拘束冷应激对大鼠肾脏热休克蛋白表达和血清皮质醇含量的动态影响

目的：研究拘束冷应激对大鼠肾脏组织热休克蛋白（heat shock protein 70,HSP70）表达和血清中皮质醇（Cortisol,CORT）含量的动态影响及可能的机制。方法：选取50日龄清洁级大鼠77只,随机分为7组,即0、0.5、1.0、1.5、2.0、2.5和3.0 h。采用拘束冷应激法,应激相应时间后,用免疫组织化学方法观察大鼠肾脏组织HSP70的表达,并检测血清中CORT含量。结果：血清中的CORT浓度在1.5 h呈现最高值,其余各时点变化不明显。光镜下可见HSP70在肾小球毛细血管内皮细胞的胞核及肾小管上皮细胞的胞核和胞浆中均有表达。肾脏中HSP70的表达首先呈增加的趋势,1.5～2.5 h HSP70持续高表达（P〈0.01）,之后下降（P〈0.05）。结论：适当强度的拘束冷应激能诱导肾脏组织中HSP70的合成,并且随着时间的延长而增加,但过度的拘束冷应激则可能降低或阻断肾脏HSP70的表达。

The dynamic effects of cold restraint stress on heat shock protein expression in kidney tissues and serum corticos-teroid content in rats

Objective：To study the dynamic effects of cold restraint stress on HSP70 expression in kidney and serum corticosteroid content in rats,and explore its possible mechanism.Methods：Seventy-seven 50-day-old SD rats were randomly divided into 7 groups,namely 0 h,0.5 h,1.0 h,1.5 h,2.0 h,2.5 h and 3.0 h group.At corresponding restraint stress time,the expression of HSP70 in kidney tissues were tested by means of immunohistochemistry and the level of CORT in serum was also examined.Results：The level of CORT reached its peak in 1.5 h group,but there was no significant difference in other groups.Under the light microscope,the expressions of HSP70 in the nuclei of renal glomerular capillary endothelial cells,in the nuclei and cytoplasm of renal tubular epithelial cells could be observed.The HSP70 expression in kidney increased continuously first,then it was kept in a high level at stress time of 1.5 h,2.0 h and 2.5 h（P0.01）,and since then it declined gradually（P0.05）.Conclusion：Suitable cold restraint stress can induce the synthetic of HSP70,and it increased with stress time.While excessive cold restraint stress may decreased or block the expressions of HSP70 in kidney.