OBJECTIVETo explore the dynamic changes of blood sugar and body's signs in streptozotocin diabetic animal models.

METHODSRat and mouse diabetic models were established by a single intraperitoneal (ip) injection and 5-day successive ip injections of streptozotocin respectively. Blood sugar levels were measured. The food consumption index (consumption of food/body weight) and the water consumption index (consumption of water/body weight) were calculated.

RESULTSSixty five point zero percent male rats received streptozotocin, 60 mg/kg ip, developed diabetes mellitus. The blood sugar remained in high level between the 15th day and the 25th day after injection, and it began to decline afterwards. By 5-day ip injections of streptozotocin, 40 mg/kg daily, 90.0% male mice developed diabetes mellitus. Dynamic changes of blood sugar of diabetic mouse were similar to those of rats, except that the blood sugar of mice did not decline as obvious as that of rats. The changes of water consumption index were in best fit with the changes of blood sugar in both models, with correlation index r>0.970.

CONCLUSIONThe blood sugar of diabetic animal model stayed in high level from the 15th day to the 25th day after the beginning of injection. And the period is suitable for observing effect of anti-diabetic drugs. The water consumption index can reflect the blood sugar levels of diabetes animals.