INDUCTION OF DIABETES-MELLITUS IN SYRIAN GOLDEN-HAMSTERS USING STOREDEQUILIBRIUM SOLUTIONS OF STREPTOZOTOCIN

Streptozotocin (STZ), a compound composed of a mixture of alpha and be ta anomers, is used experimentally for the chemical induction of diabe tes mellitus in numerous animal species. It is routinely recommended t hat STZ be administered rapidly following dissolution because of its a lleged instability in solution. In the present study, we examined the effect of varying the length of time from dissolution to administratio n on the ability of STZ to induce diabetes mellitus in male Syrian gol den hamsters and examined STZ stability and state of equilibrium by hi gh-pressure liquid chromatography. Effective diabetes induction was de termined by monitoring plasma glucose concentrations 2 and 9 days afte r STZ treatment. Diabetes was successfully induced with solutions of S TZ (50 mg/kg body weight given intraperitoneally on three consecutive days) used either immediately (24-degrees-C), 2 hours (24-degrees-C), or 5 to 7 days (6-degrees-C) after dissolution in 0.1 M acetate buffer at pH 4.4 (storage temperature indicated in parentheses). Mean plasma glucose concentration was significantly higher in all STZ treatment g roups at both time points when compared with acetate buffer-treated co ntrols. There was no significant difference in plasma glucose concentr ation between STZ treatment groups. High-pressure liquid chromatograph y analysis demonstrated that the alpha- to beta- anomeric ratio of STZ had reached equilibrium in 84 minutes at 24-degrees-C and by 26 hours at 6-degrees-C following dissolution. Recovery of STZ was greater in solutions stored at 6-degrees-C than at room temperature (24-degrees-C ). Therefore, we conclude that properly stored, fully equilibrated sol utions of STZ are as effective as freshly prepared, unequilibrated STZ solution for the induction of diabetes in the Syrian golden hamster a nd are stable for long periods of time when stored at 6-degrees-C.