AJP - Heart and Circulatory Physiology, Vol 242, Issue 3 376-H380, Copyright © 1982 by American Physiological Society
Interstitial fluid dynamics in conscious renal hypertensive rats
N. C. Trippodo
Interstitial fluid pressure (IFP) was measured in conscious rats with
one-kidney one-clip Goldblatt hypertension using implanted capsules. No
significant differences in IFP were found between rats with hypertension of
3, 28, or 56 days duration and the one-kidney controls. To estimate
interstitial compliance in the 28-day hypertensive and control rats,
hyperosmotic albumin solution was infused intravenously. The subsequent
transfer of tissue fluid into the intravascular space was associated with
increased diuresis and decreased IFP. The changes in tissue fluid volume
(TFV) were estimated from the changes in plasma volume and urine output. In
the hypertensive rats 3 h postinfusion, TFV decreased by 36.3 +/- 2.9
ml/kg, and IFP decreased from -1.2 +/- 0.2 to -4.7 +/- 0.6 mmHg. In the
normotensive rats TFV decreased by 36.7 +/- 2.7 ml/kg, and IFP decreased
from -1.2 +/- 0.2 to -4.3 +/- 0.4 mmHg. Interstitial compliance, estimated
from the regression of delta IFP and delta TFV, averaged 7.3 +/- 1.2 and
8.1 +/- 0.7 ml.kg-1.mmHg-1 (P greater than 0.5) in the hypertensive and
normotensive rats, respectively. These results suggested that the rats with
one-kidney one-clip Goldblatt hypertension had normal interstitial fluid
dynamics.
