This study addresses how gamma-aminobutyric acid-A(GABAA) and GABAC receptors confer distinct temporal properties to neuronal synaptic responses. The retina is a model system for the study of postsynaptic contributions to synaptic responses because GABAergic amacrine cells synapse onto neurons, which have different combinations of GABAA and GABAC receptors. It is not known, however, how GABAA v...

The GABAA receptors are the major inhibitory receptors in the brain and are localized at both synaptic and extrasynaptic membranes. Synaptic GABAA receptors mediate phasic inhibition, whereas extrasynaptic GABAA receptors mediate tonic inhibition. Both phasic and tonic inhibitions regulate neuronal activity, but whether they regulate each other is not very clear. Here, we investigated the funct...

In the postnatal subventricular zone (SVZ) local cues or signaling molecules released from neuroblasts limit the proliferation of glial fibrillary acidic protein (GFAP)-expressing progenitors thought to be stem cells. However, signals between SVZ cells have not been identified. We show that depolarizations of neuroblasts induce nonsynaptic SNARE-independent GABAA receptor currents in GFAP-expre...

20 We previously reported that gastric activity is controlled by a robust GABAA 21 receptor–mediated inhibition in the medial nucleus of the tractus solitarius (mNTS) 22 (Herman et al. 2009) and that μ-opioid receptor activation inhibits gastric tone by 23 suppression of this GABA signaling (Herman et al. 2010). These data raised two 24 questions: (1) whether any of this inhibition was due to t...

Many neurons express a multiplicity of GABAA receptor subunit isoforms. Despite having only a single source of inhibitory input, the cerebellar granule cell displays, at various stages of development, more than 10 different GABAA subunit types. This subunit diversity would be expected to result in significant receptor heterogeneity, yet the functional consequences of such heterogeneity remain p...

γ-Hydroxybutyric acid (GHB) is an endogenous compound and a drug used clinically to treat the symptoms of narcolepsy. GHB is known to be an agonist of GABAB receptors with millimolar affinity, but also binds with much higher affinity to another site, known as the GHB receptor. While a body of evidence has shown that GHB does not bind to GABAA receptors widely, recent evidence has suggested that...

Using whole cell patch-clamp recording in a rat brain stem slice preparation, we found that gamma-aminobutyric acid (GABA) and glycine act as cotransmitters to hypoglossal motoneurons (HMs). Focal application of GABA and glycine onto a single HM revealed that GABAA and glycine receptors are present on the same neuron. To demonstrate that HMs receive both GABAergic and glycinergic synaptic input...

Impaired transmission in GABAergic circuits is thought to contribute to the pathogenesis of epilepsy. Although it is well established that major reorganization of GABAA receptor subtypes occurs in the hippocampus of patients with medically refractory temporal lobe epilepsy (TLE), it is unclear whether this disorder is also associated with alterations in GABAA receptor subtypes in the neocortex....

Monoclonal antibodies (mAbs) and conventional antisera were raised to the affinity-purified GABAA receptor/benzodiazepine receptor/Cl- channel complex. The antibodies immunoprecipitated the affinity-purified complex in Triton X-100 and also reacted with the complex in a solid-phase radioimmunoassay. Immunoblots indicated that the mAb 62-3G1 reacted with the 57,000 Mr peptide subunit of the affi...

GABAA receptor activation augments stimulated release of 3H-norepinephrine (NE) in brain slices from female rats. This effect is not blocked by acetazolamide or MK-801, indicating that permeability of the GABAA chloride channel to bicarbonate ions and NMDA receptor activation do not mediate GABA-induced NE release. Furthermore, GABA augments 3H-NE release from slices, but not from isolated nerv...