In accordance with the findings on the key role of the cardiomyocite electrolyte homeostasis abnormality in dysfunction and coronary insufficiency-related alterative changes in the contractile myocardium and positive results of correction of the above abnormalities with Ca2+ antagonists morphofunctional aspects were studied of cardioprotective action of finoptin in its course administration in experiments in rabbits. General histological techniques were used together with transmission electron microscopy and cytochemical tests. The drug under study has been shown to increase the cardiomyocite glyco-calyx Ca(2+)-depositing function and to diminish its quickly-exchanging fraction on a plasmolemma. The benefits derived from the aforesaid under conditions of recurring coronary insufficiency include membrane-stabilizing effect, optimization of the energy balance and plastic processes in cardiomyocytes, with their ability to adjust themselves to conditions of the simulated pathology enhanced.