiation exposure is factoring out other carcinogenic influences. The conditions in Namibia provide a test case for distinguishing the effects of long-term low-dose exposure to uranium from the other environmental factors because of good air quality and the lack of other industries with negative health effects. Present records indicate a much higher prevalence of cancer among male workers in the open-pit uranium mine in Namibia compared with the general population. The objective of the present study was to determine whether long-term exposure to low doses of uranium increases the risk of a biological radiation damage which would lead to malignant diseases and to derive a dose-response model for these miners. To investigate this risk, we measured uranium excretion in urine, neutrophil counts and the serum level of FSH, LH and testosterone and analyzed chromosome aberrations in whole blood cells using fluorescence in situ hybridization. A representative cohort of 75 non-smoking, HIV-negative miners was compared to a control group of 31 individuals with no occupational history in mining. A sixfold increase in uranium excretion among the miners compared to the controls was recorded (P atomic bomb or the Chernobyl accident. We conclude that the miners exposed to uranium are at an increased risk to acquire various degrees of genetic damage, and that the damage may be associated with an increased risk for malignant transformation. As expected, the chronic radiation injury of the hematopoietic system resulted in low neutrophil counts. Also, low hormone levels probably reflect damage to the gonadal endocrine system. PMID:9146703

  15. The four human ¿-aminobutyric acid (GABA) transporters

    DEFF Research Database (Denmark)

    Kvist, Trine; Christiansen, Bolette; Jensen, Anders Asbjørn;

    2009-01-01

    The neurotransmission mediated by gamma-aminobutyric acid (GABA) in the mammalian brain is terminated by a family of four GABA transporters (GATs). Inhibition of GATs is currently used in the treatment of epilepsy and these proteins are generally considered as important drug targets. In this study......, we perform the first elaborate pharmacological characterization of all four human GAT subtypes. We conduct the experiments in parallel in a [3H]GABA uptake assay using 14 standard GAT substrates and inhibitors. This setup enables direct comparison of the absolute values of inhibitory activities of...... subtype, no subtype selective ligands have been reported for the three remaining GATs. Given the potential therapeutic relevance of the individual GAT subtypes, a search for novel structures displaying selectivities for specific GAT subtypes is important. In this study, we validate our [3H]GABA uptake...

  16. A homogeneous assay to assess GABA transporter activity.

    Science.gov (United States)

    Kopec, Karla K; McKenna, Beth Ann; Pauletti, Daniel

    2005-10-01

    This unit describes a convenient functional uptake assay for GABA transport into cell lines transiently transfected with GABA transporter-1 (GAT-1) and other GAT isoforms. This facile, homogeneous assay allows for the determination of K(m), V(max), and K(i) values. The assay utilizes commercially available microtiter plates that contain scintillant embedded in the bottom of the wells. Whereas a signal is generated as the cell accumulates the labeled neurotransmitter, label in the medium is undetected. While GABA uptake is observed in several cell lines transfected with GAT-1, K(m) values for GABA uptake may vary with the cell line. This indicates that the choice of cell line is an important consideration when conducting uptake assays. PMID:21953387

  17. [GABA-Receptors in Modulation of Fear Memory Extinction].

    Science.gov (United States)

    Dubrovina, N I

    2016-01-01

    GABA is the major inhibitory neurotransmitter in the central nervous system determining the efficacy of neuronal interaction. GABA-receptors play a key role in different aspects of fear memory--acquisition and consolidation, retention, reconsolidation and extinction. Extinction is an important behavioural phenomenon which allows organism to adapt its behavior to a changing environment. Extinction of fear memory is a form of new inhibitory learning which interferes with expression of the initial acquired fear conditioning. Resistance to extinction is symptom of depression and posttraumatic stress disorder. The aim of the present review was to summarize own and literary data about GABAergic modulation of fear extinction and pharmacological correction of extinction impairment at influences on GABA(A)- and GABA(B)- receptors. PMID:27538279

  18. Endogenous synthesis of taurine and GABA in rat ocular tissues

    International Nuclear Information System (INIS)

    The endogenous production of taurine and γ-aminobutyric acid (GABA) in rat ocular tissues was investigated. The activities of taurine-producing enzyme, cysteine sulfinic acid decarboxylase (CSAD), and GABA-synthesizing enzyme, glutamic acid decarboxylase (GAD), were observed in the retina, lens, iris-ciliary body and cornea. The highest specific activity of CSAD was in the cornea and that of GAD in the retina. The discrepancy between CSAD activity and taurine content within the ocular tissues indicates that intra- or extraocular transport processes may regulate the concentration of taurine on the rat eye. The GAD activity and the content of GABA were distributed in parallel within the rat ocular tissues. The quantitative results suggest that the GAD/GABA system has functional significance only in the retina of the rat eye. (author)

  19. Accuracy and stability of measuring GABA, glutamate, and glutamine by proton magnetic resonance spectroscopy: A phantom study at 4 Tesla

    Science.gov (United States)

    Henry, Michael E.; Lauriat, Tara L.; Shanahan, Meghan; Renshaw, Perry F.; Jensen, J. Eric

    2011-02-01

    Proton magnetic resonance spectroscopy has the potential to provide valuable information about alterations in gamma-aminobutyric acid (GABA), glutamate (Glu), and glutamine (Gln) in psychiatric and neurological disorders. In order to use this technique effectively, it is important to establish the accuracy and reproducibility of the methodology. In this study, phantoms with known metabolite concentrations were used to compare the accuracy of 2D J-resolved MRS, single-echo 30 ms PRESS, and GABA-edited MEGA-PRESS for measuring all three aforementioned neurochemicals simultaneously. The phantoms included metabolite concentrations above and below the physiological range and scans were performed at baseline, 1 week, and 1 month time-points. For GABA measurement, MEGA-PRESS proved optimal with a measured-to-target correlation of R2 = 0.999, with J-resolved providing R2 = 0.973 for GABA. All three methods proved effective in measuring Glu with R2 = 0.987 (30 ms PRESS), R2 = 0.996 (J-resolved) and R2 = 0.910 (MEGA-PRESS). J-resolved and MEGA-PRESS yielded good results for Gln measures with respective R2 = 0.855 (J-resolved) and R2 = 0.815 (MEGA-PRESS). The 30 ms PRESS method proved ineffective in measuring GABA and Gln. When measurement stability at in vivo concentration was assessed as a function of varying spectral quality, J-resolved proved the most stable and immune to signal-to-noise and linewidth fluctuation compared to MEGA-PRESS and 30 ms PRESS.

  20. The glutamate-glutamine(GABA cycle: importance of late postnatal development and potential reciprocal interactions between biosynthesis and degradation

    Directory of Open Access Journals (Sweden)

    Leif eHertz

    2013-05-01

    Full Text Available The gold standard for studies of glutamate-glutamine(GABA cycling and its connections to brain biosynthesis from glucose of glutamate and GABA and their subsequent metabolism are the elegant in vivo studies by 13C magnetic resonance spectroscopy (NMR, showing the large fluxes in the cycle. However, simpler experiments in intact brain tissue (e.g. immunohistochemistry, brain slices, cultured brain cells and mitochondria have also made important contributions to the understanding of details, mechanisms and functional consequences of glutamate/GABA biosynthesis and degradation. The purpose of this review is to attempt to integrate evidence from different sources regarding i the enzyme(s responsible for the initial conversion of -ketoglutarate to glutamate; ii the possibility that especially glutamate oxidation is essentially confined to astrocytes; and iii the ontogenetically very late onset and maturation of glutamine-glutamate(GABA cycle function. Pathway models based on the functional importance of aspartate for glutamate synthesis suggest the possibility of interacting pathways for biosynthesis and degradation of glutamate and GABA and the use of transamination as the default mechanism for initiation of glutamate oxidation. The late development and maturation are related to the late cortical gliogenesis and convert brain cortical function from being purely neuronal to becoming neuronal-astrocytic. This conversion is associated with huge increases in energy demand and production, and the character of potentially incurred gains of function are discussed. These may include alterations in learning mechanisms, in mice indicated by lack of pairing of odor learning with aversive stimuli in newborn animals but the development of such an association 10-12 days later. The possibility is suggested that analogous maturational changes may contribute to differences in the way learning is accomplished in the newborn human brain and during later development.

  1. Time Course of Behavioral Alteration and mRNA Levels of Neurotrophic Factor Following Stress Exposure in Mouse.

    Science.gov (United States)

    Hashikawa, Naoya; Ogawa, Takumi; Sakamoto, Yusuke; Ogawa, Mami; Matsuo, Yumi; Zamami, Yoshito; Hashikawa-Hobara, Narumi

    2015-08-01

    Stress is known to affect neurotrophic factor expression, which induces depression-like behavior. However, whether there are time-dependent changes in neurotrophic factor mRNA expression following stress remains unclear. In the present study, we tested whether chronic stress exposure induces long-term changes in depression-related behavior, serum corticosterone, and hippocampal proliferation as well as neurotrophic factor family mRNA levels, such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and ciliary neurotrophic factor (CNTF), in the mouse hippocampus. The mRNA level of neurotrophic factors (BDNF, NGF, NT-3, and CNTF) was measured using the real-time PCR. The serum corticosterone level was evaluated by enzyme-linked immunosorbent assay, and, for each subject, the hippocampal proliferation was examined by 5-bromo-2-deoxyuridine immunostaining. Mice exhibited depression-like behavior in the forced-swim test (FST) and decreased BDNF mRNA and hippocampal proliferation in the middle of the stress exposure. After 15 days of stress exposure, we observed increased immobility in the FST, serum corticosterone levels, and BDNF mRNA levels and degenerated hippocampal proliferation, maintained for at least 2 weeks. Anhedonia-like behavior in the sucrose preference test and NGF mRNA levels were decreased following 15 days of stress. NGF mRNA levels were significantly higher 1 week after stress exposure. The current data demonstrate that chronic stress exposure induces prolonged BDNF and NGF mRNA changes and increases corticosterone levels and depression-like behavior in the FST, but does not alter other neurotrophic factors or performance in the sucrose preference test. PMID:25820756

  2. Proteasome inhibitors alter levels of intracellular peptides in HEK293T and SH-SY5Y cells.

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    Sayani Dasgupta

    Full Text Available The proteasome cleaves intracellular proteins into peptides. Earlier studies found that treatment of human embryonic kidney 293T (HEK293T cells with epoxomicin (an irreversible proteasome inhibitor generally caused a decrease in levels of intracellular peptides. However, bortezomib (an antitumor drug and proteasome inhibitor caused an unexpected increase in the levels of most intracellular peptides in HEK293T and SH-SY5Y cells. To address this apparent paradox, quantitative peptidomics was used to study the effect of a variety of other proteasome inhibitors on peptide levels in HEK293T and SH-SY5Y cells. Inhibitors tested included carfilzomib, MG132, MG262, MLN2238, AM114, and clasto-Lactacystin β-lactone. Only MG262 caused a substantial elevation in peptide levels that was comparable to the effect of bortezomib, although carfilzomib and MLN2238 elevated the levels of some peptides. To explore off-target effects, the proteosome inhibitors were tested with various cellular peptidases. Bortezomib did not inhibit tripeptidyl peptidase 2 and only weakly inhibited cellular aminopeptidase activity, as did some of the other proteasome inhibitors. However, potent inhibitors of tripeptidyl peptidase 2 (butabindide and cellular aminopeptidases (bestatin did not substantially alter the peptidome, indicating that the increase in peptide levels due to proteasome inhibitors is not a result of peptidase inhibition. Although we cannot exclude other possibilities, we presume that the paradoxical increase in peptide levels upon treatment with bortezomib and other inhibitors is the result of allosteric effects of these compounds on the proteasome. Because intracellular peptides are likely to be functional, it is possible that some of the physiologic effects of bortezomib and carfilzomib arise from the perturbation of peptide levels inside the cell.

  3. Alteration of blood glucose levels in the rat following exposure to hyperbaric oxygen.

    Science.gov (United States)

    Eynan, Mirit; Mullokandov, Michael; Krinsky, Nitzan; Biram, Adi; Arieli, Yehuda

    2015-09-01

    Findings regarding blood glucose level (BGL) on exposure to hyperbaric oxygen (HBO) are contradictory. We investigated the influence of HBO on BGL, and of BGL on latency to central nervous system oxygen toxicity (CNS-OT). The study was conducted on five groups of rats: Group 1, exposure to oxygen at 2.5 atmospheres absolute (ATA), 90 min/day for 7 days; Group 2, exposure to oxygen once a week from 2 to 6 ATA in increments of 1 ATA/wk, for a period of time calculated as 60% of the latency to CNS-OT (no convulsions); Group 3, exposure to 6 ATA breathing a gas mixture with a pO2 of 0.21; Group 4, received 10 U/kg insulin to induce hypoglycemia before exposure to HBO; Group 5, received 33% glucose to induce hyperglycemia before exposure to HBO. Blood samples were drawn before and after exposures for measurement of BGL. No change was observed in BGL after exposure to oxygen at 2.5 ATA, 90 min/day for 7 days. BGL was significantly elevated after exposure to oxygen at 6 ATA until the appearance of convulsions, and following exposure to 4, 5, and 6 ATA without convulsions (P HBO exposure on elevation of BGL, starting at 4 ATA. This implies that BGL may serve as a marker for the generation of CNS-OT. PMID:26183474

  4. Role of proline and GABA in sexual reproduction of angiosperms

    OpenAIRE

    Biancucci, Marco; Mattioli, Roberto; Forlani, Giuseppe; Funck, Dietmar; Costantino, Paolo; Trovato, Maurizio

    2015-01-01

    Two glutamate derivatives, proline and γ-aminobutyric acid (GABA), appear to play pivotal roles in different aspects of sexual reproduction in angiosperms, although their precise function in plant reproduction and the molecular basis of their action are not yet fully understood. Proline and GABA have long been regarded as pivotal amino acids in pollen vitality and fertility. Proline may constitute up to 70% of the free amino acid pool in pollen grains and it has been recently shown that Arabi...

  5. GABA receptors modulate trigeminovascular nociceptive neurotransmission in the trigeminocervical complex

    OpenAIRE

    Storer, R James; Akerman, Simon; Goadsby, Peter J.

    2001-01-01

    GABA (γ-aminobutyric acid) receptors involved in craniovascular nociceptive pathways were characterised by in vivo microiontophoresis of GABA receptor agonists and antagonists onto neurones in the trigeminocervical complex of the cat.Extracellular recordings were made from neurones in the trigeminocervical complex activated by supramaximal electrical stimulation of superior sagittal sinus, which were subsequently stimulated with L-glutamate.Cell firing evoked by microiontophoretic application...

  6. Phenotypic diversity and altered environmental plasticity in Arabidopsis thaliana with reduced Hsp90 levels.

    Directory of Open Access Journals (Sweden)

    Todd A Sangster

    Full Text Available The molecular chaperone HSP90 aids the maturation of a diverse but select set of metastable protein clients, many of which are key to a variety of signal transduction pathways. HSP90 function has been best investigated in animal and fungal systems, where inhibition of the chaperone has exceptionally diverse effects, ranging from reversing oncogenic transformation to preventing the acquisition of drug resistance. Inhibition of HSP90 in the model plant Arabidopsis thaliana uncovers novel morphologies dependent on normally cryptic genetic variation and increases stochastic variation inherent to developmental processes. The biochemical activity of HSP90 is strictly conserved between animals and plants. However, the substrates and pathways dependent on HSP90 in plants are poorly understood. Progress has been impeded by the necessity of reliance on light-sensitive HSP90 inhibitors due to redundancy in the A. thaliana HSP90 gene family. Here we present phenotypic and genome-wide expression analyses of A. thaliana with constitutively reduced HSP90 levels achieved by RNAi targeting. HSP90 reduction affects a variety of quantitative life-history traits, including flowering time and total seed set, increases morphological diversity, and decreases the developmental stability of repeated characters. Several morphologies are synergistically affected by HSP90 and growth temperature. Genome-wide expression analyses also suggest a central role for HSP90 in the genesis and maintenance of plastic responses. The expression results are substantiated by examination of the response of HSP90-reduced plants to attack by caterpillars of the generalist herbivore Trichoplusia ni. HSP90 reduction potentiates a more robust herbivore defense response. In sum, we propose that HSP90 exerts global effects on the environmental responsiveness of plants to many different stimuli. The comprehensive set of HSP90-reduced lines described here is a vital instrument to further examine

  7. Altered Brain Network in Amyotrophic Lateral Sclerosis: A Resting Graph Theory-Based Network Study at Voxel-Wise Level

    Science.gov (United States)

    Zhou, Chaoyang; Hu, Xiaofei; Hu, Jun; Liang, Minglong; Yin, Xuntao; Chen, Lin; Zhang, Jiuquan; Wang, Jian

    2016-01-01

    Amyotrophic lateral sclerosis (ALS) is a rare degenerative disorder characterized by loss of upper and lower motor neurons. Neuroimaging has provided noticeable evidence that ALS is a complex disease, and shown that anatomical and functional lesions extend beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. The aim of this study is to investigate graph theory-based functional network abnormalities at voxel-wise level in ALS patients on a whole brain scale. Forty-three ALS patients and 44 age- and sex-matched healthy volunteers were enrolled. The voxel-wise network degree centrality (DC), a commonly employed graph-based measure of network organization, was used to characterize the alteration of whole brain functional network. Compared with the controls, the ALS patients showed significant increase of DC in the left cerebellum posterior lobes, bilateral cerebellum crus, bilateral occipital poles, right orbital frontal lobe, and bilateral prefrontal lobes; significant decrease of DC in the bilateral primary motor cortex, bilateral sensory motor region, right prefrontal lobe, left bilateral precuneus, bilateral lateral temporal lobes, left cingulate cortex, and bilateral visual processing cortex. The DC's z-scores of right inferior occipital gyrus were significant negative correlated with the ALSFRS-r scores. Our findings confirm that the regions with abnormal network DC in ALS patients were located in multiple brain regions including primary motor, somatosensory and extra-motor areas, supporting the concept that ALS is a multisystem disorder. Specifically, our study found that DC in the visual areas was altered and ALS patients with higher DC in right inferior occipital gyrus have more severity of disease. The result demonstrated that the altered DC value in this region can probably be used to assess severity of ALS. PMID:27242409

  8. Control of cortical neuronal migration by glutamate and GABA.

    Science.gov (United States)

    Luhmann, Heiko J; Fukuda, A; Kilb, W

    2015-01-01

    Neuronal migration in the cortex is controlled by the paracrine action of the classical neurotransmitters glutamate and GABA. Glutamate controls radial migration of pyramidal neurons by acting primarily on NMDA receptors and regulates tangential migration of inhibitory interneurons by activating non-NMDA and NMDA receptors. GABA, acting on ionotropic GABAA-rho and GABAA receptors, has a dichotomic action on radially migrating neurons by acting as a GO signal in lower layers and as a STOP signal in upper cortical plate (CP), respectively. Metabotropic GABAB receptors promote radial migration into the CP and tangential migration of interneurons. Besides GABA, the endogenous GABAergic agonist taurine is a relevant agonist controlling radial migration. To a smaller extent glycine receptor activation can also influence radial and tangential migration. Activation of glutamate and GABA receptors causes increases in intracellular Ca(2+) transients, which promote neuronal migration by acting on the cytoskeleton. Pharmacological or genetic manipulation of glutamate or GABA receptors during early corticogenesis induce heterotopic cell clusters in upper layers and loss of cortical lamination, i.e., neuronal migration disorders which can be associated with neurological or neuropsychiatric diseases. The pivotal role of NMDA and ionotropic GABA receptors in cortical neuronal migration is of major clinical relevance, since a number of drugs acting on these receptors (e.g., anti-epileptics, anesthetics, alcohol) may disturb the normal migration pattern when present during early corticogenesis. PMID:25688185

  9. Control of cortical neuronal migration by glutamate and GABA

    Directory of Open Access Journals (Sweden)

    Heiko J Luhmann

    2015-01-01

    Full Text Available Neuronal migration in the cortex is controlled by the paracrine action of the classical neurotransmitters glutamate and GABA. Glutamate controls radial migration of pyramidal neurons by acting primarily on NMDA receptors and regulates tangential migration of inhibitory interneurons by activating non-NMDA and NMDA receptors. GABA, acting on ionotropic GABAA-rho and GABAA receptors, has a dichotomic action on radially migrating neurons by acting as a GO signal in lower layers and as a STOP signal in upper cortical plate (CP, respectively. Metabotropic GABAB receptors promote radial migration into the CP and tangential migration of interneurons. Besides GABA, the endogenous GABAergic agonist taurine is a relevant agonist controlling radial migration. To a smaller extent glycine receptor activation can also influence radial and tangential migration. Activation of glutamate and GABA receptors causes increases in intracellular Ca2+ transients, which promote neuronal migration by acting on the cytoskeleton. Pharmacological or genetic manipulation of glutamate or GABA receptors during early corticogenesis induce heterotopic cell clusters in upper layers and loss of cortical lamination, i.e. neuronal migration disorders which can be associated with neurological or neuropsychiatric diseases. The pivotal role of NMDA and ionotropic GABA receptors in cortical neuronal migration is of major clinical relevance, since a number of drugs acting on these receptors (e.g. anti-epileptics, anesthetics, alcohol may disturb the normal migration pattern when present during early corticogenesis.

  10. Altered Levels of Aroma and Volatiles by Metabolic Engineering of Shikimate Pathway Genes in Tomato Fruits

    Directory of Open Access Journals (Sweden)

    Vered Tzin

    2015-06-01

    Full Text Available The tomato (Solanum lycopersicum fruit is an excellent source of antioxidants, dietary fibers, minerals and vitamins and therefore has been referred to as a “functional food”. Ripe tomato fruits produce a large number of specialized metabolites including volatile organic compounds. These volatiles serve as key components of the tomato fruit flavor, participate in plant pathogen and herbivore defense, and are used to attract seed dispersers. A major class of specialized metabolites is derived from the shikimate pathway followed by aromatic amino acid biosynthesis of phenylalanine, tyrosine and tryptophan. We attempted to modify tomato fruit flavor by overexpressing key regulatory genes in the shikimate pathway. Bacterial genes encoding feedback-insensitive variants of 3-Deoxy-D-Arabino-Heptulosonate 7-Phosphate Synthase (DAHPS; AroG209-9 and bi-functional Chorismate Mutase/Prephenate Dehydratase (CM/PDT; PheA12 were expressed under the control of a fruit-specific promoter. We crossed these transgenes to generate tomato plants expressing both the AroG209 and PheA12 genes. Overexpression of the AroG209-9 gene had a dramatic effect on the overall metabolic profile of the fruit, including enhanced levels of multiple volatile and non-volatile metabolites. In contrast, the PheA12 overexpression line exhibited minor metabolic effects compared to the wild type fruit. Co-expression of both the AroG209-9 and PheA12 genes in tomato resulted overall in a similar metabolic effect to that of expressing only the AroG209-9 gene. However, the aroma ranking attributes of the tomato fruits from PheA12//AroG209-9 were unique and different from those of the lines expressing a single gene, suggesting a contribution of the PheA12 gene to the overall metabolic profile. We suggest that expression of bacterial genes encoding feedback-insensitive enzymes of the shikimate pathway in tomato fruits provides a useful metabolic engineering tool for the modification of

  11. (Alpha, gamma) irradiation effect on the alteration of high-level radioactive wastes matrices (UO2, hollandite, glass SON68)

    International Nuclear Information System (INIS)

    The aim of this work is to determine the effect of irradiation on the alteration of high level nuclear waste forms matrices. The matrices investigated are UO2 to simulate the spent fuel, the hollandite for the specific conditioning of Cs, and the inactive glass SON68 representing the nuclear glass R7T7) The alpha irradiation experiments on UO2 colloids in aqueous carbonate media have enabled to distinguish between the oxidation of UO2 matrix as initial and dissolution as subsequent step. The simultaneous presence of carbonate and H2O2 (product resulting from water radiolysis) increased the dissolution rate of UO2 to its maximum value governed by the oxidation rate. ii) The study of hollandite alteration under gamma irradiation confirmed the good retention capacity for Cs and Ba. Gamma irradiation had brought only a little influence on releasing of Cs and Ba in solution. Electronic irradiation had conducted to the amorphization of the hollandite only for a dose 1000 times higher than the auto-induced dose of Ba over millions of years. iii) The experiences of glass irradiation under alpha beam and of helium implantation in the glass SON68 were analyzed by positon annihilation spectroscopy. No effect has been observed on the solid surface for an irradiation dose equal to 1000 years of storage. (author)

  12. Association of urinary metal profiles with altered glucose levels and diabetes risk: a population-based study in China.

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    Wei Feng

    Full Text Available Elevated heavy metals and fasting plasma glucose (FPG levels were both associated with increased risk of cardiovascular diseases. However, studies on the associations of heavy metals and essential elements with altered FPG and diabetes risk were limited or conflicting. The objective of this study was to evaluate the potential associations of heavy metals and essential trace elements with FPG and diabetes risk among general Chinese population.We conducted a cross-sectional study to investigate the associations of urinary concentrations of 23 metals with FPG, impaired fasting glucose (IFG and diabetes among 2242 community-based Chinese adults in Wuhan. We used the false discovery rate (FDR method to correct for multiple hypothesis tests.After adjusting for potential confounders, urinary aluminum, titanium, cobalt, nickel, copper, zinc, selenium, rubidium, strontium, molybdenum, cadmium, antimony, barium, tungsten and lead were associated with altered FPG, IFG or diabetes risk (all P< 0.05; arsenic was only dose-dependently related to diabetes (P< 0.05. After additional adjustment for multiple testing, titanium, copper, zinc, selenium, rubidium, tungsten and lead were still significantly associated with one or more outcomes (all FDR-adjusted P< 0.05.Our results suggest that multiple metals in urine are associated with FPG, IFG or diabetes risk. Because the cross-sectional design precludes inferences about causality, further prospective studies are warranted to validate our findings.

  13. Drospirenone intake alters plasmatic steroid levels and cyp17a1 expression in gonads of juvenile sea bass.

    Science.gov (United States)

    Blanco, Maria; Fernandes, Denise; Medina, Paula; Blázquez, Mercedes; Porte, Cinta

    2016-06-01

    Drospirenone (DRO) is one of the most widely used progestins in contraceptive treatments and hormone replacement therapies. The pharmacokinetics and potential toxicological effects of DRO were investigated in juvenile sea bass (Dicentrarchus labrax) exposed through the diet (0.01-10 μg DRO/g) for up to 31 days. DRO was detected in the blood (4-27 ng/mL) of fish exposed to the highest concentration, with no significant bioaccumulation over time and no alteration of hepatic metabolizing enzymes, namely, CYP1A and CYP3A-catalysed activities and UDP-glucuronyltransferase (UGT). Pregnenolone (P5), progesterone (P4), 17α-hydroxyprogesterone (17P4), 17α-hydroxypregnenolone (17P5), androstenedione (AD) and testosterone (T) were determined in plasma and gene expression of cyp17a1, cyp19a1a and cyp11β analysed by qRT-PCR in gonads. The significant increase in plasmatic levels of 17P5, 17P4 and AD detected after 31 days exposure to 10 ng DRO/g together with the increased expression of cyp17a1 in females evidence the ability of DRO to alter steroid synthesis at low intake concentrations (7 ng DRO/day). However, the potential consequences of this steroid shift for female reproduction remain to be investigated. PMID:26995450

  14. The GABA excitatory/inhibitory developmental sequence: a personal journey.

    Science.gov (United States)

    Ben-Ari, Y

    2014-10-24

    The developing brain is talkative but its language is not that of the adult. Most if not all voltage and transmitter-gated ionic currents follow a developmental sequence and network-driven patterns differ in immature and adult brains. This is best illustrated in studies engaged almost three decades ago in which we observed elevated intracellular chloride (Cl(-))i levels and excitatory GABA early during development and a perinatal excitatory/inhibitory shift. This sequence is observed in a wide range of brain structures and animal species suggesting that it has been conserved throughout evolution. It is mediated primarily by a developmentally regulated expression of the NKCC1 and KCC2 chloride importer and exporter respectively. The GABAergic depolarization acts in synergy with N-methyl-d-aspartate (NMDA) receptor-mediated and voltage-gated calcium currents to enhance intracellular calcium exerting trophic effects on neuritic growth, migration and synapse formation. These sequences can be deviated in utero by genetic or environmental insults leading to a persistence of immature features in the adult brain. This "neuroarcheology" concept paves the way to novel therapeutic perspectives based on the use of drugs that block immature but not adult currents. This is illustrated notably with the return to immature high levels of chloride and excitatory actions of GABA observed in many pathological conditions. This is due to the fact that in the immature brain a down regulation of KCC2 and an up regulation of NKCC1 are seen. Here, I present a personal history of how an unexpected observation led to novel concepts in developmental neurobiology and putative treatments of autism and other developmental disorders. Being a personal account, this review is neither exhaustive nor provides an update of this topic with all the studies that have contributed to this evolution. We all rely on previous inventors to allow science to advance. Here, I present a personal summary of this

  15. Motor dysfunction in cerebellar Purkinje cell-specific vesicular GABA transporter knockout mice

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    Mikiko eKayakabe

    2014-01-01

    Full Text Available γ-Aminobutyric acid (GABA is a major inhibitory neurotransmitter in the adult mammalian central nervous system and plays modulatory roles in neural development. The vesicular GABA transporter (VGAT is an essential molecule for GABAergic neurotransmission due to its role in vesicular GABA release. Cerebellar Purkinje cells (PCs are GABAergic projection neurons that are indispensable for cerebellar function. To elucidate the significance of VGAT in cerebellar PCs, we generated and characterized PC-specific VGAT knockout (L7-VGAT mice. VGAT mRNAs and proteins were specifically absent in the 40-week-old L7-VGAT PCs. The morphological charactereistics, such as lamination and foliation of the cerebellar cortex, of the L7-VGAT mice were similar to those of the control littermate mice. Moreover, the protein expression levels and patterns of pre- (calbindin and parvalbumin and postsynaptic (GABA-A receptor α1 subunit (GABAARα1 and gephyrin molecules between the L7-VGAT and control mice were similar in the deep cerebellar nuclei that receive PC projections. However, the L7-VGAT mice performed poorly in the accelerating rotarod test and displayed ataxic gait in the footprint test. The L7-VGAT mice also exhibited severer ataxia as VGAT deficits progressed. These results suggest that VGAT in cerebellar Purkinje cells is not essential for the rough maintenance of cerebellar structure, but does play an important role in motor coordination. The L7-VGAT mice are a novel model of ataxia without PC degeneration, and would also be useful for studying the role of Purkinje cells in cognition and emotion.

  16. CXCL12 chemokine and GABA neurotransmitter systems crosstalk and their putative roles

    Directory of Open Access Journals (Sweden)

    Guyon eAlice

    2014-04-01

    Full Text Available Since CXCL12 and its receptors, CXCR4 and CXCR7, have been found in the brain, the role of this chemokine has been expanded from chemoattractant in the immune system to neuromodulatory in the brain. Several pieces of evidence suggest that this chemokine system could crosstalk with the GABAergic system, known to be the main inhibitory neurotransmitter system in the brain. Indeed, GABA and CXCL12 as well as their receptors are colocalized in many cell types including neurons and there are several examples in which these two systems interact. Several mechanisms can be proposed to explain how these systems interact, including receptor-receptor interactions, crosstalk at the level of second messenger cascades, or direct pharmacological interactions, as GABA and GABAB receptor agonists/antagonists have been shown to be allosteric modulators of CXCR4.The interplay between CXCL12/CXCR4-CXCR7 and GABA/GABAA-GABAB receptors systems could have many physiological implications in neurotransmission, cancer and inflammation. In addition, the GABAB agonist baclofen is currently used in medicine to treat spasticity in patients with spinal cord injury, cerebral palsy, traumatic brain injury, multiple sclerosis and other disorders. More recently it has also been used in the treatment of alcohol dependence and withdrawal. The allosteric effects of this agent on CXCR4 could contribute to these beneficial effects or at the opposite, to its side effects.

  17. Abuse Potential of Soma: the GABA(A) Receptor as a Target.

    Science.gov (United States)

    Gonzalez, Lorie A; Gatch, Michael B; Forster, Michael J; Dillon, Glenn H

    2009-01-01

    Soma(®) (carisoprodol) is an increasingly abused, centrally-acting muscle relaxant. Despite the prevalence of carisoprodol abuse, its mechanism of action remains unclear. Its sedative effects, which contribute to its therapeutic and recreational use, are generally attributed to the actions of its primary metabolite, meprobamate, at GABA(A) receptors (GABA(A)R). Meprobamate is a controlled substance at the federal level; ironically, carisoprodol is not currently classified as such. Using behavioral and molecular pharmacological approaches, we recently demonstrated carisoprodol, itself, is capable of modulating GABA(A)R function in a manner similar to central nervous system depressants. Its functional similarities with this highly addictive class of drugs may contribute to the abuse potential of carisoprodol. The site of action of carisoprodol has not been identified; based on our studies, interaction with benzodiazepine or barbiturate sites is unlikely. These recent findings, when coupled with numerous reports in the literature, support the contention that the non-controlled status of carisoprodol should be reevaluated. PMID:20419052

  18. Localisation of 3H-GABA in the rat olfactory bulb: An in vivo and in vitro autoradiographic study

    International Nuclear Information System (INIS)

    In an attempt to further clarify the localisation of GABAergic elements in the olfactory bulb we have performed, in vivo and in vitro, autoradiographic studies with 3H-GABA (#betta#-amino butyric acid) and 3H-DABA (L-2,4 diamino butyric acid). The results have shown a strong labelling with 3H-GABA of the glial cells in all the layers of the olfactory bulb. A high concentration of grains was observed in the periglomerular region. The labelling in the external plexiform layer was uniformly distributed in the neuropile with the strongest activity at the level of the dendritic processes of the granule cells, leaving the mitral cell dendrites and cell bodies almost free of grains. 3H-DABA showed a very similar pattern to 3H-GABA. When olfactory bulb slices were preincubated with #betta#-alanine the labelling of the glial elements almost disappeared especially at the level of the olfactory nerve layer. The labelling pattern of the other layers of the bulb remained mostly unchanged. This supports the view that a population of periglomerular and granule cells are GABAergic and that #betta#-alanine competes with GABA uptake sites only in glial cells. (orig.)

  19. Decreased GABA(A) benzodiazepine binding site densities in postmortem brains of Cloninger type 1 and 2 alcoholics.

    Science.gov (United States)

    Laukkanen, Virpi; Storvik, Markus; Häkkinen, Merja; Akamine, Yumiko; Tupala, Erkki; Virkkunen, Matti; Tiihonen, Jari

    2013-03-01

    Ethanol modulates the GABA(A) receptor to cause sedative, anxiolytic and hypnotic effects that are qualitatively similar to benzodiazepines and barbiturates. The aim of this study was to explore if GABA(A) receptor density is altered in post-mortem brains of anxiety-prone Cloninger type 1 and socially hostile type 2 alcoholic subtypes when compared to controls. The GABA(A) binding site density was measured by whole-hemisphere autoradiography with tritium labeled flunitrazepam ([(3)H]flunitrazepam) from 17 alcoholic (nine type 1, eight type 2) and 10 non-alcoholic post-mortem brains, using cold flumazepam as a competitive ligand. A total of eight specific brain areas were examined. Alcoholics displayed a significantly (p < 0.001, bootstrap type generalizing estimating equations model) reduced [(3)H]flunitrazepam binding site density when compared to controls. When localized, type 2 alcoholics displayed a significantly (p ≤ 0.05) reduced [(3)H]flunitrazepam binding site density in the internal globus pallidus, the gyrus dentatus and the hippocampus, whereas type 1 alcoholics differed from controls in the internal globus pallidus and the hippocampus. While previous reports have demonstrated significant alterations in dopaminergic and serotonergic receptors between type 1 and type 2 alcoholics among these same subjects, we observed no statistically significant difference in [(3)H]flunitrazepam binding site densities between the Cloninger type 1 and type 2 alcoholics. PMID:23332316

  20. 大鼠生后MGBv神经元主动膜特性的变化及GABA受体激动剂的影响%Alteration of membrane properties of MGBv neurons and the effect of GABA receptor agonist on them during postnatal development in rats

    Institute of Scientific and Technical Information of China (English)

    姚小红; 万子兵; 熊鹰

    2005-01-01

    Objective To observe membrane properties of ventral partition of the medial geniculate body (MGBv) in Wistar rat and the effect of GABA receptor agonist on them during postnatal development. Methods Whole-cell patch clamp recording was used to record waveform of action potential (AP) and the effect of GABA receptor agonist on them from neurons in the MGBv of rats ( postnatal days 3-30). Results There was a difference in AP firing pattern in rat MGBv neurons of different postnatal day. We only recorded low threshold Ca2+ spikes (LTS) in P3 MGBv neurons, but recorded AP in P6-30 MGBv neurons after depolarizing currents application; AP was recorded at the start phase of pulse and with a long-last after hyperpolarization potential (AHP) in P8, in P20 AP was recorded after a delay and it appeared on depolarizing ramp with a shorter-last AHP compared with P8. The GABAA receptor agonist, muscimol, and the GABAB receptor agonist, baclofen, had effects on responses evoked by depolarizing current in the MGBv neurons in P6 and P15 rats. Muscimol and baclofen reduced AP firing rather than AP amplitude in P6 MGBv neurons, however, in P15 MGBv neurons baclofen had little effect on AP firing while muscimol greatly reduced the size of voltage shift produced by positive or negative current injection. Conclusion The AP waveform of MGBv neurons matures rapidly during first two postnatal weeks. A similar rapid maturation also has been observed in rat neocortical and hippocampal pyramidal neurons as well as in ferret dorsal lateral geniculate nucleus (LGNd) neurons. These results suggest that in the central nervous system of small mammals, AP waveforms mature rapidly in many types of neurons, thus, coordinated activities in neuronal circuits may occur. In early postnatal development, GABA receptor mainly mediates an excitation effect, depolarizes P6 MGBv neurons and dramatically increases the frequency of AP firing. Inhibition of GABA receptor matures slowly along with increment of

  1. Alteration of Na,K-ATPase subunit mRNA and protein levels in hypertrophied rat heart.

    Science.gov (United States)

    Charlemagne, D; Orlowski, J; Oliviero, P; Rannou, F; Sainte Beuve, C; Swynghedauw, B; Lane, L K

    1994-01-14

    To determine if an altered expression of the Na,K-ATPase alpha isoform genes is responsible for an observed increase in cardiac glycoside sensitivity in compensatory hypertrophy, we performed Northern and slot blot analyses of RNA and specific immunological detection of Na,K-ATPase isoforms in rat hearts from normal and pressure overload-treated animals induced by abdominal aortic constriction. During the early phase of hypertrophy, the only alteration is a decrease in the alpha 2 mRNA isoform. In the compensated hypertrophied heart, the levels of the predominant alpha 1 isoform (mRNA and protein) and the beta 1 subunit mRNA are unchanged. In contrast, the alpha 2 isoform (mRNA and protein) is decreased by 35% and up to 61-64% in mild ( 55%) hypertrophy, respectively. The alpha 3 isoform (mRNA and protein), which is extremely low in adult heart, is increased up to 2-fold during hypertrophy but accounts for only approximately equal to 5% of the total alpha isoform mRNA. These findings demonstrate that, in cardiac hypertrophy, the three alpha isoforms of the Na,K-ATPase are independently regulated and that regulation occurs at a pretranslational level. The pattern of expression in hypertrophied adult heart is similar to that of the neonatal heart where the inverse regulation between the alpha 2 and alpha 3 ouabain high affinity isoforms has been reported. This suggests that distinct regulatory mechanisms controlling Na,K-ATPase isoform expression may, at least in part, be involved in the sensitivity to cardiac glycosides. PMID:8288620

  2. Spinal Fluid Lactate Dehydrogenase Level Differentiates between Structural and Metabolic Etiologies of Altered Mental Status in Children

    Directory of Open Access Journals (Sweden)

    Nahid KHOSROSHAHI

    2015-01-01

    Full Text Available How to Cite This Article: Khosroshahi N, Alizadeh P, Khosravi M, Salamati P, Kamrani K. Spinal Fluid Lactate Dehydrogenase Level Differentiates between Structural and Metabolic Etiologies of Altered Mental Status in Children. Iran J Child Neurol. 2015 Winter;9(1:31-36.AbstractObjectiveAltered mental status is a common cause of intensive care unit admission inchildren. Differentiating structural causes of altered mental status from metabolic etiologies is of utmost importance in diagnostic approach and management of the patients. Among many biomarkers proposed to help stratifying patients with altered mental status, spinal fluid lactate dehydrogenase appears to be the most promising biomarker to predict cellular necrosis.Materials & MethodsIn this cross sectional study we measured spinal fluid level of lactatedehydrogenase in children 2 months to 12 years of age admitted to a single center intensive care unit over one year. Spinal fluid level of lactate dehydrogenase in 40 pediatric cases of febrile seizure was also determined as the control group.ResultsThe study group included 35 boys (58.3% and 25 girls (41.7%. Their meanage was 2.7+/-3 years and their mean spinal fluid lactate dehydrogenase levelwas 613.8+/-190.4 units/liter. The control group included 24 boys (55.8% and19 girls (44.2%. Their mean age was 1.3+/-1.2 years and their mean spinalfluid lactate dehydrogenase level was 18.9+/-7.5 units/liter. The mean spinalfluid lactate dehydrogenase level in children with abnormal head CT scan was246.3+/-351.5 units/liter compared to 164.5+/-705.7 in those with normal CTscan of the head (p=0.001.ConclusionSpinal fluid lactate dehydrogenase level is useful in differentiating structural andmetabolic causes of altered mental status in children. ReferencesFesk SK. Coma and confusional states: emergency diagnosis and management. Neurol Clin 1998; 16: 237- 56.Cucchiara BL, Kanser SE, Wolk DA, et al. Early impairment in consciousness Predicts

  3. Anti-inflammatory Montelukast prevents toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin: Oxidative stress, histological alterations in liver, and serum cytokine levels.

    Science.gov (United States)

    Bentli, Recep; Ciftci, Osman; Cetin, Asli; Otlu, Ali

    2016-05-01

    This study aimed to investigate the potential beneficial effects of the montelukast (ML) on oxidative stress and histological alterations in liver tissues and cytokine levels in rats intoxicated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were divided randomly into four equal groups (control, TCDD, ML, TCDD + ML). TCDD were administered by gavages dissolved in corn oil at the doses of 2 µg/kg/week, and ML was given intraperitoneally at the dose of 10 mg/kg/day. Oxidative status, histological alterations, and cytokine levels were analyzed on day 60. The results showed that although TCDD induced oxidative stress via significant increase in formation of thiobarbituric acid reactive substance, it caused a significant decline in glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) levels in liver. Besides, TCDD led to significant histopathological damage in liver and serum cytokine levels alterations (increase in tumor necrosis factor α and interleukin 1β levels). In contrast, ML treatment reversed oxidative effects of TCDD by increasing the levels of GSH, CAT, and SOD and decreasing the formation of TBARS. Also, it can normalize the levels of histological and cytokine alterations induced by TCDD. In conclusion, it was determined that TCDD exposure caused adverse effects on cytokine levels, histological alterations, and oxidative stress in rats. However, ML treatment partially eliminated toxic effects of TCDD. Thus, it was judged that coadministration of ML with TCDD may be useful to attenuate the negative effects of TCDD. PMID:24215062

  4. Expression of the GABA(A) receptor alpha6 subunit in cultured cerebellar granule cells is developmentally regulated by activation of GABA(A) receptors

    DEFF Research Database (Denmark)

    Carlson, B X; Belhage, B; Hansen, G H;

    1997-01-01

    Primary cultures of cerebellar granule cells, prepared from cerebella of 7-day-old rats and cultured for 4 or 8 days, were used to study the neurodifferentiative effect of a GABA(A) receptor agonist, 4,5,6,7-tetrahydroisoxazol[5,4-c]pyridin-3-ol (THIP), on the expression of the alpha6 GABA...... suggest that THIP has a trophic effect on alpha6 subunit expression, and this effect occurs only at an early developmental stage. Moreover, this study presents further evidence for the role of GABA(A) agonists, and thus the neurotransmitter, GABA, in regulating the expression of GABA(A) receptor subunits...

  5. GABA agonist induced changes in ultrastructure and GABA receptor expression in cerebellar granule cells is linked to hyperpolarization of the neurons

    DEFF Research Database (Denmark)

    Belhage, B; Hansen, Gert Helge; Schousboe, A

    1990-01-01

    GABA has been shown to exert a neurotrophic like activity by enhancing the morphological and functional maturation of neurons. Mechanisms involved in this effect of GABA are largely unknown but since GABA has been shown to mediate a hyperpolarizing action on neurons it can be assumed that this...... action might be important. In order to investigate this possibility, the ability to mimic the trophic actions of GABA of different agents known to influence the membrane potential or the GABA gated chloride channels was studied. Hence, GABA receptor expression as well as the ultrastructure of cerebellar...... granule cells were monitored after exposure of the cells in culture to either bromide, valinomycin or picrotoxin. It was found that cells which at early developmental stages (4 days in culture) were exposed to bromide or valinomycin expressed low affinity GABA receptors similar to cells treated with the...

  6. Pharmacological characterization of homobaclofen on wild type and mutant GABA(B)1b receptors coexpressed with the GABA(B)2 receptor

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Madsen, Bo E.; Krogsgaard-Larsen, P;

    2001-01-01

    Homobaclofen (5-amino-3-(4-chlorophenyl) pentanoic acid) is a homologue of the classical GABA(B) receptor agonist baclofen. In a recent study, the two enantiomers of this compound were tested in a GABA(B) receptor selective [3H]gamma-aminobutyric acid ([3H]GABA) binding assay using rat brain...... rat GABA(B)1b receptors coexpressed with rat GABA(B)2 receptors. The results from this study correlate nicely with the binding data from rat brain. (R)-Homobaclofen was shown to act like (R)-baclofen albeit with 20-fold less potency, and (S)-homobaclofen was inactive on the receptor. The discrepancies...... between the data obtained in this study and those from the guinea pig ileum model could be ascribed to differences in amino acid sequence or receptor splicing of GABA(B) receptors between the two species. Another explanation for the observation is the possible existence of a novel yet uncloned GABA...

  7. [Influence of GABA(C)-Receptor Antagonist on Formation of Evoked Potentials in Columns of the Rat Somatosensory Cortex].

    Science.gov (United States)

    Matukhno, A E; Lysenko, L V; Andreeva, Y V; Sukhov, A G

    2015-01-01

    Microelectrode studies of evoked potentials (EP) in neuronal column of rats barrel cortex show activating action of selective GABA(C)-receptor antagonist 1,2,5,6-tetrahydropyridin-4-yl-methylphosphinic acid (TPMPA) mainly on secondary components of EP of supragranular afferent layers of column compared to the efferent infragranular layers. These data suggest localization of GABA(C)-receptors on pre- synaptic terminals of thalamo-cortical glutamatergic afferents and ascending apical dendrites of pyramidal cells. A blockade of GABA(C)-receptors with the selective antagonist TPM PA leads to dose-dependent afferent depolarization with development of presynaptic inhibition and suppression of primary components of EP GABA(C)-receptors blocker produces different effects on secondary components of EP in supragranular layers of the cortex caused by the development of neuronal after hyperpolarization followed by high-amplitude primary response and afterdepolarization followed by low-amplitude primary responses with subsequent activation of different voltage-gated channels and formation of different level of cortical direct current potential gradients. PMID:26841661

  8. Propofol, but not etomidate, increases corticosterone levels and induces long-term alteration in hippocampal synaptic activity in neonatal rats.

    Science.gov (United States)

    Xu, Changqing; Seubert, Christoph N; Gravenstein, Nikolaus; Martynyuk, Anatoly E

    2016-04-01

    Animal studies provide strong evidence that general anesthetics (GAs), administered during the early postnatal period, induce long-term cognitive and neurological abnormalities. Because the brain growth spurt in rodents is delayed compared to that in humans, a fundamental question is whether the postnatal human brain is similarly vulnerable. Sevoflurane and propofol, GAs that share positive modulation of the gamma-aminobutyric acid type A receptor (GABAAR) function cause marked increase in corticosterone levels and induce long-term developmental alterations in synaptic activity in rodents. If synaptogenesis is affected, investigation of mechanisms of the synaptic effects of GAs is of high interest because synaptogenesis in humans continues for several years after birth. Here, we compared long-term synaptic effects of etomidate with those of propofol. Etomidate and propofol both positively modulate GABAAR activity, but in contrast to propofol, etomidate inhibits the adrenal synthesis of corticosterone. Postnatal day (P) 4, 5, or 6 rats received five injections of etomidate, propofol, or vehicle control during 5h of maternal separation. Endocrine effects of the anesthetics were evaluated by measuring serum levels of corticosterone immediately after anesthesia or maternal separation. The frequency and amplitude of miniature inhibitory postsynaptic currents (mIPSCs) in hippocampal CA1 pyramidal neurons were measured at P24-40 and P≥80. Only propofol caused a significant increase in serum corticosterone levels (F(4.26)=17.739, P<0.001). In contrast to increased frequency of mIPSCs in the propofol group (F(4.23)=8.731, p<0.001), mIPSC activity in the etomidate group was not different from that in the vehicle groups. The results of this study together with previously published data suggest that anesthetic-caused increase in corticosterone levels is required for GABAergic GAs to induce synaptic effects in the form of a long-term increase in the frequency of hippocampal m

  9. ToF-SIMS imaging of molecular-level alteration mechanisms in Le Bonheur de vivre by Henri Matisse

    Energy Technology Data Exchange (ETDEWEB)

    Voras, Zachary E.; Wiggins, Marcie B.; Beebe, Thomas P. [University of Delaware, Department of Chemistry and Biochemistry, Newark, DE (United States); University of Delaware, UD Surface Analysis Facility, Newark, DE (United States); DeGhetaldi, Kristin [University of Delaware, Department of Art Conservation, Newark, DE (United States); Winterthur-University of Delaware Program in Art Conservation, Winterthur, DE (United States); Buckley, Barbara [The Barnes Foundation, Department of Conservation, Philadelphia, PA (United States); Baade, Brian [University of Delaware, Department of Art Conservation, Newark, DE (United States); Mass, Jennifer L. [Winterthur Museum, Scientific Research and Analysis Laboratory, Conservation Department, Winterthur, DE (United States)

    2015-11-15

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has recently been shown to be a valuable tool for cultural heritage studies, especially when used in conjunction with established analytical techniques in the field. The ability of ToF-SIMS to simultaneously image inorganic and organic species within a paint cross section at micrometer-level spatial resolution makes it a uniquely qualified analytical technique to aid in further understanding the processes of pigment and binder alteration, as well as pigment-binder interactions. In this study, ToF-SIMS was used to detect and image both molecular and elemental species related to CdS pigment and binding medium alteration on the painting Le Bonheur de vivre (1905-1906, The Barnes Foundation) by Henri Matisse. Three categories of inorganic and organic components were found throughout Le Bonheur de vivre and co-localized in cross-sectional samples using high spatial resolution ToF-SIMS analysis: (1) species relating to the preparation and photo-induced oxidation of CdS yellow pigments (2) varying amounts of long-chain fatty acids present in both the paint and primary ground layer and (3) specific amino acid fragments, possibly relating to the painting's complex restoration history. ToF-SIMS's ability to discern both organic and inorganic species via cross-sectional imaging was used to compare samples collected from Le Bonheur de vivre to artificially aged reference paints in an effort to gather mechanistic information relating to alteration processes that have been previously explored using μXANES, SR-μXRF, SEM-EDX, and SR-FTIR. The relatively high sensitivity offered by ToF-SIMS imaging coupled to the high spatial resolution allowed for the positive identification of degradation products (such as cadmium oxalate) in specific paint regions that have before been unobserved. The imaging of organic materials has provided an insight into the extent of destruction of the original binding medium, as well as

  10. ToF-SIMS imaging of molecular-level alteration mechanisms in Le Bonheur de vivre by Henri Matisse

    International Nuclear Information System (INIS)

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has recently been shown to be a valuable tool for cultural heritage studies, especially when used in conjunction with established analytical techniques in the field. The ability of ToF-SIMS to simultaneously image inorganic and organic species within a paint cross section at micrometer-level spatial resolution makes it a uniquely qualified analytical technique to aid in further understanding the processes of pigment and binder alteration, as well as pigment-binder interactions. In this study, ToF-SIMS was used to detect and image both molecular and elemental species related to CdS pigment and binding medium alteration on the painting Le Bonheur de vivre (1905-1906, The Barnes Foundation) by Henri Matisse. Three categories of inorganic and organic components were found throughout Le Bonheur de vivre and co-localized in cross-sectional samples using high spatial resolution ToF-SIMS analysis: (1) species relating to the preparation and photo-induced oxidation of CdS yellow pigments (2) varying amounts of long-chain fatty acids present in both the paint and primary ground layer and (3) specific amino acid fragments, possibly relating to the painting's complex restoration history. ToF-SIMS's ability to discern both organic and inorganic species via cross-sectional imaging was used to compare samples collected from Le Bonheur de vivre to artificially aged reference paints in an effort to gather mechanistic information relating to alteration processes that have been previously explored using μXANES, SR-μXRF, SEM-EDX, and SR-FTIR. The relatively high sensitivity offered by ToF-SIMS imaging coupled to the high spatial resolution allowed for the positive identification of degradation products (such as cadmium oxalate) in specific paint regions that have before been unobserved. The imaging of organic materials has provided an insight into the extent of destruction of the original binding medium, as well as

  11. Brief anesthesia by isoflurane alters plasma corticosterone levels distinctly in male and female rats: Implications for tissue collection methods.

    Science.gov (United States)

    Bekhbat, Mandakh; Merrill, Liana; Kelly, Sean D; Lee, Vanessa K; Neigh, Gretchen N

    2016-05-15

    Euthanasia by anesthetic agents is commonly performed prior to tissue collection in order to minimize pain and distress to the animal. However, depending on their mechanism of action as well as administration regimen, different methods of anesthesia may trigger an acute stress response through engaging the hypothalamic-pituitary-adrenal (HPA) axis, which can impact numerous other physiological processes that the researcher may wish to examine as endpoints. We investigated the effects of the commonly used anesthetic agent isoflurane on two different endpoints related to the stress response: plasma corticosterone levels and gene expression of the glucocorticoid receptor (GR) as well as several of its regulators including FK506-binding protein 51 (Fkbp5) in the hippocampus of male and female rats. Our results indicate that brief exposure to anesthesia by isoflurane prior to decapitation can alter plasma corticosterone levels differentially in male and female rats within minutes without impacting gene expression in the hippocampus. We conclude that collection methods can influence stress-related physiological endpoints in female rats and the potential influence of even brief anesthesia as well as sex differences in response to anesthesia should be evaluated during the experimental design process and data interpretation. This finding is particularly important in light of new NIH standards regarding sex and reproducibility, and care should be taken to be certain that sex differences in endpoints of interest are not an artifact of sex differences in response to collection paradigms. PMID:26946276

  12. Projected near-future CO2 levels increase activity and alter defensive behaviours in the tropical squid Idiosepius pygmaeus

    Directory of Open Access Journals (Sweden)

    Blake L. Spady

    2014-10-01

    Full Text Available Carbon dioxide (CO2 levels projected to occur in the oceans by the end of this century cause a range of behavioural effects in fish, but whether other highly active marine organisms, such as cephalopods, are similarly affected is unknown. We tested the effects of projected future CO2 levels (626 and 956 µatm on the behaviour of male two-toned pygmy squid, Idiosepius pygmaeus. Exposure to elevated CO2 increased the number of active individuals by 19–25% and increased movement (number of line-crosses by nearly 3 times compared to squid at present-day CO2. Squid vigilance and defensive behaviours were also altered by elevated CO2 with >80% of individuals choosing jet escape responses over defensive arm postures in response to a visual startle stimulus, compared with 50% choosing jet escape responses at control CO2. In addition, more escape responses were chosen over threat behaviours in body pattern displays at elevated CO2 and individuals were more than twice as likely to use ink as a defence strategy at 956 µatm CO2, compared with controls. Increased activity could lead to adverse effects on energy budgets as well as increasing visibility to predators. A tendency to respond to a stimulus with escape behaviours could increase survival, but may also be energetically costly and could potentially lead to more chases by predators compared with individuals that use defensive postures. These results demonstrate that projected future ocean acidification affects the behaviours of a tropical squid species.

  13. Projected near-future CO2 levels increase activity and alter defensive behaviours in the tropical squid Idiosepius pygmaeus.

    Science.gov (United States)

    Spady, Blake L; Watson, Sue-Ann; Chase, Tory J; Munday, Philip L

    2014-01-01

    Carbon dioxide (CO2) levels projected to occur in the oceans by the end of this century cause a range of behavioural effects in fish, but whether other highly active marine organisms, such as cephalopods, are similarly affected is unknown. We tested the effects of projected future CO2 levels (626 and 956 µatm) on the behaviour of male two-toned pygmy squid, Idiosepius pygmaeus. Exposure to elevated CO2 increased the number of active individuals by 19-25% and increased movement (number of line-crosses) by nearly 3 times compared to squid at present-day CO2. Squid vigilance and defensive behaviours were also altered by elevated CO2 with >80% of individuals choosing jet escape responses over defensive arm postures in response to a visual startle stimulus, compared with 50% choosing jet escape responses at control CO2. In addition, more escape responses were chosen over threat behaviours in body pattern displays at elevated CO2 and individuals were more than twice as likely to use ink as a defence strategy at 956 µatm CO2, compared with controls. Increased activity could lead to adverse effects on energy budgets as well as increasing visibility to predators. A tendency to respond to a stimulus with escape behaviours could increase survival, but may also be energetically costly and could potentially lead to more chases by predators compared with individuals that use defensive postures. These results demonstrate that projected future ocean acidification affects the behaviours of a tropical squid species. PMID:25326517

  14. Changes in Dietary Fat Content Rapidly Alters the Mouse Plasma Coagulation Profile without Affecting Relative Transcript Levels of Coagulation Factors

    Science.gov (United States)

    van Diepen, Janna A.; Verhoef, Daniël; Voshol, Peter J.; Reitsma, Pieter H.; van Vlijmen, Bart J. M.

    2015-01-01

    Background Obesity is associated with a hypercoagulable state and increased risk for thrombotic cardiovascular events. Objective Establish the onset and reversibility of the hypercoagulable state during the development and regression of nutritionally-induced obesity in mice, and its relation to transcriptional changes and clearance rates of coagulation factors as well as its relation to changes in metabolic and inflammatory parameters. Methods Male C57BL/6J mice were fed a low fat (10% kcal as fat; LFD) or high fat diet (45% kcal as fat; HFD) for 2, 4, 8 or 16 weeks. To study the effects of weight loss, mice were fed the HFD for 16 weeks and switched to the LFD for 1, 2 or 4 weeks. For each time point analyses of plasma and hepatic mRNA levels of coagulation factors were performed after overnight fasting, as well as measurements of circulating metabolic and inflammatory parameters. Furthermore, in vivo clearance rates of human factor (F) VII, FVIII and FIX proteins were determined after 2 weeks of HFD-feeding. Results HFD feeding gradually increased the body and liver weight, which was accompanied by a significant increase in plasma glucose levels from 8 weeks onwards, while insulin levels were affected after 16 weeks. Besides a transient rise in cytokine levels at 2 weeks after starting the HFD, no significant effect on inflammation markers was present. Increased plasma levels of fibrinogen, FII, FVII, FVIII, FIX, FXI and FXII were observed in mice on a HFD for 2 weeks, which in general persisted throughout the 16 weeks of HFD-feeding. Interestingly, with the exception of FXI the effects on plasma coagulation levels were not paralleled by changes in relative transcript levels in the liver, nor by decreased clearance rates. Switching from HFD to LFD reversed the HFD-induced procoagulant shift in plasma, again not coinciding with transcriptional modulation. Conclusions Changes in dietary fat content rapidly alter the mouse plasma coagulation profile, thereby

  15. Meta-diamide insecticides acting on distinct sites of RDL GABA receptor from those for conventional noncompetitive antagonists.

    Science.gov (United States)

    Nakao, Toshifumi; Banba, Shinich; Nomura, Michikazu; Hirase, Kangetsu

    2013-04-01

    The RDL GABA receptor is an attractive target of insecticides. Here we demonstrate that meta-diamides [3-benzamido-N-(4-(perfluoropropan-2-yl)phenyl)benzamides] are a distinct class of RDL GABA receptor antagonists showing high insecticidal activity against Spodoptera litura. We also suggest that the mode of action of the meta-diamides is distinct from that of conventional noncompetitive antagonists (NCAs), such as fipronil, picrotoxin, lindane, dieldrin, and α-endosulfan. Using a membrane potential assay, we examined the effects of the meta-diamide 3-benzamido-N-(2-bromo-4-(perfluoropropan-2-yl)-6-(trifluoromethyl)phenyl)-2-fluorobenzamide (meta-diamide 7) and NCAs on mutant Drosophila RDL GABA receptors expressed in Drosophila Mel-2 cells. NCAs had little or no inhibitory activity against at least one of the three mutant receptors (A2'S, A2'G, and A2'N), which were reported to confer resistance to NCAs. In contrast, meta-diamide 7 inhibited all three A2' mutant receptors, at levels comparable to its activity with the wild-type receptor. Furthermore, the A2'S·T6'V mutation almost abolished the inhibitory effects of all NCAs. However, meta-diamide 7 inhibited the A2'S・T6'S mutant receptor at the same level as its activity with the wild-type receptor. In contrast, a G336M mutation in the third transmembrane domain of the RDL GABA receptor abolished the inhibitory activities of meta-diamide 7, although the G336M mutation had little effect on the inhibitory activities of conventional NCAs. Molecular modeling studies also suggested that the binding site of meta-diamides was different from those of NCAs. Meta-diamide insecticides are expected to be prominent insecticides effective against A2' mutant RDL GABA receptors with a different mode of action. PMID:23416568

  16. Actions of insecticides on the insect GABA receptor complex

    International Nuclear Information System (INIS)

    The actions of insecticides on the insect gamma-aminobutyric acid (GABA) receptor were investigated using [35S]t-butylbicyclophosphorothionate [( 35S]TBPS) binding and voltage-clamp techniques. Specific binding of [35S]TBPS to a membrane homogenate derived from the brain of Locusta migratoria locusts is characterised by a Kd value of 79.3 ± 2.9 nM and a Bmax value of 1770 ± 40 fmol/mg protein. [35S]TBPS binding is inhibited by mM concentrations of barbiturates and benzodiazepines. In contrast dieldrin, ivermectin, lindane, picrotoxin and TBPS are inhibitors of [35S]TBPS binding at the nanomolar range. Bicuculline, baclofen and pyrethroid insecticides have no effect on [35S]TBPS binding. These results are similar to those obtained in electrophysiological studies of the current elicited by GABA in both Locusta and Periplaneta americana central neurones. Noise analysis of the effects of lindane, TBPS, dieldrin and picrotoxin on the cockroach GABA responses reveals that these compounds decrease the variance of the GABA-induced current but have no effect on its mean open time. All these compounds, with the exception of dieldrin, significantly decrease the conductance of GABA-evoked single current

  17. Actions of insecticides on the insect GABA receptor complex

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, I.; Hawkins, C.A.; Taylor, A.M.; Beadle, D.J. (School of Biological and Molecular Sciences, Oxford Polytechnic, Headington, Oxford (England))

    1991-01-01

    The actions of insecticides on the insect gamma-aminobutyric acid (GABA) receptor were investigated using (35S)t-butylbicyclophosphorothionate (( 35S)TBPS) binding and voltage-clamp techniques. Specific binding of (35S)TBPS to a membrane homogenate derived from the brain of Locusta migratoria locusts is characterised by a Kd value of 79.3 {plus minus} 2.9 nM and a Bmax value of 1770 {plus minus} 40 fmol/mg protein. (35S)TBPS binding is inhibited by mM concentrations of barbiturates and benzodiazepines. In contrast dieldrin, ivermectin, lindane, picrotoxin and TBPS are inhibitors of (35S)TBPS binding at the nanomolar range. Bicuculline, baclofen and pyrethroid insecticides have no effect on (35S)TBPS binding. These results are similar to those obtained in electrophysiological studies of the current elicited by GABA in both Locusta and Periplaneta americana central neurones. Noise analysis of the effects of lindane, TBPS, dieldrin and picrotoxin on the cockroach GABA responses reveals that these compounds decrease the variance of the GABA-induced current but have no effect on its mean open time. All these compounds, with the exception of dieldrin, significantly decrease the conductance of GABA-evoked single current.

  18. Neurochemical correlates of. gamma. -aminobutyrate (GABA) inhibition in cat visual cortex

    Energy Technology Data Exchange (ETDEWEB)

    Balcar, V.J.; Dreher, B. (Univ. of Sydney (Australia))

    1990-01-01

    High affinity binding of ({sup 3}H){gamma}-aminobutyric acid (GABA) to neuronal membranes from different parts of cat visual cortex was tested for sensitivity to GABA{sub A} agonists isoguvacine and THIP, GABA{sub A} antagonist SR95531 and GABA{sub B} agonist baclofen. Some of the GABA{sub A}-binding sites were found to have a very low affinity for THIP, suggesting the presence and, possibly, uneven distribution of non-synaptic GABA{sub A} receptors in cat visual cortex. There were no differences in K{sub m} and V{sub max} values of high affinity uptake of GABA and in the potency of K{sup +}-stimulated release of GABA, between primary and association cortices. Consequently, the present results indicate that despite the anatomical and physiological differences between the primary and association feline visual cortices the neurochemical characteristics of GABAergic inhibition are very similar in the two regions.

  19. Paradoxical widespread c-Fos expression induced by a GABA agonist in the forebrain of transgenic mice with ectopic expression of the GABA(A) α6 subunit.

    Science.gov (United States)

    Hellsten, K S; Linden, A-M; Korpi, E R

    2015-05-01

    A GABA-site agonist gaboxadol (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol) at 3 mg/kg induces strong anxiolytic response in a transgenic Thy1α6 mouse line ectopically expressing the GABA(A) receptor α6 subunit gene under the Thy-1.2 promoter. Now, we compared brain activation patterns between Thy1α6 and wild-type mice to identify brain structures potentially mediating this anxiolytic response. Acutely efficient anxiolytics such as benzodiazepines typically depress most brain regions while activating specifically neurons within the central extended amygdala. Gaboxadol treatment (3 mg/kg, i.p., 2 h) induced a significant increase in c-Fos expression selectively in many Thy1α6 brain regions including the limbic cortex, anterior olfactory nucleus, septal area and central and basolateral nuclei of amygdala. It failed to activate the lateral part of mediodorsal thalamic nucleus (MDL) in the Thy1α6 mice that was activated in the wild-type mice. Detailed mapping of the α6 subunit mRNA by in situ hybridization revealed expression in the middle layers of the isocortex, olfactory areas, hippocampal formation and basolateral nucleus of amygdala (BLA) in the Thy1α6 forebrain. The ligand autoradiographies (t-butylbicyclophosphoro[(35)S]thionate ([(35)S]TBPS) and [(3)H]Ro 15-4513) revealed high levels of pharmacologically active extrasynaptic α6β and α6βγ2 GABA(A) receptors in these same areas. However, c-Fos induction by gaboxadol treatment in Thy1α6 brain was not restricted to areas highly expressing the α6-containing GABA(A) receptors suggesting that indirect pathways lead to the paradoxically widespread activation. Interestingly, the activation pattern by gaboxadol at the dose that is anxiolytic in Thy1α6 mice resembled closely that observed after various fear- and stress-provoking challenges. However, our results are consistent with a recent observation that optogenetic activation of specific neuronal pathways in the extended amygdala mediates anxiolytic

  20. Refuting the challenges of the developmental shift of polarity of GABA actions: GABA more exciting than ever!

    Directory of Open Access Journals (Sweden)

    Melanie A Woodin

    2012-08-01

    Full Text Available Abstract During brain development, there is a progressive reduction of intracellular chloride associated with a shift in GABA polarity: GABA depolarizes and occasionally excites immature neurons, subsequently hyperpolarizing them at later stages of development. This sequence, which has been observed in a wide range of animal species, brain structures and preparations, is thought to play an important role in activity-dependent formation and modulation of functional circuits. This sequence has also been considerably reinforced recently with new data pointing to an evolutionary preserved rule. In a recent ‘Hypothesis and Theory Article’, the excitatory action of GABA in early brain development is suggested to be “an experimental artefact” (Bregestovski and Bernard, 2012. The authors suggest that the excitatory action of GABA is due to an inadequate/insufficient energy supply in glucose-perfused slices and/or to the damage produced by the slicing procedure. However, these observations have been repeatedly contradicted by many groups and are inconsistent with a large body of evidence including the fact that the developmental shift is neither restricted to slices nor to rodents. We summarize the overwhelming evidence in support of both excitatory GABA during development, and the implications this has in developmental neurobiology.

  1. GABA-B receptor activation and conflict behavior

    Energy Technology Data Exchange (ETDEWEB)

    Ketelaars, C.E.J.; Bollen, E.L.; Rigter, H.; Bruinvels, J.

    1988-01-01

    Baclofen and oxazepam enhance extinction of conflict behavior in the Geller-Seifter test while baclofen and diazepam release punished behavior in Vogel's conflict test. In order to investigate the possibility that the effect of the selective GABA-B receptor agonist baclofen is mediated indirectly via the GABA-A/benzodiazepine receptor complex, the effect of pretreatment of rats with baclofen on (/sup 3/H)-diazepam binding to washed and unwashed cortical and cerebellar membranes of rats has been studied. Baclofen pretreatment increase Bmax in washed cerebellar membranes when bicuculline was present in the incubation mixture. No effect was seen in cortical membranes. The present results render it unlikely that the effect of baclofen on extinction of conflict behavior and punished drinking is mediated via the GABA-A/benzodiazepine receptor complex. 50 references, 1 figure, 4 tables.

  2. GABA-B receptor activation and conflict behavior

    International Nuclear Information System (INIS)

    Baclofen and oxazepam enhance extinction of conflict behavior in the Geller-Seifter test while baclofen and diazepam release punished behavior in Vogel's conflict test. In order to investigate the possibility that the effect of the selective GABA-B receptor agonist baclofen is mediated indirectly via the GABA-A/benzodiazepine receptor complex, the effect of pretreatment of rats with baclofen on [3H]-diazepam binding to washed and unwashed cortical and cerebellar membranes of rats has been studied. Baclofen pretreatment increase Bmax in washed cerebellar membranes when bicuculline was present in the incubation mixture. No effect was seen in cortical membranes. The present results render it unlikely that the effect of baclofen on extinction of conflict behavior and punished drinking is mediated via the GABA-A/benzodiazepine receptor complex. 50 references, 1 figure, 4 tables

  3. Drosophila neuroligin 4 regulates sleep through modulating GABA transmission.

    Science.gov (United States)

    Li, Yi; Zhou, Zikai; Zhang, Xinwang; Tong, Huawei; Li, Peipei; Zhang, Zi Chao; Jia, Zhengping; Xie, Wei; Han, Junhai

    2013-09-25

    Sleep is an essential and evolutionarily conserved behavior that is closely related to synaptic function. However, whether neuroligins (Nlgs), which are cell adhesion molecules involved in synapse formation and synaptic transmission, are involved in sleep is not clear. Here, we show that Drosophila Nlg4 (DNlg4) is highly expressed in large ventral lateral clock neurons (l-LNvs) and that l-LNv-derived DNlg4 is essential for sleep regulation. GABA transmission is impaired in mutant l-LNv, and sleep defects in dnlg4 mutant flies can be rescued by genetic manipulation of GABA transmission. Furthermore, dnlg4 mutant flies exhibit a severe reduction in GABAA receptor RDL clustering, and DNlg4 associates with RDLs in vivo. These results demonstrate that DNlg4 regulates sleep through modulating GABA transmission in l-LNvs, which provides the first known link between a synaptic adhesion molecule and sleep in Drosophila. PMID:24068821

  4. Rapid regulation of tonic GABA currents in cultured rat hippocampal neurons

    OpenAIRE

    Ransom, Christopher B.; Tao, Wucheng; Wu, Yuanming; Spain, William J; Richerson, George B.

    2012-01-01

    Subacute and chronic changes in tonic GABAergic inhibition occur in human and experimental epilepsy. Less is known about how tonic inhibition is modulated over shorter time frames (seconds). We measured endogenous tonic GABA currents from cultured rat hippocampal neurons to evaluate how they are affected by 1) transient increases in extracellular GABA concentration ([GABA]), 2) transient postsynaptic depolarization, and 3) depolarization of presynaptic cells. Transient increases in [GABA] (1 ...

  5. Photorelease of GABA with Visible Light Using an Inorganic Caging Group

    OpenAIRE

    Rial Verde, Emiliano M.; Zayat, Leonardo; Etchenique, Roberto; Yuste, Rafael

    2008-01-01

    We describe the selective photorelease of γ-amino butyric acid (GABA) with a novel caged-GABA compound that uses a ruthenium complex as photosensor. This compound (“RuBi-GABA”) can be excited with visible wavelengths, providing greater tissue penetration, less photo-toxicity, and faster photorelease kinetics than currently used UV light-sensitive caged compounds. Using pyramidal neurons from neocortical brain slices, we show that RuBi-GABA uncaging induces GABA-A receptor-mediated responses, ...

  6. Pentameric ligand-gated ion channel ELIC is activated by GABA and modulated by benzodiazepines

    OpenAIRE

    Spurny, R.; Ramerstorfer, J.; Price, K; Brams, M.; M. Ernst; Nury, H.; Verheij, M.; Legrand, P.; Bertrand, D.; Bertrand, S.; Dougherty, D A; de Esch, I. J. P.; Corringer, P.-J.; Sieghart, W.; Lummis, S. C. R.

    2012-01-01

    GABA_A receptors are pentameric ligand-gated ion channels involved in fast inhibitory neurotransmission and are allosterically modulated by the anxiolytic, anticonvulsant, and sedative-hypnotic benzodiazepines. Here we show that the prokaryotic homolog ELIC also is activated by GABA and is modulated by benzodiazepines with effects comparable to those at GABA_A receptors. Crystal structures reveal important features of GABA recognition and indicate that benzodiazepines, depending on their conc...

  7. Effect of GABA, a Bacterial Metabolite, on Pseudomonas fluorescens Surface Properties and Cytotoxicity

    OpenAIRE

    Feuilloley, Marc G. J.; Nicole Orange; Laure Taupin; Sylvie Chevalier; Cécile Duclairoir-Poc; Lily Mijouin; Mélanie Hillion; Annelise Chapalain; Audrey Dagorn

    2013-01-01

    Different bacterial species and, particularly Pseudomonas fluorescens, can produce gamma-aminobutyric acid (GABA) and express GABA-binding proteins. In this study, we investigated the effect of GABA on the virulence and biofilm formation activity of different strains of P. fluorescens. Exposure of a psychotropic strain of P. fluorescens (MF37) to GABA (10−5 M) increased its necrotic-like activity on eukaryotic (glial) cells, but reduced its apoptotic effect. Conversely, muscimol and bicuculli...

  8. Celsr3 is required for normal development of GABA circuits in the inner retina.

    Directory of Open Access Journals (Sweden)

    Alaron Lewis

    2011-08-01

    Full Text Available The identity of the specific molecules required for the process of retinal circuitry formation is largely unknown. Here we report a newly identified zebrafish mutant in which the absence of the atypical cadherin, Celsr3, leads to a specific defect in the development of GABAergic signaling in the inner retina. This mutant lacks an optokinetic response (OKR, the ability to visually track rotating illuminated stripes, and develops a super-normal b-wave in the electroretinogram (ERG. We find that celsr3 mRNA is abundant in the amacrine and ganglion cells of the retina, however its loss does not affect synaptic lamination within the inner plexiform layer (IPL or amacrine cell number. We localize the ERG defect pharmacologically to a late-stage disruption in GABAergic modulation of ON-bipolar cell pathway and find that the DNQX-sensitive fast b1 component of the ERG is specifically affected in this mutant. Consistently, we find an increase in GABA receptors on mutant ON-bipolar terminals, providing a direct link between the observed physiological changes and alterations in GABA signaling components. Finally, using blastula transplantation, we show that the lack of an OKR is due, at least partially, to Celsr3-mediated defects within the brain. These findings support the previously postulated inner retina origin for the b1 component and reveal a new role for Celsr3 in the normal development of ON visual pathway circuitry in the inner retina.

  9. Role of GABA-active neurosteroids in the efficacy of metyrapone against cocaine addiction.

    Science.gov (United States)

    Schmoutz, Christopher D; Guerin, Glenn F; Goeders, Nicholas E

    2014-09-01

    Previous research has demonstrated a complicated role for stress and HPA axis activation in potentiating various cocaine-related behaviors in preclinical models of drug dependence. However, the investigation of several antiglucocorticoid therapies has yielded equivocal results in reducing cocaine-related behaviors, possibly because of varying mechanisms of actions. Specifically, research suggests that metyrapone (a corticosterone synthesis inhibitor) may reduce cocaine self-administration in rats via a nongenomic, extra-adrenal mechanism without altering plasma corticosterone. In the current experiments, male rats were trained to self-administer cocaine infusions and food pellets in a multiple, alternating schedule of reinforcement. Metyrapone pretreatment dose-dependently decreased cocaine self-administration as demonstrated previously. Pharmacological inhibition of neurosteroid production by finasteride had significant effects on cocaine self-administration, regardless of metyrapone pretreatment. However, metyrapone's effects on cocaine self-administration were significantly attenuated with bicuculline pretreatment, suggesting a role for GABA-active neurosteroids in cocaine-reinforced behaviors. In vitro binding data also confirmed that metyrapone does not selectively bind to GABA-related proteins. The results of these experiments support the hypothesis that metyrapone may increase neurosteroidogenesis to produce effects on cocaine-related behaviors. PMID:24959859

  10. Omega-3 Fatty Acid Enriched Chevon (Goat Meat Lowers Plasma Cholesterol Levels and Alters Gene Expressions in Rats

    Directory of Open Access Journals (Sweden)

    Mahdi Ebrahimi

    2014-01-01

    Full Text Available In this study, control chevon (goat meat and omega-3 fatty acid enriched chevon were obtained from goats fed a 50% oil palm frond diet and commercial goat concentrate for 100 days, respectively. Goats fed the 50% oil palm frond diet contained high amounts of α-linolenic acid (ALA in their meat compared to goats fed the control diet. The chevon was then used to prepare two types of pellets (control or enriched chevon that were then fed to twenty-male-four-month-old Sprague-Dawley rats (n=10 in each group for 12 weeks to evaluate their effects on plasma cholesterol levels, tissue fatty acids, and gene expression. There was a significant increase in ALA and docosahexaenoic acid (DHA in the muscle tissues and liver of the rats fed the enriched chevon compared with the control group. Plasma cholesterol also decreased (P<0.05 in rats fed the enriched chevon compared to the control group. The rat pellets containing enriched chevon significantly upregulated the key transcription factor PPAR-γ and downregulated SREBP-1c expression relative to the control group. The results showed that the omega-3 fatty acid enriched chevon increased the omega-3 fatty acids in the rat tissues and altered PPAR-γ and SREBP-1c genes expression.

  11. Potentiating action of propofol at GABAA receptors of retinal bipolar cells

    DEFF Research Database (Denmark)

    Yue, Lan; Xie, An; Bruzik, Karol S;

    2011-01-01

    specific retinal neurons. The authors investigated the action of propofol on GABA-elicited membrane current responses of retinal bipolar cells, which have both GABA(A) and GABA(C) receptors. Methods. Single, enzymatically dissociated bipolar cells obtained from rat retina were treated with propofol...

  12. Selective mGAT2 (BGT-1) GABA Uptake Inhibitor

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Jørgensen, Lars; Madsen, Karsten Kirkegaard;

    2013-01-01

    β-Amino acids sharing a lipophilic diaromatic side chain were synthesized and characterized pharmacologically on mouse GABA transporter subtypes mGAT1−4. The parent amino acids were also characterized. Compounds 13a, 13b, and 17b displayed more than 6-fold selectivity for mGAT2 over mGAT1. Compound...... 17b displayed anticonvulsive properties inferring a role of mGAT2 in epileptic disorders. These results provide new neuropharmacological tools and a strategy for designing subtype selective GABA transport inhibitors....

  13. Disminución del número de neuronas que expresan GABA en la corteza cerebral de ratones infectados con rabia Decreased number neurons expressing GABA in the cerebral cortex of rabies-infected mice

    Directory of Open Access Journals (Sweden)

    Orlando Torres-Fernández

    2007-12-01

    Full Text Available

    Introducción. Algunos signos clínicos de la rabia y estudios experimentales previos sugieren que esta infección viral podría afectar al sistema GABAérgico.
    Objetivo. Evaluar el efecto de la infección con el virus de la rabia sobre la expresión de GABA en neuronas de la corteza cerebral de ratón.
    Materiales y métodos. Se inocularon ratones adultos con virus CVS de la rabia por vía intramuscular. Los animales se sacrificaron en la etapa terminal de la enfermedad y se fijaron por perfusión con paraformaldehído al 4% y glutaraldehído al 1%. Se procesaron cortes coronales de cerebro obtenidos en un Vibratome®, mediante inmunohistoquímica para identificar neuronas GABAérgicas en la corteza cerebral. Se realizaron conteos y análisis cuantitativo de las neuronas positivas para GABA en muestras de ratones normales e infectados.
    Resultados. En los animales infectados con rabia no se alteró el patrón de distribución de las neuronas GABAérgicas corticales pero su número disminuyó significativamente. El promedio de células positivas para GABA en 1 mm2 de corteza fue de 293±32 en los controles y de 209±13 en los infectados. Por otra parte, el valor promedio del área de los perfiles neuronales positivos para GABA aumentó significativamente de 104±8 μm2 en los controles a 122±10 μm2 en las muestras infectadas, debido a que la pérdida de células positivas para GABA fue más evidente en las neuronas de menor tamaño. No obstante, el rango de tamaños de las células inmunopositivas para GABA fue similar en muestras de animales normales e infectados.
    Conclusiones. Este trabajo aporta nueva evidencia en favor de la hipótesis que propone la participación del GABA en la fisiopatología de la rabia.

    Introduction. GABAergic neurons synthesize and release gamma-aminobutyric acid, the predominant inhibitory neurotransmitter in the brain. Certain clinical signs of rabies and previous experimental studies

  14. Low nanomolar GABA effects at extrasynaptic a4ß1/ß3delta GABAA receptor subtypes indicate a different binding mode for GABA at these receptors

    DEFF Research Database (Denmark)

    Karim, Nasiara; Wellendorph, Petrine; Absalom, Nathan;

    2012-01-01

    Ionotropic GABA(A) receptors are a highly heterogenous population of receptors assembled from a combination of multiple subunits. The aims of this study were to characterize the potency of GABA at human recombinant d-containing extrasynaptic GABA(A) receptors expressed in Xenopus oocytes using the...... two-electrode voltage clamp technique, and to investigate, using site-directed mutagenesis, the molecular determinants for GABA potency at a4ß3d GABA(A) receptors. a4/d-Containing GABA(A) receptors displayed high sensitivity to GABA, with mid-nanomolar concentrations activating a4ß1d (EC(50)=24nM) and...... a4ß3d (EC(50)=12nM) receptors. In the majority of oocytes expressing a4ß3d subtypes, GABA produced a biphasic concentration-response curve, and activated the receptor with low and high concentrations (EC(50)(1)=16nM; EC(50)(2)=1.2µM). At a4ß2d, GABA had low micromolar activity (EC(50)=1µM). An...

  15. Change in Auxin and Cytokinin Levels Coincides with Altered Expression of Branching Genes during Axillary Bud Outgrowth in Chrysanthemum.

    Science.gov (United States)

    Dierck, Robrecht; De Keyser, Ellen; De Riek, Jan; Dhooghe, Emmy; Van Huylenbroeck, Johan; Prinsen, Els; Van Der Straeten, Dominique

    2016-01-01

    In the production and breeding of Chrysanthemum sp., shoot branching is an important quality aspect as the outgrowth of axillary buds determines the final plant shape. Bud outgrowth is mainly controlled by apical dominance and the crosstalk between the plant hormones auxin, cytokinin and strigolactone. In this work the hormonal and genetic regulation of axillary bud outgrowth was studied in two differently branching cut flower Chrysanthemum morifolium (Ramat) genotypes. C17 is a split-type which forms an inflorescence meristem after a certain vegetative period, while C18 remains vegetative under long day conditions. Plant growth of both genotypes was monitored during 5 subsequent weeks starting one week before flower initiation occurred in C17. Axillary bud outgrowth was measured weekly and samples of shoot apex, stem and axillary buds were taken during the first two weeks. We combined auxin and cytokinin measurements by UPLC-MS/MS with RT-qPCR expression analysis of genes involved in shoot branching regulation pathways in chrysanthemum. These included bud development genes (CmBRC1, CmDRM1, CmSTM, CmLsL), auxin pathway genes (CmPIN1, CmTIR3, CmTIR1, CmAXR1, CmAXR6, CmAXR2, CmIAA16, CmIAA12), cytokinin pathway genes (CmIPT3, CmHK3, CmRR1) and strigolactone genes (CmMAX1 and CmMAX2). Genotype C17 showed a release from apical dominance after floral transition coinciding with decreased auxin and increased cytokinin levels in the subapical axillary buds. As opposed to C17, C18 maintained strong apical dominance with vegetative growth throughout the experiment. Here high auxin levels and decreasing cytokinin levels in axillary buds and stem were measured. A differential expression of several branching genes accompanied the different hormonal change and bud outgrowth in C17 and C18. This was clear for the strigolactone biosynthesis gene CmMAX1, the transcription factor CmBRC1 and the dormancy associated gene CmDRM1, that all showed a decreased expression in C17 at floral

  16. The betaine/GABA transporter and betaine: roles in brain, kidney and liver

    Directory of Open Access Journals (Sweden)

    Stephen A Kempson

    2014-04-01

    Full Text Available The physiological roles of the betaine/GABA transporter (BGT1; slc6a12 are still being debated. BGT1 is a member of the solute carrier family 6 (the neurotransmitter, sodium symporter transporter family and mediates cellular uptake of betaine and GABA in a sodium- and chloride- dependent process. Most of the studies of BGT1 concern its function and regulation in the kidney medulla where its role is best understood. The conditions here are hostile due to hyperosmolarity and significant concentrations of NH4Cl and urea. To withstand the hyperosmolarity, cells trigger osmotic adaptation, involving concentration of a transcriptional factor TonEBP/NFAT5 in the nucleus, and accumulate betaine and other osmolytes. Data from renal cells in culture, primarily MDCK, revealed that transcriptional regulation of BGT1 by TonEBP/NFAT5 is relatively slow. To allow more acute control of the abundance of BGT1 protein in the plasma membrane, there is also post-translation regulation of BGT1 protein trafficking which is dependent on intracellular calcium and ATP. Further, betaine may be important in liver metabolism as a methyl donor. In fact, in the mouse the liver is the organ with the highest content of BGT1. Hepatocytes express high levels of both BGT1 and the only enzyme that can metabolize betaine, namely betaine:homocysteine –S-methyltransferase (BHMT1. The BHMT1 enzyme removes a methyl group from betaine and transfers it to homocysteine, a potential risk factor for cardiovascular disease. Finally, BGT1 has been proposed to play a role in controlling brain excitability and thereby represents a target for anticonvulsive drug development. The latter hypothesis is controversial due to very low expression levels of BGT1 relative to other GABA transporters in brain, and also the primary location of BGT1 at the surface of the brain in the leptomeninges. These issues are discussed in detail.

  17. Rats selectively bred for low levels of 50 kHz ultrasonic vocalizations exhibit alterations in early social motivation.

    Science.gov (United States)

    Harmon, K M; Cromwell, H C; Burgdorf, J; Moskal, J R; Brudzynski, S M; Kroes, R A; Panksepp, J

    2008-05-01

    In rats, the rates of 50 kHz ultrasonic vocalizations (USVs) can be used as a selective breeding phenotype and variations in this phenotype can be an indicator of affective states. The 50 kHz USV is elicited by rewarding stimuli (e.g., food, sexual behavior) and therefore can express a positive affective state. Conversely, the 22 kHz USV is elicited by aversive stimuli (e.g., presence of a predator, social defeat) indicating a negative affective state. In the present study, we tested the effect of selectively breeding for 50 kHz USVs on a variety of maternal social/emotional behaviors in young rat pups (PND 10-12). These measures consisted of an assessment of isolation calls and conditioned odor preference paradigm. Results indicate that animals selected for low levels of 50 kHz USVs show the greatest alterations in social behaviors compared to the control animals. The low line animals had an increase in isolation calls tested during place preference conditioning and a decrease in 50 kHz ultrasonic calls in all conditions. These same low line animals failed to show a typical preference for a maternally-associated odor during the place preference test. The different social behaviors of the high line animals did not consistently vary from those of the control group. These results have important implications for the study of genetic and epigenetic mechanisms underlying emotional states, and possibly contribute to the research underlying the emotional changes in developmental disorders such as autistic spectrum disorder by providing a novel animal model that displays communication deficits that are interdependent with significant social behavioral impairments. PMID:18393285

  18. Synthesis and Evaluation of Novel Aromatic Substrates and Competitive Inhibitors of GABA Aminotransferase

    OpenAIRE

    Clift, Michael D.; Silverman, Richard B.

    2007-01-01

    The design, synthesis, and evaluation of novel γ-aminobutyric acid aminotransferase (GABA-AT) inhibitors and inactivators can lead to the discovery of new GABA-related therapeutics. To this end, a series of aromatic amino acid compounds was synthesized to aid in the design of new inhibitors and inactivators of GABA-AT. All compounds were tested as competitive inhibitors of GABA-AT. The amino acids with benzylic amines were also tested as substrates for GABA-AT. It was found that these compoun...

  19. Action of tremorgenic mycotoxins on GABA/sub A/ receptor

    International Nuclear Information System (INIS)

    The effects of four tremorgenic and one nontremorgenic mycotoxins were studied on γ-aminobutyric acid (GABA/sub A/) receptor binding and function in rat brain and on binding of a voltage-operated Cl- channel in Torpedo electric organ. None of the mycotoxins had significant effect on [3H]muscimol or [3H]flunitrazepam binding to the GAMA/sup A/ receptor. However, only the four tremorgenic mycotoxins inhibited GABA-induced 36Cl- influx and [35S]t-butylbicyclophosphorothionate ([35S]TBPS) binding in rate brain membranes, while the nontremorgenic verruculotoxin had no effect. Inhibition of [35S]TBPS binding by paspalinine was non-competitive. This suggests that tremorgenic mycotoxins inhibit GABA/sub A/ receptor function by binding close to the receptor's Cl- channel. On the voltage-operated Cl- channel, only high concentrations of verruculogen and verruculotoxin caused significant inhibition of the channel's binding of [35S]TBPS. The data suggest that the tremorgenic action of these mycotoxins may be due in part to their inhibition of GABA/sub A/ receptor function. 21 references, 4 figures, 2 tables

  20. Editing modifies the GABA(A) receptor subunit alpha3

    DEFF Research Database (Denmark)

    Ohlson, Johan; Pedersen, Jakob Skou; Haussler, David;

    2007-01-01

    to find selectively edited sites and combined it with bioinformatic techniques that find stem-loop structures suitable for editing. We present here the first verified editing candidate detected by this screening procedure. We show that Gabra-3, which codes for the alpha3 subunit of the GABA...

  1. Structure activity relationship of selective GABA uptake inhibitors

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Jørgensen, Lars; Madsen, Karsten K;

    2015-01-01

    A series of β-amino acids with lipophilic diaromatic side chain was synthesized and characterized pharmacologically on mouse γ-amino butyric acid (GABA) transporter subtypes mGAT1-4 in order to investigate structure activity relationships (SAR) for mGAT2 (corresponding to hBGT-1). Variation in the...

  2. STUDY OF PHENIBUT ANTIEDEMIC ACTION AND NEW GABA DERIVATIVES

    Directory of Open Access Journals (Sweden)

    T. N. Scherbakova

    2015-01-01

    Full Text Available We have studied phenibut, gammalone, and new GABA derivatives action on the development of experimental cerebral edema. We have detected gammoxyn - the most prospective substance for further study as cere-broprotector. We have established that gammoxyn has a signified protective action in cerebral edema.

  3. STUDY OF PHENIBUT ANTIEDEMIC ACTION AND NEW GABA DERIVATIVES

    OpenAIRE

    T. N. Scherbakova; P. A. Ozerova

    2015-01-01

    We have studied phenibut, gammalone, and new GABA derivatives action on the development of experimental cerebral edema. We have detected gammoxyn - the most prospective substance for further study as cere-broprotector. We have established that gammoxyn has a signified protective action in cerebral edema.

  4. Role of proline and GABA in sexual reproduction of angiosperms.

    Science.gov (United States)

    Biancucci, Marco; Mattioli, Roberto; Forlani, Giuseppe; Funck, Dietmar; Costantino, Paolo; Trovato, Maurizio

    2015-01-01

    Two glutamate derivatives, proline and γ-aminobutyric acid (GABA), appear to play pivotal roles in different aspects of sexual reproduction in angiosperms, although their precise function in plant reproduction and the molecular basis of their action are not yet fully understood. Proline and GABA have long been regarded as pivotal amino acids in pollen vitality and fertility. Proline may constitute up to 70% of the free amino acid pool in pollen grains and it has been recently shown that Arabidopsis mutants affected in the first and rate-limiting step in proline synthesis produce aberrant and infertile pollen grains, indicating that proline synthesis is required for pollen development and fertility. Concerning GABA, a large body of evidence points to this glutamate derivative as a key determinant of post-pollination fertilization. Intriguingly, proline has also been associated with pollination, another aspect of sexual reproduction, since honeybees were reported to show a strong preference for proline-enriched nectars. In this review, we survey current knowledge on the roles of proline and GABA in plant fertility, and discuss future perspectives potentially capable to improve our understanding on the functions of these amino acids in pollen development, pollination, and pollen tube guidance. PMID:26388884

  5. Acute desensitization of presynaptic GABA(B)-mediated inhibition and induction of epileptiform discharges in the neonatal rat hippocampus

    NARCIS (Netherlands)

    Tosetti, P; Bakels, R; Colin-Le Brun, [No Value; Ferrand, N; Gaiarsa, JL; Caillard, O

    2004-01-01

    The consequences of sustained activation of GABA(B) receptors on GABA(B)-mediated inhibition and network activity were investigated in the neonatal rat hippocampus using whole-cell and extracellular field recordings. GABA(B)-mediated presynaptic control of gamma-aminobutyric acid (GABA) release prog

  6. GABA (γ-aminobutyric acid production, antioxidant activity in some germinated dietary seeds and the effect of cooking on their GABA content

    Directory of Open Access Journals (Sweden)

    Kasarin TIANSAWANG

    2016-01-01

    Full Text Available Abstract Germinated grains have been known as sources of Gamma-aminobutyric acid (GABA that provide beneficial effects for human health. This study was aimed to investigate GABA production, dietary fiber, antioxidant activity, and the effect of cooking on GABA loss in germinated legumes and sesame. The highest GABA content was found in germinated mung bean, (0.8068 g kg-1, 24 h incubation followed by germinated soybean, germinated black bean and soaked sesame. Beside GABA, dietary fiber content also increased in all grains during germination where the insoluble dietary fiber fractions were always found in higher proportions to soluble dietary fiber fractions. Our results also confirmed that germinated mung bean is a rich source of GABA and dietary fibers. Microwave cooking resulted in the smallest loss of GABA in mung bean and sesame, while steaming led to the least GABA content loss in soybean and black bean. Therefore microwave cooking and steaming are the most recommended cooking processes to preserve GABA in germinated legumes and sesame.

  7. Cloning and characterization of a functional human ¿-aminobutyric acid (GABA) transporter, human GAT-2

    DEFF Research Database (Denmark)

    Christiansen, Bolette; Meinild, Anne-Kristine; Jensen, Anders A.;

    2007-01-01

    aim of this study therefore was to search for this fourth missing human transporter. Using a bioinformatics approach, we successfully identified and cloned the full-length cDNA of a so far uncharacterized human GABA transporter (GAT). The predicted protein displays high sequence similarity to rat GAT...... dependent on both Na(+) and Cl(-). Pharmacologically the transporter is distinct from the other human GABA transporters and similar to rat GAT-2 and mouse GAT3 with high sensitivity toward GABA and beta-alanine. Furthermore the GABA transport inhibitor (S)-SNAP-5114 displayed some inhibitory activity at the......Plasma membrane gamma-aminobutyric acid (GABA) transporters act to terminate GABA neurotransmission in the mammalian brain. Intriguingly four distinct GABA transporters have been cloned from rat and mouse, whereas only three functional homologs of these transporters have been cloned from human. The...

  8. Are presynaptic GABA-Cρ2 receptors involved in anti-nociception?

    Science.gov (United States)

    Tadavarty, R; Hwang, J; Rajput, P S; Soja, P J; Kumar, U; Sastry, B R

    2015-10-01

    We investigated the anti-nociceptive effects of GABA-C receptors in the central nervous system. Intracisternal injection of CACA, a GABA-C receptor agonist or isoguvacine, a GABA-A receptor agonist, significantly increased the tail-withdrawal latency. TPMPA, a GABA-C receptor antagonist blocked the effects of CACA but not isoguvacine indicating that GABA-C receptors are involved in regulating pain. Further, double-labelled immunofluorescence studies revealed that GABA-Cρ2 receptors are expressed presynaptically in the spinal dorsal horn, especially, substantia gelatinosa, a region that has been previously implicated in analgesia by regulating nociceptive inflow. These data provide a provenance for future work looking at presynaptic spinal GABA-C receptors in the control of nociception. PMID:26327143

  9. The role of GABA in the regulation of GnRH neurons

    Directory of Open Access Journals (Sweden)

    Miho eWatanabe

    2014-11-01

    Full Text Available Gonadotropin-releasing hormone (GnRH neurons form the final common pathway for the central regulation of reproduction. Gamma-amino butyric acid (GABA has long been implicated as one of the major players in the regulation of GnRH neurons. Although GABA is typically an inhibitory neurotransmitter in the mature adult central nervous system, most mature GnRH neurons show the unusual characteristic of being excited by GABA. While many reports have provided much insight into the contribution of GABA to the activity of GnRH neurons, the precise physiological role of the excitatory action of GABA on GnRH neurons remains elusive. This brief review presents the current knowledge of the role of GABA signaling in GnRH neuronal activity. We also discuss the modulation of GABA signaling by neurotransmitters and neuromodulators and the functional consequence of GABAergic inputs to GnRH neurons in both the physiology and pathology of reproduction.

  10. Disentangling the responses of boreal stream assemblages to low stressor levels of diffuse pollution and altered channel morphology.

    Science.gov (United States)

    Turunen, Jarno; Muotka, Timo; Vuori, Kari-Matti; Karjalainen, Satu Maaria; Rääpysjärvi, Jaana; Sutela, Tapio; Aroviita, Jukka

    2016-02-15

    Non-point diffuse pollution from land use and alteration of hydromorphology are among the most detrimental stressors to stream ecosystems. We explored the independent and interactive effects of morphological channel alteration (channelization for water transport of timber) and diffuse pollution on species richness and community structure of four organism groups in boreal streams: diatoms, macrophytes, macroinvertebrates, and fish. Furthermore, the effect of these stressors on stream condition was evaluated by Ecological Quality Ratios (EQR) from the national Water Framework Directive (WFD) assessment system. We grouped 91 study sites into four groups that were impacted by either diffuse pollution or hydromorphological alteration, by both stressors, or by neither one. Macroinvertebrate richness was reduced by diffuse pollution, whereas other biological groups were unaltered. Hydromorphological modification had no effect on taxon richness of any of the assemblages. Community structure of all groups was significantly affected by diffuse pollution but not by hydromorphology. Similarly, EQRs indicated negative response by diatoms, macroinvertebrates and fish to diffuse pollution, but not to hydromorphological alteration. Agricultural diffuse pollution thus affected species identities and abundances rather than taxonomic richness. Our results suggest that channelization of boreal streams for timber transport has not altered hydromorphological conditions sufficiently to have a strong impact on stream biota, whereas even moderate nutrient enrichment may be ecologically harmful. Controlling diffuse pollution and associated land use stressors should be prioritized over restoration of in-stream habitat structure to improve the ecological condition of boreal streams. PMID:26706766

  11. Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex.

    Directory of Open Access Journals (Sweden)

    Susanna A Walter

    Full Text Available Knowledge about the neural underpinnings of the negative blood oxygen level dependent (BOLD responses in functional magnetic resonance imaging (fMRI is still limited. We hypothesized that pharmacological GABAergic modulation attenuates BOLD responses, and that blood concentrations of a positive allosteric modulator of GABA correlate inversely with BOLD responses in the cingulate cortex. We investigated whether or not pure task-related negative BOLD responses were co-localized with pharmacologically modulated BOLD responses. Twenty healthy adults received either 5 mg diazepam or placebo in a double blind, randomized design. During fMRI the subjects performed a working memory task. Results showed that BOLD responses in the cingulate cortex were inversely correlated with diazepam blood concentrations; that is, the higher the blood diazepam concentration, the lower the BOLD response. This inverse correlation was most pronounced in the pregenual anterior cingulate cortex and the anterior mid-cingulate cortex. For subjects with diazepam plasma concentration > 0.1 mg/L we observed negative BOLD responses with respect to fixation baseline. There was minor overlap between cingulate regions with task-related negative BOLD responses and regions where the BOLD responses were inversely correlated with diazepam concentration. We interpret that the inverse correlation between the BOLD response and diazepam was caused by GABA-related neural inhibition. Thus, this study supports the hypothesis that GABA attenuates BOLD responses in fMRI. The minimal overlap between task-related negative BOLD responses and responses attenuated by diazepam suggests that these responses might be caused by different mechanisms.

  12. An autonomous circadian clock in the inner mouse retina regulated by dopamine and GABA.

    Directory of Open Access Journals (Sweden)

    Guo-Xiang Ruan

    2008-10-01

    Full Text Available The influence of the mammalian retinal circadian clock on retinal physiology and function is widely recognized, yet the cellular elements and neural regulation of retinal circadian pacemaking remain unclear due to the challenge of long-term culture of adult mammalian retina and the lack of an ideal experimental measure of the retinal circadian clock. In the current study, we developed a protocol for long-term culture of intact mouse retinas, which allows retinal circadian rhythms to be monitored in real time as luminescence rhythms from a PERIOD2::LUCIFERASE (PER2::LUC clock gene reporter. With this in vitro assay, we studied the characteristics and location within the retina of circadian PER2::LUC rhythms, the influence of major retinal neurotransmitters, and the resetting of the retinal circadian clock by light. Retinal PER2::LUC rhythms were routinely measured from whole-mount retinal explants for 10 d and for up to 30 d. Imaging of vertical retinal slices demonstrated that the rhythmic luminescence signals were concentrated in the inner nuclear layer. Interruption of cell communication via the major neurotransmitter systems of photoreceptors and ganglion cells (melatonin and glutamate and the inner nuclear layer (dopamine, acetylcholine, GABA, glycine, and glutamate did not disrupt generation of retinal circadian PER2::LUC rhythms, nor did interruption of intercellular communication through sodium-dependent action potentials or connexin 36 (cx36-containing gap junctions, indicating that PER2::LUC rhythms generation in the inner nuclear layer is likely cell autonomous. However, dopamine, acting through D1 receptors, and GABA, acting through membrane hyperpolarization and casein kinase, set the phase and amplitude of retinal PER2::LUC rhythms, respectively. Light pulses reset the phase of the in vitro retinal oscillator and dopamine D1 receptor antagonists attenuated these phase shifts. Thus, dopamine and GABA act at the molecular level of PER

  13. Cell-attached recordings of responses evoked by photorelease of GABA in the immature cortical neurons

    Directory of Open Access Journals (Sweden)

    Guzel Valeeva

    2013-05-01

    Full Text Available We present a novel non-invasive technique to measure the polarity of GABAergic responses based on cell-attached recordings of currents activated by laser-uncaging of GABA. For these recordings, a patch pipette was filled with a solution containing RuBi-GABA, and GABA was released from this complex by a laser beam conducted to the tip of the patch pipette via an optic fiber. In cell-attached recordings from neocortical and hippocampal neurons in postnatal days P2-5 rat brain slices in vitro, we found that laser-uncaging of GABA activates integral cell-attached currents mediated by tens of GABA(A channels. The initial response was inwardly directed, indicating a depolarizing response to GABA. The direction of the initial response was dependent on the pipette potential and analysis of its slope-voltage relationships revealed a depolarizing driving force of +11 mV for the currents through GABA channels. Initial depolarizing responses to GABA uncaging were inverted to hyperpolarizing in the presence of the NKCC1 blocker bumetanide. Current-voltage relationships of the currents evoked by Rubi-GABA uncaging using voltage-ramps at the peak of responses not only revealed a bumetanide-sensitive depolarizing reversal potential of the GABA(A receptor mediated responses, but also showed a strong voltage-dependent hysteresis. Upon desensitization of the uncaged-GABA response, current-voltage relationships of the currents through single GABA(A channels revealed depolarizing responses with the driving force values similar to those obtained for the initial response. Thus, cell-attached recordings of the responses evoked by local intrapipette GABA uncaging are suitable to assess the polarity of the GABA(A-Rs mediated signals in small cell compartments.

  14. GABA increases electrical excitability in a subset of human unmyelinated peripheral axons.

    Directory of Open Access Journals (Sweden)

    Richard W Carr

    Full Text Available BACKGROUND: A proportion of small diameter primary sensory neurones innervating human skin are chemosensitive. They respond in a receptor dependent manner to chemical mediators of inflammation as well as naturally occurring algogens, thermogens and pruritogens. The neurotransmitter GABA is interesting in this respect because in animal models of neuropathic pain GABA pre-synaptically regulates nociceptive input to the spinal cord. However, the effect of GABA on human peripheral unmyelinated axons has not been established. METHODOLOGY/PRINCIPAL FINDINGS: Electrical stimulation was used to assess the effect of GABA on the electrical excitability of unmyelinated axons in isolated fascicles of human sural nerve. GABA (0.1-100 microM increased electrical excitability in a subset (ca. 40% of C-fibres in human sural nerve fascicles suggesting that axonal GABA sensitivity is selectively restricted to a sub-population of human unmyelinated axons. The effects of GABA were mediated by GABA(A receptors, being mimicked by bath application of the GABA(A agonist muscimol (0.1-30 microM while the GABA(B agonist baclofen (10-30 microM was without effect. Increases in excitability produced by GABA (10-30 microM were blocked by the GABA(A antagonists gabazine (10-20 microM, bicuculline (10-20 microM and picrotoxin (10-20 microM. CONCLUSIONS/SIGNIFICANCE: Functional GABA(A receptors are present on a subset of unmyelinated primary afferents in humans and their activation depolarizes these axons, an effect likely due to an elevated intra-axonal chloride concentration. GABA(A receptor modulation may therefore regulate segmental and peripheral components of nociception.

  15. Alterations in the Masseter Muscle and Plasma IL-6 Level Following Experimentally Induced Occlusal Interference and Chronic Stress – A Study in Rats

    OpenAIRE

    Simonić-Kocijan, Sunčana; Uhač, Ivone; Tariba, Petra; Fugošić, Vesna; Kovačević Pavičić, Daniela; Lajnert, Vlatka; Braut, Vedrana

    2012-01-01

    This study was undertaken to examine the alteration of masseter and plasma interleukin-6 after inducing occlusal interference and chronic stress. Male Wistar rats were submitted to chronic stress procedure, exposed to occlusal interference, or exposed to both mentioned procedures. Whole blood and masseter tissue were collected to determine interleukin-6 level, measured by means of ELISA. Masseter pain was evaluated using the orofacial formalin test. Masseter interleukin- 6 level w...

  16. Current Perspective on the Location and Function of Gamma- Aminobutyric Acid (GABA) and its Metabolic Partners in the Kidney.

    OpenAIRE

    Dunn, Kadeshia; Peppiatt-Wildman, Claire M.; Kelley, Stephen P; Wildman, Scott S.P.

    2014-01-01

    Abstract: Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter located in the mammalian central nervous system, which binds to GABAA and GABAB receptors to mediate its neurological effects. In addition to its role in the CNS, an increasing number of publications have suggested that GABA might also play a role in the regulation of renal function. All three enzymes associated with GABA metabolism; glutamic acid decarboxylase, GABA α-oxoglutarate transaminase (GABA-T) and succinic se...

  17. Alterations in Circulating miRNA Levels following Early-Stage Estrogen Receptor-Positive Breast Cancer Resection in Post-Menopausal Women

    DEFF Research Database (Denmark)

    Kodahl, Annette R; Zeuthen, Pernille; Binder, Harald; Knoop, Ann S; Ditzel, Henrik J

    2014-01-01

    alterations were also observed in an independent data set. METHODS: Global miRNA analysis was performed on prospectively collected serum samples from 24 post-menopausal women with estrogen receptor-positive early-stage breast cancer before surgery and 3 weeks after tumor resection using global LNA...... design and the same qPCR profiling platform, resulting in limited agreement. CONCLUSIONS: A panel of 4 circulating miRNAs exhibited significantly altered levels following radical resection of primary ER+ breast cancers in post-menopausal women. These specific miRNAs may be involved in tumorigenesis and...

  18. GABA-Synthesizing Enzymes in Calbindin and Calretinin Neurons in Monkey Prefrontal Cortex.

    Science.gov (United States)

    Rocco, Brad R; Sweet, Robert A; Lewis, David A; Fish, Kenneth N

    2016-05-01

    Non-overlapping groups of cortical γ-aminobutyric acid-releasing (GABAergic) neurons are identifiable by the presence of calbindin (CB), calretinin (CR), or parvalbumin (PV). Boutons from PV neuron subtypes are also distinguishable by differences in protein levels of the GABA-synthesizing enzymes GAD65 and GAD67. Multilabel fluorescence microscopy was used to determine if this diversity extends to boutons of CB and CR neurons in monkey prefrontal cortex. CB and CR neurons gave rise to 3 subpopulations of GAD-containing boutons: GAD65+, GAD67+, and GAD65/GAD67+. Somatostatin and vasoactive intestinal peptide-expressing neurons, subtypes of CB and CR neurons, respectively, also gave rise to these distinct bouton subpopulations. At the transcript level, CB and CR neurons contained mRNA encoding GAD67-only or both GADs. Thus, the distinct subpopulations of CB/GAD+ and CR/GAD+ boutons arise from 2 unique subtypes of CB and CR neurons. The different CB and CR GAD-expressing neurons targeted the same projection neurons and neuronal structures immunoreactive for PV, CR, or CB. These findings suggest that GABA synthesis from CB/GAD67+ and CR/GAD67+ neurons would presumably be more vulnerable to disease-associated deficits in GAD67 expression, such as in schizophrenia, than neurons that also contain GAD65. PMID:25824535

  19. Plant GABA:proline ratio modulates dissemination of the virulence Ti plasmid within the Agrobacterium tumefaciens hosted population.

    Science.gov (United States)

    Lang, Julien; Faure, Denis

    2016-05-01

    Accumulation of amino acids is a common plant response to several biotic and abiotic stresses, even if the roles of these accumulations remain often poorly understood. In a recent study we measured the levels of different amino acids in tumors of Arabidopsis thaliana induced by the phytopathogen Agrobacterium tumefaciens and correlated these data with changes of gene expressions in both organisms. This led to the demonstration that the non-protein amino acid GABA plays an important role for the adaptation of the bacteria to the plant tumor environment, and especially in the control of the virulent Ti plasmid dissemination. Here we present a model that describes how different GABA:proline ratios in the A. thaliana host may have different impacts on the conjugation of A. tumefaciens Ti plasmid, and advance the view that the amino acid metabolism of plant hosts could be critical for the propagation of the virulence genes in A. tumefaciens populations. PMID:27110651

  20. Hyperglycosylation and reduced GABA currents of mutated GABRB3 polypeptide in remitting childhood absence epilepsy.

    Science.gov (United States)

    Tanaka, Miyabi; Olsen, Richard W; Medina, Marco T; Schwartz, Emily; Alonso, Maria Elisa; Duron, Reyna M; Castro-Ortega, Ramon; Martinez-Juarez, Iris E; Pascual-Castroviejo, Ignacio; Machado-Salas, Jesus; Silva, Rene; Bailey, Julia N; Bai, Dongsheng; Ochoa, Adriana; Jara-Prado, Aurelio; Pineda, Gregorio; Macdonald, Robert L; Delgado-Escueta, Antonio V

    2008-06-01

    Childhood absence epilepsy (CAE) accounts for 10% to 12% of epilepsy in children under 16 years of age. We screened for mutations in the GABA(A) receptor (GABAR) beta 3 subunit gene (GABRB3) in 48 probands and families with remitting CAE. We found that four out of 48 families (8%) had mutations in GABRB3. One heterozygous missense mutation (P11S) in exon 1a segregated with four CAE-affected persons in one multiplex, two-generation Mexican family. P11S was also found in a singleton from Mexico. Another heterozygous missense mutation (S15F) was present in a singleton from Honduras. An exon 2 heterozygous missense mutation (G32R) was present in two CAE-affected persons and two persons affected with EEG-recorded spike and/or sharp wave in a two-generation Honduran family. All mutations were absent in 630 controls. We studied functions and possible pathogenicity by expressing mutations in HeLa cells with the use of Western blots and an in vitro translation and translocation system. Expression levels did not differ from those of controls, but all mutations showed hyperglycosylation in the in vitro translation and translocation system with canine microsomes. Functional analysis of human GABA(A) receptors (alpha 1 beta 3-v2 gamma 2S, alpha 1 beta 3-v2[P11S]gamma 2S, alpha 1 beta 3-v2[S15F]gamma 2S, and alpha 1 beta 3-v2[G32R]gamma 2S) transiently expressed in HEK293T cells with the use of rapid agonist application showed that each amino acid transversion in the beta 3-v2 subunit (P11S, S15F, and G32R) reduced GABA-evoked current density from whole cells. Mutated beta 3 subunit protein could thus cause absence seizures through a gain in glycosylation of mutated exon 1a and exon 2, affecting maturation and trafficking of GABAR from endoplasmic reticulum to cell surface and resulting in reduced GABA-evoked currents. PMID:18514161

  1. Brain γ-aminobutyric acid (GABA) detection in vivo with the J-editing (1) H MRS technique: a comprehensive methodological evaluation of sensitivity enhancement, macromolecule contamination and test-retest reliability.

    Science.gov (United States)

    Shungu, Dikoma C; Mao, Xiangling; Gonzales, Robyn; Soones, Tacara N; Dyke, Jonathan P; van der Veen, Jan Willem; Kegeles, Lawrence S

    2016-07-01

    Abnormalities in brain γ-aminobutyric acid (GABA) have been implicated in various neuropsychiatric and neurological disorders. However, in vivo GABA detection by (1) H MRS presents significant challenges arising from the low brain concentration, overlap by much stronger resonances and contamination by mobile macromolecule (MM) signals. This study addresses these impediments to reliable brain GABA detection with the J-editing difference technique on a 3-T MR system in healthy human subjects by: (i) assessing the sensitivity gains attainable with an eight-channel phased-array head coil; (ii) determining the magnitude and anatomic variation of the contamination of GABA by MM; and (iii) estimating the test-retest reliability of the measurement of GABA with this method. Sensitivity gains and test-retest reliability were examined in the dorsolateral prefrontal cortex (DLPFC), whereas MM levels were compared across three cortical regions: DLPFC, the medial prefrontal cortex (MPFC) and the occipital cortex (OCC). A three-fold higher GABA detection sensitivity was attained with the eight-channel head coil compared with the standard single-channel head coil in DLPFC. Despite significant anatomical variation in GABA + MM and MM across the three brain regions (p correlation coefficient of test vs. retest for GABA/W was 0.98 (R(2)  = 0.96, p = 0.0007), the percentage coefficient of variation (CV) was 1.25% and the intraclass correlation coefficient (ICC) was 0.98. Similar reliability was also found for the co-edited resonance of combined glutamate and glutamine (Glx) for both coils. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27173449

  2. A longitudinal study of alterations of hippocampal volumes and serum BDNF levels in association to atypical antipsychotics in a sample of first-episode patients with schizophrenia.

    Directory of Open Access Journals (Sweden)

    Emmanouil Rizos

    Full Text Available BACKGROUND: Schizophrenia is associated with structural and functional abnormalities of the hippocampus, which have been suggested to play an important role in the formation and emergence of schizophrenia syndrome. Patients with schizophrenia exhibit significant bilateral hippocampal volume reduction and progressive hippocampal volume decrease in first-episode patients with schizophrenia has been shown in many neuroimaging studies. Dysfunction of the neurotrophic system has been implicated in the pathophysiology of schizophrenia. The initiation of antipsychotic medication alters the levels of serum Brain Derived Neurotrophic Factor (BDNF levels. However it is unclear whether treatment with antipsychotics is associated with alterations of hippocampal volume and BDNF levels. METHODS: In the present longitudinal study we investigated the association between serum BDNF levels and hippocampal volumes in a sample of fourteen first-episode drug-naïve patients with schizophrenia (FEP. MRI scans, BDNF and clinical measurements were performed twice: at baseline before the initiation of antipsychotic treatment and 8 months later, while the patients were receiving monotherapy with second generation antipsychotics (SGAs. RESULTS: We found that left hippocampal volume was decreased (corrected left HV [t = 2.977, df = 13, p = .011] at follow-up; We also found that the higher the BDNF levels change the higher were the differences of corrected left hippocampus after 8 months of treatment with atypical antipsychotics (Pearson r = 0.597, p = 0.024. CONCLUSIONS: The association of BDNF with hippocampal volume alterations in schizophrenia merits further investigation and replication in larger longitudinal studies.

  3. GABA transporters control GABAergic neurotransmission in the mouse subplate.

    Science.gov (United States)

    Unichenko, P; Kirischuk, S; Luhmann, H J

    2015-09-24

    The subplate is a transient layer between the cortical plate and intermediate zone in the developing cortex. Thalamo-cortical axons form temporary synapses on subplate neurons (SPns) before invading the cortical plate. Neuronal activity within the subplate is of critical importance for the development of neocortical circuits and architecture. Although both glutamatergic and GABAergic inputs on SPns were reported, short-term plasticity of GABAergic transmission has not been investigated yet. GABAergic postsynaptic currents (GPSCs) were recorded from SPns in coronal neocortical slices prepared from postnatal day 3-4 mice using whole-cell patch-clamp technique. Evoked GPSCs (eGPSCs) elicited by electrical paired-pulse stimulation demonstrated paired-pulse depression at all interstimulus intervals tested. Baclofen, a specific GABAB receptor (GABABR) agonist, reduced eGPSC amplitudes and increased paired-pulse ratio (PPR), suggesting presynaptic location of functional GABABRs. Baclofen-induced effects were alleviated by (2S)-3-[[(1S)-1-(3,4-dichlorophenyl)ethyl]amino-2-hydroxypropyl](phenylmethyl)phosphinic acid (CGP55845), a selective GABABR blocker. Moreover, CGP55845 increased eGPSC amplitudes and decreased PPR even under control conditions, indicating that GABABRs are tonically activated by ambient GABA. Because extracellular GABA concentration is mainly regulated by GABA transporters (GATs), we asked whether GATs release GABA. 1,2,5,6-tetrahydro-1-[2-[[(diphenylmethylene)amino]oxy]ethyl]-3-pyridinecarboxylic acid (NNC-711) (10μM), a selective GAT-1 blocker, increased eGPSC decay time, decreased eGPSC amplitudes and PPR. The two last effects but not the first one were blocked by CGP55845, indicating that GAT-1 blockade causes an elevation of extracellular GABA concentration and in turn activation of extrasynaptic GABAARs and presynaptic GABABRs. 1-[2-[tris(4-methoxyphenyl)methoxy]ethyl]-(S)-3-piperidinecarboxylic acid (SNAP-5114), a specific GAT-2/3 blocker, failed

  4. Ethanol enhances GABA-induced 36Cl-influx in primary spinal cord cultured neurons

    International Nuclear Information System (INIS)

    Ethanol has a pharmacological profile similar to other centrally acting drugs, which facilitate GABAergic transmission. GABA is known to produce its effects by increasing the conductance to Cl- ions. In this study, we have examined the effect of ethanol on GABA-induced 36Cl-influx in primary spinal cord cultured neurons. GABA produces a concentration-dependent, and saturable effect on 36Cl-influx in these neurons. Ethanol potentiates the effect of GABA on 36Cl-influx in these neurons. GABA (20 microM) increased the 36Cl-influx by 75% over the basal value, and in the presence of 50 mM ethanol, the observed increase was 142%. Eadie-Hoffstee analysis of the saturation curves indicated that ethanol decreases the Km value of GABA (10.6 microM to 4.2 microM), and also increases the Vmax. Besides potentiating the effect of GABA, ethanol also appears to have a direct effect in the absence of added GABA. These results suggest that ethanol enhances GABA-induced 36Cl-influx and indicate a role of GABAergic system in the actions of ethanol. These results also support the behavioral and electrophysiological studies, which have implicated GABA systems in the actions of ethanol. The potential mechanism(s) and the role of direct effect of ethanol is not clear at this time, but is currently being investigated

  5. Reductions in Frontocortical Cytokine Levels are Associated with Long-Lasting Alterations in Reward Valuation after Methamphetamine

    OpenAIRE

    Stolyarova, Alexandra; Thompson, Andrew B.; Barrientos, Ruth M.; Izquierdo, Alicia

    2014-01-01

    Alterations in reward valuation are thought to have a central role at all stages of the addiction process. We previously reported work aversion in an effortful T-maze task following a binge exposure to methamphetamine, and no such changes in effort following escalating doses. Limitations of the T-maze task include its two available options, with an effort requirement, in the form of increasing barrier height, varying incrementally as a function of time, and reward magnitudes held constant. Re...

  6. Modulation of Glucose Transporter 1 (GLUT1) Expression Levels Alters Mouse Mammary Tumor Cell Growth In Vitro and In Vivo

    OpenAIRE

    Young, Christian D.; Lewis, Andrew S; Rudolph, Michael C; Ruehle, Marisa D; Jackman, Matthew R.; Yun, Ui J.; Ilkun, Olesya; Pereira, Renata; Abel, E. Dale; Anderson, Steven M.

    2011-01-01

    Tumor cells exhibit an altered metabolism characterized by elevated aerobic glycolysis and lactate secretion which is supported by an increase in glucose transport and consumption. We hypothesized that reducing or eliminating the expression of the most prominently expressed glucose transporter(s) would decrease the amount of glucose available to breast cancer cells thereby decreasing their metabolic capacity and proliferative potential. Of the 12 GLUT family glucose transporters expressed in ...

  7. Melanogenesis stimulation in B16-F10 melanoma cells induces cell cycle alterations, increased ROS levels and a differential expression of proteins as revealed by proteomic analysis

    International Nuclear Information System (INIS)

    Considering that stimulation of melanogenesis may lead to alterations of cellular responses, besides melanin production, our main goal was to study the cellular effects of melanogenesis stimulation of B16-F10 melanoma cells. Our results show increased levels of the reactive oxygen species after 15 h of melanogenesis stimulation. Following 48 h of melanogenesis stimulation, proliferation was inhibited (by induction of cell cycle arrest in the G1 phase) and the expression levels of p21 mRNA were increased. In addition, melanogenesis stimulation did not induce cellular senescence. Proteomic analysis demonstrated the involvement of proteins from other pathways besides those related to the cell cycle, including protein disulfide isomerase A3, heat-shock protein 70, and fructose biphosphate aldolase A (all up-regulated), and lactate dehydrogenase (down-regulated). In RT-qPCR experiments, the levels of pyruvate kinase M2 mRNA dropped, whereas the levels of ATP synthase (beta-F1) mRNA increased. These data indicate that melanogenesis stimulation of B16-F10 cells leads to alterations in metabolism and cell cycle progression that may contribute to an induction of cell quiescence, which may provide a mechanism of resistance against cellular injury promoted by melanin synthesis. -- Highlights: ► Melanogenesis stimulation by L-tyrosine+NH4Cl in B16-F10 melanoma cells increases ROS levels. ► Melanogenesis inhibits cell proliferation, and induced cell cycle arrest in the G1 phase. ► Proteomic analysis showed alterations in proteins of the cell cycle and glucose metabolism. ► RT-qPCR analysis confirmed alterations of metabolic targets after melanogenesis stimulation.

  8. Melanogenesis stimulation in B16-F10 melanoma cells induces cell cycle alterations, increased ROS levels and a differential expression of proteins as revealed by proteomic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, Elizabeth S.; Kawahara, Rebeca [Departamento de Bioquimica e Biologia Molecular, Setor de Ciencias Biologicas, Universidade Federal do Parana, P.O. Box 19046, CEP 81531-990, Curitiba, PR (Brazil); Kadowaki, Marina K. [Universidade Estadual do Oeste do Parana, Cascavel, PR (Brazil); Amstalden, Hudson G.; Noleto, Guilhermina R.; Cadena, Silvia Maria S.C.; Winnischofer, Sheila M.B. [Departamento de Bioquimica e Biologia Molecular, Setor de Ciencias Biologicas, Universidade Federal do Parana, P.O. Box 19046, CEP 81531-990, Curitiba, PR (Brazil); Martinez, Glaucia R., E-mail: grmartinez@ufpr.br [Departamento de Bioquimica e Biologia Molecular, Setor de Ciencias Biologicas, Universidade Federal do Parana, P.O. Box 19046, CEP 81531-990, Curitiba, PR (Brazil)

    2012-09-10

    Considering that stimulation of melanogenesis may lead to alterations of cellular responses, besides melanin production, our main goal was to study the cellular effects of melanogenesis stimulation of B16-F10 melanoma cells. Our results show increased levels of the reactive oxygen species after 15 h of melanogenesis stimulation. Following 48 h of melanogenesis stimulation, proliferation was inhibited (by induction of cell cycle arrest in the G1 phase) and the expression levels of p21 mRNA were increased. In addition, melanogenesis stimulation did not induce cellular senescence. Proteomic analysis demonstrated the involvement of proteins from other pathways besides those related to the cell cycle, including protein disulfide isomerase A3, heat-shock protein 70, and fructose biphosphate aldolase A (all up-regulated), and lactate dehydrogenase (down-regulated). In RT-qPCR experiments, the levels of pyruvate kinase M2 mRNA dropped, whereas the levels of ATP synthase (beta-F1) mRNA increased. These data indicate that melanogenesis stimulation of B16-F10 cells leads to alterations in metabolism and cell cycle progression that may contribute to an induction of cell quiescence, which may provide a mechanism of resistance against cellular injury promoted by melanin synthesis. -- Highlights: Black-Right-Pointing-Pointer Melanogenesis stimulation by L-tyrosine+NH{sub 4}Cl in B16-F10 melanoma cells increases ROS levels. Black-Right-Pointing-Pointer Melanogenesis inhibits cell proliferation, and induced cell cycle arrest in the G1 phase. Black-Right-Pointing-Pointer Proteomic analysis showed alterations in proteins of the cell cycle and glucose metabolism. Black-Right-Pointing-Pointer RT-qPCR analysis confirmed alterations of metabolic targets after melanogenesis stimulation.

  9. The GABAB1a isoform mediates heterosynaptic depression at hippocampal mossy fiber synapses

    DEFF Research Database (Denmark)

    Guetg, Nicole; Seddik, Riad; Vigot, Réjan;

    2009-01-01

    GABA(B) receptor subtypes are based on the subunit isoforms GABA(B1a) and GABA(B1b), which associate with GABA(B2) subunits to form pharmacologically indistinguishable GABA(B(1a,2)) and GABA(B(1b,2)) receptors. Studies with mice selectively expressing GABA(B1a) or GABA(B1b) subunits revealed that...... GABA(B(1a,2)) receptors are more abundant than GABA(B(1b,2)) receptors at glutamatergic terminals. Accordingly, it was found that GABA(B(1a,2)) receptors are more efficient than GABA(B(1b,2)) receptors in inhibiting glutamate release when maximally activated by exogenous application of the agonist...... baclofen. Here, we used a combination of genetic, ultrastructural and electrophysiological approaches to analyze to what extent GABA(B(1a,2)) and GABA(B(1b,2)) receptors inhibit glutamate release in response to physiological activation. We first show that at hippocampal mossy fiber (MF)-CA3 pyramidal...

  10. Phenibut (beta-phenyl-GABA): a tranquilizer and nootropic drug.

    Science.gov (United States)

    Lapin, I

    2001-01-01

    Phenibut (beta-phenyl-gamma-aminobutyric acid HCl) is a neuropsychotropic drug that was discovered and introduced into clinical practice in Russia in the 1960s. It has anxiolytic and nootropic (cognition enhancing) effects. It acts as a GABA-mimetic, primarily at GABA(B) and, to some extent, at GABA(A) receptors. It also stimulates dopamine receptors and antagonizes beta-phenethylamine (PEA), a putative endogenous anxiogenic. The psychopharmacological activity of phenibut is similar to that of baclofen, a p-Cl-derivative of phenibut. This article reviews the structure-activity relationship of phenibut and its derivatives. Emphasis is placed on the importance of the position of the phenyl ring, the role of the carboxyl group, and the activity of optical isomers. Comparison of phenibut with piracetam and diazepam reveals similarities and differences in their pharmacological and clinical effects. Phenibut is widely used in Russia to relieve tension, anxiety, and fear, to improve sleep in psychosomatic or neurotic patients; as well as a pre- or post-operative medication. It is also used in the therapy of disorders characterized by asthenia and depression, as well as in post-traumatic stress, stuttering and vestibular disorders. PMID:11830761

  11. Aerobic bacterial microbiota of the conjunctiva in diabetic patients with normal and altered glycated hemoglobin levels in two regions in Brazil

    Directory of Open Access Journals (Sweden)

    Natalia Pimentel Moreno

    2014-12-01

    Full Text Available Purpose: To study the aerobic bacterial microbiota of the conjunctiva in diabetic patients with regard to the management of diabetes, assessed using glycated hemoglobin levels. Methods: A cross-sectional study was conducted using conjunctival smears of diabetic patients from both sexes and with different ages, residing in two different Brazilian cities (Sorocaba and Rio Branco. A control group of non-diabetic patients was also included. The diabetic patients were considered to have controlled diabetes when their glycated hemoglobin level was ≤7% and blood glucose level was ≤126 mg/dL. Patients with non-controlled diabetes were those with glycated hemoglobin levels >7% and blood glucose levels >126 mg/dL. The samples obtained were inoculated in Brain-Heart Infusion broth and in culture media for aerobic bacteria (blood and chocolate agars; bacterial growth was evaluated in a microbiology laboratory. Results: A total of 120 eyes of 120 patients were included in the present study. The percentage of cultures in which bacterial growth was observed was greater in diabetic patients, although the difference was not statistically significant (p=0.103. There was a greater trend toward bacterial growth in the conjunctiva of diabetic patients with altered fasting blood glucose. There was no difference in the frequency of bacterial growth on the conjunctiva between diabetic patients with normal or altered glycated hemoglobin levels. In Sorocaba, conjunctival bacterial growth was similar to that observed in Rio Branco. The microorganism most frequently detected in the present study was Staphylococcus epidermidis, followed by Staphylococcus aureus, Proteus mirabilis, and Escherichia coli. Conclusion: There was no difference between diabetic patients with normal or altered glycated hemoglobin levels. The microorganisms found were similar to those found in studies investigating the conjunctival bacterial flora of diabetic and non-diabetic patients.

  12. Fast detection of extrasynaptic GABA with a whole-cell sniffer

    DEFF Research Database (Denmark)

    Christensen, Rasmus K; Petersen, Anders V; Schmitt, Nicole;

    2014-01-01

    Gamma-amino-butyric acid (GABA) is the main inhibitory transmitter of the brain. It operates by binding to specific receptors located both inside and outside synapses. The extrasynaptic receptors are activated by spillover from GABAergic synapses and by ambient GABA in the extracellular space....... Ambient GABA is essential for adjusting the excitability of neurons. However, due to the lack of suitable methods, little is known about its dynamics. Here we describe a new technique that allows detection of GABA transients and measurement of the steady state GABA concentration with high spatial and...... temporal resolution. We used a human embryonic kidney (HEK) cell line that stably expresses GABAA receptors composed of α1, β2, and γ2 subunits. We recorded from such a HEK cell with the whole-cell patch-clamp technique. The presence of GABA near the HEK cell generated a measurable electric current whose...

  13. Prospective frequency correction for macromolecule-suppressed GABA editing at 3T

    DEFF Research Database (Denmark)

    Edden, Richard A E; Oeltzschner, Georg; Harris, Ashley D;

    2016-01-01

    PURPOSE: To investigate the effects of B0 field offsets and drift on macromolecule (MM)-suppressed GABA-editing experiments, and to implement and test a prospective correction scheme. "Symmetric" editing schemes are proposed to suppress unwanted coedited MM signals in GABA editing. MATERIALS AND...... METHODS: Full density-matrix simulations of both conventional (nonsymmetric) and symmetric MM-suppressed editing schemes were performed for the GABA spin system to evaluate their offset-dependence. Phantom and in vivo (15 subjects at 3T) GABA-edited experiments with symmetrical suppression of MM signals...... were performed to quantify the effects of field offsets on the total GABA+MM signal (designated GABA+). A prospective frequency correction method based on interleaved water referencing (IWR) acquisitions was implemented and its experimental performance evaluated during positive and negative drift...

  14. Positive modulation of delta-subunit containing GABAA receptors in mouse neurons

    DEFF Research Database (Denmark)

    Vardya, Irina; Hoestgaard-Jensen, Kirsten; Nieto-Gonzalez, Jose Luis;

    2012-01-01

    δ-subunit containing extrasynaptic GABA(A) receptors are potential targets for modifying neuronal activity in a range of brain disorders. With the aim of gaining more insight in synaptic and extrasynaptic inhibition, we used a new positive modulator, AA29504, of δ-subunit containing GABA(A) recep......δ-subunit containing extrasynaptic GABA(A) receptors are potential targets for modifying neuronal activity in a range of brain disorders. With the aim of gaining more insight in synaptic and extrasynaptic inhibition, we used a new positive modulator, AA29504, of δ-subunit containing GABA......-free environment using Ca²⁺ imaging in cultured neurons, AA29504 showed GABA(A) receptor agonism in the absence of agonist. Finally, AA29504 exerted dose-dependent stress-reducing and anxiolytic effects in mice in vivo. We propose that AA29504 potentiates δ-containing GABA(A) receptors to enhance tonic inhibition...

  15. Prenatal exposure to moderate levels of ethanol alters social behavior in adult rats: Relationship to structural plasticity and immediate early gene expression in frontal cortex

    OpenAIRE

    Derek A Hamilton; Akers, Katherine G.; Rice, James P.; Johnson, Travis E.; Candelaria-Cook, Felicha T.; Maes, Levi I.; Rosenberg, Martina; Valenzuela, C. Fernando; Savage, Daniel D.

    2009-01-01

    The goals of the present study were to characterize the effects of prenatal exposure to moderate levels of ethanol on adult social behavior, and to evaluate fetal-ethanol-related effects on dendritic morphology, structural plasticity and activity-related immediate early gene (IEG) expression in the agranular insular (AID) and prelimbic (Cg3) regions of frontal cortex. Baseline fetal-ethanol-related alterations in social behavior were limited to reductions in social investigation in males. Rep...

  16. Quantitative changes of GABA-immunoreactive cells in the hindlimb representation of the rat somatosensory cortex after 14-day hindlimb unloading by tail suspension

    Science.gov (United States)

    D'Amelio, F.; Fox, R. A.; Wu, L. C.; Daunton, N. G.

    1996-01-01

    The present study was aimed at evaluating quantitatively gamma-aminobutyric acid (GABA) immunoreactivity in the hindlimb representation of the rat somatosensory cortex after 14 days of hindlimb unloading by tail suspension. A reduction in the number of GABA-immunoreactive cells with respect to the control animals was observed in layer Va and Vb. GABA-containing terminals were also reduced in the same layers, particularly those terminals surrounding the soma and apical dendrites of pyramidal cells in layer Vb. On the basis of previous morphological and behavioral studies of the neuromuscular system of hindlimb-suspended animals, it is suggested that the unloading due to hindlimb suspension alters afferent signaling and feedback information from intramuscular receptors to the cerebral cortex due to modifications in the reflex organization of hindlimb muscle groups. We propose that the reduction in immunoreactivity of local circuit GABAergic neurons and terminals is an expression of changes in their modulatory activity to compensate for the alterations in the afferent information.

  17. Transgenic poplar expressing the pine GS1a show alterations in nitrogen homeostasis during drought.

    Science.gov (United States)

    Molina-Rueda, Juan Jesús; Kirby, Edward G

    2015-09-01

    Transgenic hybrid poplars engineered to express ectopically the heterologous pine cytosolic GS1a display a number of significant pleiotropic phenotypes including enhanced growth, enhanced nitrogen use efficiency, and resistance to drought stress. The present study was undertaken in order to assess mechanisms whereby ectopic expression of pine GS1a in transgenic poplars results in enhanced agronomic phenotypes. Microarray analysis using the Agilent Populus whole genome array has allowed identification of genes differentially expressed between wild type (WT) and GS transgenics in four tissues (sink leaves, source leaves, stems, and roots) under three growth conditions (well-watered, drought, and recovery). Analysis revealed that differentially expressed genes in functional categories related to nitrogen metabolism show a trend of significant down-regulation in GS poplars compared to the WT, including genes encoding nitrate and nitrite reductases. The down-regulation of these genes was verified using qPCR, and downstream effects were further tested using NR activity assays. Results suggest that higher glutamine levels in GS transgenics regulate nitrate uptake and reduction. Transcript levels of nitrogen-related genes in leaves, including GS/GOGAT cycle enzymes, aspartate aminotransferase, GABA shunt enzymes, photorespiration enzymes, asparagine synthetase, phenylalanine ammonia lyase, isocitrate dehydrogenase, and PII, were also assessed using qPCR revealing significant differences between GS poplars and the WT. Moreover, metabolites related to these differentially expressed genes showed alterations in levels, including higher levels of GABA, hydroxyproline, and putrescine in the GS transgenic. These alterations in nitrogen homeostasis offer insights into mechanisms accounting for drought tolerance observed in GS poplars. PMID:26113157

  18. Glutamate, GABA, and glutamine are synchronously upregulated in the mouse lateral septum during the postpartum period

    OpenAIRE

    Zhao, Changjiu; Gammie, Stephen C.

    2014-01-01

    Dramatic structural and functional remodeling occurs in the postpartum brain for the establishment of maternal care, which is essential for the growth and development of young offspring. Glutamate and GABA signaling are critically important in modulating multiple behavioral performances. Large scale signaling changes occur in the postpartum brain, but it is still not clear to what extent the neurotransmitters glutamate and GABA change and whether the ratio of glutamate/GABA remains balanced. ...

  19. Plasticity of GABA transporters: an unconventional route to shape inhibitory synaptic transmission

    OpenAIRE

    Annalisa eScimemi

    2014-01-01

    The brain relies on GABAergic neurons to control the ongoing activity of neuronal networks. GABAergic neurons control the firing pattern of excitatory cells, the temporal structure of membrane potential oscillations and the time window for integration of synaptic inputs. These actions require a fine control of the timing of GABA receptor activation which, in turn, depends on the precise timing of GABA release from pre-synaptic terminals and GABA clearance from the extracellular space. Extrace...

  20. Early depolarizing GABA controls critical period plasticity in the rat visual cortex

    OpenAIRE

    Deidda, Gabriele; Allegra, Manuela; Cerri, Chiara; Naskar, Shovan; Bony, Guillaume; Zunino, Giulia; Bozzi, Yuri; Caleo, Matteo; Cancedda, Laura

    2014-01-01

    SUMMARY Hyperpolarizing and inhibitory GABA regulates “critical periods” for plasticity in sensory cortices. Here, we examine the role of early, depolarizing GABA in controlling plasticity mechanisms. We report that brief interference with depolarizing GABA during early development prolonged critical period plasticity in visual cortical circuits, without affecting overall development of the visual system. The effects on plasticity were accompanied by dampened inhibitory neurotransmission, dow...

  1. Fast detection of extrasynaptic GABA with a whole-cell sniffer

    OpenAIRE

    Christensen, Rasmus K.; Petersen, Anders V.; Schmitt, Nicole; Perrier, Jean-François

    2014-01-01

    Gamma-amino-butyric acid (GABA) is the main inhibitory transmitter of the brain. It operates by binding to specific receptors located both inside and outside synapses. The extrasynaptic receptors are activated by spillover from GABAergic synapses and by ambient GABA in the extracellular space. Ambient GABA is essential for adjusting the excitability of neurons. However, due to the lack of suitable methods, little is known about its dynamics. Here we describe a new technique that allows detect...

  2. Neurotransmitters as food supplements: the effects of GABA on brain and behavior

    OpenAIRE

    Boonstra, Evert; de Kleijn, Roy; Colzato, Lorenza S; Alkemade, Anneke; Forstmann, Birte U.; Nieuwenhuis, Sander

    2015-01-01

    Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the human cortex. The food supplement version of GABA is widely available online. Although many consumers claim that they experience benefits from the use of these products, it is unclear whether these supplements confer benefits beyond a placebo effect. Currently, the mechanism of action behind these products is unknown. It has long been thought that GABA is unable to cross the blood–brain barrier (BBB), but the studie...

  3. Comparative Mapping of GABA-Immunoreactive Neurons in the Buccal Ganglia of Nudipleura Molluscs.

    Science.gov (United States)

    Gunaratne, Charuni A; Katz, Paul S

    2016-04-15

    Phylogenetic comparisons of neurotransmitter distribution are important for understanding the ground plan organization of nervous systems. This study describes the γ-aminobutyric acid (GABA)-immunoreactive (GABA-ir) neurons in the buccal ganglia of six sea slug species (Mollusca, Gastropoda, Euthyneura, Nudipleura). In the nudibranch species, Hermissenda crassicornis, Tritonia diomedea, Tochuina tetraquetra, and Dendronotus iris, the number of GABA-ir neurons was highly consistent. Another nudibranch, Melibe leonina, however, contained approximately half the number of GABA-ir neurons. This may relate to its loss of a radula and its unique feeding behavior. The GABA immunoreactivity in a sister group to the nudibranchs, Pleurobranchaea californica, differed drastically from that of the nudibranchs. Not only did it have significantly more GABA-ir neurons but it also had a unique GABA distribution pattern. Furthermore, unlike the nudibranchs, the Pleurobranchaea GABA distribution was also different from that of other, more distantly related, euopisthobranch and panpulmonate snails and slugs. This suggests that the Pleurobranchaea GABA distribution may be a derived feature, unique to this lineage. The majority of GABA-ir axons and neuropil in the Nudipleura were restricted to the buccal ganglia, commissures, and connectives. However, in Tritonia and Pleurobranchaea, we detected a few GABA-ir fibers in buccal nerves that innervate feeding muscles. Although the specific functions of the GABA-ir neurons in the species in this study are not known, the innervation pattern suggests these neurons may play an integrative or regulatory role in bilaterally coordinated behaviors in the Nudipleura. PMID:26355705

  4. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    Science.gov (United States)

    Geigerseder, Christof; Doepner, Richard FG; Thalhammer, Andrea; Krieger, Annette; Mayerhofer, Artur

    2004-01-01

    The neurotransmitter gamma-aminobutyric acid (GABA) and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD), as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA) we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment. PMID:15040802

  5. Stimulation of TM3 Leydig cell proliferation via GABAA receptors: A new role for testicular GABA

    Directory of Open Access Journals (Sweden)

    Krieger Annette

    2004-03-01

    Full Text Available Abstract The neurotransmitter gamma-aminobutyric acid (GABA and subtypes of GABA receptors were recently identified in adult testes. Since adult Leydig cells possess both the GABA biosynthetic enzyme glutamate decarboxylase (GAD, as well as GABAA and GABAB receptors, it is possible that GABA may act as auto-/paracrine molecule to regulate Leydig cell function. The present study was aimed to examine effects of GABA, which may include trophic action. This assumption is based on reports pinpointing GABA as regulator of proliferation and differentiation of developing neurons via GABAA receptors. Assuming such a role for the developing testis, we studied whether GABA synthesis and GABA receptors are already present in the postnatal testis, where fetal Leydig cells and, to a much greater extend, cells of the adult Leydig cell lineage proliferate. Immunohistochemistry, RT-PCR, Western blotting and a radioactive enzymatic GAD assay evidenced that fetal Leydig cells of five-six days old rats possess active GAD protein, and that both fetal Leydig cells and cells of the adult Leydig cell lineage possess GABAA receptor subunits. TM3 cells, a proliferating mouse Leydig cell line, which we showed to possess GABAA receptor subunits by RT-PCR, served to study effects of GABA on proliferation. Using a colorimetric proliferation assay and Western Blotting for proliferating cell nuclear antigen (PCNA we demonstrated that GABA or the GABAA agonist isoguvacine significantly increased TM3 cell number and PCNA content in TM3 cells. These effects were blocked by the GABAA antagonist bicuculline, implying a role for GABAA receptors. In conclusion, GABA increases proliferation of TM3 Leydig cells via GABAA receptor activation and proliferating Leydig cells in the postnatal rodent testis bear a GABAergic system. Thus testicular GABA may play an as yet unrecognized role in the development of Leydig cells during the differentiation of the testicular interstitial compartment.

  6. Natural analogue studies of long term alteration of volcanic glass under the high level radioactive waste disposal conditions. Document prepared by other institute, based on the trust contract

    International Nuclear Information System (INIS)

    The alteration characteristics of volcanic glass bentonite in geological medium are investigated as natural analogues of geological disposal of high-level radioactive wastes. For the study of alteration of volcanic glass, literature survey, petrographical observation by using optical microscope, chemical analysis of pore water and groundwater, and microbiostratigraphical study were carried out. The volcanic ashes were collected from a borehole, which had been drilled in the Kanto region by the National Research Institute for Earth Science and Disaster Prevention. The volcanic glass was wholly altered in thin sections. Chemical analysis of pore water indicate the chloride-rich composition. And chemical analysis of groundwater, which are pumped up near the studied borehole, indicate the mixing product of connate marine water and fresh groundwater. Fossil evidence suggests that the studied volcanic glass is 3.65 ∼ 4.2 Ma. in age, and is correlated with upper Miura Group. This study leads to following conclusion. The volcanic glass, under the temperature condition 70degC, was wholly altered to montomorillonite and clinoptilolite. This case must be occurred in the connate marine water at last 0.5 Ma.. (author)

  7. Role of GABA and GABAA Channels in T lymphocytes and Stem cells

    OpenAIRE

    Mendu, Suresh Kumar

    2012-01-01

    GABA (gamma-aminobutyric acid) is best known for its physiological function in the central nervous system.  In the brain GABA is the main inhibitory neurotransmitter where it decreases excitability of neurons and neuronal networks.  The balance between excitation evoked by glutamate and inhibition evoked by GABA is the base from where the brain works. It is fair to say that glutamate is like the gas-pedal and GABA the brake that keeps the brain running at a normal speed.  But, it is not only ...

  8. Distinct roles for GABA across multiple timescales in mammalian circadian timekeeping.

    Science.gov (United States)

    DeWoskin, Daniel; Myung, Jihwan; Belle, Mino D C; Piggins, Hugh D; Takumi, Toru; Forger, Daniel B

    2015-07-21

    The suprachiasmatic nuclei (SCN), the central circadian pacemakers in mammals, comprise a multiscale neuronal system that times daily events. We use recent advances in graphics processing unit computing to generate a multiscale model for the SCN that resolves cellular electrical activity down to the timescale of individual action potentials and the intracellular molecular events that generate circadian rhythms. We use the model to study the role of the neurotransmitter GABA in synchronizing circadian rhythms among individual SCN neurons, a topic of much debate in the circadian community. The model predicts that GABA signaling has two components: phasic (fast) and tonic (slow). Phasic GABA postsynaptic currents are released after action potentials, and can both increase or decrease firing rate, depending on their timing in the interspike interval, a modeling hypothesis we experimentally validate; this allows flexibility in the timing of circadian output signals. Phasic GABA, however, does not significantly affect molecular timekeeping. The tonic GABA signal is released when cells become very excited and depolarized; it changes the excitability of neurons in the network, can shift molecular rhythms, and affects SCN synchrony. We measure which neurons are excited or inhibited by GABA across the day and find GABA-excited neurons are synchronized by-and GABA-inhibited neurons repelled from-this tonic GABA signal, which modulates the synchrony in the SCN provided by other signaling molecules. Our mathematical model also provides an important tool for circadian research, and a model computational system for the many multiscale projects currently studying brain function. PMID:26130805

  9. Extent of colocalization of serotonin and GABA in neurons of the ventral medulla oblongata in rat.

    Science.gov (United States)

    Millhorn, D E; Hökfelt, T; Seroogy, K; Verhofstad, A A

    1988-09-27

    The colocalization of serotonin (5-hydroxytryptamine; 5-HT) and gamma-aminobutyric acid (GABA) in the ventral aspect of the rat medulla oblongata was studied using antibodies directed against 5-HT and GABA. Although 5-HT- and GABA-immunoreactive cell bodies were observed over the entire rostral-caudal extent of the ventral medulla, the colocalization of these two classical neurotransmitters in single cells was, for the most part, limited to a region that corresponds anatomically to nucleus raphe magnus/nucleus paragigantocellularis. Schematic drawings showing the distribution of 5-HT/GABA cell bodies in the ventral medulla are provided. PMID:3066433

  10. Opioid systems in the lateral hypothalamus regulate feeding behavior through orexin and GABA neurons.

    Science.gov (United States)

    Ardianto, C; Yonemochi, N; Yamamoto, S; Yang, L; Takenoya, F; Shioda, S; Nagase, H; Ikeda, H; Kamei, J

    2016-04-21

    The hypothalamus controls feeding behavior. Since central opioid systems may regulate feeding behavior, we examined the role of μ-, δ- and κ-opioid receptors in the lateral hypothalamus (LH), the hunger center, in feeding behavior of mice. Non-selective (naloxone; 3mg/kg, s.c.) and selective μ- (β-funaltrexamine, β-FNA; 10mg/kg, s.c.), δ- (naltrindole; 3mg/kg, s.c.) and κ- (norbinaltorphimine, norBNI; 20mg/kg, s.c.) opioid receptor antagonists significantly decreased food intake in food-deprived mice. The injection of naloxone (20μg/side) into the LH significantly decreased food intake whereas the injection of naloxone (20μg/side) outside of the LH did not affect food intake. The injection of β-FNA (2μg/side), naltrindole (1μg/side) or norBNI (2μg/side) into the LH significantly decreased food intake. Furthermore, all these antagonists significantly decreased the mRNA level of preproorexin, but not those of other hypothalamic neuropeptides. In addition, the injection of the GABAA receptor agonist muscimol (5μg/side) into the LH significantly decreased food intake, and this effect was abolished by the GABAA receptor antagonist bicuculline (50μg/side). Muscimol (1mg/kg, i.p.) decreased the mRNA level of preproorexin in the hypothalamus. Naloxone (3mg/kg, s.c.) significantly increased the GABA level in the LH and both bicuculline and the GABA release inhibitor 3-mercaptopropionic acid (3-MP, 5μg/side) attenuated the inhibitory effect of naloxone on feeding behavior. 3-MP also attenuated the effects of β-FNA and norBNI, but not that of naltrindole. These results show that opioid systems in the LH regulate feeding behavior through orexin neurons. Moreover, μ- and κ-, but not δ-, opioid receptor antagonists inhibit feeding behavior by activating GABA neurons in the LH. PMID:26855191

  11. Alterations at the cross-bridge level are associated with a paradoxical gain of muscle function in vivo in a mouse model of nemaline myopathy.

    Directory of Open Access Journals (Sweden)

    Charlotte Gineste

    Full Text Available Nemaline myopathy is the most common disease entity among non-dystrophic skeletal muscle congenital diseases. The first disease causing mutation (Met9Arg was identified in the gene encoding α-tropomyosin slow gene (TPM3. Considering the conflicting findings of the previous studies on the transgenic (Tg mice carrying the TPM3Met9Arg mutation, we investigated carefully the effect of the Met9Arg mutation in 8-9 month-old Tg(TPM3Met9Arg mice on muscle function using a multiscale methodological approach including skinned muscle fibers analysis and in vivo investigations by magnetic resonance imaging and 31-phosphorus magnetic resonance spectroscopy. While in vitro maximal force production was reduced in Tg(TPM3Met9Arg mice as compared to controls, in vivo measurements revealed an improved mechanical performance in the transgenic mice as compared to the former. The reduced in vitro muscle force might be related to alterations occurring at the cross-bridges level with muscle-specific underlying mechanisms. In vivo muscle improvement was not associated with any changes in either muscle volume or energy metabolism. Our findings indicate that TPM3(Met9Arg mutation leads to a mild muscle weakness in vitro related to an alteration at the cross-bridges level and a paradoxical gain of muscle function in vivo. These results clearly point out that in vitro alterations are muscle-dependent and do not necessarily translate into similar changes in vivo.

  12. Reductions in frontocortical cytokine levels are associated with long-lasting alterations in reward valuation after methamphetamine.

    Science.gov (United States)

    Stolyarova, Alexandra; Thompson, Andrew B; Barrientos, Ruth M; Izquierdo, Alicia

    2015-04-01

    Alterations in reward valuation are thought to have a central role at all stages of the addiction process. We previously reported work aversion in an effortful T-maze task following a binge exposure to methamphetamine, and no such changes in effort following escalating doses. Limitations of the T-maze task include its two available options, with an effort requirement, in the form of increasing barrier height, varying incrementally as a function of time, and reward magnitudes held constant. Reward preferences and choices, however, are likely affected by the number of options available and the manner in which alternatives are presented. In the present experiment, we investigated the long-lasting, off-drug effects of methamphetamine on reward choices in a novel effortful maze task with three possible courses of action, each associated with different effort requirements and reward magnitudes. Neuroinflammatory responses associated with drug exposure, proposed as one of the mechanisms contributing to suboptimal choices on effort-based tasks, were also examined. We investigated region-specific changes in pro- and anti-inflammatory markers in the mesocorticolimbic pathway after methamphetamine, and their relationship with animals' reward choices. We observed long-lasting, increased sensitivity to differences in reward magnitude in the methamphetamine group: animals were more likely to overcome greater effort costs to obtain larger rewards on our novel effortful maze task. These behavioral changes were strongly predicted by pronounced decreases in frontocortical cytokines, but not amygdalar or striatal markers. The present results provide the first evidence that neuroinflammatory processes are associated with alterations in reward valuation during protracted drug withdrawal. PMID:25409594

  13. Porin alterations present in non-carbapenemase-producing Enterobacteriaceae with high and intermediate levels of carbapenem resistance in Chile.

    Science.gov (United States)

    Wozniak, Aniela; Villagra, Nicolás A; Undabarrena, Agustina; Gallardo, Natalia; Keller, Nicole; Moraga, Marcela; Román, Juan C; Mora, Guido C; García, Patricia

    2012-09-01

    The main goal of this work was to identify the mechanisms responsible for carbapenem resistance in 61 Chilean clinical isolates of Enterobacteriaceae (Enterobacter spp., Serratia marcescens, Morganella morganii, Escherichia coli and Klebsiella pneumoniae) with reduced susceptibility to at least one carbapenem (ertapenem, imipenem or meropenem). All of the isolates were analysed for the presence of carbapenemases, extended spectrum β-lactamases (ESBLs), AmpC enzymes and outer-membrane proteins. None of the isolates exhibited carbapenemase activity nor did they have any of the carbapenemase genes that were screened for. Most of the 61 strains produced at least one ESBL and/or one AmpC enzyme and either lost their porins or had altered porins according to sequence analysis. The distribution of ESBLs and AmpC enzymes was different among the species studied. Resistance in K. pneumoniae and E. coli isolates was associated with ESBLs; in M. morganii isolates, resistance was attributed to overexpression of an AmpC enzyme; and in Enterobacter spp. isolates, resistance was associated with both types of enzymes. In K. pneumoniae isolates, porin integrity was more a determinant of carbapenem resistance than the presence of ESBLs, whereas in isolates of Enterobacter spp., M. morganii and S. marcescens, the presence of an overexpressed AmpC enzyme was associated with higher imipenem and meropenem MIC values. Therefore, carbapenem resistance in Chilean isolates is not due to true carbapenemases but rather to a combination of porin loss/alteration and β-lactamase activity. The fact that carbapenemases were not detected in this study is unique, given that many countries in the region have already reported the presence of these enzymes. PMID:22700549

  14. Liver histological alterations in patients with chronic hepatitis C and normal ALT levels in the city of Salvador, Northeast-Brazil

    Directory of Open Access Journals (Sweden)

    Nelma Pereira de Santana

    2005-04-01

    Full Text Available Patients with chronic hepatitis C can have variable clinical progression. Hepatic histological alterations appear to be milder in asymptomatic subjects who have persistently normal ALT levels. AIMS: To evaluate the severity of histological liver alterations in blood donors with normal and elevated ALT levels. METHODS: We evaluated volunteer blood donors from the main blood bank of the city of Salvador-Brazil. Those who were anti-HCV positive were invited to participate in the study. Serum ALT and AST levels were measured at two time points, two months apart. Donors were divided into two groups: group I, individuals with ALT > 1.5 times the upper limit of normal in at least one time point and group II, individuals with normal or near normal ALT, at both time points RESULTS: We evaluated 30,232 blood donors and 528 (1.7% of them were anti-HCV positive. Eighty-two attended our service and HCV infection was confirmed in 66 individuals. Male gender predominated in both groups; the mean age was 36 for group I, and 33 for group II. Tattoos and intravenous illicit drug use were frequently-encountered risk factors. Liver biopsy was done in 43 subjects. Among donors with elevated ALT, two (10% had minimum alterations, while in group II normal liver or minimum alterations were observed in six (26% subjects. Chronic hepatitis or cirrhosis was encountered in 35 (81% individuals: three (15% and five (21% subjects had chronic hepatitis without inflammatory activity, 10 (50% and 11 (48% had minimum to moderate activity and five (25% and one (4.3% had cirrhosis, in groups I and II, respectively (P was not significant. CONCLUSIONS: The prevalence of anti-HCV among this population of volunteer blood donors was 1.7%, and these subjects had few liver histological alterations or chronic hepatitis and cirrhosis. Liver injury severity was significant in patients with elevated ALT, however subjects with normal levels may also present chronic hepatitis and cirrhosis.

  15. Inhibition of protein kinase C decreases sensitivity of GABA receptor subtype to fipronil insecticide in insect neurosecretory cells.

    Science.gov (United States)

    Murillo, Laurence; Hamon, Alain; Es-Salah-Lamoureux, Zeineb; Itier, Valérie; Quinchard, Sophie; Lapied, Bruno

    2011-12-01

    Phosphorylation by serine/threonine kinases has been described as a new mechanism for regulating the effects of insecticides on insect neuronal receptors and channels. Although insect GABA receptors are commercially important targets for insecticides (e.g. fipronil), their modulation by kinases is poorly understood and the influence of phosphorylation on insecticide sensitivity is unknown. Using the whole-cell patch-clamp technique, we investigated the modulatory effect of PKC and CaMKinase II on GABA receptor subtypes (GABAR1 and GABAR2) in DUM neurons isolated from the terminal abdominal ganglion (TAG) of Periplaneta americana. Chloride currents through GABAR2 were selectively abolished by PMA and PDBu (the PKC activators) and potentiated by Gö6983, an inhibitor of PKC. Furthermore, using KN-62, a specific CaMKinase II inhibitor, we demonstrated that CaMKinase II activation was also involved in the regulation of GABAR2 function. In addition, using CdCl(2) (the calcium channel blocker) and LOE-908, a blocker of TRPγ, we revealed that calcium influx through TRPγ played an important role in kinase activations. Comparative studies performed with CACA, a selective agonist of GABAR1 in DUM neurons confirmed the involvement of these kinases in the specific regulation of GABAR2. Furthermore, our study reported that GABAR1 was less sensitive than GABAR2 to fipronil. This was demonstrated by the biphasic concentration-response curve and the current-voltage relationship established with both GABA and CACA. Finally, we demonstrated that GABAR2 was 10-fold less sensitive to fipronil following inhibition of PKC, whereas inhibition of CaMKinase II did not alter the effect of fipronil. PMID:21684305

  16. Acute Immobilization Stress Modulate GABA Release from Rat Olfactory Bulb: Involvement of Endocannabinoids—Cannabinoids and Acute Stress Modulate GABA Release

    OpenAIRE

    Alejandra Delgado; Erica H. Jaffé

    2011-01-01

    We studied the effects of cannabinoids and acute immobilization stress on the regulation of GABA release in the olfactory bulb. Glutamate-stimulated 3H-GABA release was measured in superfused slices. We report that cannabinoids as WIN55, 212-2, methanandamide, and 2-arachidonoylglycerol were able to inhibit glutamate- and KCl-stimulated 3H-GABA release. This effect was blocked by the CB1 antagonist AM281. On the other hand, acute stress was able per se to increase endocannabinoid activity. Th...

  17. Plasma PGE-2 levels and altered cytokine profiles in adherent peripheral blood mononuclear cells in non-small cell lung cancer (NSCLC

    Directory of Open Access Journals (Sweden)

    Hirschowitz Edward A

    2002-11-01

    Full Text Available Abstract Introduction PGE-2 is constitutively produced by many non-small cell lung cancers (NSCLC and its immunosuppressive effects have been linked to altered immune responses in lung cancer. We asked whether elevated levels of plasma PGE-2 correlated with monocyte IL10 production in the NSCLC environment. Looking for correlation in NSCLC patient blood we assayed plasma from NSCLC patients for PGE2 and IL10; we further evaluated production of IL10 by adherent mononuclear cells from a subset of these patients looking for an altered cytokine profile. Results Our initial in vitro experiments show that monocyte IL10 induction correlates with tumor cell PGE-2 production, confirming similar reports in the literature. Data show plasma PGE-2 levels in 38 NSCLC patients are elevated compared to normal controls. Plasma IL10 levels were not significantly elevated; however, adherent monocytes derived from NSCLC patient blood did produce significantly more IL10 in 24 hr primary culture than those from normal controls (p Conclusions Elevated plasma PGE-2 and monocyte IL10 production are associated with NSCLC. The biological significance to elevated PGE-2 levels in NSCLC are unclear. Further investigation of each as a nonspecific marker for NSCLC tumor is warranted.

  18. Depolarization by K*O+ and glutamate activates different neurotransmitter release mechanisms in gabaergic neurons: vesicular versus non-vesicular release of gaba

    DEFF Research Database (Denmark)

    Belhage, Bo; Hansen, G.H.; Schousboe, Arne

    1993-01-01

    Neurotransmitter release, gaba release, membrane transporter, vesicles, intracellular CA*OH, neuron cultures......Neurotransmitter release, gaba release, membrane transporter, vesicles, intracellular CA*OH, neuron cultures...

  19. Vitamin K_2 Alters Bone Metabolism Markers in Hemodialysis Patients with a Low Serum Parathyroid Hormone Level

    OpenAIRE

    Ochiai, Mariko; Nakashima, Ayumu; Takasugi, Norihisa; Kiribayashi, Kei; KAWAI, Toru; Usui, Koji; Shigemoto, Kenichiro; HAMAGUCHI, Naoki; Kohno, Nobuoki; Yorioka, Noriaki

    2011-01-01

    Background: A low level of intact parathyroid hormone (PTH) is an indicator of adynamic bone disease in hemodialysis patients, and is associated with a significant increase of all-cause mortality. Thus, effective treatment for adynamic bone disease is required. We previously investigated the effect of vitamin K2 on adynamic bone disease. In this study, we assessed the efficacy of oral vitamin K2 in a controlled trial. Methods: Forty hemodialysis patients with low intact PTH levels (

  20. Evaluation of the vertical alterations of the upper second molars after the alignment and leveling phase using the MBT technique

    OpenAIRE

    Alael Barreiro Fernandes de Paiva Lino; Julio Wilson Vigorito

    2013-01-01

    OBJECTIVE: This study aimed at comparing the distocervical angulations of upper second molars crowns of groups with normal occlusion and with Angle Class I and II malocclusions. Additionally, it aimed to analyze the changes occurring after alignment and leveling performed with MBT technique. METHODS: The sample of normal occlusions comprised 32 lateral teleradiographs, while the sample of malocclusions comprised 38 initial and post-leveling lateral teleradiographs. RESULTS: The results did no...

  1. Microbial communities on seafloor basalts at Dorado Outcrop reflect level of alteration and highlight global lithic clades

    Directory of Open Access Journals (Sweden)

    Michael D Lee

    2015-12-01

    Full Text Available Areas of exposed basalt along mid-ocean ridges and at seafloor outcrops serve as conduits of fluid flux into and out of a subsurface ocean, and microbe-mineral interactions can influence alteration reactions at the rock-water interface. Located on the eastern flank of the East Pacific Rise, Dorado Outcrop is a site of low-temperature (<20°C hydrothermal venting and represents a new end-member in the current survey of seafloor basalt biomes. Consistent with prior studies, a survey of 16S rRNA gene sequence diversity using universal primers targeting the V4 hypervariable region revealed much greater richness and diversity on seafloor rocks than in surrounding seawater. Overall, Gamma-, Alpha-, and Deltaproteobacteria, and Thaumarchaeota dominated the sequenced communities, together making up over half of the observed diversity, though bacterial sequences were more abundant than archaeal in all samples. The most abundant bacterial reads were closely related to the obligate chemolithoautotrophic, sulfur-oxidizing Thioprofundum lithotrophicum, suggesting carbon and sulfur cycling as dominant metabolic pathways in this system. Representatives of Thaumarchaeota were detected in relatively high abundance on the basalts in comparison to bottom water, possibly indicating ammonia oxidation. In comparison to other sequence datasets from globally distributed seafloor basalts, this study reveals many overlapping and cosmopolitan phylogenetic groups and also suggests that substrate age correlates with community structure.

  2. Glutamate and GABA in Vestibulo-Sympathetic Pathway Neurons.

    Science.gov (United States)

    Holstein, Gay R; Friedrich, Victor L; Martinelli, Giorgio P

    2016-01-01

    The vestibulo-sympathetic reflex (VSR) actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The VSR pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively). The present study assessed glutamate- and GABA-related immunofluorescence associated with central vestibular neurons of the VSR pathway in rats. Retrograde FluoroGold tract tracing was used to label vestibular neurons with projections to RVLM or CVLM, and sinusoidal galvanic vestibular stimulation (GVS) was employed to activate these pathways. Central vestibular neurons of the VSR were identified by co-localization of FluoroGold and cFos protein, which accumulates in some vestibular neurons following galvanic stimulation. Triple-label immunofluorescence was used to co-localize glutamate- or GABA- labeling in the identified VSR pathway neurons. Most activated projection neurons displayed intense glutamate immunofluorescence, suggestive of glutamatergic neurotransmission. To support this, anterograde tracer was injected into the caudal vestibular nuclei. Vestibular axons and terminals in RVLM and CVLM co-localized the anterograde tracer and vesicular glutamate transporter-2 signals. Other retrogradely-labeled cFos-positive neurons displayed intense GABA immunofluorescence. VSR pathway neurons of both phenotypes were present in the caudal medial and spinal vestibular nuclei, and projected to both RVLM and CVLM. As a group, however, triple-labeled vestibular cells with intense glutamate immunofluorescence were located more rostrally in the vestibular nuclei than the GABAergic neurons. Only the GABAergic VSR pathway neurons showed a target preference, projecting predominantly to CVLM. These data provide the first

  3. Glutamate and GABA in vestibulo-sympathetic pathway neurons

    Directory of Open Access Journals (Sweden)

    Gay R Holstein

    2016-02-01

    Full Text Available The vestibulo-sympathetic reflex actively modulates blood pressure during changes in posture. This reflex allows humans to stand up and quadrupeds to rear or climb without a precipitous decline in cerebral perfusion. The vestibulo-sympathetic reflex pathway conveys signals from the vestibular end organs to the caudal vestibular nuclei. These cells, in turn, project to pre-sympathetic neurons in the rostral and caudal ventrolateral medulla (RVLM and CVLM, respectively. The present study assessed glutamate- and GABA-related immunofluorescence associated with central vestibular neurons of the vestibulo-sympathetic reflex pathway in rats. Retrograde FluoroGold tract tracing was used to label vestibular neurons with projections to RVLM or CVLM, and sinusoidal galvanic vestibular stimulation was employed to activate these pathways. Central vestibular neurons of the vestibulo-sympathetic reflex were identified by co-localization of FluoroGold and cFos protein, which accumulates in some vestibular neurons following galvanic stimulation. Triple-label immunofluorescence was used to co-localize glutamate- or GABA- labeling in the identified vestibulo-sympathetic reflex pathway neurons. Most activated projection neurons displayed intense glutamate immunofluorescence, suggestive of glutamatergic neurotransmission. To support this, anterograde tracer was injected into the caudal vestibular nuclei. Vestibular axons and terminals in RVLM and CVLM co-localized the anterograde tracer and vesicular glutamate transporter-2 signals. Other retrogradely-labeled cFos-positive neurons displayed intense GABA immunofluorescence. Vestibulo-sympathetic reflex pathway neurons of both phenotypes were present in the caudal medial and spinal vestibular nuclei, and projected to both RVLM and CVLM. As a group, however, triple-labeled vestibular cells with intense glutamate immunofluorescence were located more rostrally in the vestibular nuclei than the GABAergic neurons. Only the

  4. Isolation, characterization, and tissue-specific expression of GABA A receptor α1 subunit gene of Carassius auratus gibelio after avermectin treatment.

    Science.gov (United States)

    Zhao, Yini; Sun, Qi; Hu, Kun; Ruan, Jiming; Yang, Xianle

    2016-02-01

    Carassius auratus gibelio has been widely cultivated in fish farms in China, with avermectin (AVM) being used to prevent parasite infection. Recently, AVM was found to pass through the Carassius auratus gibelio blood-brain barrier (BBB). Although AVM acts mainly through a GABA receptor and specifically the α1 subunit gene, the most common isoform of the GABA A receptor, which is widely expressed in brain neurons and has been studied in other fish, Carassius auratus gibelio GABA A receptor α1 subunit gene cloning, and whether AVM passes through the BBB to induce Carassius auratus gibelio GABA A receptor α1 subunit gene expression have not been studied. The aim of this study was to clone, sequence, and phylogenetically analyze the GABA A receptor α1 subunit gene and to investigate the correlation of its expression with neurotoxicity in brain, liver, and kidney after AVM treatment by quantitative real-time reverse transcription polymerase chain reaction. The α1 subunit gene was 1550 bp in length with an open reading frame of 1380 bp encoding a predicted protein with 459 amino acid residues. The gene contained 128 bp of 5' terminal untranslated region (URT) and 72 bp of 3' terminal UTR. The α1 subunit structural features conformed to the Cys-loop ligand-gated ion channels family, which includes a signal peptide, an extracellular domain at the N-terminal, and four transmembrane domains. The established phylogenetic tree indicated that the α1 subunits of Carassius auratus gibelio and Danio rerio were the most closely related to each other. The α1 subunit was found to be highly expressed in brain and ovary, and the α1 mRNA transcription level increased significantly in brain. Moreover, the higher the concentration of AVM was, the higher the GABA A receptor expression was, indicating that AVM can induce significant neurotoxicity to Carassius auratus gibelio. Therefore, the α1 subunit mRNA expression was positively correlated with the neurotoxicity of AVM in

  5. Bisphenol A alters transcript levels of biomarker genes for Major Depressive Disorder in vascular endothelial cells and colon cancer cells.

    Science.gov (United States)

    Ribeiro-Varandas, Edna; Pereira, H Sofia; Viegas, Wanda; Delgado, Margarida

    2016-06-01

    Bisphenol A (BPA) is capable of mimicking endogenous hormones with potential consequences for human health and BPA exposure has been associated with several human diseases including neuropsychiatric disorders. Here, quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) results show that BPA at low concentrations (10 ng/mL and 1 μg/mL) induces differential transcript levels of four biomarker genes for Major Depressive Disorder (MDD) in HT29 human colon adenocarcinona cell line and Human Umbilical Vein Endothelial Cells (HUVEC). These results substantiate increasing concerns of BPA exposure in levels currently detected in humans. PMID:27010169

  6. Projected near-future CO2 levels increase activity and alter defensive behaviours in the tropical squid Idiosepius pygmaeus

    OpenAIRE

    Blake L. Spady; Sue-Ann Watson; Chase, Tory J.; Munday, Philip L.

    2014-01-01

    Carbon dioxide (CO2) levels projected to occur in the oceans by the end of this century cause a range of behavioural effects in fish, but whether other highly active marine organisms, such as cephalopods, are similarly affected is unknown. We tested the effects of projected future CO2 levels (626 and 956 µatm) on the behaviour of male two-toned pygmy squid, Idiosepius pygmaeus. Exposure to elevated CO2 increased the number of active individuals by 19–25% and increased movement (number of line...

  7. Projected near-future CO2 levels increase activity and alter defensive behaviours in the tropical squid Idiosepius pygmaeus

    OpenAIRE

    Blake L. Spady; Watson, Sue-Ann; Chase, Tory J.; Munday, Philip L.

    2014-01-01

    ABSTRACT Carbon dioxide (CO2) levels projected to occur in the oceans by the end of this century cause a range of behavioural effects in fish, but whether other highly active marine organisms, such as cephalopods, are similarly affected is unknown. We tested the effects of projected future CO2 levels (626 and 956 µatm) on the behaviour of male two-toned pygmy squid, Idiosepius pygmaeus. Exposure to elevated CO2 increased the number of active individuals by 19–25% and increased movement (numbe...

  8. [Effect of the GABA derivative phenibut on learning].

    Science.gov (United States)

    Shul'gina, G I; Ziablitseva, E A

    2005-01-01

    The learning effect of phenibut, a beta-phenyl derivative of the inhibitory neuromediator GABA, used in a subcutaneous dose of 40 mg/kg 2 hours before each experiment, was studied in rabbits. The injection of phenibut was shown to enhance not only the inhibitory, but also excitatory components of cerebral cortical neuronal responses to all applied stimuli. The findings support the concept that the GABAergic neuromediator system is involved in the elaboration of internal inhibition and explain the sense of intracerebral processes that ensure both the sedative properties of phenibut and its ability to improve patients' systemic tone and health status when brain dysfunctions are treated. PMID:15776965

  9. Patients treated for male pattern hair with finasteride show, after discontinuation of the drug, altered levels of neuroactive steroids in cerebrospinal fluid and plasma.

    Science.gov (United States)

    Caruso, Donatella; Abbiati, Federico; Giatti, Silvia; Romano, Simone; Fusco, Letizia; Cavaletti, Guido; Melcangi, Roberto Cosimo

    2015-02-01

    Observations performed in a subset of patients treated for male pattern hair loss indicate that persistent sexual side effects as well as anxious/depressive symptomatology have been reported even after discontinuation of finasteride treatment. Due to the capability of finasteride to block the metabolism of progesterone (PROG) and/or testosterone (T) we have evaluated, by liquid chromatography-tandem mass spectrometry, the levels of several neuroactive steroids in paired plasma and cerebrospinal fluid (CSF) samples obtained from post-finasteride patients and in healthy controls. At the examination, post-finasteride patients reported muscular stiffness, cramps, tremors and chronic fatigue in the absence of clinical evidence of any muscular disorder or strength reduction. Although severity of the anxious/depressive symptoms was quite variable in their frequency, overall all the subjects had a fairly complex and constant neuropsychiatric pattern. Assessment of neuroactive steroid levels in CSF showed a decrease of PROG and its metabolites, dihydroprogesterone (DHP) and tetrahydroprogesterone (THP), associated with an increase of its precursor pregnenolone (PREG). Altered levels were also observed for T and its metabolites. Thus, a significant decrease of dihydrotestosterone (DHT) associated with an increase of T as well as of 3α-diol was detected. Changes in neuroactive steroid levels also occurred in plasma. An increase of PREG, T, 3α-diol, 3β-diol and 17β-estradiol was associated with decreased levels of DHP and THP. The present observations show that altered levels of neuroactive steroids, associated with depression symptoms, are present in androgenic alopecia patients even after discontinuation of the finasteride treatment. This article is part of a Special Issue entitled 'Sex steroids and brain disorders'. PMID:24717976

  10. GABA Acts as a Ligand Chaperone in the Early Secretory Pathway to Promote Cell Surface Expression of GABAA Receptors

    OpenAIRE

    Eshaq, Randa S.; Stahl, Letha D.; Stone, Randolph; Smith, Sheryl S.; Robinson, Lucy C.; Leidenheimer, Nancy J.

    2010-01-01

    GABA (γ-aminobutyric acid) is the primary inhibitory neurotransmitter in brain. The fast inhibitory effect of GABA is mediated through the GABAA receptor, a postsynaptic ligand-gated chloride channel. We propose that GABA can act as a ligand chaperone in the early secretory pathway to facilitate GABAA receptor cell surface expression. Forty-two hrs of GABA treatment increased the surface expression of recombinant receptors expressed in HEK 293 cells, an effect accompanied by an increase in GA...

  11. Perioperative prostate specific antigen levels among coronary artery bypass grafting patients: Does extracorporeal circulation and body temperature induce prostate specific antigen levels alterations?

    Science.gov (United States)

    Patris, Emmanuel; Giakoumidakis, Konstantinos; Patris, Vasileios; Kuduvalli, Manoj; Argiriou, Mihalis; Charitos, Christos; Kalaitzis, Christos; Touloupidis, Stavros

    2015-01-01

    Purpose: The purpose of this study is to compare the perioperative total prostate specific antigen (tPSA) levels among coronary artery bypass grafting (CABG) patients with and without extracorporeal circulation (ECC), to investigate the changes overtime of tPSA in each group separately and to determine the effect of body core temperature on tPSA levels. Materials and Methods: A prospective study was conducted. Our sample was allocated to: (a) Seven patients who underwent off pump CABG (Group I) and (b) 16 CABG patients with ECC (Group II). The levels of tPSA were measured preoperatively (baseline), intra-operatively and at the 4th postoperative day. We compared the two groups on their tPSA levels and we investigated the changes of tPSA overtime in each group separately. Results: Intra-operative serum samples were obtained in significantly lower body temperature in patients of Group II than in those of Group I (31°C vs. 36.9°C, P < 0.001). In each group separately, postoperative tPSA levels were increased significantly compared to the baseline values (2.55 ng/ml vs. 0.39 ng/ml for Group I, P = 0.005 and 4.36 ng/ml vs. 0.77 for Group II, P < 0.001). CABG patients with ECC had significantly lower intra-operative tPSA levels than the baseline values (0.67 ng/ml vs. 0.77 ng/ml, P = 0.008). We did not observe significant differences of tPSA levels between the two groups. Conclusions: CABG surgery affects similarly the perioperative tPSA independently the involvement of ECC. Although all patients had significantly higher early postoperative tPSA levels, only those who underwent CABG with ECC had exceeded normal values and significantly decreased intra-operative tPSA. Hypothermia seems to be the causal factor of tPSA reduction. PMID:25657546

  12. CHARACTERIZATION OF EXTRACELLULAR GABA IN THE SUBSTANTIA-NIGRA-RETICULATA BY MEANS OF BRAIN MICRODIALYSIS

    NARCIS (Netherlands)

    TIMMERMAN, W; ZWAVELING, J; WESTERINK, BHC

    1992-01-01

    Brain microdialysis was used to characterize extracellular gamma-aminobutyric acid (GABA) in the substantia nigra reticulata (SNR) of freely moving rats. The extracellular GABA in the SNR was characterized using acutely implanted probes (4-8 h after surgery; day 1) and chronically implanted probes (

  13. Radioprotective effect of GABA-tropic substances, γ-hydroxybutyrate and pyracetame

    International Nuclear Information System (INIS)

    From experiments in mice, it is shown that with a radiation dose of 8 Gy (LD96) the radioprotective effect was exerted by gamma-aminobutyric acid (GABA), substances that increase its concentration in tissues (progabide and valproate), and synthetic agonists of both receptor types, particularly baclofen, a GABA-receptor agonist. The radioprotective effect is also exerted by gamma-hydroxybutyrate, not pyracetame

  14. Neurotransmitters as food supplements: the effects of GABA on brain and behavior

    NARCIS (Netherlands)

    E. Boonstra; R. Kleijn; L.S. Colzato; A. Alkemade; B.U. Forstmann; S. Nieuwenhuis

    2015-01-01

    Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the human cortex. The food supplement version of GABA is widely available online. Although many consumers claim that they experience benefits from the use of these products, it is unclear whether these supplements confer benef

  15. Hco-LGC-38 is novel nematode cys-loop GABA receptor subunit.

    Science.gov (United States)

    Siddiqui, Salma Z; Brown, David D R; Accardi, Michael V; Forrester, Sean G

    2012-10-01

    We have identified and characterized a novel cys-loop GABA receptor subunit (Hco-LGC-38) from the parasitic nematode Haemonchus contortus. This subunit is present in parasitic and free-living nematodes and shares similarity to both the UNC-49 group of GABA receptor subunits from nematodes and the resistant to dieldrin (RDL) receptors of insects. Expression of the Hco-lgc-38 gene in Xenopus oocytes and subsequent electrophysiological analysis has revealed that the gene encodes a homomeric channel sensitive to GABA (EC(50) 19 μM) and the GABA analogue muscimol. The sensitivity of the Hco-LGC-38 channel to GABA is similar to reported values for the Drosophila RDL receptor whereas its lower sensitivity to muscimol is similar to nematode GABA receptors. Hco-LGC-38 is also highly sensitive to the channel blocker picrotoxin and moderately sensitive to fipronil and dieldrin. Homology modeling of Hco-LGC-38 and subsequent docking of GABA and muscimol into the binding site has uncovered several types of potential interactions with binding-site residues and overall appears to share similarity with models of other invertebrate GABA receptors. PMID:22940478

  16. Temperature dependence and GABA modulation of (TH)triazolam binding in the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Earle, M.E.; Concas, A.; Wamsley, J.K.; Yamamura, H.I.

    1987-07-27

    The hypnotic triazolam (TZ), a triazolobenzodiazepine displays a short physiological half life and has been used for the treatment of insomnia related to anxiety states. The authors major objectives were the direct measurement of the temperature dependence and the gamma-aminobutyric acid (GABA) effect of (TH)TZ binding in the rat brain. Saturation studies showed a shift to lower affinity with increasing temperatures (K/sub d/ = 0.27 +/- 08 nM at 0C; K/sub d/ = 1.96 +/- 0.85 nM at 37C) while the B/sub max/ values remained unchanged (1220 +/- 176 fmoles/mg protein at 0C and 1160 +/- 383 fmoles/mg protein at 37C). Saturation studies of (TH)TZ binding in the presence or absence of GABA (100 M) showed a GABA-shift. At 0C the K/sub d/ values were (K/sub d/ = 0.24 +/- 0.03 nM/-GABA; K/sub d/ = 0.16 +/- 0.04/+GABA) and at 37C the K/sub d/ values were (K/sub d/ = 1.84 +/- 0.44 nM/-GABA; K/sub d/ = 0.95 +/- 0.29 nM/+GABA). In contrast to reported literature, the authors findings show that TZ interacts with benzodiazepine receptors with a temperature dependence and GABA-shift consistent with predicted behavior for benzodiazepine agonists. 20 references, 3 tables.

  17. Temperature dependence and GABA modulation of [3H]triazolam binding in the rat brain

    International Nuclear Information System (INIS)

    The hypnotic triazolam (TZ), a triazolobenzodiazepine displays a short physiological half life and has been used for the treatment of insomnia related to anxiety states. The authors major objectives were the direct measurement of the temperature dependence and the gamma-aminobutyric acid (GABA) effect of [3H]TZ binding in the rat brain. Saturation studies showed a shift to lower affinity with increasing temperatures (K/sub d/ = 0.27 +/- 08 nM at 00C; K/sub d/ = 1.96 +/- 0.85 nM at 370C) while the B/sub max/ values remained unchanged (1220 +/- 176 fmoles/mg protein at 00C and 1160 +/- 383 fmoles/mg protein at 370C). Saturation studies of [3H]TZ binding in the presence or absence of GABA (100μM) showed a GABA-shift. At 00C the K/sub d/ values were (K/sub d/ = 0.24 +/- 0.03 nM/-GABA; K/sub d/ = 0.16 +/- 0.04/+GABA) and at 370C the K/sub d/ values were (K/sub d/ = 1.84 +/- 0.44 nM/-GABA; K/sub d/ = 0.95 +/- 0.29 nM/+GABA). In contrast to reported literature, the authors findings show that TZ interacts with benzodiazepine receptors with a temperature dependence and GABA-shift consistent with predicted behavior for benzodiazepine agonists. 20 references, 3 tables

  18. Effect of GABA, a Bacterial Metabolite, on Pseudomonas fluorescens Surface Properties and Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Marc G. J. Feuilloley

    2013-06-01

    Full Text Available Different bacterial species and, particularly Pseudomonas fluorescens, can produce gamma-aminobutyric acid (GABA and express GABA-binding proteins. In this study, we investigated the effect of GABA on the virulence and biofilm formation activity of different strains of P. fluorescens. Exposure of a psychotropic strain of P. fluorescens (MF37 to GABA (10−5 M increased its necrotic-like activity on eukaryotic (glial cells, but reduced its apoptotic effect. Conversely, muscimol and bicuculline, the selective agonist and antagonist of eukaryote GABAA receptors, respectively, were ineffective. P. fluorescens MF37 did not produce biosurfactants, and its caseinase, esterase, amylase, hemolytic activity or pyoverdine productions were unchanged. In contrast, the effect of GABA was associated to rearrangements of the lipopolysaccharide (LPS structure, particularly in the lipid A region. The surface hydrophobicity of MF37 was marginally modified, and GABA reduced its biofilm formation activity on PVC, but not on glass, although the initial adhesion was increased. Five other P. fluorescens strains were studied, and only one, MFP05, a strain isolated from human skin, showed structural differences of biofilm maturation after exposure to GABA. These results reveal that GABA can regulate the LPS structure and cytotoxicity of P. fluorescens, but that this property is specific to some strains.

  19. [Classification of mental phenomena as the highest integration level of man's relationship to the environment (with remarks on the phenomenon of altered states of consciousness)].

    Science.gov (United States)

    Pickenhain, L

    1975-11-01

    In recent years mystical ideas have been spreading concerning "altered states of consciousness" as "new dimensions of experience and transpersonal communication". An analysis is given of the class-conditioned character of these concepts deriving from the insecure social conditions existing under moribund imperialism. This is contrasted with the dialectical materialist concept of psychic phenomena as the highest integration level of man's relationship to the environment. Psychic phenomena are interpreted not as epiphenomena but as an expression of the new quality attained in the evolution of man as a social being in the central control of all functions of man's organism. PMID:1215439

  20. Regulation by divalent cations of 3H-baclofen binding to GABA/sub B/ sites in rat cerebellar membranes

    International Nuclear Information System (INIS)

    When investigating the effects of divalent cations (Mg2+, Ca2+, Sr2+, Ba2+, Mn2+ and Ni2+) on 3H-baclofen binding to rat cerebellar synaptic membranes, we found that the specific binding of 3H-baclofen was not only dependent on divalent cations, but was increased dose-dependently in the presence of these cations. The effects were in the following order of potency: Mn2+ approx. = Ni2+ > Mg2+ > Ca2+ > Sr2+ > Ba2+. Scatchard analysis of the binding data revealed a single component of the binding sites in the presence of 2.5 mM MgCl2, 2.5 mM CaCl2 or 0.3 mM MnCl2 whereas two components appeared in the presence of 2.5 mM MnCl2 or 1 mM NiCl2. In the former, divalent cations altered the apparent affinity (K/sub d/) without affecting density of the binding sites (B/sub max/). In the latter, the high-affinity sites showed a higher affinity and lower density of the binding sites than did the single component of the former. As the maximal effects of four cations (Mg2+, Ca2+, Mn2+, and Ni2+) were not additive, there are probably common sites of action of these divalent cations. Among the ligands for GABA/sub B/ sites, the affinity for (-), (+) and (+/-)baclofen, GABA and β-phenyl GABA increased 2 - 6 fold in the presence of 2.5 mM MnCl2, in comparison with that in HEPES-buffered Krebs solution (containing 2.5 mM CaCl2 and 1.2 mM MgSO4), whereas that for muscimol was decreased to one-fifth. Thus, the affinity of GABA/sub B/ sites for its ligands is probably regulated by divalent cations, through common sites of action

  1. Potential Association of Lead Exposure During Early Development of Mice With Alteration of Hippocampus Nitric Oxide Levels and Learning Memory

    Institute of Scientific and Technical Information of China (English)

    LI SUN; ZHENG-YAN ZHAO; JIAN HU; XIE-LAI ZHOU

    2005-01-01

    Objective Chronic lead (Pb) exposure during development is known to produce learning deficits. Nitric oxide participates in the synaptic mechanisms involved in certain forms of learning and memory. This study was designed to clarify whether Pb-induced impairment in learning and memory was associated with the changes of nitric oxide levels in mice brains.Methods Sixty Balb/c mice aged 10 days were chosen. A model of lead exposure was established by drinking 0.025%, 0.05%,0.075% lead acetate, respectively for 8 weeks. The controls were orally given distilled water. The ability to learn and memorize was examined by open field test, T-water maze test. In parallel with the behavioral data, NO level of hippocampus tissue was detected by biochemical assay. Results Compared with control groups, (1) the weight of 0.075% group was significantly reduced (P<0.05); (2) The number of times in mice attaining the required standards in T-water maze test was lower in 0.075%group (P<0.01). No significant difference was found between experimental and control groups in open field test (P>0.05); (3)NO level of mouse hippocampus tissue was decreased in 0.075% group (P<0.01). Conclusions The findings suggest that decreased hippocampus NO level may contribute to the Pb-induced deficits in learning and memory processes.

  2. Altered Circulating Levels of Serotonin and Immunological Changes in Laying Hens Divergently Selected for Feather Pecking Behavior

    DEFF Research Database (Denmark)

    Buitenhuis, Albert Johannes; Kjaer, Jørgen B.; Labouriau, Rodrigo;

    2006-01-01

    The aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (FP) behavior [high FP (HP) line and low FP (LP) line] for 5 generations. The hens from the...

  3. Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

    DEFF Research Database (Denmark)

    Bayley, M; Baatrup, E; Heimbach, U;

    1995-01-01

    effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

  4. Sex Hormones in Allergic Conjunctivitis: Altered Levels of Circulating Androgens and Estrogens in Children and Adolescents with Vernal Keratoconjunctivitis

    Directory of Open Access Journals (Sweden)

    Marta Sacchetti

    2015-01-01

    Full Text Available Purpose. Vernal keratoconjunctivitis (VKC is a chronic allergic disease mainly affecting boys in prepubertal age and usually recovering after puberty. To evaluate a possible role of sex hormones in VKC, serum levels of sex hormones in children and adolescents with VKC were assessed. Methods. 12 prepubertal and 7 early pubertal boys with active VKC and 6 male patients with VKC in remission phase at late pubertal age and 48 healthy age and sex-matched subjects were included. Serum concentration of estrone, 17 beta-estradiol, dehydroepiandrosterone-sulfate, total testosterone and free testosterone, dihydrotestosterone (DHT, cortisol, delta-4-androstenedione, follicle-stimulating hormone, luteinizing hormone, and sex-hormones binding globuline (SHBG were evaluated. Results. Serum levels of Estrone were significantly increased in all groups of patients with VKC when compared to healthy controls (P<0.001. Prepubertal and early pubertal VKC showed a significant decrease in DHT (P=0.007 and P=0.028, resp. and SHBG (P=0.01 and P=0.002, resp. when compared to controls and serum levels of SHBG were increased in late pubertal VKC in remission phase (P=0.007. Conclusions and Relevance. VKC patients have different circulating sex hormone levels in different phases of the disease and when compared to nonallergic subjects. These findings suggest a role played by sex hormones in the pathogenesis and/or activity of VKC.

  5. A possible role of the non-GAT1 GABA transporters in transfer of GABA from GABAergic to glutamatergic neurons in mouse cerebellar neuronal cultures

    DEFF Research Database (Denmark)

    Suñol, C; Babot, Z; Cristòfol, R;

    2010-01-01

    Cultures of dissociated cerebellum from 7-day-old mice were used to investigate the mechanism involved in synthesis and cellular redistribution of GABA in these cultures consisting primarily of glutamatergic granule neurons and a smaller population of GABAergic Golgi and stellate neurons. The...... distribution of GAD, GABA and the vesicular glutamate transporter VGlut-1 was assessed using specific antibodies combined with immunofluorescence microscopy. Additionally, tiagabine, SKF 89976-A, betaine, beta-alanine, nipecotic acid and guvacine were used to inhibit the GAT1, betaine/GABA (BGT1), GAT2 and GAT...... neurons constituting the majority of the cells. GABA uptake exhibited the kinetics of high affinity transport and could be partly (20%) inhibited by betaine (IC(50) 142 microM), beta-alanine (30%) and almost fully (90%) inhibited by SKF 89976-A (IC(50) 0.8 microM) or nipecotic acid and guvacine at 1 m...

  6. GABA mediated response of aqueous, ethanol and ethyl acetate extracts of Dicranopteris linearis leaf in Swiss Albino mice

    Directory of Open Access Journals (Sweden)

    Billah Mohammad Mustakim

    2016-01-01

    Full Text Available Introduction: The objective of the study was to assess the potential of the leaf of Dicranopteris linearis in altering the CNS functions with three different extracts; aqueous, ethanol and ethyl acetate.Methods: To evaluate and compare the activities Morris maze, elevated plus maze (EPM,open field, hole cross and head dip tests were performed and many behavioral parameters wereobserved. The forced swim in Morris water maze analyzed the depression of rodents in termsof inability to self-rescue. Alongside, hole cross and open field tests assessed the inhibition oflocomotor activities. Moreover, EPM test screened the anxiolytic potential while the head dippinghole board test supported the previous experiments by evaluating both sedative, depressive andanxiolytic potentials of the extracts.Results: The results showed that the ethanol extract significantly suppressed CNS activity byreducing number of locomotor activities and increasing the stability phase (in EPM and Morrismaze supporting mild sedation, depression and anxiolysis. Furthermore, the ethyl acetate extractalso possessed moderate to high potential in reducing locomotor activities depending on gradientdoses. Results were compared with control group and found statistically significant.Conclusion: As this plant mimic the activity of a gamma-aminobutyric acid (GABA agonist, itcan be concluded that the plant may have GABA mediated involvement in central nervous system.However, the responsible compounds for these activities are yet to be investigated and this maypotentiate a new source of drug development.

  7. Alterations in vitamin D status and anti-microbial peptide levels in patients in the intensive care unit with sepsis

    Directory of Open Access Journals (Sweden)

    Ziegler Thomas R

    2009-04-01

    Full Text Available Abstract Background Vitamin D insufficiency is common in hospitalized patients. Recent evidence suggests that vitamin D may enhance the innate immune response by induction of cathelicidin (LL-37, an endogenous antimicrobial peptide produced by macrophages and neutrophils. Thus, the relationship between vitamin D status and LL-37 production may be of importance for host immunity, but little data is available on this subject, especially in the setting of human sepsis syndrome and other critical illness. Methods Plasma concentrations of 25-hydroxyvitamin D (25(OHD, vitamin D binding protein (DBP and LL-37 in critically ill adult subjects admitted to intensive care units (ICUs with sepsis and without sepsis were compared to healthy controls. Results Critically ill subjects had significantly lower plasma 25(OHD concentrations compared to healthy controls. Mean plasma LL-37 levels were significantly lower in critically ill subjects compared to healthy controls. Vitamin D binding protein levels in plasma were significantly lower in critically ill subjects with sepsis compared to critically ill subjects without sepsis. There was a significant positive association between circulating 25(OHD and LL-37 levels. Conclusion This study demonstrates an association between critical illness and lower 25(OHD and DBP levels in critically ill patients as compared to healthy controls. It also establishes a positive association between vitamin D status and plasma LL-37, which suggests that systemic LL-37 levels may be regulated by vitamin D status. Optimal vitamin D status may be important for innate immunity especially in the setting of sepsis. Further invention studies to examine this association are warranted.

  8. THE SIGNIFICANCE OF EXTRACELLULAR GABA IN THE SUBSTANTIA-NIGRA OF THE RAT DURING SEIZURES AND ANTICONVULSANT TREATMENTS

    NARCIS (Netherlands)

    SAYIN, U; TIMMERMAN, W; WESTERINK, BHC

    1995-01-01

    The effects of the anti-epileptic drugs valproic acid and gamma-vinyl-GABA (vigabatrin) on the extracellular content of GABA was determined by microdialysis. Probes were implanted in the substantia nigra reticulata (SNR) of rats. It was found that gamma-vinyl-GABA (1000 mg/kg) induced a 4-6-fold inc

  9. Regulation of 3H-dopamine release by presynaptic GABA and glutamate heteroreceptors in rat brain nucleus accumbens synaptosomes

    International Nuclear Information System (INIS)

    The aim of this investigation was a neurochemical study of the effect of agonists of different types of GABA receptors - muscimol (type A receptor), baclofen (type B receptor), delta-aminolevulinic acid (DALA; GABA autoreceptor), and also of GABA itself - on tritium-labelled dopamine release, stimulated by potassium cations, from synaptosomes of the nuclei accumbenes of the rat brain

  10. Regulation of /sup 3/H-dopamine release by presynaptic GABA and glutamate heteroreceptors in rat brain nucleus accumbens synaptosomes

    Energy Technology Data Exchange (ETDEWEB)

    Kovalev, G.I.; Hetey, L.

    1987-06-01

    The aim of this investigation was a neurochemical study of the effect of agonists of different types of GABA receptors - muscimol (type A receptor), baclofen (type B receptor), delta-aminolevulinic acid (DALA; GABA autoreceptor), and also of GABA itself - on tritium-labelled dopamine release, stimulated by potassium cations, from synaptosomes of the nuclei accumbenes of the rat brain.

  11. Knockout of GAD65 has major impact on synaptic GABA synthesized from astrocyte-derived glutamine

    DEFF Research Database (Denmark)

    Walls, Anne Byriel; Eyjolfsson, Elvar M.; Smeland, Olav B.;

    2011-01-01

    65 for maintenance of the highly compartmentalized intracellular and intercellular GABA homeostasis, GAD65 knockout and corresponding wild-type mice were injected with [1-(13)C]glucose and the astrocyte-specific substrate [1,2-(13)C]acetate. Synthesis of GABA from glutamine in the GABAergic synapses...... cortex and hippocampus. The GABA content in both brain regions was reduced by ∼20%. Moreover, it was revealed that GAD65 is crucial for maintenance of biosynthesis of synaptic GABA particularly by direct synthesis from astrocytic glutamine via glutamate. The GAD67 was found to be important for synthesis...... of GABA from glutamine both via direct synthesis and via a pathway involving mitochondrial metabolism. Furthermore, a severe neuronal hypometabolism, involving glycolysis and tricarboxylic acid (TCA) cycle activity, was observed in cerebral cortex of GAD65 knockout mice....

  12. GABA/glutamate co-release controls habenula output and is modified by antidepressant treatment

    Science.gov (United States)

    Shabel, Steven J.; Proulx, Christophe D.; Piriz, Joaquin; Malinow, Roberto

    2015-01-01

    The lateral habenula (LHb), a key regulator of monoaminergic brain regions, is activated by negatively-valenced events. Its hyperactivity is associated with depression. While enhanced excitatory input to the LHb has been linked to depression, little is known about inhibitory transmission. We discovered that GABA is co-released with its functional opponent, glutamate, from long-range basal ganglia inputs (which signal negative events) to limit LHb activity in rodents. At this synapse, the balance of GABA/glutamate signaling is shifted towards reduced GABA in a model of depression and increased GABA by antidepressant treatment. GABA and glutamate co-release therefore controls LHb activity, and regulation of this remarkable form of transmission may be important for determining the impact of negative life events on mood and behavior. PMID:25237099

  13. Structural alterations of foreskin caused by chronic smoking may explain high levels of urethral reconstruction failure using foreskin flaps

    Directory of Open Access Journals (Sweden)

    João P. Rosado

    2012-08-01

    Full Text Available OBJECTIVES: The aim of the present study was to perform a stereological and biochemical analysis of the foreskin of smoker subjects. MATERIALS AND METHODS: Foreskin samples were obtained from 20 young adults (mean = 27.2 years old submitted to circumcision. Of the patients analyzed, one group (n = 10 had previous history of chronic smoking (a half pack to 3 packs per day for 3 to 13 years (mean = 5.8 ± 3.2. The control group included 10 nonsmoking patients. Masson's trichrome stain was used to quantify the foreskin vascular density. Weigert’s resorcin-fucsin stain was used to assess the elastic system fibers and Picrosirius red stain was applied to study the collagen. Stereological analysis was performed using the Image J software to determine the volumetric densities. For biochemical analysis, the total collagen was determined as µg of hydroxyproline per mg of dry tissue. Means were compared using the unpaired t-test (p < 0.05. RESULTS: Elastic system fibers of smokers was 42.5% higher than in the control group (p = 0.002. In contrast, smooth muscle fibers (p = 0.42 and vascular density (p = 0.16 did not show any significant variation. Qualitative analysis using Picrosirius red stain with polarized light evidenced the presence of type I and III collagen in the foreskin tissue, without significant difference between the groups. Total collagen concentration also did not differ significantly between smokers and non-smokers (73.1µg/mg ± 8.0 vs. 69.2µg/mg ± 5.9, respectively, p = 0.23. CONCLUSIONS: The foreskin tissue of smoking patients had a significant increase of elastic system fibers. Elastic fibers play an important role in this tissue’s turnover and this high concentration in smokers possibly causes high extensibility of the foreskin. The structural alterations in smokers’ foreskins could possibly explain the poor results in smoking patients submitted to foreskin fasciocutaneous flaps in urethral reconstruction surgery.

  14. Glutathione peroxidase 1 expression, malondialdehyde levels and histological alterations in the liver of Acrossocheilus fasciatus exposed to cadmium chloride.

    Science.gov (United States)

    Liu, Guo-Di; Sheng, Zhang; Wang, You-Fa; Han, Ying-Li; Zhou, Yang; Zhu, Jun-Quan

    2016-03-10

    Cadmium (Cd) is known as a widespread pollutant in aquatic environment. The accumulation of reactive oxygen species (ROS) is attributed to Cd exposure, which may affect the growth, development and physiological metabolism of aquatic organisms. In response to these unfavorable damages, antioxidant systems have been developed to protect against oxidative stress. In this study, we investigated the expression pattern of glutathione peroxidase 1 genes (GPx-1a and GPx-1b) in the liver of Acrossocheilus fasciatus after Cd administration. Total RNA extraction, reverse-transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE) were performed in order to clone the A. fasciatus GPx-1a and GPx-1b full-length cDNA sequences and partial fragment of β-actin cDNA from the liver for the first time. Tissue-specific expression analysis proved that GPx-1 genes were widely expressed in the liver, kidney, gill, testis, muscle, spleen, heart and brain. The changes of GPx-1 mRNA and malondialdehyde (MDA) levels in the liver treated with Cd were measured. In addition, the acute toxic effects of Cd on the microstructure of the liver were studied using light microscopy. These results suggest that GPx-1, MDA and liver histology which represent molecular, biochemical and histological levels, can be used as potential biomarkers to monitor Cd pollution. The overall findings also highlight the potential use of those three bio-indicators combined together as a multi-level tool (molecular, biochemical and histological levels) when monitoring Cd contamination and other possible exogenetic pollutants in aquatic environment. PMID:26707212

  15. Knowledge of Fecal Calprotectin and Infliximab Trough Levels Alters Clinical Decision-making for IBD Outpatients on Maintenance Infliximab Therapy

    OpenAIRE

    Huang, Vivian W; Prosser, Connie; Kroeker, Karen I.; Wang, Haili; Shalapay, Carol; Dhami, Neil; Fedorak, Darryl K; Halloran, Brendan; Dieleman, Levinus A.; Goodman, Karen J; Richard N Fedorak

    2015-01-01

    Background: Infliximab is an effective therapy for inflammatory bowel disease (IBD). However, more than 50% of patients lose response. Empiric dose intensification is not effective for all patients because not all patients have objective disease activity or subtherapeutic drug level. The aim was to determine how an objective marker of disease activity or therapeutic drug monitoring affects clinical decisions regarding maintenance infliximab therapy in outpatients with IBD. Methods: Consecutiv...

  16. Alteration of serum tumor necrosis factor-alpha level in gestational diabetes mellitus and correlation with insulin resistance

    International Nuclear Information System (INIS)

    Objective: To explore the dynamic of tumor necrosis factor-alpha (TNF-α)and its correlation with insulin resistance (IR)during different stages of gestational diabetes mellitus (GDM). Methods: Thirty-two subjects with GDM and 31 cases of normal pregnant women nonnal glucose tolerance, NGT were enrolled in the study, serum TNF-α and insulin were determined by radioimmunoassay. The plasma glucose was measured by using glucose oxidase. Tests repeated for each group according different stages of prenatal 25-28 weeks, 29-32 weeks, 37-38 weeks and postpartum 6-8 weeks. IR was assessed by the homeostasis model of assessment for insulin resistance index (HOMA-IR). Results: (1)Serum TNF-α levels in CDM and NGT group rose with gestational age, and both significantly decreased at postpartum. (2) Serum TNF-α levels in GDM of above-mentioned four stages respectively were (7.05±0.67) ng/L, (7.11± 0.75) ng/L, (7.36±0.79) ng/L, (5.46±0.37) ng/L respectively. All significantly increased than those in the same stage group (t=7.81, 7.05, 7.15, P<0.01). (3) Maternal serum TNF-α levels were in positive correlation with HOMA-IR in GDM (r=0.571, P<0.05). Conclusions: Serum TNF-α levels in GDM rose with gestational age, but significantly decreased at postpartum. The dynamic changes of serum TNF-α contribute to occurrence of insulin resistance. (authors)

  17. Epoxy fatty acids and inhibition of the soluble epoxide hydrolase selectively modulate GABA mediated neurotransmission to delay onset of seizures.

    Directory of Open Access Journals (Sweden)

    Bora Inceoglu

    Full Text Available In the brain, seizures lead to release of large amounts of polyunsaturated fatty acids including arachidonic acid (ARA. ARA is a substrate for three major enzymatic routes of metabolism by cyclooxygenase, lipoxygenase and cytochrome P450 enzymes. These enzymes convert ARA to potent lipid mediators including prostanoids, leukotrienes and epoxyeicosatrienoic acids (EETs. The prostanoids and leukotrienes are largely pro-inflammatory molecules that sensitize neurons whereas EETs are anti-inflammatory and reduce the excitability of neurons. Recent evidence suggests a GABA-related mode of action potentially mediated by neurosteroids. Here we tested this hypothesis using models of chemically induced seizures. The level of EETs in the brain was modulated by inhibiting the soluble epoxide hydrolase (sEH, the major enzyme that metabolizes EETs to inactive molecules, by genetic deletion of sEH and by direct administration of EETs into the brain. All three approaches delayed onset of seizures instigated by GABA antagonists but not seizures through other mechanisms. Inhibition of neurosteroid synthesis by finasteride partially blocked the anticonvulsant effects of sEH inhibitors while the efficacy of an inactive dose of neurosteroid allopregnanolone was enhanced by sEH inhibition. Consistent with earlier findings, levels of prostanoids in the brain were elevated. In contrast, levels of bioactive EpFAs were decreased following seizures. Overall these results demonstrate that EETs are natural molecules which suppress the tonic component of seizure related excitability through modulating the GABA activity and that exploration of the EET mediated signaling in the brain could yield alternative approaches to treat convulsive disorders.

  18. Long-term exposure to paraquat alters behavioral parameters and dopamine levels in adult zebrafish (Danio rerio).

    Science.gov (United States)

    Bortolotto, Josiane W; Cognato, Giana P; Christoff, Raissa R; Roesler, Laura N; Leite, Carlos E; Kist, Luiza W; Bogo, Mauricio R; Vianna, Monica R; Bonan, Carla D

    2014-04-01

    Chronic exposure to paraquat (Pq), a toxic herbicide, can result in Parkinsonian symptoms. This study evaluated the effect of the systemic administration of Pq on locomotion, learning and memory, social interaction, tyrosine hydroxylase (TH) expression, dopamine and 3,4-dihydroxyphenylacetic acid (DOPAC) levels, and dopamine transporter (DAT) gene expression in zebrafish. Adult zebrafish received an i.p. injection of either 10 mg/kg (Pq10) or 20 mg/kg (Pq20) of Pq every 3 days for a total of six injections. Locomotion and distance traveled decreased at 24 h after each injection in both treatment doses. In addition, both Pq10- and Pq20-treated animals exhibited differential effects on the absolute turn angle. Nonmotor behaviors were also evaluated, and no changes were observed in anxiety-related behaviors or social interactions in Pq-treated zebrafish. However, Pq-treated animals demonstrated impaired acquisition and consolidation of spatial memory in the Y-maze task. Interestingly, dopamine levels increased while DOPAC levels decreased in the zebrafish brain after both treatments. However, DAT expression decreased in the Pq10-treated group, and there was no change in the Pq20-treated group. The amount of TH protein showed no significant difference in the treated group. Our study establishes a new model to study Parkinson-associated symptoms in zebrafish that have been chronically treated with Pq. PMID:24568596

  19. Genetic variations altering FSH action affect circulating hormone levels as well as follicle growth in healthy peripubertal girls

    DEFF Research Database (Denmark)

    Busch, Alexander Siegfried; Hagen, Casper; Almstrup, Kristian;

    2016-01-01

    FSHR c.2039A>G alleles were positively associated with FSH levels in early-pubertal girls (B2 + B3, n = 327, r = 0.1, P = 0.02) and in young adolescents (B4 + B5, n = 149, r = 0.2, P = 0.01). Serum AMH and inhibin B levels were not significantly influenced by the single nucleotide polymorphisms (SNPs......). Single SNPs were not associated with follicles counts, however, a cumulative minor allele count (FSHB c.-211 G>T and FSHR c.-29G>A) was negatively associated with the number of large follicles (≥5 mm) (n = 91, P = 0.04) (adjusted for Tanner stages). LIMITATIONS, REASONS FOR CAUTION: Since we studied...... FSHR genetic variants and physiological as well as pathological conditions is being increasingly elucidated. The variant triplet set might serve as diagnostic and pharmacogenetic marker. For the first time, we show an additional effect of FSHR c.-29G>A on serum FSH levels in healthy girls. Moreover...

  20. Insulin signaling, lifespan and stress resistance are modulated by metabotropic GABA receptors on insulin producing cells in the brain of Drosophila.

    Science.gov (United States)

    Enell, Lina E; Kapan, Neval; Söderberg, Jeannette A E; Kahsai, Lily; Nässel, Dick R

    2010-01-01

    Insulin-like peptides (ILPs) regulate growth, reproduction, metabolic homeostasis, life span and stress resistance in worms, flies and mammals. A set of insulin producing cells (IPCs) in the Drosophila brain that express three ILPs (DILP2, 3 and 5) have been the main focus of interest in hormonal DILP signaling. Little is, however, known about factors that regulate DILP production and release by these IPCs. Here we show that the IPCs express the metabotropic GABA(B) receptor (GBR), but not the ionotropic GABA(A) receptor subunit RDL. Diminishing the GBR expression on these cells by targeted RNA interference abbreviates life span, decreases metabolic stress resistance and alters carbohydrate and lipid metabolism at stress, but not growth in Drosophila. A direct effect of diminishing GBR on IPCs is an increase in DILP immunofluorescence in these cells, an effect that is accentuated at starvation. Knockdown of irk3, possibly part of a G protein-activated inwardly rectifying K(+) channel that may link to GBRs, phenocopies GBR knockdown in starvation experiments. Our experiments suggest that the GBR is involved in inhibitory control of DILP production and release in adult flies at metabolic stress and that this receptor mediates a GABA signal from brain interneurons that may convey nutritional signals. This is the first demonstration of a neurotransmitter that inhibits insulin signaling in its regulation of metabolism, stress and life span in an invertebrate brain. PMID:21209905

  1. ADAMTS1 alters blood vessel morphology and TSP1 levels in LNCaP and LNCaP-19 prostate tumors

    International Nuclear Information System (INIS)

    Decreased expression of the angiogenesis inhibitor ADAMTS1 (ADAM metallopeptidase with thrombospondin type 1 motif, 1) has previously been reported during prostate cancer progression. The aim of this study was to investigate the function of ADAMTS1 in prostate tumors. ADAMTS1 was downregulated by shRNA technology in the human prostate cancer cell line LNCaP (androgen-dependent), originally expressing ADAMTS1, and was upregulated by transfection in its subline LNCaP-19 (androgen-independent), expressing low levels of ADAMTS1. Cells were implanted subcutaneously in nude mice and tumor growth, microvessel density (MVD), blood vessel morphology, pericyte coverage and thrombospondin 1 (TSP1) were studied in the tumor xenografts. Modified expression of ADAMTS1 resulted in altered blood vessel morphology in the tumors. Low expression levels of ADAMTS1 were associated with small diameter blood vessels both in LNCaP and LNCaP-19 tumors, while high levels of ADAMTS1 were associated with larger vessels. In addition, TSP1 levels in the tumor xenografts were inversely related to ADAMTS1 expression. MVD and pericyte coverage were not affected. Moreover, upregulation of ADAMTS1 inhibited tumor growth of LNCaP-19, as evidenced by delayed tumor establishment. In contrast, downregulation of ADAMTS1 in LNCaP resulted in reduced tumor growth rate. The present study demonstrates that ADAMTS1 is an important regulatory factor of angiogenesis and tumor growth in prostate tumors, where modified ADAMTS1 expression resulted in markedly changed blood vessel morphology, possibly related to altered TSP1 levels

  2. Canavanine Alters ROS/RNS Level and Leads to Post-translational Modification of Proteins in Roots of Tomato Seedlings

    Science.gov (United States)

    Krasuska, Urszula; Andrzejczak, Olga; Staszek, Paweł; Bogatek, Renata; Gniazdowska, Agnieszka

    2016-01-01

    Canavanine (CAN), a structural analog of arginine (Arg), is used as a selective inhibitor of inducible NOS in mammals. CAN is incorporated into proteins’ structure in the place of Arg, leading to the formation of aberrant compounds. This non-protein amino acid is found in legumes, e.g., Canavalia ensiformis (L.) DC. or Sutherlandia frutescens (L.) R.Br. and acts as a strong toxin against herbivores or plants. Tomato (Solanum lycopersicum L.) seedlings were treated for 24–72 h with CAN (10 or 50 μM) inhibiting root growth by 50 or 100%, without lethal effect. We determined ROS level/production in root extracts, fluorescence of DAF-FM and APF derivatives corresponding to RNS level in roots of tomato seedlings and linked CAN-induced restriction of root growth to the post-translational modifications (PTMs) of proteins: carbonylation and nitration. Both PTMs are stable markers of nitro-oxidative stress, regarded as the plant’s secondary response to phytotoxins. CAN enhanced H2O2 content and superoxide radicals generation in extracts of tomato roots and stimulated formation of protein carbonyl groups. An elevated level of carbonylated proteins was characteristic for the plants after 72 h of the culture, mainly for the roots exposed to 10 μM CAN. The proteolytic activity was stimulated by tested non-protein amino acid. CAN treatment led to decline of fluorescence of DAF-FM derivatives, and transiently stimulated fluorescence of APF derivatives. Short-term exposure of tomato seedlings to CAN lowered the protein nitration level. Activity of peroxidase, polyamine oxidase and NADPH oxidase, enzymes acting as modulators of H2O2 concentration and governing root architecture and growth were determined. Activities of all enzymes were stimulated by CAN, but no strict CAN concentration dependence was observed. We conclude, that although CAN treatment led to a decline in the nitric oxide level, PTMs observed in roots of plants exposed to CAN are linked rather to the

  3. Canavanine Alters ROS/RNS Level and Leads to Post-translational Modification of Proteins in Roots of Tomato Seedlings.

    Science.gov (United States)

    Krasuska, Urszula; Andrzejczak, Olga; Staszek, Paweł; Bogatek, Renata; Gniazdowska, Agnieszka

    2016-01-01

    Canavanine (CAN), a structural analog of arginine (Arg), is used as a selective inhibitor of inducible NOS in mammals. CAN is incorporated into proteins' structure in the place of Arg, leading to the formation of aberrant compounds. This non-protein amino acid is found in legumes, e.g., Canavalia ensiformis (L.) DC. or Sutherlandia frutescens (L.) R.Br. and acts as a strong toxin against herbivores or plants. Tomato (Solanum lycopersicum L.) seedlings were treated for 24-72 h with CAN (10 or 50 μM) inhibiting root growth by 50 or 100%, without lethal effect. We determined ROS level/production in root extracts, fluorescence of DAF-FM and APF derivatives corresponding to RNS level in roots of tomato seedlings and linked CAN-induced restriction of root growth to the post-translational modifications (PTMs) of proteins: carbonylation and nitration. Both PTMs are stable markers of nitro-oxidative stress, regarded as the plant's secondary response to phytotoxins. CAN enhanced H2O2 content and superoxide radicals generation in extracts of tomato roots and stimulated formation of protein carbonyl groups. An elevated level of carbonylated proteins was characteristic for the plants after 72 h of the culture, mainly for the roots exposed to 10 μM CAN. The proteolytic activity was stimulated by tested non-protein amino acid. CAN treatment led to decline of fluorescence of DAF-FM derivatives, and transiently stimulated fluorescence of APF derivatives. Short-term exposure of tomato seedlings to CAN lowered the protein nitration level. Activity of peroxidase, polyamine oxidase and NADPH oxidase, enzymes acting as modulators of H2O2 concentration and governing root architecture and growth were determined. Activities of all enzymes were stimulated by CAN, but no strict CAN concentration dependence was observed. We conclude, that although CAN treatment led to a decline in the nitric oxide level, PTMs observed in roots of plants exposed to CAN are linked rather to the formation of

  4. The Sushi Domains of Secreted GABA(B1) Isoforms Selectively Impair GABA(B) Heteroreceptor Function

    OpenAIRE

    Haller, Corinne; Bettler, Bernhard; Pless, Elin; Barlow, Paul N.; Gassmann, Martin; Rolink, Antonius G.; Tiao, Jim Y.; Metz, Michaela; Bradaia, Amyaouch; Biermann, Barbara; Kaupmann, Klemens

    2008-01-01

    GABAB receptors are the G-protein-coupled receptors for γ-aminobutyric acid (GABA), the main inhibitory neurotransmitter in the brain. GABAB receptors are promising drug targets for a wide spectrum of psychiatric and neurological disorders. Receptor subtypes exhibit no pharmacological differences and are based on the subunit isoforms GABAB1a and GABAB1b. GABAB1a differs from GABAB1b in its ectodomain by the presence of a pair of conserved protein binding motifs, the sushi domains (SDs). Previ...

  5. Anaesthetic impairment of immune function is mediated via GABA(A receptors.

    Directory of Open Access Journals (Sweden)

    Daniel W Wheeler

    Full Text Available GABA(A receptors are members of the Cys-loop family of neurotransmitter receptors, proteins which are responsible for fast synaptic transmission, and are the site of action of wide range of drugs. Recent work has shown that Cys-loop receptors are present on immune cells, but their physiological roles and the effects of drugs that modify their function in the innate immune system are currently unclear. We are interested in how and why anaesthetics increase infections in intensive care patients; a serious problem as more than 50% of patients with severe sepsis will die. As many anaesthetics act via GABA(A receptors, the aim of this study was to determine if these receptors are present on immune cells, and could play a role in immunocompromising patients.We demonstrate, using RT-PCR, that monocytes express GABA(A receptors constructed of α1, α4, β2, γ1 and/or δ subunits. Whole cell patch clamp electrophysiological studies show that GABA can activate these receptors, resulting in the opening of a chloride-selective channel; activation is inhibited by the GABA(A receptor antagonists bicuculline and picrotoxin, but not enhanced by the positive modulator diazepam. The anaesthetic drugs propofol and thiopental, which can act via GABA(A receptors, impaired monocyte function in classic immunological chemotaxis and phagocytosis assays, an effect reversed by bicuculline and picrotoxin.Our results show that functional GABA(A receptors are present on monocytes with properties similar to CNS GABA(A receptors. The functional data provide a possible explanation as to why chronic propofol and thiopental administration can increase the risk of infection in critically ill patients: their action on GABA(A receptors inhibits normal monocyte behaviour. The data also suggest a potential solution: monocyte GABA(A receptors are insensitive to diazepam, thus the use of benzodiazepines as an alternative anesthetising agent may be advantageous where infection is a life

  6. A moderate elevation of circulating levels of IGF-I does not alter ErbB2 induced mammary tumorigenesis

    International Nuclear Information System (INIS)

    Epidemiological evidence suggests that moderately elevated levels of circulating insulin-like growth factor-I (IGF-I) are associated with increased risk of breast cancer in women. How circulating IGF-I may promote breast cancer incidence is unknown, however, increased IGF-I signaling is linked to trastuzumab resistance in ErbB2 positive breast cancer. Few models have directly examined the effect of moderately high levels of circulating IGF-I on breast cancer initiation and progression. The purpose of this study was to assess the ability of circulating IGF-I to independently initiate mammary tumorigenesis and/or accelerate the progression of ErbB2 mediated mammary tumor growth. We crossed heterozygous TTR-IGF-I mice with heterozygous MMTV-ErbB2 mice to generate 4 different genotypes: TTR-IGF-I/MMTV-ErbB2 (bigenic), TTR-IGF-I only, MMTV-ErbB2 only, and wild type (wt). Virgin females were palpated twice a week and harvested when tumors reached 1000 mm3. For study of normal development, blood and tissue were harvested at 4, 6 and 9 weeks of age in TTR-IGF-I and wt mice. TTR-IGF-I and TTR-IGF-I/ErbB2 bigenic mice showed a moderate 35% increase in circulating total IGF-I compared to ErbB2 and wt control mice. Elevation of circulating IGF-I had no effect upon pubertal mammary gland development. The transgenic increase in IGF-I alone wasn't sufficient to initiate mammary tumorigenesis. Elevated circulating IGF-I had no effect upon ErbB2-induced mammary tumorigenesis or metastasis, with median time to tumor formation being 30 wks and 33 wks in TTR-IGF-I/ErbB2 bigenic and ErbB2 mice respectively (p = 0.65). Levels of IGF-I in lysates from ErbB2/TTR-IGF-I tumors compared to ErbB2 was elevated in a similar manner to the circulating IGF-I, however, there was no effect on the rate of tumor growth (p = 0.23). There were no morphological differences in tumor type (solid adenocarcinomas) between bigenic and ErbB2 mammary glands. Using the first transgenic animal model to

  7. A gain-of-function mutation in IAA8 alters Arabidopsis floral organ development by change of jasmonic acid level.

    Science.gov (United States)

    Wang, Jing; Yan, Da-Wei; Yuan, Ting-Ting; Gao, Xiang; Lu, Ying-Tang

    2013-05-01

    Auxin regulates a variety of physiological processes via its downstream factors included Aux/IAAs. In this study, one of these Aux/IAAs, IAA8 is shown to play its role in Arabidopsis development with transgenic plants expressing GFP-mIAA8 under the control of IAA8 promoter, in which IAA8 protein was mutated by changing Pro170 to Leu170 in its conserved domain II. These transgenic dwarfed plants had more lateral branches, short primary inflorescence stems, decreased shoot apical dominance, curled leaves and abnormal flower organs (short petal and stamen, and bent stigmas). Further experiments revealed that IAA8::GFP-mIAA8 plants functioned as gain-of-function mutation to increase GFP-mIAA8 amount probably by stabilizing IAA8 protein against proteasome-mediated protein degradation with IAA8::GFP-IAA8 plants as control. The searching for its downstream factors indicated its interaction with both ARF6 and ARF8, suggesting that IAA8 may involve in flower organ development. This was further evidenced by analyzing the expression of jasmonic acid (JA) biosynthetic genes and JA levels because ARF6 and ARF8 are required for normal JA production. These results indicated that in IAA8::GFP-mIAA8 plants, JA biosynthetic genes including DAD1 (AT2G44810), AOS (AT5G42650) and ORP3 (AT2G06050) were dramatically down-regulated and JA level in the flowers was reduced to 70 % of that in wild-type. Furthermore, exogenous JA application can partially rescue short petal and stamen observed IAA8::GFP-mIAA8 plants. Thus, IAA8 plays its role in floral organ development by changes in JA levels probably via its interaction with ARF6/8 proteins. PMID:23483289

  8. Metal-supplemented diets alter carbohydrate levels in tissue and hemolymph of gypsy moth larvae (Lymantria dispar, Lymantriidae, Lepidoptera)

    Energy Technology Data Exchange (ETDEWEB)

    Ortel, J. [Univ. of Vienna (Austria)

    1996-07-01

    Larvae of Lymantria dispar were exposed to two concentrations each of Cd, Pb, Cu, and Zn from hatching to day 3 of the fourth instar. The metals were applied via artificial diet (wheat germ diet); two control groups were reared on either an uncontaminated artificial diet (C) or on a natural diet (oak leaves, EF). High-pressure liquid chromatography (HPLC) was employed to analyze the hemolymph carbohydrates, whereas body glycogen and glucose were determined enzymatically. The results were analyzed with respect to diet-specific differences (oak leaves versus wheat germ diet) and metal exposure compared with the uncontaminated artificial diet. Hemolymph trehalose levels were higher in oak leaf-reared individuals than in those fed on the wheat germ diet (p < 0.01), whereas the opposite applied to the body glycogen and free glucose levels (p < 0.01). The average trehalose value of the control (C) (4.3 mg/ml) was reduced by metal contamination, dependent on both the metal itself and the concentration (Cd, Cu, Zn; 1.4--3.3 mg/ml). Sorbitol was not detected in the hemolymph of EF specimens, whereas it occurred in all artificial diet-fed groups. Metal- and dose-dependent differences in the hemolymph sorbitol levels were observed in the treatment groups, but not in the controls. Glycogen content increased in the low concentration of Cd, Pb, and Cu, whereas a decrease was observed for the low Cd and both Zn concentrations. Tissue free glucose was enhanced only in three of the metal groups. Generally, fresh and dry weights of larvae were reduced in all groups except the high Cu-contaminated one. The results may indicate that mass outbreaks of an important forest pest insect like L. dispar may be facilitated in metal-contaminated areas because parasitization success of antagonistic species may decline due to deterioration of nourishment within the metal-stressed host.

  9. Alterations in brain leptin signalling in spite of unchanged CSF leptin levels in Alzheimer’s disease

    OpenAIRE

    S. MAIOLI; Lodeiro, M. (María); Merino-Serrais, P.; Falahati, F.; Khan, W.; Puerta, E. (Elena); Codita, A. (Alina); Rimondini, R.; Ramirez, M.J. (María Javier); Simmons, A.; Gil-Bea, F J; Westman, E.; Cedazo-Minguez, A.

    2014-01-01

    Several studies support the relation between leptin and Alzheimer’s disease (AD). We show that leptin levels in CSF are unchanged as subjects progress to AD. However, in AD hippocampus, leptin signalling was decreased and leptin localization was shifted, being more abundant in reactive astrocytes and less in neurons. Similar translocation of leptin was found in brains from Tg2576 and apoE4 mice. Moreover, an enhancement of leptin receptors was found in hippocampus of young Tg2576 mice and in ...

  10. Characterizing dose response relationships: Chronic gamma radiation in Lemna minor induces oxidative stress and altered polyploidy level.

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-12-01

    The biological effects and interactions of different radiation types in plants are still far from understood. Among different radiation types, external gamma radiation treatments have been mostly studied to assess the biological impact of radiation toxicity in organisms. Upon exposure of plants to gamma radiation, ionisation events can cause, either directly or indirectly, severe biological damage to DNA and other biomolecules. However, the biological responses and oxidative stress related mechanisms under chronic radiation conditions are poorly understood in plant systems. In the following study, it was questioned if the Lemna minor growth inhibition test is a suitable approach to also assess the radiotoxicity of this freshwater plant. Therefore, L. minor plants were continuously exposed for seven days to 12 different dose rate levels covering almost six orders of magnitude starting from 80 μGy h(-1) up to 1.5 Gy h(-1). Subsequently, growth, antioxidative defence system and genomic responses of L. minor plants were evaluated. Although L. minor plants could survive the exposure treatment at environmental relevant exposure conditions, higher dose rate levels induced dose dependent growth inhibitions starting from approximately 27 mGy h(-1). A ten-percentage growth inhibition of frond area Effective Dose Rate (EDR10) was estimated at 95 ± 7 mGy h(-1), followed by 153 ± 13 mGy h(-1) and 169 ± 12 mGy h(-1) on fresh weight and frond number, respectively. Up to a dose rate of approximately 5 mGy h(-1), antioxidative enzymes and metabolites remained unaffected in plants. A significant change in catalase enzyme activity was found at 27 mGy h(-1) which was accompanied with significant increases of other antioxidative enzyme activities and shifts in ascorbate and glutathione content at higher dose rate levels, indicating an increase in oxidative stress in plants. Recent plant research hypothesized that environmental genotoxic stress conditions

  11. Involvement of heparan sulfate 6-O-sulfation in the regulation of energy metabolism and the alteration of thyroid hormone levels in male mice.

    Science.gov (United States)

    Nagai, Naoko; Habuchi, Hiroko; Sugaya, Noriko; Nakamura, Masao; Imamura, Toru; Watanabe, Hideto; Kimata, Koji

    2013-08-01

    Here, we report that male heparan sulfate 6-O-sulfotransferase-2 (Hs6st2) knockout mice showed increased body weight in an age-dependent manner even when fed with a normal diet and showed a phenotype of impaired glucose metabolism and insulin resistance. Quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis showed that the expression of mitochondrial uncoupling proteins Ucp1 and Ucp3 was reduced in the interscapular brown adipose tissue (BAT) of male Hs6st2 knockout mice, suggesting reduced energy metabolism. The serum level of thyroid-stimulating hormone was significantly higher and that of thyroxine was lower in the knockout mice. When cultures of brown adipocytes from wild-type and Hs6st2 knockout mice isolated and differentiated in vitro were treated with FGF19 (fibroblast growth factor 19) or FGF21 in the presence or the absence of heparitinase I, phosphorylation of p42/p44 mitogen-activated protein (MAP) kinase was reduced. Heparan sulfate (HS) 6-O-sulfation was reduced not only in BAT but also in the thyroid tissue of the knockout mice. Thus, 6-O-sulfation in HS seems to play an important role in mediating energy metabolism by controlling thyroid hormone levels and signals from the FGF19 subfamily proteins, and the alteration of the HS composition may result in metabolic syndrome phenotypes such as altered glucose and insulin tolerance. PMID:23690091

  12. Histopathological alterations, biochemical responses and acetylcholinesterase levels in Clarias gariepinus as biomarkers of exposure to organophosphates pesticides.

    Science.gov (United States)

    Doherty, V F; Ladipo, M K; Aneyo, I A; Adeola, A; Odulele, W Y

    2016-05-01

    Organophosphate pesticides, commonly used in large scale farming, have been found to be major contaminants in aquatic environment. Clarias gariepinus was exposed to acute and sublethal concentrations of phostoxin and DD Force to evaluate single and joint action toxicity of the organophosphates. Effects of phostoxin and DD force on antioxidant enzymes, fish organs and acetylcholinesterase levels in fingerlings and juveniles of C. gariepinus were also investigated. The lethal concentrations (96 h LC50) for phostoxin and DD Force were 0.631 and 1.759 mg/l, respectively. The results obtained from the bioassay showed that phostoxin was 2.8× more toxic than DD Force after exposure of C. gariepinus. Joint action toxicity evaluations of phostoxin and DD Force showed that the interaction between the chemicals was synergistic (RTU >1). The biochemical responses in the exposed fish differed significantly (P toxicity studies, respiratory stress, erratic swimming and instant death of fish were observed in the exposed fish. This study reveals that changes in histopathology and acetylcholinesterase level are good biomarkers and can be successfully used to detect exposure to organophosphates pesticides in fish. PMID:27121169

  13. Glucose concentration alters dissolved oxygen levels in liquid cultures of Beauveria bassiana and affects formation and bioefficacy of blastospores.

    Science.gov (United States)

    Mascarin, Gabriel Moura; Jackson, Mark A; Kobori, Nilce Naomi; Behle, Robert W; Dunlap, Christopher A; Delalibera Júnior, Ítalo

    2015-08-01

    The filamentous fungus Beauveria bassiana is an economically important pathogen of numerous arthropod pests and is able to grow in submerged culture as filaments (mycelia) or as budding yeast-like blastospores. In this study, we evaluated the effect of dissolved oxygen and high glucose concentrations on blastospore production by submerged cultures of two isolates of B. bassiana, ESALQ1432 and GHA. Results showed that maintaining adequate dissolved oxygen levels coupled with high glucose concentrations enhanced blastospore yields by both isolates. High glucose concentrations increased the osmotic pressure of the media and coincided with higher dissolved oxygen levels and increased production of significantly smaller blastospores compared with blastospores produced in media with lower concentrations of glucose. The desiccation tolerance of blastospores dried to less than 2.6 % moisture was not affected by the glucose concentration of the medium but was isolate dependent. Blastospores of isolate ESALQ1432 produced in media containing 140 g glucose L(-1) showed greater virulence toward whitefly nymphs (Bemisia tabaci) as compared with blastospores produced in media containing 40 g glucose L(-1). These results suggest a synergistic effect between glucose concentration and oxygen availability on changing morphology and enhancing the yield and efficacy of blastospores of B. bassiana, thereby facilitating the development of a cost-effective production method for this blastospore-based bioinsecticide. PMID:25947245

  14. Naproxen, a Nonsteroidal Anti-Inflammatory Drug, Can Affect Daily Hypobaric Hypoxia-Induced Alterations of Monoamine Levels in Different Areas of the Brain in Male Rats.

    Science.gov (United States)

    Goswami, Ananda Raj; Dutta, Goutam; Ghosh, Tusharkanti

    2016-06-01

    Goswami, Ananda Raj, Goutam Dutta, and Tusharkanti Ghosh. Naproxen, a nonsteroidal anti-inflammatory drug can affect daily hypobaric hypoxia-induced alterations of monoamine levels in different areas of the brain in male rats. High Alt Med Biol. 17:133-140, 2016.-The oxidative stress (OS)-induced prostaglandin (PG) release, in hypobaric hypoxic (HHc) condition, may be linked with the changes of brain monoamines. The present study intends to explore the changes of monoamines in hypothalamus (H), cerebral cortex (CC), and cerebellum (CB) along with the motor activity in rats after exposing them to simulated hypobaric condition and the role of PGs on the daily hypobaric hypoxia (DHH)-induced alteration of brain monoamines by administering, an inhibitor of PG synthesis, naproxen. The rats were exposed to a decompression chamber at 18,000 ft for 8 hours per day for 6 days after administration of vehicle or naproxen (18 mg/kg body wt.). The monoamine levels (epinephrine, E; norepinephrine, NE; dopamine, DA; and 5-hydroxytryptamine, 5-HT) in CC, CB, and H were assayed by high-performance liquid chromatography (HPLC) with electrochemical detection, and the locomotor behavior was measured by open field test. The NE and DA levels were decreased in CC, CB, and H of the rat brain in HHc condition. The E and 5-HT levels were decreased in CC, but in H and CB, they remained unaltered in HHc condition. These DHH-induced changes of monoamines in brain areas were prevented after administration of naproxen in HHc condition. The locomotor behavior remained unaltered in HHc condition and after administration of naproxen in HHc condition. The DHH-induced changes of monoamines in the brain in HHc condition are probably linked with PGs that may be induced by OS. PMID:26894935

  15. Tris(2-butoxyethyl)phosphate and triethyl phosphate alter embryonic development, hepatic mRNA expression, thyroid hormone levels, and circulating bile acid concentrations in chicken embryos

    International Nuclear Information System (INIS)

    The organophosphate flame retardants tris(2-butoxyethyl) phosphate (TBOEP) and triethyl phosphate (TEP) are used in a wide range of applications to suppress or delay the ignition and spread of fire. Both compounds have been detected in the environment and TBOEP was recently measured in free-living avian species. In this study, TBOEP and TEP were injected into the air cell of chicken embryos at concentrations ranging from 0 to 45,400 ng/g and 0 to 241,500 ng/g egg, respectively. Pipping success, development, hepatic mRNA expression of 9 target genes, thyroid hormone levels, and circulating bile acid concentrations were determined. Exposure to the highest doses of TBOEP and TEP resulted in negligible detection of the parent compounds in embryonic contents at pipping indicating their complete metabolic degradation. TBOEP exposure had limited effects on chicken embryos, with the exception of hepatic CYP3A37 mRNA induction. TEP exposure decreased pipping success to 68%, altered growth, increased liver somatic index (LSI) and plasma bile acids, and modulated genes associated with xenobiotic and lipid metabolism and the thyroid hormone pathway. Plasma thyroxine levels were decreased at all TEP doses, including an environmentally-relevant concentration (8 ng/g), and gallbladder hypotrophy was evident at ≥ 43,200 ng/g. Tarsus length and circulating thyroxine concentration emerged as potential phenotypic anchors for the modulation of transthyretin mRNA. The increase in plasma bile acids and LSI, gallbladder hypotrophy, and discoloration of liver tissue represented potential phenotypic outcomes associated with modulation of hepatic genes involved with xenobiotic and lipid metabolism. - Highlights: • TBOEP is not embryolethal to chicken embryos. • TEP affected embryonic viability, morphometric endpoints, and thyroid hormone levels. • TEP altered mRNA levels of xenobiotic and lipid metabolism genes. • TEP increased plasma bile acids and caused gallbladder hypotrophy

  16. Tris(2-butoxyethyl)phosphate and triethyl phosphate alter embryonic development, hepatic mRNA expression, thyroid hormone levels, and circulating bile acid concentrations in chicken embryos

    Energy Technology Data Exchange (ETDEWEB)

    Egloff, Caroline [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Crump, Doug, E-mail: doug.crump@ec.gc.ca [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Porter, Emily; Williams, Kim L.; Letcher, Robert J.; Gauthier, Lewis T. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Kennedy, Sean W. [National Wildlife Research Centre, Environment Canada, Ottawa, ON K1A 0H3 (Canada); Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5 (Canada)

    2014-09-15

    The organophosphate flame retardants tris(2-butoxyethyl) phosphate (TBOEP) and triethyl phosphate (TEP) are used in a wide range of applications to suppress or delay the ignition and spread of fire. Both compounds have been detected in the environment and TBOEP was recently measured in free-living avian species. In this study, TBOEP and TEP were injected into the air cell of chicken embryos at concentrations ranging from 0 to 45,400 ng/g and 0 to 241,500 ng/g egg, respectively. Pipping success, development, hepatic mRNA expression of 9 target genes, thyroid hormone levels, and circulating bile acid concentrations were determined. Exposure to the highest doses of TBOEP and TEP resulted in negligible detection of the parent compounds in embryonic contents at pipping indicating their complete metabolic degradation. TBOEP exposure had limited effects on chicken embryos, with the exception of hepatic CYP3A37 mRNA induction. TEP exposure decreased pipping success to 68%, altered growth, increased liver somatic index (LSI) and plasma bile acids, and modulated genes associated with xenobiotic and lipid metabolism and the thyroid hormone pathway. Plasma thyroxine levels were decreased at all TEP doses, including an environmentally-relevant concentration (8 ng/g), and gallbladder hypotrophy was evident at ≥ 43,200 ng/g. Tarsus length and circulating thyroxine concentration emerged as potential phenotypic anchors for the modulation of transthyretin mRNA. The increase in plasma bile acids and LSI, gallbladder hypotrophy, and discoloration of liver tissue represented potential phenotypic outcomes associated with modulation of hepatic genes involved with xenobiotic and lipid metabolism. - Highlights: • TBOEP is not embryolethal to chicken embryos. • TEP affected embryonic viability, morphometric endpoints, and thyroid hormone levels. • TEP altered mRNA levels of xenobiotic and lipid metabolism genes. • TEP increased plasma bile acids and caused gallbladder hypotrophy

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

    Directory of Open Access Journals (Sweden)

    Robichon Alain

    2004-06-01

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

  18. Plasma glucagon-like peptide 1 and peptide YY levels are not altered in symptomatic fructose-sorbitol malabsorption

    DEFF Research Database (Denmark)

    Valeur, Jørgen; Øines, Eliann; Morken, Mette Helvik; Holst, Jens Juul; Berstad, Arnold

    2008-01-01

    excretion and plasma glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) levels were measured during the next 3 h. Both habitual and post-test symptoms were assessed. RESULTS: Malabsorption of fructose and sorbitol was present in 61% of the patients and 73% of the controls. Nevertheless, the patients......OBJECTIVE: Carbohydrate malabsorption causes more symptoms in patients with functional gastrointestinal disorders than in healthy individuals. The purpose of this study was to investigate whether this could be explained by differences in ileal brake hormone secretion. MATERIAL AND METHODS: Eighteen...... consecutive patients with functional abdominal complaints, referred to our clinic for investigation of self-reported food hypersensitivity, were included in the study and compared with 15 healthy volunteers. All subjects ingested a mixture of 25 g fructose and 5 g sorbitol. Pulmonary hydrogen and methane...

  19. Altered circulating levels of matrix metalloproteinases and inhibitors associated with elevated type 2 cytokines in lymphatic filarial disease.

    Directory of Open Access Journals (Sweden)

    Rajamanickam Anuradha

    Full Text Available BACKGROUND: Infection with Wuchereria bancrofti can cause severe disease characterized by subcutaneous fibrosis and extracellular matrix remodeling. Matrix metalloproteinases (MMPs are a family of enzymes governing extracellular remodeling by regulating cellular homeostasis, inflammation, and tissue reorganization, while tissue-inhibitors of metalloproteinases (TIMPs are endogenous regulators of MMPs. Homeostatic as well as inflammation-induced balance between MMPs and TIMPs is considered critical in mediating tissue pathology. METHODS: To elucidate the role of MMPs and TIMPs in filarial pathology, we compared the plasma levels of a panel of MMPs, TIMPs, other pro-fibrotic factors, and cytokines in individuals with chronic filarial pathology with (CP Ag+ or without (CP Ag- active infection to those with clinically asymptomatic infections (INF and in those without infection (endemic normal [EN]. Markers of pathogenesis were delineated based on comparisons between the two actively infected groups (CP Ag+ compared to INF and those without active infection (CP Ag- compared to EN. RESULTS AND CONCLUSION: Our data reveal that an increase in circulating levels of MMPs and TIMPs is characteristic of the filarial disease process per se and not of active infection; however, filarial disease with active infection is specifically associated with increased ratios of MMP1/TIMP4 and MMP8/TIMP4 as well as with pro-fibrotic cytokines (IL-5, IL-13 and TGF-β. Our data therefore suggest that while filarial lymphatic disease is characterized by a non-specific increase in plasma MMPs and TIMPs, the balance between MMPs and TIMPs is an important factor in regulating tissue pathology during active infection.

  20. Toxicity of canavanine in tomato (Solanum lycopersicum L.) roots is due to alterations in RNS, ROS and auxin levels.

    Science.gov (United States)

    Krasuska, Urszula; Andrzejczak, Olga; Staszek, Paweł; Borucki, Wojciech; Gniazdowska, Agnieszka

    2016-06-01

    Canavanine (CAN) is non-proteinogenic aminoacid and a structural analog of arginine (Arg). Naturally, CAN occurs in legumes e.g. jack bean and is considered as a strong allelochemical. As a selective inhibitor of inducible nitric oxide synthase in mammalians, it could act as a modifier of nitric oxide (NO) concentration in plants. Modifications in the content of endogenous reactive nitrogen species (RNS) and reactive oxygen species (ROS) influence root structure and architecture, being also under hormonal control. The aim of the work was to investigate regulation of root growth in tomato (Solanum lycopersicum L. cv. Malinowy Ożarowski) seedling by application of CAN at concentration (10 and 50 μM) leading to 50% or 100% restriction of root elongation. CAN at higher concentration led to slight DNA fragmentation, increased total RNA and protein level. Decline in total respiration rate after CAN supplementation was not associated with enhanced membrane permeability. Malformations in root morphology (shorter and thicker roots, limited number of lateral roots) were accompanied by modification in NO and ONOO(-) localization; determined mainly in peridermal cells and some border cells. Although, CAN resulted in low RNS production, addition of exogenous NO by usage of NO donors did not reverse its negative effect, nor recovery effect was detected after roots imbibition in Arg. To build up a comprehensive view on mode of action of CAN as root growth inhibitor, it was shown an elevated level of auxin. To summarize, we demonstrated several secondary mode of action of CAN, indicating its toxicity in plants linked to restriction in RNS formation accompanied by simultaneous overaccumulation of ROS. PMID:26986929

  1. Natural Functional SNPs in miR-155 Alter Its Expression Level, Blood Cell Counts, and Immune Responses

    Science.gov (United States)

    Li, Congcong; He, Huabin; Liu, An; Liu, Huazhen; Huang, Haibo; Zhao, Changzhi; Jing, Lu; Ni, Juan; Yin, Lilin; Hu, Suqin; Wu, Hui; Li, Xinyun; Zhao, Shuhong

    2016-01-01

    miR-155 has been confirmed to be a key factor in immune responses in humans and other mammals. Therefore, investigation of variations in miR-155 could be useful for understanding the differences in immunity between individuals. In this study, four SNPs in miR-155 were identified in mice (Mus musculus) and humans (Homo sapiens). In mice, the four SNPs were closely linked and formed two miR-155 haplotypes (A and B). Ten distinct types of blood parameters were associated with miR-155 expression under normal conditions. Additionally, 4 and 14 blood parameters were significantly different between these two genotypes under normal and lipopolysaccharide (LPS) stimulation conditions, respectively. Moreover, the expression levels of miR-155, the inflammatory response to LPS stimulation, and the lethal ratio following Salmonella typhimurium infection were significantly increased in mice harboring the AA genotype. Further, two SNPs, one in the loop region and the other near the 3′ terminal of pre-miR-155, were confirmed to be responsible for the differential expression of miR-155 in mice. Interestingly, two additional SNPs, one in the loop region and the other in the middle of miR-155*, modulated the function of miR-155 in humans. Predictions of secondary RNA structure using RNAfold showed that these SNPs affected the structure of miR-155 in both mice and humans. Our results provide novel evidence of the natural functional SNPs of miR-155 in both mice and humans, which may affect the expression levels of mature miR-155 by modulating its secondary structure. The SNPs of human miR-155 may be considered as causal mutations for some immune-related diseases in the clinic. The two genotypes of mice could be used as natural models for studying the mechanisms of immune diseases caused by abnormal expression of miR-155 in humans. PMID:27532002

  2. Unpredictable neonatal stress enhances adult anxiety and alters amygdala gene expression related to serotonin and GABA

    OpenAIRE

    Sarro, Emma C.; Sullivan, Regina M.; Barr, Gordon

    2013-01-01

    Anxiety-related disorders are among the most common psychiatric illnesses, thought to have both genetic and environmental causes. Early-life trauma, such as abuse from a caregiver, can be predictable or unpredictable, each resulting in increased prevalence and severity of a unique set of disorders. In this study, we examined the influence of early unpredictable trauma on both the behavioral expression of adult anxiety and gene expression within the amygdala. Neonatal rats were exposed to unpa...

  3. Role of altered esophageal intraluminal baseline impedance levels in patients with gatroesophageal reflux disease refractory to proton pump inhibitors.

    Science.gov (United States)

    Jiang, Liuqin; Ye, Bixing; Lin, Lin; Wang, Ying; Wang, Meifeng

    2016-08-01

    Numerous studies have investigated utility of esophageal intraluminal baseline impedance levels (BILs) in gastroesophageal reflux disease (GERD). However, effect of BILs in refractory GERD (RGERD) has not been well investigated. The aim of this study is to evaluate role of BILs in RGERD patients. Total 62 subjects with refractory gastroesophageal reflux symptoms underwent 24-hour impedance-pH monitoring and gastroendoscopy. Distal BILs in acid reflux type were significantly lower than those in nonacid reflux type and functional heartburn (FH) group. Distal BILs of reflux esophagitis (RE) patients were lower than those of nonerosive reflux disease (NERD) patients, while there were no statistical significance between 2 groups. Patients with severe esophagitis had lower distal BILs than those with mild esophagitis and NERD patients, and patients with severe esophagitis in acid reflux type had the lowest distal BILs. Distal BILs were significantly negatively correlated with DeMeester score, episodes of acid reflux, and acid exposure time, but no correlated with episodes of nonacid reflux. Characteristics of BILs in RGERD patients were similar with those in GERD patients, but might be more complicated. Evaluating BILs in RGERD patients could achieve a better understanding of pathophysiology in RGERD. PMID:27537561

  4. Biphasic GABA-A receptor-mediated effect on the spontaneous activity of the circular layer in cat terminal ileum.

    Science.gov (United States)

    Pencheva, N; Radomirov, R

    1993-07-01

    1. The GABA and GABA-A receptor agonist muscimol changed the spontaneous mechanical activity of a circular layer isolated from cat terminal ileum, while the selective GABA-B receptor agonist (+/-)baclofen had no effect. 2. GABA at doses ranging from 1 microM to 2 mM elicited concentration-dependent biphasic responses which consisted of a relaxation followed by contraction, with a tonic and a phasic component. The EC50 values, calculated at 95% confidence limits (CL), were 94.9 microM (83.5-109.8 microM) and 66.0 microM (51.2-75.5 microM) for the relaxation and contractile phases, respectively. 3. The GABA-induced biphasic responses were sensitive to bicuculline and picrotoxinin and were entirely mimicked by muscimol. Bicuculline competitively antagonized the effects of GABA and gave closely similar pA2 values for both phases of these responses--inhibitory and stimulatory. Cross-desensitization occurred only between GABA and muscimol and not between (+/-)baclofen and GABA, or (+/-)baclofen and muscimol. 4. Both bicuculline-sensitive phases evoked by GABA and muscimol were abolished by tetrodotoxin or atropine, but were unaffected by guanethidine or naloxone. 5. The present results suggested that the biphasic GABA effect on the mechanical activity of the circular layer in cat terminal ileum was mediated by prejunctional GABA-A receptors, most probably through an action on the cholinergic pathway. PMID:8224749

  5. Regulation of (/sup 3/H)GABA release from strips of guinea pig urinary bladder

    Energy Technology Data Exchange (ETDEWEB)

    Shirakawa, J.; Taniyama, K.; Iwai, S.; Tanaka, C.

    1988-12-01

    The presence of receptors that regulate the release of gamma-aminobutyric acid (GABA) was studied in strips of the guinea pig urinary bladder. GABA (10(-8)-10(-5) M) and muscimol (10(-8)-10(-5) M), but not baclofen (10(-5) M), reduced the Ca2+-dependent, tetrodotoxin-resistant release of (/sup 3/H)GABA evoked by high K+ from the urinary bladder strips preloaded with (/sup 3/H)GABA. The inhibitory effect of muscimol was antagonized by bicuculline and potentiated by diazepam, clonazepam, and pentobarbital sodium. The potentiating effect of clonazepam was antagonized by Ro 15-1788. Acetylcholine (ACh) inhibited the high K+-evoked release of (/sup 3/H)GABA. The inhibitory effect of ACh was antagonized by atropine sulfate and pirenzepine but not by hexamethonium. Norepinephrine (NE) inhibited the evoked release of (/sup 3/H)GABA. The inhibitory effect of NE was mimicked by clonidine, but not by phenylephrine, and was antagonized by yohimbine but not by prazosin. These results provide evidence that the release of GABA from strips of guinea pig urinary bladder is regulated via the bicuculline-sensitive GABAA receptor, M1-muscarinic, and alpha 2-adrenergic receptors.

  6. Regulation of [3H]GABA release from strips of guinea pig urinary bladder

    International Nuclear Information System (INIS)

    The presence of receptors that regulate the release of gamma-aminobutyric acid (GABA) was studied in strips of the guinea pig urinary bladder. GABA (10(-8)-10(-5) M) and muscimol (10(-8)-10(-5) M), but not baclofen (10(-5) M), reduced the Ca2+-dependent, tetrodotoxin-resistant release of [3H]GABA evoked by high K+ from the urinary bladder strips preloaded with [3H]GABA. The inhibitory effect of muscimol was antagonized by bicuculline and potentiated by diazepam, clonazepam, and pentobarbital sodium. The potentiating effect of clonazepam was antagonized by Ro 15-1788. Acetylcholine (ACh) inhibited the high K+-evoked release of [3H]GABA. The inhibitory effect of ACh was antagonized by atropine sulfate and pirenzepine but not by hexamethonium. Norepinephrine (NE) inhibited the evoked release of [3H]GABA. The inhibitory effect of NE was mimicked by clonidine, but not by phenylephrine, and was antagonized by yohimbine but not by prazosin. These results provide evidence that the release of GABA from strips of guinea pig urinary bladder is regulated via the bicuculline-sensitive GABAA receptor, M1-muscarinic, and alpha 2-adrenergic receptors

  7. Suppression of sustained and transient ON signals of amacrine cells by GABA is mediated by different receptor subtypes

    Institute of Scientific and Technical Information of China (English)

    张道启; 杨如; 杨雄里

    1999-01-01

    Intracellular recordings were made from amacrine cells in the isolated, superfused carp retina, and the effects of γ-aminobutyric acid (GABA) on sustained and transient ON signals of these cells were studied. Exogenous GABA application partially suppressed the sustained response of ON amacrine cells, which could be completely reversed by picrotoxin (PTX), a chloride channel blocker, and by bicuculline (BCC), a specific GABA_A receptor antagonist. On the other hand, suppression by GABA of the ON response which was predominantly driven by rod signals in a certain portion of transient ON-OFF amacrine cells was completely blocked by PTX, but not by BCC, indicating that GABA_C receptors may be involved in the effect. These results suggest that GABA_A and GABA_C receptors may be respectively involved in mediating the transmission of sustained and transient signals in the carp inner retina.

  8. Ethanol during adolescence decreased the BDNF levels in the hippocampus in adult male Wistar rats, but did not alter aggressive and anxiety-like behaviors

    Directory of Open Access Journals (Sweden)

    Letícia Scheidt

    2015-09-01

    Full Text Available Objective:To investigate the effects of ethanol exposure in adolescent rats during adulthood by assesssing aggression and anxiety-like behaviors and measuring the levels of inflammatory markers.Methods:Groups of male Wistar rats (mean weight 81.4 g, n = 36 were housed in groups of four until postnatal day (PND 60. From PNDs 30 to 46, rats received one of three treatments: 3 g/kg of ethanol (15% w/v, orally, n = 16, 1.5 g/kg of ethanol (12.5% w/v, PO, n = 12, or water (n = 12 every 48 hours. Animals were assessed for aggressive behavior (resident x intruder test and anxiety-like behaviors (elevated plus maze during adulthood.Results:Animals that received low doses of alcohol showed reduced levels of brain-derived neurotrophic factor (BDNF in the hippocampus as compared to the control group. No significant difference was found in prefrontal cortex.Conclusions:Intermittent exposure to alcohol during adolescence is associated with lower levels of BDNF in the hippocampus, probably due the episodic administration of alcohol, but alcohol use did not alter the level agression toward a male intruder or anxiety-like behaviors during the adult phase.

  9. The heptahelical domain of GABAB2 is activated directly by CGP7930, a positive allosteric modulator of the GABA(B) receptor

    OpenAIRE

    Binet, Virginie; Brajon, Carole; Le Corre, Laurent; Acher, Francine; Pin, Jean-Philippe; Prézeau, Laurent

    2004-01-01

    International audience The gamma-aminobutyric acid, type B (GABA(B)) receptor is well recognized as being composed of two subunits, GABA(B1) and GABA(B2). Both subunits share structural homology with other class-III G-protein-coupled receptors. They are composed of two main domains: a heptahelical domain (HD) typical of all G-protein-coupled receptors and a large extracellular domain (ECD). Although GABA(B1) binds GABA, GABA(B2) is required for GABA(B1) to reach the cell surface. However, ...

  10. 米胚芽発酵ギャバ(GABA)エキス末入りパンの作製

    OpenAIRE

    池脇, 香織; 中村, 雅彦; 石附, 亨; 樋口, 元剛; 小川, 敬之; 山田, 弘幸; 永井, みどり; 小緑, 英行; イケワキ, カオリ; ナカムラ, マサヒコ; イシズキ, トオル; ヒグチ, ゲンゴウ; オガワ, ノリユキ; ヤマダ, ヒロユキ; ナガイ, ミドリ

    2013-01-01

    In this study, in order to promote intake of γ-aminobutyric acid (GABA) routinely and continuously, we prepared several functional breads containing different percentages (0%, 1%, 2% or 3%) of GABA, designated as Taimatsu GABA (T-GABA), produced by fermented rice germ, which has been shown to have various physiological actions. The dough containing T-GABA (1%) showed greater expansion as compared with that containing T-GABA (0%, 2% or 3%). The quantity of wet-type gluten decreased in a T-GABA...

  11. Dioxin exposure reduces the steroidogenic capacity of mouse antral follicles mainly at the level of HSD17B1 without altering atresia

    Energy Technology Data Exchange (ETDEWEB)

    Karman, Bethany N., E-mail: bklement@illinois.edu; Basavarajappa, Mallikarjuna S., E-mail: mbshivapur@gmail.com; Hannon, Patrick, E-mail: phannon2@illinois.edu; Flaws, Jodi A., E-mail: jflaws@illinois.edu

    2012-10-01

    2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a potent ovarian toxicant. Previously, we demonstrated that in vitro TCDD (1 nM) exposure decreases production/secretion of the sex steroid hormones progesterone (P4), androstenedione (A4), testosterone (T), and 17β-estradiol (E2) in mouse antral follicles. The purpose of this study was to determine the mechanism by which TCDD inhibits steroidogenesis. Specifically, we examined the effects of TCDD on the steroidogenic enzymes, atresia, and the aryl hydrocarbon receptor (AHR) protein. TCDD exposure for 48 h increased levels of A4, without changing HSD3B1 protein, HSD17B1 protein, estrone (E1), T or E2 levels. Further, TCDD did not alter atresia ratings compared to vehicle at 48 h. TCDD, however, did down regulate the AHR protein at 48 h. TCDD exposure for 96 h decreased transcript levels for Cyp11a1, Cyp17a1, Hsd17b1, and Cyp19a1, but increased Hsd3b1 transcript. TCDD exposure particularly lowered both Hsd17b1 transcript and HSD17B1 protein. However, TCDD exposure did not affect levels of E1 in the media nor atresia ratings at 96 h. TCDD, however, decreased levels of the proapoptotic factor Bax. Collectively, these data suggest that TCDD exposure causes a major block in the steroidogenic enzyme conversion of A4 to T and E1 to E2 and that it regulates apoptotic pathways, favoring survival over death in antral follicles. Finally, the down‐regulation of the AHR protein in TCDD exposed follicles persisted at 96 h, indicating that the activation and proteasomal degradation of this receptor likely plays a central role in the impaired steroidogenic capacity and altered apoptotic pathway of exposed antral follicles. -- Highlights: ► TCDD disrupts steroidogenic enzymes in mouse antral follicles. ► TCDD particularly affects the HSD17B1 enzyme in mouse antral follicles. ► TCDD does not affect atresia ratings in mouse antral follicles. ► TCDD decreases levels of the proapoptitic factor Bax in mouse antral follicles.

  12. Computational modeling reveals dendritic origins of GABA(A-mediated excitation in CA1 pyramidal neurons.

    Directory of Open Access Journals (Sweden)

    Naomi Lewin

    Full Text Available GABA is the key inhibitory neurotransmitter in the adult central nervous system, but in some circumstances can lead to a paradoxical excitation that has been causally implicated in diverse pathologies from endocrine stress responses to diseases of excitability including neuropathic pain and temporal lobe epilepsy. We undertook a computational modeling approach to determine plausible ionic mechanisms of GABA(A-dependent excitation in isolated post-synaptic CA1 hippocampal neurons because it may constitute a trigger for pathological synchronous epileptiform discharge. In particular, the interplay intracellular chloride accumulation via the GABA(A receptor and extracellular potassium accumulation via the K/Cl co-transporter KCC2 in promoting GABA(A-mediated excitation is complex. Experimentally it is difficult to determine the ionic mechanisms of depolarizing current since potassium transients are challenging to isolate pharmacologically and much GABA signaling occurs in small, difficult to measure, dendritic compartments. To address this problem and determine plausible ionic mechanisms of GABA(A-mediated excitation, we built a detailed biophysically realistic model of the CA1 pyramidal neuron that includes processes critical for ion homeostasis. Our results suggest that in dendritic compartments, but not in the somatic compartments, chloride buildup is sufficient to cause dramatic depolarization of the GABA(A reversal potential and dominating bicarbonate currents that provide a substantial current source to drive whole-cell depolarization. The model simulations predict that extracellular K(+ transients can augment GABA(A-mediated excitation, but not cause it. Our model also suggests the potential for GABA(A-mediated excitation to promote network synchrony depending on interneuron synapse location - excitatory positive-feedback can occur when interneurons synapse onto distal dendritic compartments, while interneurons projecting to the perisomatic

  13. Characterization of GABA/sub A/ receptor-mediated 36chloride uptake in rat brain synaptoneurosomes

    International Nuclear Information System (INIS)

    γ-Aminobutyric acid (GABA) receptor-mediated 36chloride (36Cl-) uptake was measured in synaptoneurosomes from rat brain. GABA and GABA agonists stimulated 36Cl- uptake in a concentration-dependent manner with the following order of potency: Muscimol>GABA>piperidine-4-sulfonic acid (P4S)>4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridin-3-ol (THIP)=3-aminopropanesulfonic acid (3APS)>>taurine. Both P4S and 3APS behaved as partial agonists, while the GABA/sub B/ agonist, baclofen, was ineffective. The response to muscimol was inhibited by bicuculline and picrotoxin in a mixed competitive/non-competitive manner. Other inhibitors of GABA receptor-opened channels or non-neuronal anion channels such as penicillin, picrate, furosemide and disulfonic acid stilbenes also inhibited the response to muscimol. A regional variation in muscimol-stimulated 36Cl- uptake was observed; the largest responses were observed in the cerebral cortex, cerebellum and hippocampus, moderate responses were obtained in the striatum and hypothalamus and the smallest response was observed in the pons-medulla. GABA receptor-mediated 36Cl- uptake was also dependent on the anion present in the media. The muscinol response varied in media containing the following anions: Br->Cl-≥NO3->I-≥SCN->>C3H5OO-≥ClO4->F-, consistent with the relative anion permeability through GABA receptor-gated anion channels and the enhancement of convulsant binding to the GABA receptor-gated Cl- channel. 43 references, 4 figures, 3 tables

  14. Identification and distribution of a GABA receptor mutation conferring dieldrin resistance in the malaria vector Anopheles funestus in Africa.

    Science.gov (United States)

    Wondji, Charles S; Dabire, Roch K; Tukur, Zainab; Irving, Helen; Djouaka, Rousseau; Morgan, John C

    2011-07-01

    Growing problems of pyrethroid resistance in Anopheles funestus have intensified efforts to identify alternative insecticides. Many agrochemicals target the GABA receptors, but cross-resistance from dieldrin resistance may preclude their introduction. Dieldrin resistance was detected in An. funestus populations from West (Burkina Faso) and central (Cameroon) Africa, but populations from East (Uganda) and Southern Africa (Mozambique and Malawi) were fully susceptible to this insecticide. Partial sequencing of the dieldrin target site, the γ-aminobutyric acid (GABA) receptor, identified two amino acid substitutions, A296S and V327I. The A296S mutation has been associated with dieldrin resistance in other species. The V327I mutations was detected in the resistant sample from Burkina Faso and Cameroon and consistently associated with the A296S substitution. The full-length of the An. funestus GABA-receptor gene, amplified by RT-PCR, generated a sequence of 1674 bp encoding 557 amino acid of the protein in An. funestus with 98% similarity to that of Anopheles gambiae. Two diagnostic assays were developed to genotype the A296S mutation (pyrosequencing and PCR-RFLP), and use of these assays revealed high frequency of the resistant allele in Burkina Faso (60%) and Cameroon (82%), moderate level in Benin (16%) while low frequency or absence of the mutation was observed respectively in Uganda (7.5%) or 0% in Malawi and Mozambique. The distribution of the Rdl(R) mutation in An. funestus populations in Africa suggests extensive barriers to gene flow between populations from different regions. PMID:21501685

  15. Homology Modelling of the GABA Transporter and Analysis of Tiagabine Binding

    DEFF Research Database (Denmark)

    Skovstrup, S.; Taboureau, Olivier; Bräuner-Osborne, H.;

    2