胸腺素α1对重症急性胰腺炎大鼠肺损伤作用的实验研究

Experimental study about effect of thymosin alpha l on lung injury in rats with severe acute pancreatitis

目的探讨胸腺素α1(Tα1)对重症急性胰腺炎(SAP)大鼠肺损伤的保护作用及可能机制。方法雄性SD大鼠24只随机均分为3组:对照组(A组)、重症急性胰腺炎组(B组)、Tα1干预组(C组)。经逆行胆胰管注射5%牛磺胆酸钠(0.1 ml/100 g)复制重症急性胰腺炎SD大鼠动物模型,C组在复制模型前30 min经腹皮下注射Tα1 6 mg/kg,复制模型后12 h处死大鼠。分别测定各组大鼠血清淀粉酶的含量,计算肺湿干比(W/D),Western blot法检测各组肺组织细胞间黏附分子(ICAM-1)及肿瘤坏死因子α(TNF-α)的蛋白表达;观察大鼠胰腺和肺组织病理学改变。结果 B、C组大鼠与A组比较,血清淀粉酶、肺组织ICAM-1及TNF-α的蛋白表达、W/D差异均有统计学意义(P<0.05),B、C组高于A组;C组与B组比较,血清淀粉酶、肺组织ICAM-1及TNF-α的蛋白表达、W/D差异有统计学意义(P<0.05),C组较B组降低,病理损伤较B组轻;A组无明显病理改变。结论 Tα1能够减轻SAP大鼠肺水肿严重程度,降低肺组织ICAM-1及TNF-α的蛋白表达水平,减轻肺损伤,对大鼠肺损伤具有一定的保护作用。

Objective To explore the protective effect of thymosin alpha l on lung injury in rats with severe acute pancreatitis（SAP） and its possible mechanism. Methods Twenty-four adult male Sprague-Dawley rats were randomly divided into three groups： control group（A）, severe acute pancreatitis group（B） and thymosin alpha l intervention group（C） with 8 in each group. Animal models of SAP were maken by retrograde injection of 5% sodium taurocholate（0.1 ml/100 g） into the cholangiopancreatic duct. The rats in the group C were treated with thymosin α1（6 mg/kg） by subcutaneous administration 30 min prior to SAP modeling. The rats from each group were sacrificed 12 h after SAP modeling. The selum level of amylase and lung W/D ratio were detected in each group. Intercelluar adhesion molecule 1（ICAM-1） and tumor necrosis factor-α（TNF-α） levels were studied using Western blot. Histopathological changes of pancreatic and pulmonary tissues were observed by light microscopy. Results The levels of serum amylase, the expressions of ICAM-1 and TNF-α in the lungs, the lung W/D ratio, and the lung and pancreas pathologic scores were increased in the groups B and C compared with the group A（P〈0.05）. The levels of serum amylase, the expressions of ICAM-1 and TNF-α in the lungs, the lung W/D ratio, and the lung and pancreas pathological scores in the group C were much lower than those in the group B（P〈0.05）. The changes of histopathology were milder in the group C. There was no obvious pathological changes in the group A. Conclusions Thymosin α 1 can decrease pulmonary edema, reduce pulmonary injury and has protective effect on lung injury in the rats with SAP by reducing the expressions of TNF-α and ICAM-1.