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

摘要:

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。

Abstract:

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.