目的探讨亨廷顿蛋白相关蛋白1(HAP1)在大鼠胰岛中的定位.方法应用一次性大剂量腹腔注射链脲佐菌素(streptozotocin)的方法选择性破坏大鼠胰岛B细胞复制糖尿病模型,免疫组织化学ABC法显示胰岛内HAP1和胰岛素免疫反应性.结果在正常大鼠胰腺内,HAP1选择性表达于胰岛内,HAP1免疫反应阳性细胞呈短条索状或团状分布在每个胰岛内,主要位于胰岛的中央部,与胰岛B细胞的分布十分相似.注射链脲佐菌素的大鼠,胰岛中含HAP1的细胞数量在注射链脲佐菌素3d后已明显减少,并随着注射后动物存活时间的延长而进一步进行性减少;在注射后4周的大鼠,胰岛中仅有少数散在分布的HAP1免疫反应弱阳性细胞.链脲佐菌素对胰岛中表达HAP1细胞的影响与对表达胰岛素细胞的影响一致.结论HAP1也存在于胰岛内,并主要定位于链脲佐菌素敏感的B细胞内.
Objective To investigate the localization of huntingtin-associated protein 1 (HAP1) in the pancreas islet of the rat. Methods To replicate rat model of diabetes through selectively destroying B cells of pancreas islet by one peritoneal injection of large dose of streptozotocin; the immunreactivities of HAP1 and insulin in the pancreas islet were showed by ABC method of immunohistochemistry. Results In the pancreas of normal rat, it was found that HAP1 expressed selectively in the islets. HAP1-containing cells were arranged as short cords or groups, mainly located in the center of each pancreas islet, having similar distributive pattern to that of pancreas islet B cell. No HAP1-immunoreactive cell was detected in the exocrine portion of the pancreas. The HAP1-containing cells in the diabetic rats decreased in number as early as 3 days after injection of streptozotocin and further progressively decreased as the rats survived longer, only a few of cells with weak HAP1-immunoreactivity remaining in the islets 4 weeks after streptozotocin injection. It was also noted that the effect of streptozotocin on the expression of HAP1 was similar to that on the expression of insulin in the islet. Conclusion HAP1 also exists in the pancreas islet, mainly located in streptozotoein-sensitive B cells.