The actions of ethanol on gamma-aminobutyric acid-A (GABAA) receptor-mediated synaptic transmission in rat hippocampal CA1 neurons remain controversial. Recent studies have reported that intoxicating concentrations of ethanol (10-100 mM) can potentiate, inhibit, or have no effect on GABAA receptor-mediated synaptic responses in this brain region. The essential determinants of ethanol sensitivit...

Synaptically evoked transmembrane movements of Ca2+ in the adult CNS have almost exclusively been attributed to activation of glutamate receptor channels and the consequent triggering of voltage-gated calcium channels (VGCCs). Using microelectrodes for measuring free extracellular Ca2+ ([Ca2+]o) and extracellular space (ECS) volume, we show here for the first time that synaptic stimulation of g...

Structural analogues of ZAPA, Z-3-[(aminoiminomethyl)thio]prop-2-enoic acid, an isothiouronium analogue of GABA, are potent GABAA agonists as seen in the isolated guinea-pig ileum and in the facilitation of [3H]diazepam binding to rat brain membranes. Compounds with guanidino or amidine groups replacing the amino functionality of GABA were also found to be active. The highest activity was displ...

Family, twin, and adoption studies have demonstrated that genes play an important role in the development of alcoholism. We investigated the association between alcoholism and the genetic polymorphisms of the GABAA receptor genes on chromosome 5q33-34 in Korean population. The genotype of the GABAA receptor gene polymorphisms were determined by performing polymerase chain reaction genotyping fo...

Quercitrin is a well-known flavonoid that is contained in Flos Albiziae, which has been used for the treatment of anxiety. The present study investigated the anxiolytic-like effects of quercitrin in experimental models of anxiety. Compared with the control group, repeated treatment with quercitrin (5.0 and 10.0 mg/kg/day, p.o.) for seven days significantly increased the percentage of entries in...

Over the last several years, evidence has accumulated that the GABAA receptor is compromised in animal models for fragile X syndrome (FXS), a common hereditary form of intellectual disability. In mouse and fly models, agonists of the GABAA receptor were able to rescue specific consequences of the fragile X mutation. Here, we imaged and quantified GABAA receptors in vivo in brain of fragile X pa...

The central nervous system (CNS) depressant and anticonvulsant activities of Citrus limon (L.) Osbeck, Rutaceae, essential oil (EO) were investigated in animal models. The EO (50, 100 and 150 mg/kg) injected by oral route (p.o.) in mice caused a significant decrease in the motor activity of animals when compared with the control group, up to thirty days after the administration and the dose of ...

PURPOSE The inhibition of phosphodiesterase 5 produces an antinociception through the increase of cyclic guanosine monophosphate (cGMP), and increasing cGMP levels enhance the release of gamma-aminobutyric acid (GABA). Furthermore, this phosphodiesterase 5 plays a pivotal role in the regulation of the vasodilatation associated to cGMP. In this work, we examined the contribution of GABA receptor...

-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian brain. The GABA receptor type C (GABAC) is a ligand-gated ion channel with pharmacological properties distinct from the GABAA receptor. To date, only three binding domains in the recombinant 1 GABAC receptor have been recognized among six potential regions. In this report, using the substituted cysteine accessib...

The median raphe nucleus (MR) has been shown to exert a powerful influence on behavioral arousal and marked locomotor hyperactivity can be produced by intra-MR injections of a variety of drugs including GABAA and GABAB agonists, excitatory amino acid antagonists, and μ- and δ-opioid agonists. Other studies have indicated that the MR exerts an inhibitory influence on ascending dopamine systems, ...