EVIDENCE FOR A PRECURSOR IN VASOPRESSIN BIOSYNTHESIS.

摘要: Infusion of 35S-cysteine into the third ventricle dogs for a period 1.5 hr did not yield significant quantities labeled vasopressin. However, animals sacrificed 4.5 after isotope infusion yielded 35S-vasopressin. If puromycin was administered from start experiment, then labeling vasopressin observed. Puromycin, had been infused, prevent subsequent appearance hormone either in vivo or with hypothalamic-median eminence (HME) slices incubated vitro. The HME slices, presence puromycin, gave rise to 35S- 3H-vasopressin only if vitro incubation preceded by 3H-tyrosine, respectively, dog prior sacrifice. It is suggested that biosynthesis occurs via intermediate formation precursor molecule which contains bound biologically inactive form. (Endocrinology 75: 943, 1964)