Vascular endothelial growth factor increases hydraulic conductivity
of isolated perfused microvessels.
Bates, D. O., F. E. Curry.
Department of Human Physiology, School of Medicine, University of
California at Davis, Davis, CA 95616
APStracts 3:0258H, 1996.
These experiments report the first direct measurement of microvessel
permeability coefficients after exposure to Vascular Endothelial
Growth Factor (VEGF). The Landis technique was extended to enable
measurement of the resistance of the microvessel wall to water flow,
hydraulic conductivity (Lp) on the same microvessel in the frog
mesentery during the initial exposure to VEGF (acute) and 24 and 72
hours after initial exposure (chronic). Control measurements of Lp
showed no change either acutely or chronically. Exposure to 1nM VEGF
rapidly and transiently increased microvessel Lp within 30 seconds -
to 7.8 fold greater than baseline values - and returned to control
within two minutes. The baseline Lp was 5 fold greater after 24 hours
than the initial baseline as a result of VEGF perfusion and returned
to its original value after 72 hours. These experiments confirm the
hypothesis that VEGF acts both acutely (over a period of a few
minutes) and chronically (over a few hours) to increase microvascular
permeability.
Received 22 March 1996; accepted in final form 10 June 1996.
APS Manuscript Number H276-6.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96