[Reproductive and developmental toxicity studies of FUT-187. (I)--Fertility study in rats with oral administration of...

FUT-187 was given orally at 20, 120 and 720 mg/kg during the pre-pairing period (63 days prior to pairing in males and 14 days prior to pairing in females) and the pairing period to male and female rats and in the early stage of pregnancy (days 0 through 7 of gestation) to female rats, and the effects of the test compound on male and female reproductive performance and fetal development were evaluated. One male of the 720 mg/kg group died due to treatment. Temporary salivation was observed in males and females in the 20 mg/kg or more groups. In males, increases in the weight of the pancreas in the 120 mg/kg or more groups and the adrenals in the 720 mg/kg group, a depression of body weight gain and decreases in food intake and weight of the carcass in the 720 mg/kg group were statistically significant in comparison with controls. In females, an increase in the weight of the pancreas in the 120 mg/kg or more groups, a slight depression of body weight gain during the early stage of pregnancy and a decrease in the food intake, and a decrease in the weight of the carcass in the 720 mg/kg group were statistically significant in comparison with controls. No dose-related changes were found in the estrus, copulation, insemination and fertility indices. In fetuses, decreased numbers of corpora lutea, implantation and live fetuses were observed in the 720 mg/kg group. There were no treatment-related abnormalities in fetal mortality, sex ratio, weights of fetuses and placenta, and external and visceral examinations. Based on these results, it is concluded that the no-effect-dose levels of FUT-187 are less than 20 mg/kg for the parents, 720 mg/kg for reproductive performance and 120 mg/kg for fetal development.