Tissue cations and water in arterial hypertension

Human hypertensive subjects were found to have an increased sodium and water concentration in renal artery and psoas muscle. Hypertensive rats showed a high water content in their aortas. If the water and sodium content were increased in hypertensive arterioles as well as arteries, the swelling of the arteriolar walls would narrow the lumens enough to account for much of the increased peripheral resistance. Low sodium diets may alleviate hypertension by lowering the sodium and water contents in arteriolar walls toward normal values.