[Effect of calcium antagonists on the Ca2(+) paradox].

The model of calcium paradox was used to test the effect of the calcium entry blocker Diltiazem (concentration 4.0 mumol.l-1) and of the calmodulin inhibitor Trifluoroperazin (concentration 1.0 mumol.l-1). Application of each preparation resulted in improved cardiac function manifested by restoration of the electrical and contractile activity and by increased coronary flow. Both Diltiazem and Trifluoroperazin exerted a protective effect on the preservation of enzymatic activities and of ultrastructure in conditions of impaired calcium homeostasis.