青春期胰岛素抵抗及青春期2型糖尿病动物模型的特点

目的：分析高脂饮食诱导的青春期胰岛素抵抗大鼠及青春期2型糖尿病大鼠的特点。方法：通过正常血糖-高血浆胰岛素钳夹实验评估两种大鼠模型的胰岛素敏感性；对两种模型大鼠的雄激素与胰岛素敏感性的相关性进行研究，并与高脂饮食的成年期大鼠比较异同。结果：青春期胰岛素抵抗雄性大鼠的睾酮水平显著降低，且与胰岛素敏感性呈相关关系；小剂量链佐菌素（STZ）并不明显破坏胰岛细胞，但可使青春期胰岛素抵抗大鼠发生糖尿病（2型糖尿病）；青春期大鼠高脂饮食后仅仅甘油三酯（TG）和低密度脂蛋白胆固醇（LDL-C）升高，而成年胰岛素抵抗大鼠血脂代谢已经全面异常。结论：高脂饮食诱导的青春期大鼠胰岛素抵抗及2型糖尿病的发生可能与其血浆睾酮水平异常有关。

Characteristics of pubertal rat models with insulin resistance and type 2 diabetes mellitus

Objective:To study the characteristics of pubertal rat models with insulin resistance and type 2 diabetes mellitus. Methods:Euglycemic-hyperinsulinemic clamp technique was performed in evaluation of insulin sensitivity of two models of pubertal rats ,and the correlation between androgen of pubertal rat models and insulin sensitivity was investigated. Results: The plasma testosterone level was decreased and its concentration was positively correlated with insulin sensitivity in male rats.Islet was not obviously impaired by low-dose streptozotocin(STZ) injection (30mg/kg).But type 2 diabetes was successfully established in pubertal Wistar rats by high-fat feeding plus STZ injection .Both plasma triglycerides (TG) and plasma low-density lipoprotein (LDL-c) were increased in pubertal male rats with insulin resistance ,and dyslipidemia was aggravated in adult rats with insulin resistance. Conclusion: Our findings suggested that abnormal plasma testosterone level might play an important role in the pubertal rat by high-fat feeding with the occurrence of insulin resistance and type 2 diabetes mellitus.