【作者】 叶振宇；

【导师】 李军成；

【作者基本信息】 苏州大学 ， 普通外科学， 2008， 硕士

【摘要】 目的建立SD大鼠重症急性胰腺炎(SAP)动物模型,观察重症急性胰腺炎致急性肺损伤时肺组织的病理改变,观察肺微血管内皮细胞(PMVEC)β受体(β-AR)和肺组织G蛋白偶联受体激酶2(GRK2)与SAP肺损伤的关系以及甲基强的松龙的保护作用。方法采用雄性SD大鼠,随机分设对照组、实验组和干预组。对照组剖腹后十二指肠翻动找到胰腺随即关腹;实验组予5%牛磺胆酸钠(1 ml/kg)逆行胰胆管注射,制备SAP模型;干预组在制模后30 min臀部肌肉注射甲强龙(30mg/kg)。观察制模后6h和12h的相关指标:胰腺和肺大体病理改变(肉眼观),胰腺和肺镜下病理改变(HE染色),肺组织含水量(干湿重法),肺微血管内皮细胞的β-AR的最大结合容量Bmax和平衡解离常数Kd(放射配基结合实验),肺组织GRK2表达(免疫荧光),血清IL-6水平变化(ELISA法)。结果1实验组肺组织含水量在制模后6h可见明显升高,12h更为明显(P＜0.05),与同时段对照组比较有显著性差异(P＜0.01)。2.实验组β-AR最大结合容量Bmax在制模后6h可见明显降低,12h降低更为明显(P＜0.05),与同时段对照组比较有显著性差异(P＜0.01)。3.实验组β-AR平衡解离常数Kd在制模后6h可见升高,12h更加明显(P＜0.05),与同时段对照组比较有显著性差异(P＜0.01)。4.要验组肺组织GRK2表达在制模后6h即有升高,12h更加明显(P＜0.05),与同时段对照组比较有显著性差异(P＜0.01)。5.实验组血清IL-6水平在制模后6h可见升高,12h更加明显(P＜0.05),与同时段对照组比较有显著性差异(P＜0.01)。6.干预组与实验组比较:在6h,肺组织含水量减少,β-AR最大结合容量Bmax明显升高,β-AR平衡解离常数Kd可见降低,GRK2的表达显著降低,IL-6水平降低,有显著性差异(P＜0.05);在12h,各项指标变化更加明显,有显著性差异(P＜0.05)。结论1、SAP模型在制模后6h发现有肺损伤,12h更加严重。2、SAP模型肺微血管内皮细胞的β-AR是下调的。3、SAP模型肺组织GRK2表达显著增加,这可能是β-AR下调的重要机制,并与β-AR共同参与了SAP肺损伤的病理过程。4、甲强龙可以上调β-AR,降低SAP模型肺组织GRK2表达,减轻肺水肿,改善肺内炎症反应,降低血清IL-6水平,减轻大鼠SAP肺损伤的严重程度,对SAP肺损伤具有保护作用。更多还原

【Abstract】 Objective To investigate pathological changes,variation ofβ-AR in pulmonary microvascular endothelial cells and variation of GRK2 in lung and to explore the therapeutic effect of methyprednisolone in severe acute pancreatitis-associated lung injury model in rats.Methods Male SD rats were divided into three groups randomly:the control group,the experimental group and the intervention group.In the control group, laparotomy were performed,duodenum and pancreas were flipped only.In the experimental group,acute necrotizing pancreatitis model was induced in rats by retrograde injection of 5%sodium taurocholate into biliopancreatic duct.In the intervention group,methylprednisolone(30mg/kg)was injected into rump musle of rats after models were developed.At 6 and 12 hours after model were developed, the maximum binding capacity(Bmax)and the Kd value of PMVECβ-AR was detected in lung by means of radioactive ligand binding assay.GRK2 expression was detected in lung by means of immunofluorescence.Serum IL-6 were quantitated using ELISA kits.The severity of pancreatitis and lung injury was determined by local pathological lesion(gross and histopathologie scoring).The lung tissure water content were detected,too.The effect of methylprednisolone were observed at the same time.Results1.The lung tissure water content increased at 6 hours after SAP model induction, and more at 12 hours(P＜0.05);higher than the control group(P＜0.01).2.The Bmax of PMVECβ-AR decreased at 6 hours after SAP model induction, and more at 12 hours(P＜0.05);lower than the control group(P＜0.01).3.The Kd value of PMVECβ-AR increased at 6 hours after SAP model induction, and more at 12 hours(P＜0.05);higher than the control group(P＜0.01).4.The expression of GRK2 in lung increased at 6 hours after SAP model induction, and more at 12 hours(P＜0.05);higher than the control group(P＜0.01).5.Intervention of methylprednisolone decreased water content,GRK2 expression, IL-6 in serum,Kd value of PMVECβ-AR and increased the Bmax of PMVECβ-AR(P＜0.05);and more at 12 hours(P＜0.05).Conclusions1.Lung injury occurs at 6 hours after SAP model induction in rats,and is more severe at 12 hours.2.β-AR in pulmonary microvascular endothelial cells was lower down in severe acute pancreatitis-associated lung injury model in rats.3.GRK2 expression in lung was higher up in severe acute pancreatitis-associated lung injury model in rats,and it maybe the mechanism of the decreasion ofβ-AR in pulmonary microvascular endothelial cells.4.The intervention of methylprednisolone may attenuate the severity of acute pancreatitis-associated lung injury.更多还原