Endothelin-1 is expressed and released by a human endothelial hybrid cell line (EA.hy 926).

A permanent vascular endothelial cell line, EA.hy 926, was shown to express endothelin-1 (ET-1) mRNA and to secrete big ET-1 and ET-1 into culture medium. The concentration of both big ET-1 and ET-1 was significantly increased in EA.hy 926 culture medium by phosphoramidon, a metalloproteinase inhibitor, suggesting that phosphoramidon sensitive protease(s) may be responsible for the degradation of ET-1 and big ET-1. EA.hy 926 cells responded to various regulators of ET-1 similarly as primary human vascular endothelial cells. The production of ET-1 was increased by thrombin and decreased by vasodilators such as atrial natriuretic peptide, brain natriuretic peptide and nitroprusside, and by 8-bromo cyclic GMP and papaverine. This continuous human endothelial hybrid cell line could facilitate studies of regulation of ET-1 production in human endothelial cells, which in primary cultures have limited replication potential.