Angiotensin II regulates cardiac hypertrophy via oxidative stress but not antioxidant enzyme activities in experimental renovascular hypertension.
The aim of this study was to provide new insights into the role of angiotensin II and arterial pressure in the regulation of antioxidant enzyme activities in a renovascular model of cardiac hypertrophy. For this purpose, aortic coarcted rats were treated with losartan or minoxidil for 7 days. Angiotensin II induced cardiac hypertrophy and oxidative stress via Nox4, p22(phox) and p47(phox), which are components of the NAD(P)H oxidase. Antioxidant enzymes were regulated by arterial pressure and were not implicated in cardiac hypertrophy. Heme oxygenase-1, the rate-limiting enzyme in heme catabolism, behaved as a catalase and glutathione peroxidase, and is regulated by arterial pressure. In summary, the present report indicates that cardiac hypertrophy, induced by renovascular hypertension, depends on angiotensin II through reactive oxygen species and is not prevented by the action of antioxidant enzymes.
Polizio
Ariel H
AH
Department of Biological Chemistry, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
Balestrasse
Karina B
KB
Yannarelli
Gustavo G
GG
Noriega
Guillermo O
GO
Gorzalczany
Susana
S
Taira
Carlos
C
Tomaro
Maria L
ML
D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D001794:Blood Pressure; D006332:Cardiomegaly / Q000209:etiology*; D002374:Catalase / Q000378:metabolism; D005978:Glutathione / Q000032:analysis; D006978:Hypertension, Renovascular / Q000150:complications* / Q000378:metabolism; D019808:Losartan / Q000494:pharmacology; D008297:Male; D019255:NADPH Oxidases / Q000378:metabolism; D018384:Oxidative Stress; D051381:Rats; D017208:Rats, Wistar; D013482:Superoxide Dismutase / Q000378:metabolism
D000804:Angiotensin II; D002374:Catalase; D013482:Superoxide Dismutase; D019255:NADPH Oxidases; D005978:Glutathione; D019808:Losartan