Colantuoni A, Cimini V, Coppini G, Bertuglia S
CNR Institute of Clinical Physiology, University of Pisa, Italy.
Int J Microcirc Clin Exp. 1988 Mar;7(2):105-22.
Intraperitoneally injected alloxan determined long term hyperglycemia in a group of Syrian hamsters (35 hyperglycemic hamsters); transitory hyperglycemia, with recovery of normal blood glucose concentration but impairment of glucose tolerance test, was observed in a second group of alloxan-treated animals (70 normoglycemic hamsters). Microvascular permeability by fluorescent microscopy technique, capillary basement membrane thickening and pancreatic islet B, A, and D cell degranulation by computer-assisted microdensitometry were studied in Syrian hamsters at different intervals (30, 40, 60, 90, and 120 days) after intraperitoneal alloxan administration. Hyperglycemic groups showed increased permeability of venous microvasculature to high molecular weight dextran in 50%, 71.4%, and 100% of animals studied at 30, 40, and 60, 90, 120 days from treatment, respectively; indeed, they revealed pancreatic islet B cell degranulation and no capillary basement membrane thickening. Normoglycemic groups presented increased venular leakage in 28.5%, 42.8%, 71.4%, and 100% of animals investigated at 40, 60, 90, and 120 days after treatment, respectively; moreover, they showed moderate pancreatic islet B cell degranulation and no capillary basement membrane thickening. In conclusion, more severe microvascular alterations seemed to be related to more severe impairment of glucose metabolism and to longer duration of diabetes; even in normoglycemic hamsters with pathological glucose tolerance test, enhanced permeability developed.
腹腔注射四氧嘧啶可使一组叙利亚仓鼠（35只高血糖仓鼠）出现长期高血糖；在第二组接受四氧嘧啶治疗的动物（70只血糖正常的仓鼠）中观察到短暂性高血糖，血糖浓度恢复正常，但葡萄糖耐量试验受损。采用荧光显微镜技术研究叙利亚仓鼠腹腔注射四氧嘧啶后不同时间间隔（30、40、60、90和120天）的微血管通透性，通过计算机辅助显微密度测定法研究毛细血管基底膜增厚以及胰岛B、A和D细胞脱颗粒情况。高血糖组在治疗后30、40、60、90和120天分别有50%、71.4%和100%的动物出现静脉微血管对高分子量右旋糖酐的通透性增加；实际上，它们显示出胰岛B细胞脱颗粒且无毛细血管基底膜增厚。血糖正常组在治疗后40、60、90和120天分别有28.5%、42.8%、71.4%和100%的动物出现静脉渗漏增加；此外，它们表现出中度胰岛B细胞脱颗粒且无毛细血管基底膜增厚。总之，更严重的微血管改变似乎与更严重的糖代谢损害以及更长的糖尿病病程有关；即使在葡萄糖耐量试验异常的血糖正常仓鼠中，也会出现通透性增强。
