OS 32-02 EFFECTS OF RENIN-ANGIOTENSIN SYSTEM INHIBITORS ON VAGINA AND CARDIAC EXPRESSION OF RAAS COMPONENTS IN FEMALE SPONTANEOUSLY HYPERTENSIVE RATS.

OBJECTIVE: The role of the renin angiotensin aldosterone system (RAAS) and the gene variants of its components in hypertension have been investigated in various studies. A local tissue-specific renin-angiotensin system (local RAS) has considered as a regulator of cardiovascular physiology and homeostasis. However, no report has described the vagina protective efficacy of RAS inhibitors including ARB and ACEI. Therefore, we aim to investigate the effect of ARBs and ACEI on the vagina and cardiac expression of the local renin-angiotensin components.

DESIGN AND METHOD: 16 week-old female spontaneously hypertensive rats (SHRs) were randomly divided into control, hypertension, benazepril-treated (10 mg/kg.d), valsartan-treated (15 mg/kg.d), and ben + val (5 mg/kg.d + 7.5 mg/kg.d)-treated groups. Real-time polymerase chain reaction was used to detect mRNA expression of angiotensin II type 1 receptor (AT1R), ACE, ACE2, and angiotensin-(1-7) receptor (MasR). The cardiac structure and function were measured by echocardiography.

RESULTS: BP was higher in SHR than in WKY rats at baseline, after 12 weeks treatment, BP of SHR markedly reduced in every administered group. The antihypertensive effects were similar for the two treatment groups. Expression levels of AT1R and ACE in vagina and cardiac were significantly elevated in the hypertension group compared to the control group. The mRNA expression of antihypertensive components such as ACE2 and MasR were greater increased in the benazepril-treated group compared to valsartan group. Benazepril and valsartan, decreased the mRNA expression of ACE and AT1R, but increased the mRNA expression of ACE2 and MasR in cardiac and vagina tissue.

CONCLUSIONS: RAS inhibitors such as ARBs and ACEI play a protective role in heart and vessels. These results indicate that the change tendency of RAS components expression in vagina were consistent with heart after administrated. It is likely that vagina is also one of the target organs that could be protected by the anti-hypertensive drugs. However, the precise potential mechanism remains unclear.