Natriuretic peptides derived from pro-opiocortin
Gruber, K.A.; Klein, M.C.; Lymangrover, J.R.
Progress in Clinical and Biological Research 192: 213-220
1985
ISSN/ISBN: 0361-7742 PMID: 3001754 Document Number: 265645
Natriuresis in response to hypertonicity, volume loads, or high sodium diets has been proposed to be mediated by the release of a humoral factor(s), and controlled by the central nervous system. We have determined that the natriuretic activity of ACTH or alpha MSH resides in a common sequence, ACTH(4-10)/alpha MSH(4-10). Steric restriction of this peptide by replacement of an L-Phe residue with a D-Phe produced a superagonist. Gamma-2 MSH is a peptide derived from the 16K N-terminus of pro-opiocortin, which contains an ACTH(4-10)-like sequence. The natriuretic effect of gamma-2 MSH was maximal between 0.64 pmole to 64 pmole. Doses greater than 128 pmole produced no significant effects on renal sodium excretion. The regulated release of gamma MSH peptides may contribute to CNS regulation of renal sodium excretion.