1型糖尿病小鼠胰岛胰岛淀粉样多肽和生长抑素阳性细胞表达的改变

目的探讨1型糖尿病(T1DM)小鼠胰岛表达胰岛淀粉样多肽(IAPP)、生长抑素(SS)的改变及可能的机制。方法取正常C57BL/6J小鼠,小剂量多次注射链脲菌素(STZ)建立1型糖尿病小鼠模型,分别于第3、7、10、14、21、28天取胰尾组织,通过免疫组织化学SABC法、激光扫描共焦显微镜免疫荧光检测法及图像分析、形态计量法进行研究。结果 1.IAPP阳性细胞面数密度(NA)自第3天开始减少(P0.05),平均吸光度自第7天开始增高,与正常及生理盐水对照组比较差异具有显著性(P0.05);2.1型糖尿病组小鼠胰岛SS阳性细胞NA自第3天开始增加(P0.05),平均吸光度自第7天开始增高(P0.05);3.免疫荧光双染法显示,小鼠胰岛IAPP和SS在部分细胞有共表达。结论 1型糖尿病小鼠胰岛IAPP阳性细胞数目减少,表达增强;SS阳性细胞数量及表达均上调;IAPP和SS在部分细胞有共表达。提示IAPP阳性细胞和SS阳性细胞均参与了1型糖尿病的病变过程。

Expression changes of islet amyloid polypeptide,somatostatin positive cells of pancreatic islet in type 1 diabetes mellitus mice

Objective To explore the changes of the expression of islet amylodi polypeptide (IAPP) and somatostatin(SS) of islet in type 1 diabetes mice, and the mechanism of the expression changes. Methods We established the diabetes model in C57BL/6J mice by low-dose streptozotocin (STZ) injection. The excisions of the pancreas tails removed on the 3th, 7th, 10th, 14th, 21th and 28th day. Tissues were assessed by immunohistochemical SABC, immunofluorescence in the study. Results 1. Numerical density on area (N_A) of IAPP positive cells in experimental group (EG) decreased since the 3th day, but average absorbance increased since the 7th day. 2. N_A of SS-IR cells in EG increased since the 3th day, and average absorbance increased since the 7th day. 3.The results of immunofluorescence double staining showed that, IAPP and SS could coexpression in part of cells in islets. Conclusion The number of IAPP positive cells in type 1 diabetes is decreased, but the immunoreaction increased. Immunoreaction and number of SS positive cells increase. Both of them are involved in the pathogenesis of type 1 diabetes.