Effects of prostaglandin F2alpha on egg transport and in vivo egg recovery from the vaginas of rabbits.

The effects of prostaglandin F2alpha (PGF2alpha) on egg transport and vaginal egg recovery were examined in rabbits. Little disturbance of egg transport was induced by an injection of 2 or 5 mg/kg of PGF2alpha 12 hours after mating. A remarkable disturbance of egg transport was seen when 5 mg/kg were injected 22 hours after mating. The administration of PGF2alpha24 hours after mating led to maximal vaginal egg recovery: 48.4% and 54.8% of eggs were recovered by 51 hours after treatment, and implantation rates were 3.2% and 6.5% after treatment with 2 and 5 mg/kg, respectively. The earliest eggs were recovered vaginally 3 hours after administration of PGF2alpha at 24, 36, 48, or 96 hours after mating. The recovery of slightly bloody washing fluids at the first and second vaginal washings in animals treated 24 or 36 hours after mating appears to indicate that severe uterine contractions were induced by PGF2alpha.