[Reproductive and developmental toxicity study of prednisolone farnesylate (PNF)--teratogenicity study in rabbits by...

The effect of Prednisolone farnesylate (PNF), a newly synthesized corticosteroid, on fetal development of the rabbit was studied. PNF was administered subcutaneously at dose levels of 0(control), 0.01, 0.05 and 0.25 mg/kg/day during the fetal organogenesis period. In the pregnant animals, PNF caused no abnormalities in clinical sign, body weight gain, food consumption, or autopsy findings at 0.01 and 0.05 mg/kg/day groups; the animals at 0.25 mg/kg/day group showed a reduction in body weight gain and food consumption. Two of 13 animals at 0.25 mg/kg/day group aborted. And hydrothorax, mucosal hemorrhage of the stomach, or fading of the liver were observed in some animals. In the fetuses, PNF was observed no abnormalities in external, visceral, or skeletal examination; slight increase of embryofetal mortality, or reduction of live fetal body weight and placental weight were observed at 0.25 mg/kg/day. The results suggest that the non-effective dose level of PNF is 0.05 mg/kg/day for pregnant females in general and reproductive toxicity, and for fetuses under the condition of this study.