Developmental potentiality of embryos cultured under low oxygen tension with superoxide dismutase.

A low-oxygen culture of preimplantation embryos with superoxide dismutase (SOD) has been demonstrated to produce a marked increase in the blastocyst formation. In this study, we examined the effects of low oxygen-SOD cultures of embryos on the potentiality of embryonic development after intrauterine transplantation and the reproductive ability of the offspring. Mouse pronuclear embryos were cultured in Biggers-Whitten-Whittingham's solution containing 0.3% bovine serum albumin and 500 micrograms/ml SOD under a low-oxygen condition (5% O2, 5% CO2, 90% N2), and 37.2% (110/296) of the embryos developed to blastocysts, with a significant difference from the 1.3% (3/231) under an atmospheric oxygen condition without SOD (P less than 0.01). The blastocysts obtained under a low oxygen-SOD culture condition were transplanted by direct insertion into the uterus of pseudopregnant females 3 days after infertile coitus. The implantation rate was 65.0% (65/100), and the embryo viability rate was 46.0% (46/100). In the control group, in which in vivo developed blastocysts were transplanted into 3-day pseudopregnant females, the implantation rate was 72.5% (81/112), and the embryo viability rate was 51.8% (58/112). The differences between the two groups were not significant. Significant differences also were not observed in either the body weight of pups at birth and 35 days after birth or the mean number of pups delivered by successive mating of the offspring between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)