烧伤刺激介导内皮细胞蛋白激酶C的激活转位

The activation and translocation of protein kinase C induced by burn serum

目的 :探讨烧伤刺激对血管内皮细胞蛋白激酶 C(PKC)活性的影响。方法 :用 10 %烧伤血清分别刺激细胞 0、5、10、30和 6 0分钟后 ,通过细胞裂解和离心获得细胞浆和细胞膜蛋白粗提液。用同位素标记和液体闪烁计数法检测细胞浆和细胞膜的 PKC活性。 PKC的激动剂佛波酯醇 (PMA) 10 0 nm ol/L刺激细胞作为阳性对照组。选用 PKC特异性抑制剂 PKC(1936 )预处理细胞后 ,分别观察烧伤血清和 PMA介导的内皮细胞 PKC活性的变化。结果 :烧伤血清和 PKC的激动剂 PMA都可以激活内皮细胞的 PKC,并使其发生由胞浆至胞膜的转位 ;用 PKC的特异性抑制剂预处理细胞后可以分别抑制这种变化。结论 :烧伤血清可以介导内皮细胞 PKC的激活和转位 ;烧伤可以通过激活内皮细胞的

Objective:To study the effect of burn serum on the activation and translocation of endothelial cells.Methods:Confluent cultured endothelial cells were disintegrated to obtain cytoplasm and cellular membrane after being treated with burn serum or protein kinase C(PKC) activator PMA.PKC activity in cell membrane and cytoplasm was measured with radioactive isotope label method in a reaction system of phosphorylation of specific substrate MBP414 by PKC.For the control study,the PKC specific inhibitor PKC(1936) was used to pretreat the endothelial cells before the administration of PMA and burn serum.Results:Exposure to burn serum led to a rapid timedependent increase in membranebound PKC activity in cultured endothelial cells with a concomitant decrease in the cytoplasm fraction.Preincubating with PKC inhibitor abolished the effect of PMA.The effect of PMA was similar to that of burn serum.Conclusions:The results suggest that inflammatory mediators increase endothelial cellular PKC activity rapidly and induce a translocation of PKC,which probably could induce a series of physiological function changes,such as the increase in permeability of the endothelium.