Objective: Isoflurane is widely used for inhaled general anesthesia. However, the mechanisms of isoflurane-induced cardiovascular depression are not fully understood. The effect of isoflurane on GABAA receptor expression in the NTS may underlie cardiovascular depression. Methods: The blood pressure (BP) and heart rates (HR) of conscious rats were confirmed initially using a CODA non-invasive bl...

Attenuated behavioral sensitivity to neurosteroids has been reported for mice deficient in the GABAA receptor subunit. We therefore investigated potential subunit-specific neurosteroid pharmacology of the following GABAA receptor isoforms in a transient expression system: 1 3 2L, 1 3 , 6 3 2L, and 6 3 . Potentiation of submaximal GABAA receptor currents by the neurosteroid tetrahydrodeoxycortic...

Benzodiazepine (BZ) binding site ligands are important central nervous system (CNS) drugs. Their numbers and our knowledge of how they interact with the BZ-binding site of GABAA receptors are both rapidly expanding. The GABAA receptor is a member of the ligand-gated ion channel superfamily. In general, it consists of an assembly of transmembrane pentamers of different subunit compositions (1). ...

Understanding the effects of tobacco smoking on neuroadaptations in GABAA receptor levels over alcohol withdrawal will provide critical insights for the treatment of comorbid alcohol and nicotine dependence. We conducted parallel studies in human subjects and nonhuman primates to investigate the differential effects of tobacco smoking and nicotine on changes in GABAA receptor availability durin...

There are coflicting reports regarding the role of GABA in morphine analgesia. While-sorne investigators have reported that treatment with GABAA receptor agonist muscimol and GABA transaminase inhibitors potentiates morphine analgesia (2.4.6) others have reported antagonism of morphine analgesia (8.10). In view of these conflicting reports and since the analgesic profile 'of THIP, a GABAA recep...

introduction: the bed nucleus stria terminalis (bst) is a part of the limbic system. it was recently shown that chemical stimulation of the bst by l-glutamate elicited cardiovascular depressive responses. in the present study, we have investigated the possible cardiovascular role of the gabaergic receptors in bst by microinjection of its agonist and antagonists. methods: experiments were perfor...

GABAA receptors mediate fast inhibitory neurotransmission in the brain. Dysfunction of these receptors is associated with various psychiatric/neurological disorders and drugs targeting this receptor are widely used therapeutic agents. Both the efficacy and plasticity of GABAA receptor-mediated neurotransmission depends on the number of surface GABAA receptors. An understudied aspect of receptor...

Temporal lobe epilepsy (TLE) associated with hippocampal sclerosis (HS) is a form of focal epilepsy, which is particularly resistant to medical treatment. It is, however, established that patients with TLE and HS respond favorably to surgery. Accumulating evidence indicates that TLE is associated with impairment in synaptic signaling via GABA (γ-aminobutyric acid), the main inhibitory neurotran...

The effects of a single convulsive dose of pentylenetetrazol (PTZ, 45 mg/kg i.p.) on rat brain gamma-aminobutyric acid type A (GABAA) receptors were studied. Selected GABAA receptor subunit mRNAs were measured by Northern blot analysis (with beta-actin mRNA as a standard). Four hours after PTZ, the GABAA receptor gamma2-mRNA was decreased in hippocampus, cerebral cortex, and cerebellum; alpha1-...

GABA receptors of bipolar cells from the skate retina: actions of zinc on GABA-mediated membrane currents. J. Neurophysiol. 78: 2402-2412, 1997. gamma-Aminobutyric acid (GABA)-induced currents were recorded from isolated bipolar cells of the skate retina using perforated patch-clamp methodology. Pharmacological analysis of the responses, using selective agonists and antagonists of the major cla...