Cholinergic-GABAergic synaptic interconnections in the rat amygdaloid complex: an electron microscopic double immunostaining study.

A correlated light and electron microscopic immunocytochemical study was performed to analyze 1) the distribution of cholinergic and GABAergic perikarya and terminals in the rat amygdala, and 2) the cholinergic innervation of GABAergic neurons in some amygdaloid nuclei. We will demonstrate here that cholinergic terminals establish synaptic contacts with GABAergic neurons in the basolateral amygdaloid region. These GABAergic neurons in turn are supposed to exert an inhibitory influence on the centromedial amygdaloid region. Our data suggest that the amygdaloid nuclei provide a useful model for studies of cholinergic-GABAergic synaptic interconnections in the CNS.