GABA-gated chloride ion influx and receptor binding studies in C57BL6J and DBA2J mice

GABA-gated chloride ion influx was measured in brain 'microsac' preparations of young (20-22-day-old) and older (40-42-day-old) C57BL6J and DBA2J mice. The young DBA2J mice are susceptible to audiogenic seizures. GABA sensitivity was reduced in young DBA2J mice as compared to age-matched C57BL6J mice or older mice of either strain. Age and strain differences in ligand binding to GABA/benzodiazepine receptor complex and glutamate receptor could not account for this finding. These results provide evidence for a defect in GABA-gated chloride ion influx in audiogenic seizure-susceptible DBA2J mice.