Protective effect of Ginkgo biloba against experimental cardiotoxicity induced by isoproterenol in adult male albino rats a histological and biochemical study

ABSTRACT

The present study was designed to investigate whether Ginkgo biloba [GB] might protect the heart against myocardial injury induced by isoproterenol [ISO] on the basis of its effects on biochemical and histological parameters. Twenty four adult male albino rats [180-200 g] were used in this study. They were divided into 4 equal groups of six rats each. Group I was the control group and group II received ISO [85 mg/kg body weight [bw], subcutaneously [S.C.] for two consecutive days to induce myocardial injury. Group III received GB [200 mg/kg bw] orally by gastric gavage daily for 21 days while group IV received GB [200 mg/kg bw] orally daily for 21 days in addition to ISO [85 mg/kg bw], S.C. on the 20th and 21st day from starting GB. After 24 hours, rats were sacrificed and the levels of cardiac marker enzymes [creatine kinase-CK] and its myocardial isoenzyme [CK-MB]] were assessed in serum. Heart specimens were processed for light and electron microscopic examination. Administration of GB before ISO significantly prevented ISO-induced elevation of serum cardiac marker enzymes. Light and electron microscopic findings of the heart pretreated with GB revealed a well preserved normal morphology of cardiac muscle with minimal evidence of myocardial injury when compared to ISO-treated hearts. This study demonstrated that GB had a significant effect in the protection of heart against myocardial injury induced by ISO. This beneficial effect was mostly related to its antioxidant property. The results of the present investigation may trigger an interest towards the use of GB in myocardial infarction