[Effect of caffeine on the Ca2+-transport function of sarcoplasmic reticulum vesicles in the rat myocardium].

The effects of caffeine on active transport of Ca2 by heavy and light fractions of rat myocardial microsomes were investigated with the use of a Ca2+-selective electrode and nephelometry. It was found that under the effect of caffeine (5 mM) the rate of Ca2 transport in the presence of oxalate decreased by 30 to 40%. The caffeine-induced inhibition was prevented by ruthenium and tetracaine, thus suggesting the inhibitor specificity.