The effects of angiotensin I and angiotensin II on the isolated tracheal muscle of the cat.
The effects of Asp1-beta-amide-Val5-angiotensin II (A II) and Asp1-Ile5-angiotensin I (A I) have been studied on the isolated continuously superfused cat tracheal muscle contracted by 5-hydroxytryptamine (5-HT). Both peptides have been shown to induce dose-dependent relaxation on this muscle. Similar effects have been obtained with synthetic bradykinin, prostaglandin E2 (PGE2), noradrenaline and histamine. The effects of bradykinin, A I and A II have been shown to be inhibited by aspirin but not by propranolol, metiamide, SC 19220 or a specific, competitive antagonist of A II. The relaxing effect of A I is not due to the conversion of decapeptide to octapeptide A II. The possible mechanism of the relaxing effects of A I and A II on the cat isolated tracheal muscle is discussed.
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001241:Aspirin / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology; D002415:Cats; D012531:Dibenz(b,f)(1,4)oxazepine-10(11H)-carboxylic acid, 8-chloro-, 2-acetylhydrazide / Q000494:pharmacology; D004347:Drug Interactions; D006632:Histamine / Q000494:pharmacology; D066298:In Vitro Techniques; D008785:Metiamide / Q000494:pharmacology; D009130:Muscle, Smooth / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D011433:Propranolol / Q000494:pharmacology; D011458:Prostaglandins E / Q000494:pharmacology; D013722:Teprotide / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects
D011458:Prostaglandins E; D000804:Angiotensin II; D012531:Dibenz(b,f)(1,4)oxazepine-10(11H)-carboxylic acid, 8-chloro-, 2-acetylhydrazide; D008785:Metiamide; D006632:Histamine; D011433:Propranolol; D013722:Teprotide; D001241:Aspirin; D001920:Bradykinin; D009638:Norepinephrine