Effect of losartan on myocytes in myocardium-infarcted rats

With the Langendorff infusion and the isotope-labeled substrate uptake, we investigated the mechanism of losartan on the isolated myocytes from myocardium-infarcted rats. This study showed that the synthesis rates of RNA (14C-UR) and protein (3H-Leu) in MC from control MI group are significantly higher than those from the shamoperated (SO) one treated with the same concentration of Aug , respectively. On the other hand, the uptake rates of 3H-Leu, 14C-UR of MC from MI group treated with losartan or captopril are not significantly different from those of the SO one, respectively. These effects of Aug n on MC are abolished completely by angiotensin receptor antagonist-losartan, angiotensin antagonists-1.8 Aug and angiotensin antipeptide. The findings suggest that losartan could prevent the syntheses of RNA and protein in the MC treated with Aug ; Losartan could reduced the myocardial hypertrophy and the responsiveness of Aug on the MC from uninfarcted area.