The cholinergic nuclei of the basal forebrain of the hamster (Mesocricetus auratus): a combined Golgi- and AChE-topochemical investigation.

The cholinergic basal forebrain nuclear complex of the golden hamster was investigated Golgi-architectonically and AChE-topochemically using enzymehistochemical and immunohistochemical methods. We demonstrated 12 different classes of neurons in the whole basal forebrain complex with the Golgi-Kopsch-technique. The classical anatomical subdivision of the septal-region into nucleus medialis septi and nucleus tractus diagonalis has not been confirmed by results elaborated with this method. We found at least one class of neurons with varicose dendrites in every part of the cholinergic basal forebrain complex. The varicosities reacted positively for AChE. This morphological feature might be characteristic for cholinergic neurons in the nuclei of the basal forebrain complex.