大黄对急性肺损伤大鼠热休克蛋白70表达的影响

目的探讨脂多糖(LPS)致急性肺损伤(ALI)中热休克蛋白70(heatshockprotein,HSP)的表达以及大黄对ALI的保护作用机制。方法用Wistar大鼠复制ALI的动物模型,动物随机分成四组:对照组、ALI组、大黄预防用药组、大黄治疗用药组,每组15只。大黄采用腹腔注射给药,分别于注射LPS或生理盐水后2h处死动物。用HE染色观察组织病理学改变,对ALI组和大黄用药组测定肺系数和动脉血氧分压(PaO2),并应用免疫组织化学和蛋白印迹方法检测组织中HSP70的表达。结果ALI组肺间质水肿,肺泡腔内可见大量中性粒细胞浸润和血浆蛋白渗出,肺血管内皮细胞损伤。ALI组HSP70的表达量较少,大黄用药组HSP70表达量增强。大黄用药组肺系数测定明显降低,PaO2明显升高。ALI组肺系数测定升高,PaO2降低。结论大黄对ALI的肺组织起保护作用,并且预防组强于治疗组。大黄能增加LPS诱导ALI组织中HSP70的表达,表明大黄对ALI的肺组织起保护作用与HSP70相关。

Effect of rhubard on heat shock protein 70 expression in rats with aute lung injury

Objective To investigate the expression of HSP70 in acute lung injury induced by endotoxin lipopolysaccharide(LPS) and the protective mechanisms of rhubard against ALI.Methods LPS was injected into rats via the internal jugular vein to induce ALI and rhubard extract was given by intraperitoneal injection. The rats were randomly divided into four groups: saline control group, LPS-induced ALI group,ALI treated with prophylactic rhubard group, and ALI treated with therapeutic rhubard group.The rats were sacrificed 2 hours after injection of LPS or saline. Physiological and pathological examinations were conduced,including arterial gas analysis,lung coefficient,hematoxylin-eosin staining ,and HSP70 expression(immunohistochemistry and Western blotting). Results In the LPS-induced ALI group,interstitial edema,neutrophil infiltration,plasma exudation in alveoli, and damaged vascular endotheliun were observed.HSP70 levels were slightly increased in LPS-treated rats,while HSP70 expression was enhanced significantly and overall lung function was improved in rhubarb-treated groups compared to ALI model rats.Conclusions Our study confirme that rhubard protects rats from LPS-induced ALI and upergulates HSP70 expression.Thus,the protective effect of rhubard may be mediated by the HSP70 signaling pathway.