Water and Exchangeable Sodium in Goldblatt Two-Kidney, Two-Clip Hypertensive Rats

Abstract

Exchangeable ²²Na (ExNa), total body water (TBW) and the inulin space (InSp) were determined in two kidney, two-clip (2K-2C) hypertensive and sham operated (normotensive) control rats 6–8 weeks after surgery. TBW (ml/kg lean body weight) was the same in hypertensive and sham rats. In contrast, ExNa (mEq/kglbw) and InSp (ml/kglbw) significantly increased (p < 0.01) in rats whose hypertension did not exceed 170 mmHg. Consequently, sham, moderate hypertensive (< 170mmHg) and severe hypertensive (< 170 mmHg) animals showed equal TBW but differed in body water distribution in that modrately hypertensive animals displayed a redistribution of water in favor of the extracellular space.

Key Words:

• body fluids
• sodium
• hypertension
• renovascular hypertension