[Specific antagonism between angiotensin II and several of its analogs].
The authors studied comparatively the properties of two angiotensin II analogues, a new compound (1-hydantoin acid, 5-valine, 8-alanine)-angiotensin II (compound III) and (1-asparagine, 5-valine, 8-alanine)-angiotensin II (compound II), as of the myotropic action of angiotensinamide (these experiments were conducted on the rat isolated ascending colon); pressor action of the hormone was investigated in experiments on anesthetized rats. A competitive character of the antagonism--within the range of low concentrations of the analogues--10(-10)--10(-9) M/l--was revealed in vitro. No antagonism was expressed against the nonspecific myotropic agents--acetylcholine and bradykinin. In vivo compounds II and II manifested the antagonistic action against angiotensinamide beginning from the doses of 100 and 50 gamma/kg, respectively.
D000804:Angiotensin II / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D003106:Colon / Q000187:drug effects; D066298:In Vitro Techniques; D009130:Muscle, Smooth / Q000187:drug effects*; D051381:Rats
D000804:Angiotensin II
O spetsificheskom antagonizme mezhdu angiotenzinom II i nekotorymi ego analogami