钴卟啉诱导胰岛血红素加氧酶-1过表达的初步研究

目的 探讨钴卟啉腹腔注射诱导大鼠胰岛血红素加氧酶-1(Ho-1)过表达的量/效关系及其对胰岛功能的影响.方法 大鼠分为5组,A、B、C、D 4组分别在提取胰岛前24 h予腹腔注射2.5、5、7.5及10 mg/ks的钴卟啉溶液,对照组给予1.5 Inl生理盐水.改良Goth法提取胰岛,计数胰岛得率、估定纯度,real time-PCR和Western印迹法检测胰岛组织内Ho-1mRNA及蛋白表达,糖刺激试验评价胰岛功能.结果 C、D组大鼠在注射CoPP溶液后出现机体损伤,D组部分大鼠死亡.A、B、C及对照组胰岛得率及纯度差异无统计学意义(P＞0.05),B组Ho-1mRNA及蛋白表达量为4组中最高(B组Ho-1mRNA表达量达对照组的84.18倍).A、B及对照组胰岛于低糖刺激时,胰岛素分泌量差异无统计学意义(P＞0.05),而高糖刺激下,胰岛素分泌量以B组最高,差异有统计学意义[A、B及对照组分别为:(172.37±16.4)、(187.68±19.93)及(91.25±12.64)μIU·ml-1·10islets-1·45min-1,P＜0.05].结论 腹腔注射5 mg/kg体重钴卟啉相对安全,可大幅提高大鼠胰岛组织中HO-1的表达量,并能增强胰岛功能.

CoPP induces Ho-1 upregulation in rat islet cells

Objective To investigate the effects of peritoneal injection of cobaltic protoporphyrin Ⅸ chloride(CoPP)to induce heme oxygenase-1(Ho-1)upregulation in rat islet cells.Mthods Forty rats were divided into 5 groups by management 24 h before islets isolation:group A received inlzaporitoneal injection with 2.5 ms/ks CoPP,group B with 5 ms/ks CoPP,group C with 7.5 ms/kg CoPP,and group D with 10 mg/kg CoPP.In control group NS was used instead.A modified Goth approach was used for islet isolation.the yield and purity of the islets were assessed.The expression of Ho-1 mRNA and protein were detected by real time-PCR and Western blotting respectively.Islet function was tested by glucose stimulation test.Result Severe damage was found in tlle rats in group C and D.There was no difference in islet yield and purity for group A、B、C and control(P＞0.05).Group B had the highest Ho-1 mRNA and protein expression among the 4 groups.Though there was no difference in insulin secretion by low glucose challenge for group A、B and control's islets(P＞0.05),when challenged by hish level of glucose,significant deviation was observed.The imulin secretion level was(172.37±16.4)、(187.68±19.93)and(91.25±Conclusion Peritoneal iajection of 5 mg/kg CoPP can significantly enhance the expression of Ho-1 mRNA and protein in tat islet safely and enhance the function of islet when challenged by hish concentration of glucose.