Pharmacology of methyl- and propyl-beta-carbolines in a hereditary model of epilepsy.

Intravenous administration of beta-carboline-3-carboxylate methyl ester (beta-CCM) produced convulsions at small doses (0.03 mg/kg) in adult chickens, homozygous for the epileptic gene. Nonepileptic heterozygote hatchmates (carriers) did not undergo seizures at doses of 1 mg/kg, and doses of 3-5 mg/kg produced only brief myoclonic responses. The convulsant effect of beta-CCM could be prevented by pretreatment with large doses of beta-carboline-3-carboxylate propyl ester (beta-CCP). beta-Carboline-3-carboxylate methyl ester displayed a higher affinity than diazepam in displacement studies on synaptosomal membrane preparations from brains of epileptic and carrier chickens.