MPTP-induced ventral mesencephalic cell loss in the cat.

Immunohistochemical analysis of tyrosine hydroxylase (TH)-containing neurons in the cat ventral mesencephalon revealed a marked loss of substantia nigra pars compacta neurons and moderate losses of TH-positive neurons in the ventral tegmental area, retrorubral or A8 region, and in the substantia nigra pars lateralis of cats treated with the neurotoxin N-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). The pattern and magnitude of cell loss in these ventral mesencephalic regions parallels that previously reported for the MPTP-treated monkey. These results further support the use of the cat as a model for studying the pathology to catecholaminergic neurons induced by MPTP.