链脲佐菌素诱导SD和Wistar大鼠糖尿病模型的影响因素

目的通过注射链脲佐菌素（STZ）制作SD和Wistar大鼠糖尿病模型,观察大鼠品系、给药剂量、给药次数对大鼠成模率、死亡率的影响,同时研究利用口服葡萄糖耐量试验（OGTT）判断大鼠糖尿病成模率的意义。方法设置共同的正常对照组,①Wistar大鼠随机分为中剂量组（55 mg/kg）和高剂量组（65 mg/kg）;②SD大鼠一次性腹腔注射STZ（55 mg/kg）,与①中的Wistar大鼠作对比;③SD大鼠随机分为一次给药组和两次给药组,注射剂量均为55 mg/kg,观察期间进行OGTT。结果①Wistar大鼠成模率和死亡率均高于SD大鼠;②采用SD大鼠、中剂量给药和两次给药的方式可提高成模率,并降低死亡率;③在有明确胰岛病理改变的模型组大鼠,其OGTT异常阳性率显著高于空腹血糖异常阳性率。结论用STZ诱导糖尿病模型是一种稳定可靠的方法。Wistar大鼠成模率和死亡率均高于SD大鼠;选用中剂量给药及两次给药的方式可提高SD大鼠成模率,并降低死亡率,维持时间较长。在动物实验中OGTT比空腹血糖监测更有诊断意义,不易造成漏诊。

Factors Affacting the Diabetic Models Induced by Streptozocin in SD and Wistar Rats

Objective To investigate the effects of streptozocin （STZ） dosage, STZ administration way and the strains of rats on the incidence and mortality of type 1 diabetes. At the same time, to study the value of oral glucose tolerance test（OGTT） for making an estimate of the incidence of diabetes mellitus. Methods ①Wistar rats were divided into high-dose groups（STZ, 65 mg/kg） and moderate-dose groups（STZ, 55 mg/kg）. ②Compare with Wistar rats, SD rats were injected intraperitoneally with moderate dose STZ （STZ, 55 mg/kg）. ③SD rats were divided into two groups. The rats in one group were in a single injection. The other group was injected twice （55 mg/kg on the first day and 55 mg/kg on the eighth day）, the OGTT was detected once in observation periods. The incidence and mortality of diabetes model were measured. Result ① The incidence and mortality of Wistar rats were higher than that of SD rats. ② Injecting twice could increase the incidence of diabetes rats and reduce the mortality. ③ The positive rate of abnormal OGTT was significantly higher than the positive rate of abnormal fasting blood glucose in the diabetic model rats whose pancreas had definite pathologic change. Conclusion The animal diabetes model induced by streptozocin is steady and reliable. The incidence and mortality of diabetes model of Wistar rats are higher than those of SD rats. Using SD rats, moderate dose STZ and injecting twice may increase the incidence of diabetes model and reduce the mortality. During animal experiment, OGTT has a better value than fasting blood glucose for making an estimate of the incidence of diabetes mellitus. Using OGTT can avoid missing diagnosis.