中文摘要：

目的研究不同程度热打击对体外培养大鼠肠黏膜上皮细胞IEC-6的钙超载及钙超载相关的损伤。方法设置培养IEC-6细胞的温度梯度,Fluo-3Am探针加荧光显微镜及流式细胞术观察细胞内钙离子水平的改变,相差显微镜观察细胞形态学改变,考马斯亮蓝染色法观察细胞骨架变化,CCK-8法观察细胞活性改变,黏附实验观察基底膜黏附性改变。结果与正常对照组比较,热打击组细胞内钙水平上升（P〈0.01）,呈温度依赖性。热打击组细胞形态变圆,伪足变短,细胞间隙增大,45℃较43℃改变更为明显。考马斯亮蓝染色显示,热打击组细胞骨架增粗、紊乱,出现应力性纤维,45℃较43℃改变更为明显。CCK-8法显示,热打击组细胞活性下降（P〈0.01）,呈温度依赖性。基底膜黏附实验显示,热打击组基底膜黏附性显著下降（P〈0.01）,呈温度依赖性。结论热打击可造成IEC-6细胞钙超载,并造成与钙超载相关的一系列细胞损伤,热打击对于肠黏膜上皮钙超载的影响及其机制的进一步研究将有助于了解热射病的发病机制。

英文摘要：

Objective To investigate the e ect of gradient heat stress on calcium overload of rats’ enterocyte IEC-6 and calcium overload-related cell injury in vitro.Methods ermal gradient was set in culturing IEC-6 cells in vitro.A er thermal stimulation,Fluo-3Am probe with uorescence microscope or ow cytometry was used to detect the change in intracellular Ca2＋ concentration of IEC-6 cells.Phase contrast microscope was used to observe the morphological change in IEC-6.Coomassie blue dying method was employed to test the change in IEC-6 cytoskeleton.CCK-8 assay was used to assess cellular viability.Adhesion assay was applied to test the change in basilar membrane adhesiveness of IEC-6 cells.Results Compared with normal control group,cells of heat stress groups showed a thermal-dependent increase in intracellular Ca2＋ concentration（P＆lt;0.01）.Cells of heat stress groups were rounded in shape,the pseudopod was shorter,and cell space was enlarged.These phenomena were more obvious in 45℃ culture than in that of 43℃.Coomassie blue dying showed that the cytoskeleton of cells in heat stress groups became thickened and disordered,and stress fibers appeared.ese phenomena were also more obvious in 45℃ culture than in that of 43℃.A thermal-dependant decline of cell viability in heat stress groups was observed via CCK-8 assay（P＆lt;0.01）,and a thermal-dependant decline of basilar membrane adhesiveness in heat stress groups was observed via adhesion assay（P＆lt;0.01）.Conclusion Heat stress may cause calcium overload of IEC-6 cells,and thus resulting in a series of calcium overload-related cell injury.Further investigation of the e ect and mechanism of heat stress on calcium overload of intestinal mucosa endothelial cells may help further understand the mechanism of the pathogenesis of heat stroke.