CHOLINERGIC NEURONS CONTAIN CALBINDIN-D28K IN THE MONKEY MEDIAL SEPTAL NUCLEUS AND NUCLEUS OF THE DIAGONAL BAND - AN IMMUNOCYTOCHEMICAL STUDY

The distribution patterns of choline acetyltransferase (CAT), as a mar ker for cholinergic neurons, and Calbindin-D28k (CaBP) immunoreactivit ies in the forebrain basal ganglia of the Japanese monkey Macaca fusca ta were compared. Similar distribution patterns of CAT and CaBP immuno reactivities were found in the medial septal nucleus (MS) and the nucl eus of the diagonal band of Broca (DBB). Double-labeling fluorescence immunocytochemistry revealed that most, but not all, cholinergic neuro ns were CaBP-immunoreactive in the MS and DBB. The results suggest tha t CaBP may play a role in the septohippocampal cholinergic neuron syst em of the monkey.