不同性别大鼠在2型糖尿病造模过程中的稳定性

目的研究不同性别大鼠在2型糖尿病造模过程中的成功率及模型的稳定性。方法高糖高脂饮食联合腹腔注射小剂量链脲佐菌素诱导建立雄、雌性大鼠2型糖尿病模型。成模后所有大鼠每周固定时间测血糖和体重。观察24周后，心脏穿刺取血，测定空腹血糖（FPG）、血清胰岛素（FINS）、HbA1c、甘油三脂（TG）、胆固醇（TC）、高密度脂蛋白-胆固醇（HDL-C）、低密度脂蛋白-胆固醇（LDL-C）。结果单纯高糖高脂饮食喂养，雄、雌性大鼠血糖与正常组无显著差异；STZ注射后，雄性大鼠血糖升高并逐渐平稳，而雌性需两次STZ注射，模型才比较稳定。实验结束时，雄、雌性糖尿病大鼠FPG、FINS、HOMA-IR以及TG、TC、LDL-C均显著升高，说明模型存在胰岛素抵抗和脂代谢紊乱。结论高糖高脂饲料加一次性小剂量链脲佐菌素腹腔注射，可成功建立雄性大鼠2型糖尿病模型，而同等剂量，雌性模型需两次STZ。雄、雌性糖尿病大鼠模型具有高血糖、脂质代谢紊乱和胰岛素抵抗特点。造模成功率及稳定性与性别有关，雄性大鼠较雌性大鼠成模率高，稳定性好，且耗时更短。

Observation of the Stability in Type 2 Diabetes Models of Male and Female Rats

Objective To observe the success rate of establishment of type 2 diabetes model of male and female rats and the stability of their diabetic changes. Methods Type 2 diabetic model of male and female rats was set up by feeding high-carbohydrate-high-fat diet and by intraperitoneally injecting a low-dose streptozotocin （STZ）. After successfully setting up the model, the body weight and blood glucose were assessed in all rats at fixed time each week. Blood samples were collected from the heart in all rats after 20 weeks. Fasting blood glucose, HbA1c, triglyceride, total cholesterol, HDL-C, LDL-C, fasting serum insulin were measured. Results Compared with those of the control rats, there was no difference in blood glucose between males and females by simply feeding high-glucose-high-fat diet. Blood glucose of male rats is markedly increased and stable after STZ injection only once, but increased and stable after STZ injection twice in female rats. The level of FPG, FINS, HOMA-IR, TG, TC and LDL-C were markedly increased in the male and female rats with type 2 diabetes mellitus, indicating that insulin resistance and lipid metabolic disturbance had been induced in the models. Conclusion Type 2 diabetes model of male rats, similar to human type 2 diabetes mellitus, can be induced by feeding high-glucose-high-fat diet and intraperitoneal injection of a low-dose of STZ once, but to set up a stable type 2 diabetes model of female rats needs to give STZ injection in a similar dose twice. This rat model is characterized by moderate hyperglycemia, lipid metabolic disturbance and insulin resistance. However, the successful establishment rate and stability of diabetic changes of the model are related with sex of animals. To set up the diabetic model of male rats needs a shorter time period and with a higher success rate compared with the modeling in female rats.