[Comparative analysis of the action of 2 calmodulin inhibitors on the contractile function of the isolated heart].

Ca2+-complexon EGTA and two calmodulin inhibitors: metaphenazine and trifluoperazine, induced similar effects on the cardiac contractile function: they diminished cardiac output, decelerated left ventricle pressure fall and increased both minimal--and end-diastolic pressure. Changes in the left ventricular pressure and its time course were more obvious during calmodulin inhibitor action as compared to EGTA at equal diminution of cardiac output. Trifluoperazine decreased left ventricular systolic pressure and resistance of coronary arteries to a greater extent than metaphenazine. The findings suggest participation of calmodulin in the regulation of myocardial relaxation mainly.