Effect Of Controlled Hypotension On TNF-α And IL-6 In Lung Of The Different Hemorrhagic Rats

Objective:To observe the influences of controlled hypotention(CH) induced by sodium nitroprusside(SNP)and esmolol(ESM)on the change of TNF-αand IL-6 in the different hemorrhagic rats,to explore the rats' tolerance with different hemorrhage after controlled hypotension.Method:48 Sprague-Dawley rats weighing 260-350g,are randomly divided into group C(hemorrhage)and group H(controlled hypotention + hemorrhage).According to the hemorrhage,group C are randomly divided into group C1,C2,C3,C4(hemorrhage of 10%,20%,30%, 40%),and group H are randomly divided into group H1,H2,H3, H4(hemorrhage of 10%,20%,30%,40%).In group H,the mean arterial pressure(MAP)are to be keep 50-55mmHg with sodium nitroprusside(SNP)and esmolol(ESM)for ten minutes,then let blood from the femoral.The group C are continus infused 0.9%physiological saline solution(NS),then let blood from the femoral.All the groups rise the MAP a hour later.Recording vital sign of rats and doing blood gas analysis,observing lung tissue morphological change and detecting TNF-αand IL-6 in the lung with immunohisto chemical staining respectively after 24 hours.The survival rate of the rats are also recorded.Result:1.One day after hypotension,survival rate in group C were respectively:100%,100%,100%,50%,and survival rate in group H were respectively:100%,100%,83%,17%.The mortality in group H4 were significantly higher than group H1,H2, H3(p＜0.05).The mortality in group C4 were significantly higher than group C1,C2,C3(p＜0.05).2.HE staining:There were no obvious abnormality in the lung of group C1,C2,H1,H2.There were angiectasis,inflammatory infiltration and interstitial edema in the lung of group C3,H3.It is the same case of group C4 and H4.3.The expression of TNF-αin lung in group H3 is greatly higher than other groups(p＜0.05).Because of the high death rate,the group C4 and H4 are excluded4.The expression of IL-6 in lung in group C1,C2,H1,H2 had little difference(p＞0.05).group H3 is higher than group C3(p＜0.05).Because of the high death rate,the group C4 and H4 are excludedConclusions:1.The lung of rats can tolerate the hemorrhage of 10%and hemorrhage of 20%without significant change of TNF-αand IL-6 under controlled hypotension。When the hemorrhage is upto 30%,the expression of JNF-αand IL-6 is increasd significantly.In this case,the increase of them imply the early stage of lung injury.2.The rats cann't tolerate the hemorrhage of 40%whether controlled hypotension or not,having a high mortality,the main cause may be the bad toleration of brain and heart.