Effects Of Telmisartan On The Expression Of Myocardiac Calsarcin-1, Arterial Angiotensin Ⅱreceptors And Peripheral Angiopoietin-2 In Renovascular Hypertensive Rats

Objective To explore the changes of myocardial calsarcin-1 level , arterial angiotensinâ…¡receptors level, plasma angiopoietin-2 and Ang-II level in different stages of cardiac hypertrophy by renovascular hypertensive (two-kidneys, oneclip, 2K1C) rat models, and the effects of telmisartan.Methods 24 Male Sprague-Dawly rats were randomly divided into control group (n=8), sham operation group (n=8), 2 kidney 1 clip (2K1C) group (n=12) and 2K1C+telmisartan group(n=12). 2K1C hypertensive model was established in Sprague-Dawly rats by chronic partial occlusion of left renal artery. Before and after eight weeks of the operation, blood pressure were tested by arterial catheterization, the myocardial structure and function were obtained by ultrasonography, and the serum angiopoietin-2 and Ang-II were evaluated by ELISA, calsarcin-1 expression level in myocardium and AT1R, AT2R expression level in aorta were compared by western blotting.Resultsâ‘ Eight weeks later, the blood pressure and the thickness of left ventricle in 2K1C group were significantly higher than that of control group and sham group (P<0.01). Compared with 2K1C group, the blood pressure and the the thickness of left ventricle were significantly decreased in 2K1C+ telmisartan group(P<0.01).â‘¡The serum level of angiopoietin-2 was markedly increased in 2K1C group, and was closely related to the blood pressure and the extent of myocardial hypertrophy, but was not decreased in 2K1C+telmisartan group(P>0.05). The Angâ…¡level in 2K1C group and telmisartan group were both increased (P<0.05 and P<0.01 respectively).â‘¢Compared with sham group, the calsarcin-1 level was markedly increased in 2K1C group(P<0.01), and after being treated for 8weeks, the calsarcin-1 level was higher than which of untreated group(P<0.05).â‘£The AT1R level was markedly increased in 2K1C group(P<0.05), but AT2R was not increased(P>0.05),Compared with 2K1C group,AT1R,AT2R were both increased in telmisartan group(P>0.05).Conclusionsâ‘ Serum level of Angiopoietin-2 is increased in the renovascular hypertensive rats, and is related to myocardial hypertrophy. Telmisartan can reduce blood pressure and prevent myocardial hypertrophy, but can not decreased the angiopoietin-2 level, which indicate that telmisartan prevent myocardial hypertrophy maybe not associated with angiopoietin-2 level.â‘¡The decreased myocardiac calsarcin-1 level occurs in the early stage of cardiac hypertrophy and participates in its development, Telmisartan may increase calsarcin-1 level, which maybe one of mechanisms reversing cardiac hypertrophy by telmisartan.â‘¢Telmisartan can increase AT2R level, which is related to blood pressure.