中文摘要：

目的研究梯度热打击对体外培养大鼠肝库普弗细胞吞噬功能及分泌功能的影响。方法设置培养库普弗细胞的热打击温度梯度（37、39、41、43℃）,使用PI及Hochest33342染色细胞检测热打击后细胞受损情况,采用CCK-8法检测细胞增殖率,流式细胞术检测库普弗细胞对溶菌酶吞噬能力的改变。结果与正常对照组相比,热打击各组均出现不同程度的细胞损伤,且随热打击程度加深而加重（P〈0.05）。细胞增殖实验显示,与正常对照组相比,热打击后6h,41℃和43℃组增殖率明显下降（P〈0.01）,12h时仅43℃组增殖率明显下降（P〈0.001）,至24h,各热打击组与正常对照组差异无统计学意义。流式细胞术显示,1h热打击结束后,与正常对照组相比,各热打击组细胞均呈现吞噬功能的下降,以43℃组最为明显（P〈0.05）。结论热打击可导致大鼠肝库普弗细胞吞噬功能受到抑制,可能与热打击对细胞的直接细胞毒作用有关。热打击对于肝库普弗细胞影响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 effect of gradient heat stress on phagocytosis of hepatic Kupffer cells （KCs） in vitro in rats. Methods Rat Kupffer cells were isolated in vitro and the temperature for gradient heat stress was set at 37, 39, 41 and 43℃. After thermal stimulation, cell injury was detected by PI and Hochest33342 staining. CCK-8 assay was used to investigate difference in cellular proliferation rate over 24h between the groups. Flow cytometry was used to investigate the influence of heat stress on the phagocytosis of KCs. Results Compared to the normal control group, cells in each heat stress group exhibited varying degrees of damage, especially cells in 43℃ group. The ratio of damage cells increased with the increase of heat stress severity （P〈0.05）. Proliferation assay indicated that the proliferation rate of cells in each heat stress group was significantly decreased in comparison with normal control group 6h after heat stress （P〈0.05）. After 12h recovery, decrease in proliferation rate was observed only in 43℃ group （P〈0.001）, and no difference in the rate of proliferation could be observed between the heat stress groups and normal control group after 24h recovery. Flow cytometry showed, that the phagocytosis of KCs decreased in heat stress groups compared with control group, especially in 43℃ group （P〈0.05）. This phenomenon disappeared after 24h recovery. Conclusion Heat stress can inhibit the phagocytosis of rat liver KCs through its cytotoxic effect on KCs, and subsequently inhibits its proliferative ability. Further investigation of the effect of heat stress on KCs may help understand the pathogenesis of heat stress.