Abstract
The ethanol extract of dried fruits of Embelia ribes Burm (Myrsinaceae) was evaluated for protection against isoproterenol (ISO)-induced myocardial infarction in albino rats. The cardiotoxicity induced by ISO (5.25 and 8.5 mg/kg,. s.c., for two consecutive days) was indicated by a significant increase (P < 0.01) in heart rate and systolic blood pressure, elevated levels of lactate dehydrogenase (LDH) and creatine kinase (CK) in serum, with increased thiobarbituric acid reactive substances (TBARS), and reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) levels in heart homogenates, as compared to normal healthy control rats. Microscopical examination (histopathology) was also performed on the myocardial tissue. Pretreatment with ethanol Embelia ribes extract (200 mg/kg, p.o., 40 days) significantly (P < 0.01) decreased the elevated levels of LDH and CK in serum and myocardial TBARS and increased the reduced levels of GSH, SOD and CAT in heart homogenates in ISO-induced myocardial infarction in albino rats. Histopathological observation revealed a marked protection by the extract in myocardial necrotic damage. The results of our study, for the first time, provide clear evidence that ethanol Embelia ribes extract treatment enhances the antioxidant defense against ISO-induced myocardial infarction in rats and exhibit cardioprotective properties.