adrenomedullin (22 52) (human) (trifluoroacetate salt)

Adrenomedullin (22-52) is a C-terminal fragment of adrenomedullin (1-52) . In vitro, adrenomedullin (22-52) reduces basal corticosterone production in a mixture of rat adrenocortical and adrenomedulllary cells. It also reverses increases in ACTH-stimulated corticosterone production induced by adrenomedullin (1-52). Adrenomedulin (22-52) (0.5 and 5 μg/kg/min) has no effect on basal regional cerebral blood flow but reverses increases in regional cerebral blood flow induced by rat adrenomedullin in rats. Unlike adrenomedullin (1-52), adrenomedullin (22-52) has no effect on mesenteric arterial perfusion pressure in cats.

Adrenomedullin (13-52) is a truncated form of adrenomedullin (1-52) . It induces nitric oxide-dependent relaxation of and inhibits release of angiotensin II and endothelin-1 from isolated rat aorta. In vivo, adrenomedullin (13-52) decreases mean arterial pressure (MAP) in spontaneously and renal hypertensive rats in a dose-dependent manner. Adrenomedullin (13-52) (10-3,000 ng per animal) reverses increases in lobar arterial pressure induced by U-46619 in a dose-dependent manner in cats but has no effect on basal lobar arterial pressure or systemic arterial pressure. It also potentiates inflammatory edema and neutrophil accumulation in rats.

Adrenomedullin consists of 52 amino acids and is a member of the adrenomedullin family. It s a a hypotensive peptide and has 1 intramolecular disulfide bond. It seems that adrenomedullin has a slight homology with the calcitonin gene-related peptide. Adrenomedullin has a highly expression in pheochromocytoma and adrenal medulla. It also can be detected in lung, ventricle and kidney tissues. Adrenomedullin and PAMP are potent hypotensive and vasodilatator agents. Numerous actions have been reported most related to the physiologic control of fluid and electrolyte homeostasis. In the kidney, adrenomedullin is diuretic and natriuretic, and both adrenomedullin and PAMP inhibit aldosterone secretion by direct adrenal actions. In pituitary gland, both peptides at physiologically relevant doses inhibit basal ACTH secretion. Both peptides appear to act in brain and pituitary gland to facilitate the loss of plasma volume, actions which complement their hypotensive effects in blood vessels. It is believed that adrenomedullin functions through combinations of the calcitonin receptor like receptor and receptor activity-modifying proteins complexes, as well as CGRP receptors.