Anticonvulsant action of 2-amino-7-phosphonoheptanoic acid in the substantia nigra.

Focal injection of 2-amino-7-phosphonoheptanoic acid in the substantia nigra, pars reticulata or pars compacta, in rats produces a dose-dependent suppression of the tonic extensor seizure component in the electroshock test. Haloperidol pretreatment prevents stereotyped behaviour induced by 2-amino-7-phosphonoheptanoic acid, but does not change the effect on the electroshock test. This anticonvulsant effect of 2-amino-7-phosphonoheptanoic acid probably results from an antagonist action at a receptor site sensitive to N-methyl-D-aspartate leading to a decrease in activity in nigral efferent systems.