Effects of angiotensin II on isolated toad (Bufo arenarum) aortic rings.
1. The vascular response to Asn1-Val5 angiotensin II (A II) in aortic rings from Bufo arenarum toad was studied. 2. Tachyphylaxis in response to A II could be abolished after incubation with norepinephrine (NE). 3. Phentolamine treatment partially inhibited the pressor effects to A II. 4. Sar1-Ile8 A II and Sar1-Ala8 A II significantly attenuated the vascular effects of A II and did not affect the NE response. 5. We conclude that the pressor response to A II has a direct contractile effect and a catecholamine dependent component in aortic rings of Bufo arenarum toad.
Peral de Bruno
M
M
Departamento de Fisiología, INSIBIO, San Miguel de Tucumán, Argentina.
Lebenshon de Chialvo
P
P
Coviello
A
A
D000804:Angiotensin II / Q000494:pharmacology*; D000818:Animals; D001011:Aorta / Q000187:drug effects; D002022:Bufo arenarum; D066298:In Vitro Techniques; D007537:Isometric Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009638:Norepinephrine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D013997:Time Factors
D000804:Angiotensin II; D009638:Norepinephrine; D010646:Phentolamine