Effect of chronic treatment with bark of Terminalia arjuna: a study on theisolated ischemic-reperfused rat heart

Dried pulverized bark of Terminalia arjuna Linn (TA) was administered orall y to Wistar albino rats (120-150 g) in two doses [500 and 750 mg/kg in 2% c arboxy methyl cellulose (CMC)], 6 days per week for 12 weeks. Thereafter, r ats were sacrificed either for determination of baseline changes in cardiac endogenous antioxidant compounds [superoxide dismutase (SOD), reduced glut athione (GSH) and catalase (CAT)] or the hearts were subjected to oxidative stress associated with in vitro ischemic-reperfusion injury (IRI). There w as significant increase in the baseline contents of thiobarbituric acid rea ctive substance (TBARS) (a measure of lipid peroxidation) with both doses o f TA. However, only in the 500 mg/kg treated group, this was accompanied by a simultaneous increase in SOD, GSH and CAT levels, but not in the 750 mg/ kg treated group, where only CAT was raised. Significant rise in myocardial TBARS and loss of SOD, CAT and GSH (suggestive of increased oxidative stre ss) occurred in the vehicle-treated hearts subjected to in vitro IRI. Only hearts, harvested from the 500 mg/kg rats treated rats, were significantly protected from oxidative stress, when subjected to in vitro IRI. The result s suggest that crude bark of TA augments endogenous antioxidant compounds o f rat heart and also prevents oxidative stress associated with IRI of the h eart. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.