Preimplantation development in the streptozotocin-induced diabetic mouse.

Streptozotocin (STZ) was used to develop a diabetic mouse model in which to study the development of the preimplantation embryo. STZ doses of 0, 160, 190, 210 and 240 mg kg-1 were given; 190 mg kg-1 was found to be the most suitable as the standard diabetogenic dose, providing about 60% mice with plasma glucose greater than 20 mM. The STZ-diabetic mice responded to superovulation with 10 i.u. of gonadotrophin in the same manner as control mice, producing similar embryo numbers at 48 h, 72 h and 96 h post-hCG. Furthermore, the proportion of 2-cell embryos collected from STZ-diabetic mice which developed to blastocysts in vitro was similar to that of 2-cell embryos from control mice. The STZ-diabetic mouse model after superovulation thus produced normal early preimplantation embryos whose development can be examined in detail in a diabetic environment.