[The Ca2(+)-binding capacity of the thrombocytes in rats with hydrocortisone-induced steroid hypertension].

The Ca(2+)-binding ability of the thrombocytes' membranes did not change within 30 min after administration of hydrocortisone when no significant changes of arterial pressure occur. In stable increase of arterial pressure evoked by thrice repeated administration of hydrocortisone, a redistribution of the intracellular Ca2+ occurs: its contents decreases at the external plasmatic membrane and increases in intracellular membranes. The hypertensive response seems to coincide with the redistribution. The same mechanisms of Ca2+ metabolism disorders seem to underlie both essential and steroid hypertension. The cell's adrenoreceptor mechanisms are probably involved in the process.