This study investigated the protective effects of
Compound 21 (
C21), the first specific non-
peptide AT2 receptor agonist, on cardiac injury in rats with
isoproterenol-induced
heart failure in vivo and compared it with
valsartan, an AT1 receptor antagonist. In this study, 56 Wistar albino male rats (estimated
body weights 250-400 g) were divided into eight groups (n = 7). Group 1 (Control) received no drug. Group 2 (ISO) was given 180 mg/kg of
isoproterenol subcutaneously (s.c.); two doses were administered at 24-h intervals on days 29 and 30 of the experiment. Groups 3, 4, and 5 were given
valsartan (30 mg/kg orally),
C21 (0.03 mg/kg intraperitoneally), and a combination of Valsartan + C21, respectively, for 30 days. Groups 6, 7, and 8 were administered
Valsartan,
C21, and Valsartan + C21 in the same application, duration, and dose, respectively, and
isoproterenol (180 mg/kg s.c.) was given on days 29 and 30 of the experiment. Transthoracic echocardiography was performed on the rats at the beginning and end of the experiment. Blood pressure, heart rate, and ECG alterations were monitored via a carotid artery
cannula at the end of the experiment. Histopathological and biochemical measurements were performed on the cardiac tissue of the rats. For histopathological findings,
C21 and Valsartan + C21 combination
therapy significantly reduced the development of
heart failure compared to
valsartan alone. Also, the protective effect of
C21 on myocardial injury was superior to that of
valsartan. According to the results of echocardiographic and biochemical evaluations,
C21, and
Valsartan showed protective effects against
heart failure.
C21,
valsartan, and combined
therapy significantly prevented the decrease of ejection fraction. This report describes the cardioprotective effects of
C21 and
valsartan in ISO-induced myocardial damage.