摘要：We investigated the effect of ammonium vanadate (vanadate) on ATP-induced increases in intracellular calcium ion level ([Ca2+]i) of human umbilical vein endothelial cells (HUVEC) by fluorescence confocal microscopic imaging using the Ca2+-sensitive probe Calcium Green 1/AM. The ATP analogue 2-methylthio-ATP (2meS-ATP), at 10 μ M , significantly increased the [Ca2+]i of HUVEC, and this was abolished by 1 μ M thapsigargin (a calcium pump inhibitor), whereas extracellular free calcium had no effect. Vanadate at 10 μ M also significantly increased the [Ca2+]i of HUVEC, which was abolished by 1 μ M thapsigargin. However, vanadate at 1 μ M did not exert such a significant effect. We thus examined the influence of ≤1 μ M vanadate for 24 h on 2meS-ATP-induced increase in [Ca2+]i. Vanadate significantly reduced the action of 2meS-ATP at 1 μ M but not at 0.1 μ M . Endogenously released ATP is known to induce various actions on endothelial cells. The present results suggest that vanadate exerts a regulatory influence on the function of vascular endothelial cells.
关键词：vanadium;ATP;P2Y receptor;human umbilical vein endothelial cell;intracellular calcium ion
