Efeito da inibição da enzima conversora de angiotensina no desenvolvimento folicular, dopplerfluxometria e expressão gênica ovariana em bovinos

Abstract

The aim of this study was to evaluate the effect of inhibition of the Angiotensin Converting Enzyme (ECA) with enalapril maleate, on blood pressure, follicular growth, ovulation rate, utero-ovarian hemodynamics, P4/E2 concentrations and gene expression of follicular cells. Were used 31 Nelore (Bos indicus) cows. The females were synchronized with progesterone/estradiol-based protocol and then treated with enalapril maleate (0.5 mg/kg/day) or placebo (NaCl 0.9%) throughout the protocol (10 days). A half of the synchronized cows (n=17) were ultrasonographically evaluated for monitoring the follicular dynamics and utero-ovarian dopplerflowmetry. A half of animals (n=14) were submitted to follicular aspiration guided by ultrasound Ovum pick up (OPU) for measurement of the follicular hormonal synthesis and gene expression. There was no effect of enalapril on arterial pressure, in utero-ovarian hemodynamics and follicular and luteal growth. The ovulation rate (%) was significantly higher in the enalapril treated cows. The plasma and intrafollicular concentrations of progesterone and estradiol not differed significantly between treatments. The enalapril altered significantly the gene expression of enzymes P450aromatase, ECA2 and MAS receptor in the granulosa cells of dominant follicles.