Analysis of the effect of apocynin on the hipotensive responses induced by no donors in spontaneously hypertensive rats (SHR)

Abstract

The chronic treatment with NADPH oxidase inhibitors reduces the SHR arterial pressure. Because it is the main superoxide anion source in the aorta, the activity of this enzyme is related with the decrease of the NO bioavailability. The purpose of this study will be to test the hypothesis that the treatment with apocynin (NADPH oxidase inhibitor) modifies the hypotensive effect of the acetylcholine and of the exogenous NO donors, in SHR. Normotensive Wistar rats and SHR will be treated with apocynin (30 mg/ kg/ day, p.o.) from the fourth to the tenth week of life. During the treatment, the systolic blood pressure will be verified by tail plethysmography. It will be made in vivo experiments for the evaluation of possible changes in the arterial blood pressure (mean, systolic and diastolic), heart rate and in the hypotensive responses stimulated by acetylcholine, TERPY, a new NO-donor, and sodium nitroprusside (SNP).(AU)