Enalapril does not prevent the myocardial ischemia caused by the chronic inhibition of nitric oxide synthesis.
In rats, chronic administration of the nitric oxide (NO) inhibitor N omega-nitro-L-arginine methyl ester (L-NAME) causes arterial hypertension, cardiac hypertrophy and myocardial ischemic alterations such as necrosis and fibrosis. In this study, we evaluated the effect of 8 weeks of treatment with enalapril maleate on cardiac weight and on the development of the histological alterations induced by L-NAME. Enalapril significantly inhibited the development of both arterial hypertension (117.2 +/- 5.8, 161.8 +/- 8.8 and 122.0 +/- 10.6 mm Hg, for control, L-NAME- and L-NAME + enalapril-treated animals, respectively) and left ventricular hypertrophy (1.36 +/- 0.13, 1.60 +/- 0.04 and 1.48 +/- 0.05 mg/g, for control, L-NAME- and L-NAME + enalapril-treated animals, respectively), but had no effect on the myocardial lesions. These findings demonstrate that although the renin-angiotensin system plays a major role in the development of arterial hypertension and cardiac hypertrophy, it does not modulate the ischemia-induced myocardial alterations observed in this model.
Moreno
H
H
Department of Pharmacology, UNICAMP, Campinas, Brazil.
Piovesan Nathan
L
L
Pereira Costa
S K
SK
Metze
K
K
Antunes
E
E
Zatz
R
R
De Nucci
G
G
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000037:antagonists & inhibitors*; D001120:Arginine / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors; D004656:Enalapril / Q000494:pharmacology*; D006321:Heart / Q000187:drug effects; D008297:Male; D017202:Myocardial Ischemia / Q000145:classification / Q000517:prevention & control*; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000037:antagonists & inhibitors* / Q000096:biosynthesis; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents; D009569:Nitric Oxide; D004656:Enalapril; D001120:Arginine; D019331:NG-Nitroarginine Methyl Ester