RÉSUMÉ
Objective To explore whether combined olmesartan angiotensin Ⅱ receptor type 1 blocker(ARB) and angiotensin-converting enzyme inhibitor(ACEI) temocapril have synergistic effect on reversal of left ventricular hypertrophy (LVH) in stroke-prone spontaneously hypertensive rats (SHRsp). Methods Fourty-four SHRsps and 11 Wistar-Kyoto rats(WKY) were divided randomly into 5 groups:WKY-control group, SHRsp-control group, SHRsp-olmesartan 10 mg/(kg?d)group, SHRsp-temocapril 10 mg/(kg?d)group, and SHRsp-Olmesartan 3 mg/(kg?d)+temocapril 3 mg/(kg?d) group for 6 weeks. Hearts weight were measured and histologically studied. The mRNA expression of angiotensin Ⅱ receptor type 1(AT1R) and integrin ?1 in myocardium was detected by RT-PCR. Results Olmesartan, temocapril and the their combination significantly reduced systolic blood pressure in a similar magnitude. Combination therapy was shown not greater effect in reversal of LVH than by olmesartan alone, although the effect by both of them was greater than temocapril monotherapy. The mRNA levels of AT1R and integrin ?1 in SHRsp were significantly decreased by treatment with olmesartan, temocapril, or combination therapy. Olmesartan and combination therapy result in greater decreases in expression of AT1R and integrin ?1 mRNA in myocardium than that by temocapril. Conclusion Compared with olmesartan alone, the combination of ARS and ACEI didn't show synergistic effect on reversal of left ventricular hypertrophy as were down-regulation of AT1R and suppression of integrin ?1 mRNA in myocardium.