Bicuculline GABAa receptor binding

Experimentally all GABA antagonists induce convulsions. These include the genuine receptor antagonist bicuculline, which competes with GABA for its recognition site on the GABAa receptor and picrotoxin, which binds to a different site more closely related to the chloride ion channel. 

Watt 62), one of the earlier researchers to recognize the potential of African plants in improving mental health, reported the use of Cotyledon orbiculata (Crassulaceae) leaves to treat epilepsy. Again, in vivo studies have demonstrated both aqueous and methanol extracts of C. orbiculata have anticonvulsant properties (moderate protection against pentylenetetrazole, bicuculline, picrotoxin and A-methyl-dl-aspartic induced seizures in mice) 63). However, the ethanolic extract did not show in vitro GABAA-benzodiazepine receptor binding activity 64). 

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