DOPA ACCUMULATES IN THE HYPOTHALAMIC-HYPOPHYSEAL PORTAL VESSELS AND IS TAKEN INTO THE ANTERIOR-PITUITARY OF NSD-1015-TREATED RODENTS

DOPA was measured in the anterior pituitary and hypothalamic-hypophysi al portal blood after treatment with NSD-1015, a DOPA decarboxylase in hibitor. NSD-1015 caused DOPA to accumulate in the anterior pituitary of mice and rats, and increased DOPA in the hypothalamic-hypophysial p ortal blood of rat. Serum prolactin was also increased. Interruption o f the anterior pituitary blood supply from the hypothalamic-hypophysia l system by cannulation of the entire pituitary stalk eliminated the N SD-1015-induced DOPA accumulation in the rat pituitary. We conclude th at DOPA can be taken into the anterior pituitary from the portal blood of NSD-1015-treated rodents and that the anterior pituitary lacks tyr osine hydroxylase activity in both mice and rats.