AJP - Heart and Circulatory Physiology, Vol 273, Issue 1 303-H309, Copyright © 1997 by American Physiological Society
Skeletal muscle ischemia-reperfusion causes transitory increase in microvascular protein permeability
A. M. Kupinski, D. E. Bock and D. R. Bell
Department of Physiology, Albany Medical College, New York 12208, USA.
The aim of this study was to determine whether the length of ischemia in
skeletal muscle influences the return of normal microvascular permeability
during reperfusion in addition to influencing the size of the initial
changes. In anesthetized rabbits, the transvascular clearance of labeled
albumin was measured in the gastrocnemius and soleus muscles during the
first, second, third, or fourth hour of reperfusion after 1, 2, 3, or 4 h
of ischemia. The size of the increases in albumin clearance, tissue water,
and myeloperoxidase activity during the first hour of reperfusion was
dependent on the length of ischemia. The return of the albumin clearance to
control values during the fourth hour of reperfusion was independent of the
length of ischemia. Tissue water, extravascular mass of native albumin, and
myeloperoxidase activity remained elevated during the 4 h of reperfusion.
After 4 h of ischemia, the solvent-drag reflection coefficient for albumin
was significantly less than control during the first hour of reperfusion.
The value during the fourth hour of reperfusion was not significantly
different from control. These results suggest that the inflammatory
mediators producing a change in permeability are washed out of the
microvasculature during the first few hours of reperfusion.
