OBJECTIVETo establish and evaluate a rat model of type 2 diabetes mellitus (T2DM) associated with depression for further elaborating the disease.

METHODSTwenty-four Wistar rats were randomly divided into three groups: normal group (group N), T2DM group (group T) and T2DM with depression group (group T + D), with 8 rats in each group. The T2DM rat model was induced by high fat diet and low dose of Streptozotocin (STZ) injection, and in addition, the T2DM rats were made restraint stress for 21 days. After the model was established, the insulin tolerance test (ITT) and oral glucose tolerance test (OGTT) were performed. Then the rat depression level was analyzed by open field test, and the concentration of 5-hydroxytryptamine (5-HT) and dopamine (DA)was determined by ELISA to confirm the model identity.

RESULTSThe blood glucose level in group T and group T + D didn't return to the normal level at 180 minutes in the ITT and OGTT test; Compared with the group N, the max movement distance, retaining time in the central zone and the retaining frequency within 5 minutes in the group T + D decreased; 5-HT and DA level in the serum of rats in. group T + D was reduced.

CONCLUSIONA rat model of type 2 diabetes mellitus associated with depression has been successfully established by high fat diet and injection of low dose streptozotocin in combination with restraint stress for 21 days. This rat model is useful for further relevant studies.