THE RESEARCH FOR THE ATHEROSCLEROSIS AND THE CHANGE OF CELLULAR SIGNALING WITH REFERENCE TO THE AGING OF VASCULAR ENDOTHELIAL CELL

在这项研究中，我们可以用荧光指示剂Fura-2测定细胞内Na~+-K~+-ATPase活性、乙基异丙基阿米洛利敏感的Na~+/H~+逆向转运蛋白活性、胞内游离钙离子浓度([Ca~(++)]i)、用荧光指示剂2~7-双(羧乙基)羧基荧光素(BCECF)测定细胞内pH([pH]i)、用~(3 H)-胸腺嘧啶核苷掺入法测定人脐静脉内皮细胞(HUVEC)DNA合成。因此，我们研究了蛋白激酶C(PKC)激动剂佛波酯、蛋白激酶C(PKC)激活剂佛波酯、PKC抑制剂H-7、Na~+离子载体Monensin、细胞外钙离子通道阻滞剂(VDC)对上述参数的影响。HUVEC的[pH]i为7.17，[pH]i的维持主要依赖于乙基异丙基氨咪敏感的Na^+/H+逆向转运蛋白，部分依赖于细胞外钙离子通道或电压依赖性钙通道。ET可促进HUVEC产生前列环素和EDRF，而对[pH]i和[Ca^&lt；++&gt；]i无明显影响，这些作用与血管内皮细胞的收缩有拮抗作用。此外，内皮素对细胞增殖有抑制作用，提示存在自我调节机制，提示内皮素不仅对血管收缩有促进作用，而且对动脉硬化也有促进作用。

In this research we can measure the activity of Na^+-K^+ ATPase, the activity of ethylisopropylamiloride sensitive Na^+/H^+ antiporter, the cytosolic free calcium ion concentration ([Ca^<++>]i) using a fluorescent indicator fura-2, the intracellular pH ([pH]i) using a fluorescent indicator 2 7 -bis(carboxyethyl) carboxyfluoresein (BCECF) and the synthesis of DNA using the incorporation of ^3H-thymidine in human umbilical vein endothelial cells(HUVEC). Therefore we investigated the effect of endothelin, a protein kinase C(PKC) activator phorbol ester, a PKC inhibitor H-7, Na^+ ionophore monensin, extracellular Ca^<++> and a voltage dependent calcium channel(VDC) blocker on these parameters.The [pH]i in HUVEC is 7.17, and the maintenance of the [pH]i depends mainly on the ethylisopropylamiloride sensitive Na^+/H^+ antiporter, and depends partly on the extracellular Ca^<++> or the voltage dependent Ca^<++> channel. Endothelin enhanced the prostacyclin generation and the EDRF generation in HUVEC without effects on [pH]i and [Ca^<++>]i, these effects are antagonistic to the contraction for the smooth muscle cells. Furthermore endothelin has the suppression of the cell proliferation, this phenomenon suggests the presence of the autoregulatory mechanism, through these results it is suggested that endothelin has the acceleration effect on not only the vascular contraction but also the arteriosclerosis.