Hypothalamus manufactures and secretes hypothalamic regulatory hormones which control the secretion of adenohypophysical hormones. It is also the site for the synthesis of the two neurohypophysial hormones. Several of these hypothalamic hormones possess unique structural features--carboxamide groups at the COOH-terminal and 5-oxoprolyl (pyroglutamyl) residues at the NH2 terminal. The proposed research is aimed at characterizing the enzymatic processes which are responsible for the synthesis of these terminal groups. It is proposed that the enzymes be purified and their properties such as specificities, reaction intermeidates, and regulations be studied. Eventually these enzymes will be localized to the various cell-types in the hypothalamus thus providing knowledge as to the precise sites of synthesis of these hormones.