A0793 Comparative effects of renin angiotensin system inhibitors on vaginal vascular remodeling and fibrosis in female hypertension

Abstract

Objectives: Female sexual dysfunction (FSD) is more frequently encountered in hypertensive women. This research intents to compare the potential beneficial effects of Angiotensin converting enzyme inhibitors (ACEI) and Angiotensin receptor 1 antagonists (ARB) on vascular remodeling and fibrosis in female lower genital tract, to provide evidences for the choice of therapy in hypertensive women with FSD. Methods: Twelve-week old female SHRs and WKY rats were allocated to four groups: SHR (N = 9) received no treatment but vehicle; SHR + Irb (N = 9) received Irbesartan; SHR + Ben (N = 9) received Benazepril; and control WKY (N = 9) received vehicle. After 12 weeks, vaginal tissues were excised for real-time PCR and western blot analysis. Results: Vaginal RAS expression altered in untreated SHRs compared to WKY. A reduction of AT1R expression was observed in SHR + Irb and SHR + Ben. Irbesartan up regulated AT2R, MasR and ACE expression, and remarkably increased ACE2 expression. On the contrary, AT2R, MasR and ACE expression were down regulated in SHR + Ben group. Significant increase of vaginal α-SMA was observed in untreated SHRs as compared with WKYs, also the reduction of eNOS. Both irbesartan and benazepril elicited a marked decrease in vaginal α-SMA expression, and caused increments of eNOS expression. There was no significant difference in vaginal α-SMA and eNOS in SHR + Irb and SHR + Ben. However, vaginal Col III was lower in SHR + Ben compared with SHR + Irb, which was decreased slightly compared with untreated SHRs. Conclusion: Despite different influences on RAS, ACEI and ARB have similar positive effects against oxidative stress and vascular remodeling in female lower genital tracts. However, Benazepril decreased vaginal Col III more than Irbesartan. Both ARB and ACEI are reasonable choices for women with FSD.