Cardioprotective and Antihypertensive Potential of Morus alba L. in Isoproterenol-Induced Myocardial Infarction and Renal Artery Ligation-Induced Hypertension

Abstract

The present study was aimed to evaluate the cardioprotective and antihypertensive effect of ethyl acetate soluble fraction of Morus alba L. in rats. Rats were orally treated with the ethyl acetate soluble fraction of methanol extract of Morus alba leaves (EASF 25, 50, and 100 mg/kg) for three weeks. Isoproterenol (85 mg/kg, s.c.) was administered at an interval of 24 h for two days for induction of myocardial infarction. The parameters like ST segment, heart rate, mean arterial blood pressure, pressure-rate index, vascular reactivity, heart weight, cardiac markers, and antioxidant enzymes were measured. Hypertension was induced by left renal artery ligation method. The effect of EASF was evaluated on blood pressure and cumulative concentration response curve (CCRC) of CaCl₂ on phenylephrine pre-ontracted isolated rat aortas. Oral administrati on of EASF signifi cantly reduced ST segment, heart rate, arterial pressure, pressure-rate index, heart weight, LDH, CK-MB, and SGOT, whereas the levels of antioxidant enzymes were increased significantly. EASF reduced the pressor response to catecholamines and also showed protection from hypertrophy and degenerative changes on myocardial muscles. The ligation of renal artery significantly increased the blood pressure and CCRC of CaCl₂ shifted to the left. EASF significantly reversed these changes. The observations propose that Morus alba may possess beneficial role in the treatment of myocardial infarction and hypertension through the regulation of antioxidant defensive mechanisms and blockade of calcium channels, respectively.