Specific binding of 36Cl- ions to rat cerebellar membranes: effect of GABA and S-100 protein.
36Cl- ions display specific binding to rat cerebellum membranes. Although this binding at a 136Cl-1 of 2 X 10(-7) M is only 18% of total binding, it shows several interesting characteristics. It is higher in a GABA receptor rich region such as the cerebellum than in the cerebral cortex. It is higher in synaptic than in total membranes of the cerebral cortex. 36Cl- binding to cerebellar membranes in inhibited by 10(-4) M picrotoxin and by 10(-4) M GABA, the GABA effect being antagonized by bicuculline. All these characteristics appear to point out that 36Cl- specifically binds to GABAA receptor associated Cl- channels in their closed state. The brain specific antigen S-100 also is able to inhibit 36Cl- binding to rat cerebellar membranes.
D000818:Animals; D001640:Bicuculline / Q000494:pharmacology; D002531:Cerebellum / Q000378:metabolism*; D002540:Cerebral Cortex / Q000378:metabolism*; D002712:Chlorides / Q000378:metabolism*; D008297:Male; D008566:Membranes / Q000378:metabolism; D010852:Picrotoxin / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D009418:S100 Proteins / Q000494:pharmacology*; D013570:Synaptic Membranes / Q000378:metabolism; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D001640:Bicuculline; D002712:Chlorides; D010852:Picrotoxin; D009418:S100 Proteins; D005680:gamma-Aminobutyric Acid