[Influence of thyrocalcitonin on the adenosine triphosphatase activity and the electrolyte balance of the rat myocardium].

The effect of thyrocalcitonine on the calcium, sodium and potassium levels in the blood plasma of the rats' myocardium and also on the activity of Na+-, K+- and Ca2+- ATP-ase of the sarcoplasmatic cardiac reticulum fragments were studied in experiments with rats. Calcitonine was found to force down the level of calcium in the blood plasma and to raise the sodium content in the myocardium on rats. The drug lessened the activity of the myocardial Na+-, K+-ATP-ase.