Inhibition at bipolar cell axon terminals regulates excitatory signaling to ganglion cells and is mediated, in part, by GABAC receptors. We investigated GABAC receptor-mediated inhibition using pharmacological approaches and genetically altered mice that lack GABAC receptors. Responses to applied GABA showed distinct time courses in various bipolar cell classes, attributable to different propor...

The ρ1 GABAC receptor is a ligand-gated chloride ion channel that shows promise as a therapeutic target for myopia, sleep disorders, memory and learning facilitation, and anxiety-related disorders. As such, there is a need for molecular probes to understand the role GABAC receptors play in physiological and pathological processes. To date, no labeled (either radioactive or fluorescent) GABAC se...

Resveratrol is a phytoalexin found in grapes, red wine, and berries. Resveratrol has been known to have many beneficial health effects, such as anti-cancer, neuroprotective, anti-inflammatory, and life-prolonging effects. However, relatively little is known about the effects of resveratrol on the regulation of ligand-gated ion channels. We have previously reported that resveratrol regulates sub...

Our previous studies showed that gamma-aminobutyric acid (GABA)A and GABAB receptors are involved in rat sperm acrosome reaction induced by progesterone or GABA. Here, we report the presence of GABAC receptor in rat testis and spermatozoa. Full-length complementary DNA encoding the rho1, rho2 and rho3 subunits of GABAC receptor were cloned from rat testis; their sequences are identical to those...

GABAC receptors (GABACRs) are widely expressed in the mammalian subcortical visual system, particularly in the retina and superior colliculus (SC). GABACRs are composed of specific ρ1-3 subunits whose expression varies among visual structures. Thus, ρ1 subunits are most abundant in retina and their loss eliminates GABACR expression and function (McCall et al. J Neurosci 22:4163-4174). In the SC...

-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...

In the central nervous system inhibitory neurotransmission is primarily achieved through activation of receptors for gamma-aminobutyric acid (GABA). Three types of GABA receptors have been identified on the basis of their pharmacology and electrophysiology. The predominant type, termed GABAA and a recently identified type, GABAC, have integral chloride channels, whereas GABAB receptors couple t...

The quantitative structure–activity relationship (QSAR) model constructed in this work represents the first quantitative investigation into agonist binding at GABAC receptors. This model is based upon the three-dimensional structures of (g-aminobutyric acid (GABA) and 12 other biologically active GABA analogues. These structures are obtained by geometry optimization and conformational explorati...

Presynaptic inhibition onto axons regulates neuronal output, but how such inhibitory synapses develop and are maintained in vivo remains unclear. Axon terminals of glutamatergic retinal rod bipolar cells (RBCs) receive GABAA and GABAC receptor-mediated synaptic inhibition. We found that perturbing GABAergic or glutamatergic neurotransmission does not prevent GABAergic synaptogenesis onto RBC ax...

Whole cell currents were recorded from rod and cone bipolar cells in a slice preparation of the rat retina. Use of the gramicidin D perforated-patch technique prevented loss of intracellular compounds. The recorded cells were identified morphologically by injection with Lucifer yellow. During the recordings, the cells were isolated synaptically by extracellular cobalt. To distinguish the gamma-...