Cell Na and K in the rat tail artery during the development of hypertension induced by desoxycorticosterone acetate.

An increase in total Na, due in large part to an increase in cell Na, was measured in the freshly excised rat tail artery during the course of DOCA-saline treatment. Since this change was associated with a fall in cell K, was first observed at 2 weeks, coincident with the rise in blood pressure, and was not sustained during subsequent immersion of the artery at zero pressure, it probably reflects the high in vivo intravascular pressure. In the incubated artery, cell Na is significantly reduced early in the course of treatment, while cell K falls late. Thus, Na transport in the artery is under direct attack from the start, but it is suggested that this leads to hypertrophy rather than to vasoconstriction.