创伤性休克大鼠多脏器TNF-α表达的变化及意义

The significance of TNF - α expression in diverse organs of trauma shock rats

目的研究TNF-α在创伤性休克大鼠多脏器中的表达变化，探讨TNF-α在创伤性休克发生发展过程中的意义。方法取健康成年SD大鼠56只，体质量200～300g，雌雄各半，随机分为对照组，复苏组和休克1、2、4、8、24h组，每组8只，观察各组的死亡率，分别采用RT-PCR法及免疫组化法测定各组肝、脑组织的TNF-αmRNA和肝、脑、肺、肾组织的TNF-α蛋白表达水平。结果对照组和复苏组大鼠均无死亡，休克1h组死亡率为1／8，2h和4h组死亡率为2／8，8h组死亡率为4／8，24h组死亡率为5／8；TNF-αmRNA表达在休克后2h明显升高，肝组织TNF-αmRNA表达水平高于脑组织（p〈0．05）；肺、肝、肾组织的TNF-α蛋白表达在休克1h后即开始升高（P〈0．05），脑组织TNF-α蛋白表达水平较低，趋势不明显，但复苏组的肝、脑组织的TNF-αmRNA和蛋白表达较对照组无明显升高（P〉0．05）。结论创伤性休克早期以低血容量表现为主，主要不是由TNF-α介导的；而后期则与TNF-α水平升高相关。

Objective To observe the difference of TNF - α expression in diverse organs of trauma shock rats and investigate the significance of TNF - α during this kind of shock. Methods The normal Sprague - Dawley rats were divided randomly into seven groups of eight per group, which included controls, resuscitation rats, 1 h, 2 h, 4 h, 8 h and 24 h shock rats. The mortality of all groups was assessed. The reverse transcriptase polymerase chain reaction （RT - PCR ） and immunohistochemistry were respectively used to investigate the transcription and expression of TNF -α in liver, brain, lung and kidney. Results The eontrols and resuscitation rats had no death, and the mortality of 1 h, 2 h, 4 h, 8 h and 24 h shock rats were 12. 5% , 25% , 25% , 50% and 62. 5%. The TNF - α transcription increased significantly in liver and brain of 2 h shock rats, and the one was more obvious in liver（P 〈 0. 05 ）. The TNF - α protein level began to increase in lung, liver and kidney （ P 〈 0. 05 ） , but not brain in 1 h shock rats. The transcription and expression of TNF - α in liver and brain had no differences between resuscitation and control rats（ P 〉 0. 05 ）. Conclusion Hypovolemia is the main manifestation in the early stage of trauma shock, which not mediated by TNF - α, while TNF - α plays a part in the later stage of the shock.