Colocalization of enkephalin-like and choline acetyltransferase-like immunoreactivities in olivocochlear neurons of the guinea pig.

Abstract
The guinea pig lateral superior olive was examined immunocytochemically using antisera against enkephalin and choline acetyltransferase sequentially on the same sections. A colocalization of choline acetyltransferase-like and enkephalin-like immunoreactivities was found in cells of the lateral superior olive that give rise to the lateral system of olivocochlear efferents. Only choline acetyltransferase-like immunoreactivity was observed in the group of olivary nuclei that give rise to the medial group of olivocochlear fibers.