title: Vasopressor activities of N-terminal fragments of adrenomedullin in anesthetized rat.
abstract: Adrenomedullin (AM) is a vasorelaxant peptide that was recently isolated from human pheochromocytoma. In contrast to human (h) AM, which has vasodepressor activity, a synthetic N-terminal fragment of hAM, hAM-(1-25)-NH2 showed vasopressor activity in the anesthetized rat. The N-terminal peptides hAM-1-31)-NH2, hAM-(1-25)-OH, hAM-(1-21)-NH2, acetyl-hAM-(16-21)-NH2, and acetyl-hAM-(16-36)-OH all showed vasopressor activities. The potency of hAM-(1-21)-NH2, acetyl-hAM-(16-21)-NH2 was greater than that of hAM-(1-25)-NH2. Pretreatment with phenoxybenzamine, guanethidine, or reserpine attenuated vasopressor activities of these peptides. These data suggested that vasopressor activity of N-terminal fragment of hAM is due to a stimulation of endogenous catecholamine release.
authors.affiliation: Peptide Institute, Inc., Protein Research Foundation, Osaka, Japan.
authors.forename: T X
authors.initials: TX
authors.lastname: Watanabe
authors.forename: Y
authors.initials: Y
authors.lastname: Itahara
authors.forename: T
authors.initials: T
authors.lastname: Inui
authors.forename: K
authors.initials: K
authors.lastname: Yoshizawa-Kumagaye
authors.forename: K
authors.initials: K
authors.lastname: Nakajima
authors.forename: S
authors.initials: S
authors.lastname: Sakakibara
mesh_terms: D000310:Adrenal Gland Neoplasms / Q000737:chemistry; D053607:Adrenomedullin; D000768:Anesthesia, General; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D003243:Consciousness; D006145:Guanethidine / Q000494:pharmacology; D006801:Humans; D008297:Male; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000494:pharmacology*; D010455:Peptides / Q000302:isolation & purification / Q000494:pharmacology*; D010643:Phenoxybenzamine / Q000494:pharmacology; D010673:Pheochromocytoma / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012110:Reserpine / Q000494:pharmacology; D013329:Structure-Activity Relationship; D014665:Vasodilator Agents / Q000494:pharmacology*
chemical_list: D010446:Peptide Fragments; D010455:Peptides; D014665:Vasodilator Agents; D010643:Phenoxybenzamine; D053607:Adrenomedullin; D012110:Reserpine; D006145:Guanethidine