Modeling diabetic rat with erectile function

Objective To model diabetic rats with erectile dysfunction. Methods 30 Sprague-Dawley male rats were randomly divided into experimental group(n=18) and control group(n=12).The rats of experimental group were intraperitoneally injected with streptozotocin(STZ) at 60mg/kg,and the control group rats were injected with volume-mached 0.1M natrium citricum(Ph4.5).After 3d of the injection,the blood was collected from tail veins and blood glucose levels were determined.From then on,the blood glucose levels were determined for every two weeks.DM was diagnosed according to the glucose levels and symptoms of the rats.After 10wk of the injection,The body weights and intracavernous pressures(ICP) of DM rats were determined and compared with those of control group. Results(1)General conditions In the experimental group,1 rats died after 5wk because of severe DM.There were 2 rats whose glucose levels were under the creterion at 8wk and 10wk,and the rats were regarded to be resisted to STZ and excluded from the successful DM models.At last,15 of the 18 rats(regarded as DM group) were successfully modeded and the achievement ratio was 83.3%.(2)Blood glucose and body weight After STZ injection,blood glucose levels of all time points in the DM group were significantly higher than those in the control goup respectively(P0.001).There was no significant difference in the body weight between the DM and control groups before the STZ injection(P0.05),but in the 10th week after STZ injection,the body weight of DM group was significantly lower than that of control group(P0.001),the mean body weight of the DM group was 31.9% lower than that of the control group.(3)ICP In the 10th week after STZ injection,the basal ICP and neurostimulation-induced ICP of DM group(8.9±3.5 and 56.3±15.8 cmH2O) were significantly lower than those of control group(36.8±11.2 and 156.3±38.4 cmH2O)(P0.001).The decreasing rates of basal ICP and neurostimulation-induced ICP were 75.8% and 64.0%. Conclusion Modeling DM rats with STZ(60mg/kg,intraperitoneally injection) is convenient and of high achievement ratio.The basal ICP and neurostimulation-induced ICP of the model are remarkably lower than those of normal healthy rats,therefore the model is fit to be animal model for DM erectile dysfunction study.