急性胰腺炎肺损伤大鼠肺组织肿瘤坏死因子受体-1与窖蛋白-1的表达及清胰汤的治疗作用

The expression of tumor necrosis factor receptor-1 and caveolin-1 in the lung of acute pancreatitisassociated lung injury rats and the therapeutic role of Qingyitang

目的 观察肿瘤坏死因子受体-1（TNFR-1）和窖蛋白-1（Cav-1）在急性胰腺炎肺损伤大鼠肺组织的表达及功能,探讨清胰汤的可能作用机制.方法 Wistar大鼠随机分为假手术组、模型组、地塞米松治疗组、清胰汤治疗组.经胰胆管逆行注射脱氧胆酸钠建立大鼠急性胰腺炎肺损伤模型.24 h后采血和肺组织,检测血清淀粉酶、肺湿/干重比值和肺组织病理切片判定损伤程度 放免法检测血清肿瘤坏死因子-α（TNF-α）水平 逆转录-聚合酶链反应（RT-PCR）和Western blot分别检测肺组织中TNFR-1和Cav-1的mRNA及蛋白表达.结果 模型组血清淀粉酶、肺湿/干重比值、血清TNF-α（4.82±0.14比2.96±0.30,P＜0.01）和肺组织病理损伤程度均明显升高 肺组织TNFR-1的mRNA表达上调（1.29±0.15比0.43±0.05,P＜0.01）,而Cav-1的mRNA表达则下调（1.14±0.10比2.00±0.10,P＜0.01） 脂筏内外表达的TNFR-1均升高,尤以脂筏内升高明显,而Cav-1则表达下降.与模型组比较,地塞米松和清胰汤组的血清淀粉酶、肺湿/干重比值、血清TNF-α（地塞米松组：3.79±0.11,清胰汤组：3.66±0.10,模型组：4.82±0.14,P＜0.01）和肺组织病理损伤程度均下降 肺组织TNFR-1的mRNA表达下降（地塞米松组：0.48±0.01,清胰汤组：0.49±0.02,模型组：1.29±0.15,P＜0.01）,而Cav-1的mRNA则表达升高（地塞米松组：1.66±0.06,清胰汤组：1.52±0.04,模型组：1.14±0.10,P＜0.01） 脂筏内外表达的TNFR-1均下降,而Cav-1则上升.结论 TNF-α/TNFR-1的表达增加和Cav-1表达的下降与急性胰腺炎肺损伤密切相关.地塞米松和清胰汤都能够明显降低TNFR-1的表达并上调Cav-1的表达,有效减轻肺损伤程度,这可能是清胰汤治疗急性胰腺炎肺损伤的作用机制之一.

Objective To investigate the expression and function of tumor necrosis factor receptor-1 （TNFR-1） and caveolin-1 （Cav-1） in the lung of acute pancreatitis-associated lung injury rats, and to determine the potential role of Qingyitang. Methods Wistar rats were randomly divided into sham operation （SHAM） group, acute lung injury （ALI） group, dexamethasone （DEX） group and Qingyitang （QYT）group. ALI was induced by retrograde injection of deoxycholate into biliopancreatic duct of rats. Blood and lung tissues were drawn after 24 h. Serum amylase, lung wet/dry （W/D） ratio and pathological section were examined to evaluate the degree of lung injury. Immunoradioassay was used to detect serum tumor necrosis factor-α （TNF-α）. Reverse transcription-polymerase chain reaction （RT-PCR） and Western blotting were applied to detect the expression levels of TNFR-1 and Cav-1 mRNA and protein respectively. Results The concentration of serum amylase, the W/D ratio, TNF-α （4.82 ± 0.14 vs 2.96 ± 0. 30, P 〈0. 01 ） and the degree of pathological lung injury were obviously increased in ALI rats. The expression of TNFR-1 mRNA was increased in ALI rats （1.29 ±0. 15 vs 0.43 ±0.05,P〈0.01）, but Cav-1 mRNA expression was decreased （ 1.14 ±0. 10 vs 2.00 ±0. 10,P 〈0.01 ）. The expression of TNFR-1 protein in both lipid rafts and non-lipid rafts was increased, but that of Cav-1 in both of the two fractions was decreased. As compared with ALI rats, the concentration of serum amylase, W/D ratio, TNF-αt （ DEX： 3.79 ± 0. 11,QYT： 3.66 ±0. 10, ALI： 4.82 ±0. 14,P 〈0.01 ） and the degree of pathological lung injury were obviously decreased in DEX and QYT rats. The expression of TNFR-1 mRNA was decreased in both DEX and QYT groups （DEX： 0.48±0.01, QYT： 0.49 ±0.02, ALI： 1.29 ±0. 15,P〈0.01）, but that of Cav-1 mRNA was up-regulated （DEX： 1.66 ±0.06, QYT： 1.52 ±0.04, ALI： 1.14 ±0. 10,P〈0.01）. The expression of TNFR-1 protein in both lipid rafts and non-lipid rafts was decreased, but that of Cav-1 protein was increased.Conclusion The up-regulated expression of TNF-α/TNFR-1 and the down-regulated expression of Cav-1 suggest that both of them may play an important role in acute pancreatitis-associated lung injury. DEX and QYT may relieve lung injury effectively by regulating the expression of TNFR-1 and Cav-1.