AJP - Heart and Circulatory Physiology, Vol 263, Issue 4 1064-H1070, Copyright © 1992 by American Physiological Society
Transvascular albumin and IgG flux in skin after a continuous 3-h bradykinin infusion
J. R. Wallace and D. R. Bell
Department of Physiology and Cell Biology, Albany Medical College, New York 12208.
Bradykinin (1 microgram/min) was infused into the femoral artery of one
hindleg of anesthetized rabbits for 3 h. Measurements of the initial
extravascular uptake for labeled albumin and immunoglobulin (Ig) G were
compared with measurements of the lymph protein flux for endogenous albumin
and IgG. With bradykinin, the initial extravascular uptake for both albumin
and IgG, calculated as the 1-h extravascular distribution space at plasma
concentration divided by time and expressed as a plasma clearance, was 12
times the control values. For both proteins, the lymph fluxes were not
significantly greater than the values for extravascular uptake, indicating
that the sustained increase in lymph protein flux was not due to washout of
interstitial protein. The extravascular uptake for IgG was approximately
80% of that for albumin in both control and bradykinin animals, suggesting
that the sustained response did not change the selectivity between the two
proteins. Changes in the extravascular masses of endogenous albumin and IgG
suggest that the initial response to bradykinin was a transient formation
of endothelial gaps that did not restrict transvascular IgG transport more
than albumin.
