CYTOKINE STIMULATED ENDOTHELIN RELEASE FROM ENDOTHELIAL-CELLS

Endothelin release from bovine endothelial cells of the aorta, pulmonary artery, and retinal microvessels was measured in response to various cytokines. Transforming growth factor-beta (0.05-5 ng/ml) was found to be a potent stimulator (3-4 fold increase) of endothelin secretion in all three cell types. Tumour necrosis factor-alpha (0.1-10 ng/ml) and interferon-gamma (8-800 U/ml) had a small (1.5-2 fold increase) but significant effect on endothelin secretion from endothelial cells of large vessels but not the retinal microvessels. Interleukin-1-beta, Interleukin-6 and interleukin-8 at various doses did not affect endothelin secretion. These effects were observed at various time points from 6-24 hrs and indicate that of the cytokines tested, only transforming growth factor beta has a potent effect on endothelin release from endothelial cells of different organs.