The ionic composition of aortic smooth muscle from A.S.-hypertensive rats.

The Na(+), K(+) and Ca(2+) content of plasma and aortic vascular smooth muscle from normotensive and A.S.-hypertensive rats have been compared. There was no significant difference in the plasma concentrations of Na(+), K(+) and Ca(2+), or the Na(+), K(+) and water content or (3)H-inulin space of aortic tissue in the two groups.There was a marked increase in the amount of Ca(2+) in the aortae taken from the hypertensive animals as compared with the normotensive animals (P<0.01).