VASCULAR PERICYTES NOT ONLY REGULATE GROWTH, BUT ALSO PRESERVE PROSTACYCLIN-PRODUCING ABILITY AND PROTECT AGAINST LIPID PEROXIDE-INDUCED INJURY OF COCULTURED ENDOTHELIAL-CELLS

Interactions between vascular pericytes and endothelial cells were studied. Bovine retinal pericytes were found not only to inhibit growth of co-cultured human umbilical endothelial cells, but also to cause significant stimulation of prostacyclin production in the endothelial cells, both of which were achieved by close apposition of the two cell types. Substitution of a fibroblast feeder layer for the pericytes gave no change. Moreover, pericytes could confer protection against lipid peroxide-induced injury of endothelial cells, as determined by the release of [3H]-2-deoxy-D-glucose from radiolabeled endothelial cells. These results indicate that pericytes provide instructive signals to adjacent endothelial cells, helping to maintain microvascular homeostasis. © 1993 Academic Press. All rights reserved.