Choline acetyltransferase-containing neurons in rodent brain demonstrated by immunohistochemistry.

Choline acetyltransferase was demonstrated in neuronal structures of the rodent central nervous system by immunohistochemistry through the application of Fab fragments obtained from monospecific antiserums to human choline acetyltransferase. The specificity of the antiserum for the enzyme was confirmed by the staining of both the ventral horn motor neurons in the rat spinal cord and the neuromuscular junction of the guinea pig diaphragm. Enzyme-containing cell bodies were observed in frontal sections of rat and guinea pig brain in the neostriatum, accumbens, nucleus of the diagonal band, medial septum, and olfactory tubercle. Positively staining fibers and probable nerve terminals were also found in the olfactory tubercle field and other areas of the basal forebrain. The results provide information on the distribution of the cholinergic systems in the rostral forebrain of the rodent.