Neutrophils mediate the enhanced ischemia-reperfusion induced capillary fluid filtration associated with hypercholesterolemia. Harris, Norman R., and D. Neil Granger. Department of Physiology and Biophysics, Louisiana State University Medical Center, Shreveport, LA
APStracts 3:0146H, 1996.
Fluid filtration rate (Jv/S) from individual mesenteric capillaries in normocholesterolemic and hypercholesterolemic rats was measured prior to and following 30 minutes each of ischemia and reperfusion (I/R). The median I/R-induced increase in Jv/S (I/R vs. baseline) was 44% in normocholesterolemic rats (N=11) and 97% in hypercholesterolemic rats (N=11). A positive correlation slope of .20% per mg/dl resulted when plotting the % Jv/S increase versus plasma cholesterol concentration (p=.02), demonstrating that hypercholesterolemia enhances the capillary response to I/R. Since microvascular pressure did not change significantly following I/R in either group of rats, the increments in Jv/S likely reflect increased capillary permeability. In hypercholesterolemic rats rendered neutropenic with antineutrophil serum, I/R did not elicit a significant increase in Jv/S, suggesting that activated neutrophils mediate the exaggerated endothelial barrier dysfunction associated with hypercholesterolemia.

Received 7 November 1995; accepted in final form 29 March 1996.
APS Manuscript Number H1043-5.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 16 April 96