[Interactions of GABA and Cl ionophore-binding subunits of GABA-benzodiazepine receptor complex in the brain of inbred mice].

The displacement curves of the effect of GABA on the S35-tert-butyl bicyclophosphorothionate binding to the brain membranes of inbred mice were analysed. It was revealed the lack of marked interstrain differences in dependent on the ionic force of incubation medium modification of IC50. After incomplete stimulation of Cl(-)-ionophore subunit (50 mM NaCl) reliable interstrain differences in the value of nHill were shown. Bicuculline in the same conditions prevented the inhibitory effect of GABA (10(-5) M). But submaximal concentrations of bicuculline (5 X 10(-6) M, 10(-6) M) stimulated the radioligand binding in the presence of GABA (10(-6) M). It was marked more expressed bicuculline stimulation effect on the membranes of C57Bl/6 mice, as compared to BALB/c mice.