Streptozotocin model of stable diabetes mellitus

Aim: to create a model of stable experimental diabetes mellitus (DM) in laboratory rats using streptozotocin (STZ). Materials and methods. The dynamics of changes in glycemia and survival in 60 Wistar rats was determined. STZ at a dosage of 70 mg/kg was administered to these rats in two ways: once and fractionally (within 5 days). Results. After a single injection of the STZ, 6 out of 30 rats (20%) died, in 7 cases (23.3%) a spontaneous reversion of the diabetic status occurred and in 17 animals (56.6%) the DM remained stable throughout the observation period (8 weeks). After the fractional administration of the STZ no mortality was observed. Spontaneous reversal of DM occurred only in 2 of 30 rats (6.6% of cases). In other 28 animals hyperglycemia was stable until the end of the experiment. It is important to note that in all rats with a stable course of DM, the level of glycemia after 2 weeks after the injection of the STZ was at least 20 mmol/l. Conclusion. Fractional intraperitoneal injection of STZ has an obvious advantage compared with a single injection, providing 100% survival and stable course of DM in 93.4%. The main criterion for a stable course of experimental DM is the level of hyperglycemia not less than 20 mmol/l after 2 weeks after intraperitoneal administration of STZ.