海洛因依赖对大鼠胰岛β细胞表达胰岛淀粉样多肽和葡萄糖转运蛋白2的影响

The effects of heroin dependence on expression of islet amyloid polypeptide and glucose transporter 2 in pancreas islet β cells of rats

目的探讨海洛因依赖对胰岛β细胞表达胰岛淀粉样多肽（IAPP）和葡萄糖转运蛋白2（Glut2）的影响及引起表达变化的可能机制。方法正常SD大鼠66只，随机分为正常对照组、盐水对照组及海洛因依赖组。皮下注射海洛因建立海洛因依赖大鼠模型，分别于第10、17、24、31、38天取胰尾组织。应用免疫组织化学SABC法及图像分析、形态计量法进行研究。结果1．免疫组织化学法显示，胰岛β细胞IAPP的免疫反应阳性产物定位于胞质，Glut2的免疫染色见于胞膜。2．与正常组和盐水组比较，海洛因依赖组大鼠胰岛IAPP阳性细胞免疫反应明显增强；24d以后细胞面数密度加大，与正常及盐水对照组比较有显著性差异；图像分析显示，海洛因依赖组IAPP阳性细胞的平均灰度值降低（P〈0．05），以38d时问点最低。3．海洛因依赖组大鼠Glut2阳性细胞免疫反应也明显增强；图像分析显示海洛因依赖期间大鼠胰岛Glut2阳性细胞的平均灰度值下降，与正常及盐水对照组比较差异有显著性（P〈0．05），也以38d时间点最低。结论在海洛因依赖期间，胰岛β细胞通过增加细胞数以及合成增多的方式，使IAPP和Glut2的表达增多，并参与了大鼠海洛因依赖期间机体代谢以及糖代谢的调节过程。

Objective To explore the effects of heroin dependence on expression of islet amyloid polypeptide （lAPP）and glucose transporter 2（Glut2） in islet β cells of rats, and to study the possible, mechanism of expression changes. Methods Sixty-six normal SD rats were divided into a normal control group （NCG）, a saline control group （SCG） and a heroin dependence group （HDG）. We established the heroin dependence model in rats by subcutaneous injection of heroin, and excision of the pancreas tails on 10 days, 17days, 24days, 31days and 38days. Tissues were assessed by immunohistochemical SABC, image analysis and morphometrie methods in the study. Results The results of immunohistochemical staining showed that： 1. IAPP immunoreaetion was localized in the cytoplasm of βcells, whereas Glut2 immunostaining was observed on the membranes of β cells ; 2. As compared with the NCG and SCG, the immunoreaction of IAPP immunoreacfive（IR） positive cells in HDG increased and the immunostaining of cells turned intensive, the numerical density on area also increased after the 24th day HDG （ P 〈 0.05 ）. Meanwhile, the results of image analysis showed that the mean grey degree of IAPP-IR ceils in HDG decreased as compared with NCG and SCG（ P 〈 0.05）, especially on the 38th day; 3. The immunoreaction of Glut2 positive cells in HDG increased obviously and the results of image analysis showed that the mean grey degree of Glut2-IR ceils in HDG. Decreased as compared with NCG and SCG （ P 〈 0.05）, with the lowest degree on the 38th day. Conclusion By enhancing the synthesis and secretion of IAPP and Glut2, β cells of islets are involved in the regulation of body metabolic and carbohydrate metabolic processes during heroin dependence.