胰岛素对β细胞IGF-1R表达的上调作用

The up regulatory effect of insulin on insulin-like growth factor-1 receptor expressing in beta cells

【目的】观察胰岛素对胰岛β细胞胰岛素样生长因子1受体(IGF-1R)表达的影响。【方法】胶原酶原位灌注法分离SD雄性大鼠胰岛,不连续密度梯度离心法纯化胰岛;在含100μIU/ml胰岛素的RPMI 1640培养液中分别孵育胰岛0、30、60、120、240 min,对照组是未经胰岛素孵育的胰岛,即0 min组。应用免疫组织化学方法,对胰岛β细胞以及IGF-1R进行定位,并结合激光扫描共聚焦显微镜技术对荧光图像进行半定量分析。【结果】IGF-1R定位于β细胞,对图像中β细胞表达的IGF-1R荧光积分光密度值进行分析显示,与对照组相比,胰岛素处理30 min,β细胞IGF-1R的荧光积分光密度值无显著差异(P>0.05),在胰岛素处理60、120、240 min组中,β细胞IGF-1R的荧光积分光密度值明显升高(P<0.01),并随着时间的延长,荧光密度值有上升的趋势。【结论】胰岛素对SD大鼠胰岛β细胞上IGF-1R的表达具有促进作用。

[Objective] To investigate the up-regulatory effect of insulin on insulin-like growth factor-1 receptor （IGF- 1R） expressing in beta cells. [Methods] Islets of male SD rat were isolated by the digestion of pancreas with collagenase V. Cultured primary rat islets were incubated with RPMI 1640 containong 100μIU/ml insulin for 0, 30, 60, 120 and 240 mins, respectively. Immunohistochemical and laser-scanning confocal microscopy were used to observe the expression of IGF-1R in beta cells. [Results] The expression of IGF-1R in beta cells incubated for 60, 120, 240 mins with insulin were significantly increased as compared with controls （P 〈 0.01）. And there was no change in the beta cells incubated for 30 mins （P 〉 0.05）. [Conclusions] The increased exprssion of IGF-1R in beta cells may be the effect of insulin.