Intracellular Na⁺ and Ca²⁺ in aortic smooth muscle cells after enzymatic isolation in spontaneously hypertensive rats

Summary

In aortic smooth muscle cells from spontaneously hypertensive and normotensive rats, which were separated from the blood vessels by enzymatic digestion, intracellular Na⁺ and Ca²⁺ activities were measured. The determinations were made by ion-selective electrodes. In smooth muscle cells from spontaneously hypertensive rats intracellular Na⁺ and Ca²⁺ activities were elevated as compared to cells from normotensive rats (P<0.001 for Na⁺ andP<0.01 for Ca²⁺). Since in cultured aortic smooth muscle cells from spontaneously hypertensive rats intracellular Ca²⁺ is known to be not significantly increased, primarily humoral factors may account for the changes in intracellular Ca²⁺ reported.