ABSTRACT
Objective To investigate the regulation effect of irbesartan on the expression of angiotensin-converting enzyme 2 (ACE2) mRNA in the kidney of spontaneously hypertensive rats (SHR). Methods Twenty 14-week-old male SHR were randomly divided to SHR group (n=10) and irbesartan group (n=10); ten 14-week-old male WKY group were served as control. Irbesartan group was given a daily dose of 50 mg/kg irbesartan for 12 weeks by gavage and the other two groups were fed with a normal diet. ACE2 in kidney was examined by immunohistochemistry and RT-PCR. Plasma angiotensin II in each group were estimated by radioimmunoassay (RIA). Results The ACE2 mRNA expression was significantly down-regulated in the kidney of SHR group compared with WKY group (0. 72?0. 11 vs 1. 11?0. 15). After 12 weeks treatment with irbesartan, the attenuated ACE2 expression in irbesartan group was markedly enhanced compared with SHR group (1. 03?0. 13 vs 0. 72?. 0. 11). ACE2 mRNA expression in SHR kidney was correlated significantly with plasm angiotensin II level. (r = 0. 83, P