目的：探讨链脲霉素（STZ）诱导的糖尿病对大鼠骨代谢的影响及机制。材料与方法：雄性Wistar大鼠随机分成3组: 正常组（n = 6），糖尿病组（n = 5）和胰岛素治疗糖尿病组 (n = 5)。大鼠尾静脉一次性注射STZ（50 mg/kg 体重），选择空腹12 h血糖大于12 mmol/L的大鼠为本实验所需的糖尿病模型。治疗组大鼠每天在同一时间给予1.8－2.2U的胰岛素。实验周期为持续32天。采用双能X线骨吸收法（DEXA）测定股骨密度，ELISA法测定血清雄性激素睾酮水平，生化分析仪测定血清碱性磷酸酶、钙、磷浓度。结果：糖尿病大鼠的股骨密度和血清睾酮均显著低于正常组（P < 0.01），血清总碱性磷酸酶明显高于正常组和胰岛素治疗组（P < 0.01）。三组之间血钙和血磷的水平无明显差异。胰岛素治疗后糖尿病大鼠的骨密度、血清睾酮与总碱性磷酸酶得到明显的改善。结论：糖尿病严重影响骨密度，胰岛素缺乏及雄性激素降低是导致糖尿病性骨质疏松重要原因。胰岛素治疗能预防骨流失和提高血清睾酮浓度。

Objective: To investigate the effect of diabetes mellitus on bone metabolism, bone mineral density (BMD) and serum testosterone were studied in STZ-induced diabetic male rats. Materials and methods: Male Wistar rats were randomly divided into control group (n = 6), diabetic group (n = 5) and insulin-treated diabetic group (n = 5). Diabetes was intravenously induced by injection of streptozotocin (STZ, 50 mg/kg body weight), confirmed by 12 h fasting blood glucose concentration (12 mmol/L). The treatment group was subcutaneously injected with protamine zinc insulin (1.8-2.2U/animal) at the same time every day. The experiment lasted 32 days. Femoral BMD was determined by dual-energy X-ray absorptiometry (DEXA). Serum testosterone was detected by Enzyme-linked Immunosorbent Assay (ELISA) kit. Total alkaline phosphatase (ALP), calcium (Ca) and phosphorus (P) in serum were measured by bio-machine. Results: Femoral BMD in diabetic group was significantly lower than that in control (P < 0.01) but reserved by insulin treatment. Testosterone in serum was also reduced in diabetic rats (P < 0.01) and normalized by insulin treatment. Serum ALP concentration was markedly higher in diabetics (P < 0.01) compared to the controls and prevented by insulin treatment. However, no significant differences were observed in serum Ca and P among three groups. Conclusion: BMD is seriously affected by diabetes. Insulin deficiency and testosterone decrease are important causes of diabetic osteoporosis. And insulin treatment preserved bone loss and testosterone depression.