Effect of a Low Sodium Diet on Electrolyte Composition of Arterial Wall

Abstract

Normal rats on a low Na diet have 12% less Na in their aortas per unit of dry weight than rats on the regular Na intake of ordinary rat chow, a significant difference. This sizeable drop in aorta Na on the low Na diet is accompanied by a very slight rise in serum Na concentration. Aortas of the rats on the low Na diet also have a significantly greater P content than the aortas of rats on the regular Na intake. This is an increase in P content in relation to both total solids and intracellular solids. There was no significant difference between the 2 groups in regard to water, K, and Mg content of the aorta. The average blood pressure of rats on the low Na diet was 10 mm Hg lower than the rats on ordinary chow, but the difference was not statistically significant. The observed changes in aorta composition after a low Na diet may be related to the tendency toward lower arterial blood pressures seen in rats on such a diet.