大鼠胰岛细胞经门静脉肝内移植模型的建立

背景：由于肝脏既是胰岛素的作用部位，又是相对的免疫特惠区，排斥反应小，肝窦及其小静脉结构还有利于胰岛的居留和生长，可供移植容积大，有利于胰岛的生存，因此肝脏是一个较为理想的移植部位。 目的：建立一种经门静脉胰岛细胞肝内移植治疗SD大鼠1型糖尿病的动物模型。 方法：采用文献方法制备SD大鼠胰岛细胞。以腹腔注射链尿佐菌素诱导建立SD大鼠1型糖尿病模型，随机数字表法分为2组：实验组经门静脉主干穿刺输注SD大鼠胰岛1 000 胰岛当量1.5 mL；对照组经门静脉主干穿刺输注无血清1640液1.5 mL。术后未给予免疫抑制剂，观察两组大鼠出血量、血糖、胰岛素水平及肝脏组织形态学变化。 结果与结论：所有大鼠均移植成活，门静脉穿刺一次成功率90%，出血量< 0.5 mL。胰岛移植大鼠血糖降为正常的时间1~6(3.7±1.7) d，移植胰岛存活时间为2~15(8.4±4.1) d。术后2周内实验组大鼠空腹血清胰岛素水平明显高于对照组(P < 0.05，P < 0.01)。病理结果证实，移植大鼠肝细胞形态、肝小叶结构均正常，肝实质未见坏死灶，血管内无血栓形成；门静脉主干未见狭窄，亦未发生感染，说明胰岛细胞在肝窦内存活并能发挥功能。证实大鼠胰岛经门静脉主干穿刺输注肝内移植是胰岛移植基础研究的理想模型。

Intrahepatic islet transplantation through the portal vein in rats

BACKGROUND: The liver is commonly used ideal site because the liver is not only the site of insulin action, but also a relative immunologically privileged site. Furthermore, the volume of liver is big enough for transplantation; the construction of sinus hepaticus and vein is profited for dwell and growth of islet cell. OBJECTIVE: To investigate the method of intrahepatic islet transplantation through portal vein in Sprague Dawley rats with type I diabetes. METHODS: Islet cells of Sprague Dawley rats were prepared by methods of a previous study. Type I diabetes mellitus was induced with streptozotocin in Sprague Dawley rats via intraperitoneal injection. The rats were divided into two groups. 1 000 IEQ islets (1.5 mL) were infused into the liver of Sprague Dawley rats by the main portal vein puncture as experimental group, and serum-free 1640 medium (1.5 mL) was infused as control group. No immunosuppressive drug was administered after operation. Bleeding volume, blood glucose, insulin level and histomorphological changes in the liver were observed. RESULTS AND CONCLUSION: All rats survived. Success rate of portal vein puncture was 90% with bleeding volume less than 0.5 mL. Duration of normal blood glucose after operation in experimental group was 1 to 6 days (3.7 ± 1.7) days. The islet graft survival duration was 2 to 15 days (8.4 ± 4.1) days. Serum insulin levels in experimental group were significantly higher compared with control group within 2 weeks post-operative (P < 0.05, P < 0.01). The pathologic examination has confirmed that the morphous of hepatocyte and structure of hepatic lobule were normal. There was no necrosis or infection lesion in liver parenchyma and thrombopoiesis. The stenosis of main portal vein did not occur. Islet graft was pathologically viable and functioning in hepatic sinusoids. These have suggested that intrahepatic islet transplantation through the main portal vein in rats is an acceptable method.