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Benzodiazepine Receptors (benzodiazepine + receptor)
Terms modified by Benzodiazepine Receptors Selected AbstractsQuantitative Structure,Activity Relationship Studies for the Binding Affinities of Imidazobenzodiazepines for the ,6 Benzodiazepine Receptor Isoform Utilizing Optimized Blockwise Variable Combination by Particle Swarm Optimization for Partial Least Squares ModelingMOLECULAR INFORMATICS, Issue 1 2007Leqian Hu Abstract Binding affinities of a series of substituted imidazobenzodiazepines for the ,6 Benzodiazepine Receptor (BzR) isoform are investigated by the Optimized Blockwise Variable Combination (OBVC) by Particle Swarm Optimization (PSO) based on Partial Least Squares (PLS) modeling. The QSAR analysis result showed that MolRef, AlogP, MRCM**-3, Rotatable bonds (Rotlbonds), Hydrogen Bond Acceptors (Hbond acceptor), five Jurs descriptors, two Shadow indices descriptors and principal moment of inertia are the most important descriptors among all the investigated descriptors. One can change the molar refractivity, the polar interactions between molecules, the shape of the molecules, the principal moments of inertia about the principal axes of a molecule, the hydrophobic character of the molecule, the number of Rotlbonds and Hbond acceptors of the compounds to adjust the binding affinities of imidazobenzodiazepine for the ,6 BzR isoform. The Quantitative Structure,Activity Relationship (QSAR) analysis result was also compared with MLR, PLS, and hierarchical PLS algorithms. It has been demonstrated that OBVC by PSO for PLS modeling shows satisfactory performance in the QSAR analysis. [source] Central and Peripheral Benzodiazepine ReceptorsEPILEPSIA, Issue 2 2006Tracy Butler No abstract is available for this article. [source] ChemInform Abstract: Synthesis and Structure of 3-Arylidene and 3-Hetarylidene-1,2-dihydro-3H-1,4-benzodiazepin-2-ones and Their Affinity Toward CNS Benzodiazepine Receptors.CHEMINFORM, Issue 16 2008V. I. Pavlovsky Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Interaction of Novel Condensed Triazine Derivatives with Central and Peripheral Type Benzodiazepine Receptors: Synthesis, in vitro Pharmacology and Modelling.CHEMINFORM, Issue 38 2006Eva Szarics Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] The correlation between cerebral glucose metabolism and benzodiazepine receptor density in the acute vegetative stateEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2002J. Rudolf This paper compares the results of parallel positron emission tomography (PET) studies of regional cerebral glucose metabolism with the radiotracer 18F-fluorodeoxyglucose (FDG) and benzodiazepine receptor (BZR) density by PET using the BZR ligand 11C-flumazenil (FMZ), a tracer of neuronal integrity, in nine patients with acute vegetative state (AVS, duration <1 month). Overall glucose utilization was significantly reduced in AVS in comparison with age-matched controls (global metabolic rate for glucose 26 ,mol/100 g/min in AVS vs. 31 ,mol/100 g/min in controls). FMZ-PET demonstrated a considerable reduction of BZR binding sites in all cortical regions that grossly corresponded to the extent of reduction of cerebral glucose metabolism assessed with FDG-PET, whilst the cerebellum was spared from neuronal loss. In controls, cortical relative flumazenil binding was not lower than five times the average white matter activity, whilst in AVS, nearly all values were below this threshold. There was no relevant overlap of the data of relative flumazenil binding between both groups. The comparison of FDG- and FMZ-PET findings in AVS demonstrates that alterations of cerebral glucose consumption do not represent mere functional inactivation, but irreversible structural brain damage. [source] The development of PET radioligands for imaging the translocator protein (18,kDa): What have we learned?JOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 7 2010Christopher Luus Abstract The translocator protein (TSPO; 18,kDa), formerly known as the peripheral benzodiazepine receptor (PBR), is minimally expressed in the healthy brain. On the other hand, increased levels of TSPO have been noted in brain disorders for which an immune response is elicited. This increase in TSPO expression has been reported to coincide with the process of microglial activation making the measurement of TSPO density a useful indicator of active brain disease. To this end several new classes of TSPO positron emission tomography radioligands have been developed and evaluated. However, the incomplete pharmacological characterization of the TSPO and its ligands as well as differences in pathophysiology, pharmacology and molecular nature across species and tissue types means that caution must be exercised when comparing data obtained with various TSPO radioligands. A re-evaluation of our interpretation of imaging data, which better correlates with our current understanding of TSPO pharmacology in disease, requires consideration. Copyright © 2010 John Wiley & Sons, Ltd. [source] Peripheral-type benzodiazepine receptor (PBR) in association with stress and brain agingPSYCHOGERIATRICS, Issue 4 2006Mitsunobu YOSHII No abstract is available for this article. [source] Neuroradiologic Findings in Focal Cortical Dysplasia: Histologic Correlation with Surgically Resected SpecimensEPILEPSIA, Issue 2001Kazumi Matsuda Summary: ,Purpose: We investigated the neuroradiologic characteristics of focal findings of surgically resected specimens obtained from 47 patients with focal cortical dysplasia (FCD). Methods: Forty cases were detected by magnetic resonance imaging (MRI), and two cases were detected only by single-photon emission computed tomography (SPECT), but five cases could not be detected before operation. Results: MRI revealed abnormal gyri and sulci in 34 patients (pachygyric in 18, polymicrogyric in 10, both in six), and blurring of the gray matter,white matter junction in 29 (72%) patients. Signal abnormalities were found in 36 (90%) patients, in the gray matter in 32, with white matter in 30, and at the gray matter,white matter junction in 13. Moreover, peculiar patterns of abnormal signals in the white matter were recognized, including remarkably abnormal subcortical signals of T2 hyperintensity and T1 hypointensity adjacent to the dysplastic cortex in 15 cases, high radiated T2 signals extending from the ependymal surface of the lateral ventricle to the overlying cortex in 11 cases, and widespread abnormal signals in the white matter with gray matter involvement in four cases. Histologically, these abnormal signals corresponded to various degrees of dyslamination and morphologic abnormalities of neurons and glial cells in the gray matter, and to dysmyelination, ectopic clustering of dysplastic neurons, glial proliferation, and necrotic change in the white matter. Regional cerebral blood flow SPECT showed interictal hypoperfusion in 29 (62%) of the 47 patients, interictal hyperperfusion in two, and ictal hyperperfusion in 28 of the 34 patients associated with FCD. [123I]iomazenil SPECT demonstrating the distribution of central benzodiazepine receptors showed low accumulations localized spatially corresponding to the epileptogenic foci associated with FCD in seven of eight patients. Conclusions: These results demonstrate that neuroimaging reflects various structural and functional changes closely related to epileptogenesis in FCD. [source] Effects of central and systemic injections of peripheral benzodiazepine receptor ligands on the anxiolytic actions of ethanol in ratsADDICTION BIOLOGY, Issue 2 2001G. S. Morato The influence of peripheral benzodiazepine receptor ligands Ro5-4864 (0.05 or 1.0 mg/kg, i.p.) or PK11195 (0.05 or 1.0 mg/kg, i.p.) on the anxiolytic effect of ethanol (1.2 g/kg; 14% p/v; i.p.) was investigated in rats tested on the elevated plus-maze. Other animals were injected through intrahippocampal administrations of the ligands (0.5 or 1.0 nmol/0.5 ,l) before ethanol (1.2g/kg; 14% p/v; i.p.) and submitted to the elevated plus-maze test. The results showed that the systemic administration of either ligands 24 hours before the ethanol treatment resulted in a reduced anxiolytic effect of this drug. Only PK11195 reversed the effect of ethanol after intrahippocampal injection. These data suggest that peripheral benzodiazepine receptors play a role in ethanol anxiolysis. [source] Relations between open-field, elevated plus-maze, and emergence tests in C57BL/6J and BALB/c mice injected with GABA- and 5HT-anxiolytic agentsFUNDAMENTAL & CLINICAL PHARMACOLOGY, Issue 3 2010Robert Lalonde Abstract Two 5HT1A receptor agonists and chlordiazepoxide were examined in open-field, elevated plus maze, and emergence tests. At doses with no effect in the open-field, chlordiazepoxide increased open and open/total arm visits as well as open arm duration in the elevated plus maze, whereas 5HT1A receptor agonists showed an anxiolytic response on a single measure. The anxiolytic action of chlordiazepoxide was limited to the less active BALB/c strain. Unlike the 5HT1A receptor agonists, chlordiazepoxide was also anxiolytic in the emergence test, once again only in BALB/c and not C57BL/6J mice. Significant correlations were found between emergence latencies and specific indicators of anxiety in the elevated plus-maze in chlordiazepoxide-treated but not in mice treated with buspirone and 8-OH-DPAT. These results indicate that elevated plus-maze and emergence tests depend on benzodiazepine receptors. In contrast, 5HT1A receptor agonists were ineffective in the emergence test and no correlation was found between emergence latencies and specific indicators of anxiety in the elevated plus-maze. Though superficially similar, the emergence test seems to tap into a partially separate facet of anxiety. [source] The triakontatetraneuropeptide TTN increases [Ca2+]i in rat astrocytes through activation of peripheral-type benzodiazepine receptorsGLIA, Issue 2 2001Pierrick Gandolfo Abstract Astrocytes synthesize a series of regulatory peptides called endozepines, which act as endogenous ligands of benzodiazepine receptors. We have recently shown that one of these endozepines, the triakontatetraneuropeptide TTN, stimulates DNA synthesis in astroglial cells. The purpose of the present study was to determine the mechanism of action of TTN on cultured rat astrocytes. Binding of the peripheral-type benzodiazepine receptor ligand [3H]Ro5-4864 to intact astrocytes was displaced by TTN, whereas its C-terminal fragment (TTN[17,34], the octadecaneuropeptide ODN) did not compete for [3H]Ro5-4864 binding. Microfluorimetric measurement of cytosolic calcium concentrations ([Ca2+]i) with the fluorescent probe indo-1 showed that TTN (10,10 to 10,6 M) provokes a concentration-dependent increase in [Ca2+]i in cultured astrocytes. Simultaneous administration of TTN (10,8 M) and Ro5-4864 (10,5 M) induced an increase in [Ca2+]i similar to that obtained with Ro5-4864 alone. In contrast, the effects of TTN (10,8 M) and ODN (10,8 M) on [Ca2+]i were strictly additive. Chelation of extracellular Ca2+ by EGTA (6 mM) or blockage of Ca2+ channels with Ni2+ (2 mM) abrogated the stimulatory effect of TTN. The calcium influx evoked by TTN (10,7 M) or by Ro5-4864 (10,5 M) was not affected by the N- and T-type calcium channel blockers ,-conotoxin (10,6 M) and mibefradil (10,6 M), but was significantly reduced by the L-type calcium channel blocker nifedipine (10,7 M). Patch-clamp studies showed that, at negative potentials, TTN (10,7 M) induced a sustained depolarization. Reduction of the chloride concentration in the extracellular solution shifted the reversal potential from 0 mV to a positive potential. These data show that TTN, acting through peripheral-type benzodiazepine receptors, provokes chloride efflux, which in turn induces calcium influx via L-type calcium channels in rat astrocytes. GLIA 35:90,100, 2001. © 2001 Wiley-Liss, Inc. [source] The anxiolytic effect of Sho-ju-sen, a Japanese herbal medicine, assessed by an elevated plus-maze test in micePHYTOTHERAPY RESEARCH, Issue 2 2001Hisashi Kuribara Abstract Sho-ju-sen (SK), a Japanese herbal medicine with a nourishing tonic action, is composed of a water extract of Kumazasa leaves (Sasa kurinensis Makino et Sibata) (SS), and ethanol extracts of Japanese red pine needles (Pinus densiflora Sieb. et Zucc) (PN) and Ginseng roots (Panax ginseng C. A. Meyer) (PX) in the ratio 8:1:1. In this study, an elevated plus-maze test in mice was carried out to assess whether SK had an anxiolytic effect. No significant change was observed in either the plus-maze or activity test following a single administration of SK (10 and 20,mL/kg p.o.). However, mice allowed a free intake of SK (10% solution) for 5 days and longer showed a significant prolongation of the time spent in the open arms (an anxiolytic effect), as long as that caused by the benzodiazepine anxiolytic diazepam (1,mg/kg p.o.). SK (1%, 3% and 30% solutions for 7 days) tended to develop the anxiolytic effect. Of the constituents of SK, SS (8% solution), but not PN (1% solution) or PX (1% solution), resulted in the anxiolytic effect. Except for a slight acceleration in the motor activity by PN (1% solution), no significant change in the motor activity was produced by any treatment with SK, SS or PX. The combined treatment of SK (10% solution) or SS (8% solution) with 1,mg/kg diazepam enhanced the anxiolytic effect. Flumazenil (0.1,mg/kg s.c.), a benzodiazepine receptor antagonist, alone did not change the time spent in the open arms. However, it completely reversed the anxiolytic effect of SK, SS and diazepam. The present results suggest that: (1) long-term treatment with SK develops an anxiolytic effect, (2) SS is the main constituent for the anxiolytic effect of SK, and (3) benzodiazepine receptors are involved in the anxiolytic effect of SK and SS. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||||||||