Resveratrol (trans-3,4',5-trihydroxystilbene- RES), is a natural antioxidant found in various
fruits and vegetables and is abundant in grapes. It has beneficial effects against coronary heart
diseases. This study aims to explore the protective and therapeutic effects of resveratrol on
cadmium chloride induced toxicity on isolated toad's hearts. Electrocardiogram (ECG) was
recorded before and after direct perfusion of cadmium chloride (CdCl2) and resveratrol.
Application of CdCl2 (2mM/L) into isolated toad's heart significantly decreased the heart rate
(HR) accompanied by an elongation in the conduction time (P-R interval), while a non
significant decrease of the ventricular contraction (R-wave amplitude) was observed within
minutes (5-30 min) of CdCl2 application into isolated toad's. Pretreatment of isolated toad's
hearts with RES (21μM/L) five min before CdCl2 application abolished the severe bradycardia
and negative inotropic effect induced by CdCl2, this was accompanied by improvement of
cardiac disorders induced by this toxic heavy metal. While, post treatment of RES after
appearance of cardiac abnormalities induced by CdCl2 didn't affect these induced disorders. In
conclusion, the obtained investigation indicates that RES could serve as a protective agent
against some of acute ( CdCl2) toxicity on isolated toad's heart than more that its therapeutic
efficacy. However, low level of resveratrol at was not effective in preventing either neither sever
bradycardia nor in reducing ventricular dysfunction induced by cadmium.