AJP - Lung Cellular and Molecular Physiology, Vol 268, Issue 5 789-L800, Copyright © 1995 by American Physiological Society
Hypoxia induces capillary network formation in cultured bovine pulmonary microvessel endothelial cells
P. G. Phillips, L. M. Birnby and A. Narendran
Research Service, Stratton Department of Veterans Affairs Medical Center, Albany, New York, USA.
The development of new vessels (angiogenesis) is essential to wound
healing. The center of a wound space is hypoxic, a condition that has been
shown to stimulate angiogenesis in animal models of coronary artery
occlusion. Because the mechanisms involved in this complex process are
difficult to study in situ, an in vitro model would provide a useful
complement to in vivo studies. This laboratory has developed and
characterized calf pulmonary microvessel endothelial cell (PMVEC) cultures
and an in vitro model system of angiogenesis using collagen
three-dimensional gels that permit migration of cells into vessel networks.
This system was used to study the direct effect of normoxia (20% O2) or
hypoxia (5% O2) on PMVEC ability to undergo angiogenesis in vitro. Major
changes leading to formation of capillary-like networks occurred during the
first 3 days of hypoxic exposure only and included restructuring of actin
filament networks, focal changes in distribution of basic fibroblast growth
factor, and orientation and migration of cell tracts into a collagen gel
matrix to form vessel networks.
