Venous Wall Electrolytes and Hexosamines in Hypertensive Rats 1

Abstract

The relationship between vascular wall water, sodium, and glycosaminoglycans in experimental hypertension was investigated by measurements of the water, electrolyte, and hexosamine content of the vena cava in 43 one-clip, one-kidney Goldblatt hypertensive and in 22 spontaneously hypertensive (SHR) rats. Twenty-eight sham-operated normotensive and 21 normotensive Wistar-Kyoto rats served as controls. Compared to values obtained in normotensive control rats, the sodium content of the vena cava was increased by 12.5 and 16.4% in rats with mild (systolic BP < 180 mm Hg) and severe (>180 mm Hg) Goldblatt hypertension, respectively. In contrast, an increase in the water and hexosamine content of the vena cava, 13.2 and 25.1%, was found only in the more severly hypertensive Goldblatt rats. It is, therefore, unlikely that the binding of sodium to acidic glycosaminoglycans is an important mechanism accounting for the accumulation of venous wall sodium in renal hypertensive rats. An increase in venous wall hexosamine content, however, may play a role in the waterlogging of veins. There were no significant changes in the composition of the vena cava in SHR with either mild or moderate hypertension.