Partial prevention of tritium induced uterine involution in mice by 2-mercaptopropionylglycine.

Pregnant Swiss albino mice were given on day 11.25 post conception a priming intraperitoneal (i.p.) injection of tritiated water at the activity levels 37, 74 or 185 kBq/ml body water, in the absence (control) or presence (experimental) of 2-mercaptopropionylglycine (MPG), 20 mg/kg body weight, given intraperitoneally 30 minutes before the tritium administration. The females were subsequently maintained on tritiated drinking water until term, at the above activity level, in the control series. The animals of the experimental series received in addition a daily i.p. injection of MPG at the same time of the day, until term. A third series received a daily injection of the drug, but no tritium, at the same dose rate. None of the females from the control series had parturition, and a gradual decline in their weight was recorded, exhibiting resorption. Treatment with MPG led to an obvious increase in embryonic survival in all groups, and even in the 185 kBq group two-thirds of the females had parturition.