tyrosine hydroxylase immunohistochemical examination of the mesencephalon of severely parkinsonian mptp-treated macaque fascicularis monkeys revealed a marked loss of substantia nigra pars compacta ( snc ) neurons in both medial and central portions of the nucleus with a relative sparing of neurons in the dorsal-most portions of the substantia nigra .
C0175412
substantia nigra pars compacta
C0038590
substantia nigra