Studies on the calcium antagonistic action of tetrandrine: XIII. Protective effect of tetrandrine on myocardial hypoxia and necrosis induced by isoproterenol in rats

Abstract

The protective effect of tetrandrine (Tet) on myocardial hypoxia and necrosis induced by isoproterenol (Iso) in rats has been investigated.

After administration of Iso (3 mg/kg s.c.), electrographical changes within 48 h were examined at first.

In the acute experiment, Tet (100 mg/kg s.c.) reduced the depression of T wave and SαT segment due to myocardial hypoxia induced by Iso (3 mg/kg s.c.). In subacute experiment, the electrographical changes of myocardial injury and necrosis caused by Iso (5 mg/kg s.c. sx2), inversion or biphasic pattern of T waves, elevation of SαT and the appearance of Q (q) wave were all alleviated by Tet too.

It was suggested that as a calcium antagonist Tet had a protective effect on myocardial hypoxia and necrosis induced by Iso in rats through blocking calcium influx into the cell.

Keywords

tetrandrine / isoproterenol / myocardial hypoxia / isoproterenol induced myocardial necrosis

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