BLOCKERS OF VOLUME-ACTIVATED CL- CURRENTS INHIBIT ENDOTHELIAL-CELL PROLIFERATION

Volume-activated Cl- currents (I-Cl,I-vol) and cell growth have been m easured in cultured endothelial cells from bovine pulmonary artery (CP AE) in the absence and presence of compounds which block these current s. The anti-oestrogen drug tamoxifen, which efficiently arrests the gr owth of breast cancer cells (l), inhibits both I-Cl,I-vol and cell pro liferation with IC50 of 3.8 and 4.8 mu mol/l respectively. NPPB and qu inine, which also block I-Cl,I-vol, inhibit the growth of CPAE cells a s well. Current and cell growth were closely correlated under all thes e conditions. We conclude that I-Cl,I-vol might be involved in the con trol of endothelial cell growth and thus might be important for the mo dulation of vascularisation and vascular remodelling.