LONG-TERM EXPOSURE OF WISTAR RATS TO HIGH DIETARY-SODIUM CHLORIDE LEVEL .1. CHANGES IN AORTIC CONNECTIVE-TISSUE COMPONENTS

The effect of chronic salt loading on aortic components of connective tissue was evaluated in normotensive Wistar rats maintained on a high sodium chloride (NaCl; 8%) regime for a period of 30, 90, 180 and 360 days. The blood pressure remained unchanged until 90 days and was significantly elevated thereafter. The high NaCl diet for 180 days influenced neither the serum levels of both total cholesterol and triglyceride nor the aortic contents of collagen, elastin and glycosaminoglycans (GAG) derived from the proteoglycans. The only significant change associated with a 360-day massive NaCl ingestion was the increased aortic concentration of total GAG due to an increase in chondroitin sulfate, dermatan sulfate and heparan sulfate rather than hyaluronic acid. This study suggests that an increase in the contents of sulfated GAG occurred in the late stage of hypertensive aorta of NaCl loaded rats might be responsible, at least in part, for the pathogenesis of atherosclerotic cardiovascular disease.