大黄素对重症急性胰腺炎大鼠小肠水通道蛋白3表达的调节作用

An experimental research on regulatory effect of traditional Chinese medicine emodin on expression of aquaporin 3 in small intestine in rats with severe acute pancreatitis

目的探讨重症急性胰腺炎（SAP）大鼠小肠水通道蛋白3（AQP3）的表达及大黄素的调节作用。方法将80只SD雄性大鼠随机分成假手术组（n=20）、模型组（n=30）、大黄素治疗组（n=30）。采用胰胆管逆行匀速注入牛磺胆酸钠（1ml／kg）方法制作SAP模型；假手术组给予等量生理盐水，大黄素组于制模后予大黄素灌胃（20mg·kg-1·d，分两次给予），模型组及假手术组给予等量生理盐水。各组分别于制模后24、72、120h处死大鼠，留取标本，采用苏木素-伊红（HE）染色、麦芽糖苷法、免疫组化法、蛋白质免疫印迹法（Western blotting）、实时定量聚合酶链反应（PCR）技术测定胰腺病理评分、血淀粉酶、AQP3蛋白及mRNA表达。结果模型组大鼠胰腺病理评分及血淀粉酶水平均较假手术组明显升高，差异均有统计学意义（均P〈0．05）；大黄素能明显降低SAP大鼠胰腺病理评分及血淀粉酶水平（均P〈0．05）。SAP大鼠回肠黏膜AQP3蛋白及mRNA表达均较假手术组明显上调，差异均有统计学意义（均P〈0．05），且以24h时更为显著；大黄素治疗可明显下调AQP3的蛋白及mRNA表达，蛋白表达于24、72、120h，mRNA表达于24h、72h与模型组比较差异均有统计学意义（均P〈0．05）。结论AQP3可能参与了SAP的病理生理改变；大黄素治疗可通过下调AQP3的蛋白及mRNA表达，明显改善SAP病情。

Objective To investigate the expression of aquaporin 3 （AQP3） in small intestine in rats with severe acute pancreatitis （SAP） and the regulatory effect of emodin on the expression. Methods Eighty male Sprague-Dawley （SD） rats were randomly divided into three groups： sham operated （SO, n=20）, SAP （n = 30）, and emodin-treated （n= 30） groups. SAP model was induced by retrograde injection of sodium taurocholate （1 ml/kg） into the biliopancreatic duct. Rats in the SO group underwent the same surgical procedure with retrograde infusion of sterile saline. After the procedure, emodin was administrated orally to rats in the emodin group （20 mg · kg-1· d-1 , half of the dose was infused once, all together twice）, the same amount of sterile saline was administrated orally in SAP and SO groups. Twenty-four, 72 and 120 hours after the induction of sodium taurocholate, rats were sacrificed and samples of blood and tissue were obtained. The pathological lesion scores of pancreas tissue, blood amylase level, the protein and mRNA expressions of AQP3 were analyzed by hematoxylin and eosin （HE） stain, diamylose, immunohistochemistry, Western blotting and real-time polymerase chain reaction （PCR） methods. Results The pathological lesion scores of pancreas tissue and the level of blood amylase were increased obviously in the rats with SAP compared with those in SO group （all P〈0.05）. Emodin could reduce the pathological lesion scores of pancreas tissue and the level of blood amylase significantly （all P〈0.05）. The up-regulation of AQP3 protein and mRNA was observed in the rat ileal mucous membrane with experimental SAP compared with that in the SO group （all P〈0.05）, especially in the time point of 24 hours. Emodin could down-regulate the expressions of AQP3 protein and mRNA at all time points, and there were statistical significant differences at 24 hours and 72 hours （all P〈0.05）. Conclusion Emodin can improve the severity of SAP obviously. AQP3 may be involved in the pathophysiological process of SAP. Emodin can down-regulate the expressions of AQP3 protein and mRNA significantly.