Regional GABA-stimulated chloride uptake in amygdala kindled rats

γ-Aminobutyric acid (GABA)-stimulated 36chloride (Cl −) influx into membrane vesicles derived from cerebral cortex, hippocampus, cerebellum and midbrain/brainstem was evaluated in naive rats and amygdala or sham kindled rats. GABA-stimulated 36Cl − uptake was greatest in cortex and hippocampus of naive rats. One week after amygdala kindling, 10 μM GABA-stimulated 36Cl − influx was significantly reduced in each brain region, except midbrain/brainstem, indicating a regional variation in impaired GABAergic function. Midazolam potentiation of GABA-mediated Cl − flux showed a regional variation. The effect of midazolam in kindled rats indicated either an increase in efficiency of GABA/benzodiazepine coupling in areas of reduced GABA function or its ability to restore Cl − channel function to the pre-kindled state.