【摘要】 目的 :探讨 2型糖尿病发病的机制 ,并了解 APP- 17肽、APP- 11肽、胰岛素对胰岛 β细胞凋亡率及功能的影响。方法 :将30只 2型糖尿病小鼠随机分为 4组 ,其中 3组被分别注射 APP- 17肽、APP- 11肽和胰岛素 ,另 1组未用药 ,并设 6只非糖尿病KKAY小鼠为正常对照组。 6个月后 ,用原位末端转移法 (TUNEL)对各组胰岛 β细胞进行观察 ,计算凋亡胰岛 β细胞的阳性率 ;并用放射免疫法检测胰岛素的水平。结果 :2型糖尿病小鼠未用药组胰岛 β细胞凋亡率 (5 6 .2 4± 2 .38) %显著高于正常对照组 (47.38± 3.6 5 ) % (P <0 .0 5 ) ,APP- 17肽、APP- 11肽组胰岛 β细胞的凋亡率分别为 (49.96± 2 .6 9) % ,(5 1.2 0± 2 .2 7) % ,显著低于 2型糖尿病小鼠未用药组 (P均≤ 0 .0 5 ) ;胰岛素组胰岛 β细胞的凋亡率为 (5 2 .84± 4 .5 6 ) % ,绝对值低于 2型糖尿病小鼠未用药组 ,但无统计学差异 (P >0 .0 5 )。胰岛 β细胞凋亡率在 (47.38± 3.6 5 ) %～ (5 6 .5 4± 2 .38) %时 ,所检测的胰岛素水平无显著性差异。结论 :胰岛 β细胞凋亡是 2型糖尿病的发病机制 ,APP- 17肽、APP- 11肽、胰岛素可减少胰岛 β细胞的凋亡更多还原

【Abstract】 Objective:KKAY mice is an animal model for type 2 diabetes mellitus, whose beta cell apoptosis rate in pancreatic islets were observed in order to explore the pathogenesis of type 2 diabetes mellitus,and study APP(amyoid precursor protein) 17peptide , APP 11peptide and insulin effect on them,and analyze their functions of secreting insuline Methods:30 Type 2 diabetes mellitus KKAY mices were divided into four groups at radom APP 17 peptide,APP 11 peptide and insulin were injected respectively in three groups of them,the last one served as the normal control without any injection Six months later,we examined islet beta cells by the terminal deoxynucleotidyl transferase biotin dUTP nick end labeling (TUNEL) in normal group and others groups,then calculated positive cell number of the apoptotic cells These changes were added up in groups and compared the plasma insulin concentration Results:We found that the number of islet beta cells with TUNEL positive staining were (56 24±2 38)% vs(47 38±3 65)%(P<0 05)respectively in diabetic group using nothing and in normal control.Meanwhile the apoptosis rate of islet beta cells with TUNEL positive staining in APP17 peptide group,APP11 peptide group were (49 96±2 69)%,(51 20±2 27)%,markedly reduced than the diabetic group using nothing(P≤0 05),the apoptosis rate of islet beta cells with TUNEL positive staining in insulin group was (52 84±4 56)%,the number was lower,bud statistics had no significant difference But the plasma insulin concentration had no significant difference when beta cell apoptosis rate at (47 38±3 65)%～(56 54±2 38)% Conclusion:The studies demonstrate pancreatic beta cell apoptotic mechanisms is Type 2 diabetes mellitus features;APP17 peptide,APP11 peptide and insulin could inhibit apoptosis更多还原