激活素A及其结合蛋白在STZ损伤小鼠胰腺组织中的表达及意义

目的：探讨激活素A（Act A）及其结合蛋白follistatin(FS)在小鼠胰腺损伤过程中的表达，为胰腺损伤后组织修复与重建奠定基础。方法：雄性ICR小鼠21 只，随机分为对照组（n＝6）与实验组（n＝15）。应用一次性大剂量腹腔注射链脲菌素（STZ）制备小鼠胰岛损伤模型，免疫组织化学染色法检测Act A和 FS蛋白表达， 逆转录聚合酶链反应（RT-PCR）法检测Act A和FS mRNA相对转录水平。　结果：免疫组织化学染色显示，Act A主要分布在正常小鼠胰岛细胞，腺泡细胞也有表达；FS仅表达在小鼠胰岛细胞，在腺泡细胞不表达。RT-PCR检测结果显示，Act A和FS mRNA均在正常小鼠胰腺组织表达，与对照组比较，实验组小鼠Act mRNA表达随着诱导时间的延长表达量进行性减少（P<0.01），而FS mRNA在诱导的第7天表达明显增加，第14和21天下降（P<0.01）。结论：Act A及FS主要表达在小鼠胰岛组织，在STZ诱导胰腺损伤过程中Act-FS系统表达失平衡，可能与糖尿病的发生、发展有关。

Expressions of activin A and its binding protein follistatin in pancreatic tissues of streptozotocin-induced diabetic mice and their significances

Objective To investigate the expressions of activin A (Act A) and its binding protein follistatin(FS) in mice with pancreatic injury and lay a fundation for tissue repair and reestablishment after pancreas injury.Methods Twenty one male ICR mices were randomly divided into two groups :experimental group(n=15)and control group(n= 6),Mice were treated intraperitoneally with streptozotocin (STZ) to induce pancreatic injury.The expressions of Act A and FS protein were detected by immunohistochemistry,and the expressions of activin A and follistatin mRNA were examined by RT-PCR.Results In normal mice,Act A protein mainly distributed in islet cells,and also distributed in pancreatic acinar cells;FS protein only expressed in islet cells and not in acinar cells.Act A and FS mRNA expressed in pancreatic tissues.Compared with control group,the expression of Act A mRNA in mice in experimental group decreased gradually(P<0.01),the expression of FS mRNA increased at the 7th day after injury,then decreased gradually at the 14th and 21st day (P<0.01).Conclusion Act A and its binding protein FS mainly express in mouse islet tissues.The unbalance of activin Act-FS system in streptozotocin-induced pancreatic injury may be involved in the pathogenesis of diabetes mellitus.