L-DOPA immunoreactive neurons in the ventrolateral area of arcuate nucleus of the house-shrew (Suncus murinus)

L-DOPA immunoreactivity was demonstrated in neurons of the house-shrew brain, using an immunocytochemical method in conjunction with a specific anti-L-DOPA serum. The neurons in the ventrolateral area of arcuate nuclei were tyrosine hydroxylase- and L-DOPA-immunoreactive, but aromatic L-amino acid decarboxylase- and dopamine-negative. Most of these neurons were small, round or oval in shape, and ranged from 10 to 20 μm in diameter with their long axonal processes extended within the third ventricular wall. By immunoelectron microscopy, L-DOPA-positive products were observed throughout the cytoplasmic matrix and its terminal processes which contained small (60 to 80 nm) or large (140 to 160 nm) vesicles.