Adrenomedullin, a newly discovered hypotensive peptide, is a potent bronchodilator.
The present study was designed to examine the effect of adrenomedullin (AM), a novel vasorelaxant peptide originally isolated from human pheochromocytoma, on histamine- or acetylcholine-induced bronchoconstriction in anesthetized guinea pigs in vivo. AM significantly inhibited acetylcholine-induced bronchoconstriction in a dose-dependent fashion. AM also significantly inhibited histamine-induced bronchoconstriction, but 10(-10) M AM had no significant inhibitory effect on this response. We also found that AM induced a long-lasting bronchodilator response, while isoproterenol induced transient bronchodilation. These preliminary findings suggest that AM may play important roles in airway function.
Kanazawa
H
H
First Department of Internal Medicine, Osaka City University Medical School, Japan.
Kurihara
N
N
Hirata
K
K
Kudoh
S
S
Kawaguchi
T
T
Takeda
T
T
D000109:Acetylcholine / Q000494:pharmacology; D053607:Adrenomedullin; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D016084:Bronchoconstriction; D001993:Bronchodilator Agents / Q000494:pharmacology*; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D010455:Peptides / Q000494:pharmacology*
D000959:Antihypertensive Agents; D001993:Bronchodilator Agents; D010455:Peptides; D053607:Adrenomedullin; D006632:Histamine; D007545:Isoproterenol; D000109:Acetylcholine