Changes in Aortic Water and Sodium Contents Associated with Potassium Supplement in Doca-Salt Rats

Abstract

Since waterlogging, increased vascular water and sodium contents, could contribute to the development of deoxycorticosterone acetate (DOCA)-salt hypertension, we have examined the effect of dietary potassium supplementation on the water and sodium contents of abdominal aorta after short-term (one week) treatment with DOCA while receiving a 1% NaCl solution to drink. Supplementation with 1% KCl solution could counteract blood-pressure rising action of DOCA-salt, associated with the inhibition of sodium retention. In addition, treatment with DOCA-salt was associated with increases in water (83.1±3.0%) wet weight) and sodium (118.7±2.8 μEq/g dry weight) contents of the aorta compared with those of the control rats (69.7±0.3%) wet weight and 103.0±4.0 μEq/g dry weight, respectively). In contrast, 1% KCl supplementation could attenuate the increase in water (73.2±1.5% wet weight) and sodium (110.3±2.3 μEq/g dry weight) contents of the aorta in DOCA-salt rats. Taken together, these results suggest that potassium supplement not only attenuates the sodium retention but also moderates the “waterlogging” in the vascular wall in DOCA-salt rats, thus leading to the antihypertensive action of potassium supplement in the early stage of DOCA-salt hypertension

Key Words:

• DOCA-salt hypertension
• natriuresis
• potassium supplement
• waterlogging