AJP - Heart and Circulatory Physiology, Vol 245, Issue 6 911-H919, Copyright © 1983 by American Physiological Society
Effects of blood-free and protein-free perfusion on CFC in the isolated cat hindlimb
P. D. Watson
To investigate the effects of blood and protein on capillary filtration
coefficient (CFC), isolated cat hindlimbs were perfused at constant flow
from a reservoir containing one of three perfusates: 1) an electrolyte
solution also used for dialyzing bovine serum albumin (BSA) and hence
labeled dialysate, 2) dialyzed 6.5-7.0 g/100 ml BSA, labeled albumin, and
3) albumin plus cat blood, labeled control. CFC during control perfusion
averaged 0.0137 +/- 0.003 (SD, n = 26) and increased slowly with time. CFCs
with dialysate and albumin were 3.1 +/- 0.56 (n = 11) and 1.7 +/- 0.52 (n =
15) times control, respectively. However, the ratio in a particular
experiment depended on control CFC, the ratio being low when the control
CFC was low and high when control CFC was high. The data can be explained
if water flow occurs through two types of transcapillary pathways, one
having a hydraulic capacity constant from animal to animal and insensitive
to blood and protein, the second varying in hydraulic capacity and
requiring blood and protein for its normal values.
