Study on the Optimization and Stability of Single-dose Streptozotocin-induced Diabetic Modelling in Rats

Abstract Aim: This study was performed to optimize the experimental conditions in streptozotocin (STZ)-induced diabetic model by using Sprague-Dawley (SD) rats to evaluate the stability of the model. Methods: In addition to the control group, the male and female SD rats were randomly divided into the following treatment groups (with six rats per group): STZ 45 (45 mg/kg STZ); STZ 65 (65 mg/kg STZ); STZ 85 (85 mg/kg STZ); high-fat diet with STZ 45; high-fat diet with STZ 65; and high-fat diet with STZ 85. Changes in the body weight and blood glucose were observed dynamically. Results: No significant differences were found in the blood glucose or body weight between the STZ 45 and control groups in both male and female rats, whether or not the rats were on a high-fat diet. However, significant differences were found in the blood glucose between the high-dose STZ and control groups in both male and female rats, regardless of whether the rats were on a high-fat diet or not ( P <0.05 or P <0.01). Compared with the control group, significant differences in the blood glucose levels ( P <0.05 or P <0.01) and higher blood glucose levels were found in the male rats fed with normal diet than those of rats fed with high-fat diet. Conclusions: In this study, male rats fed with ordinary feed and injected with 65 mg/kg STZ were the most stable and ideal diabetic rats.