Mechanism of prostaglandin F-2α penetration from the horn of the uterus to the ovaries in pigs

On Day 14 of the oestrous cycle PGF-2 alpha was infused into one anterior uterine vein (15 or 7.5 microgram/kg body weight) or jugular vein (15 microgram/kg) of pigs for 5 h. Progesterone levels were significantly decreased in the ipsilateral and contralateral utero-ovarian veins, the effect being greater on the side of infusion and with the higher dose. Infusion into the jugular vein did not cause luteolysis. It is suggested that the lymphatic circulation may be involved in the passage of PGF-2 alpha from one uterine horn to the contralateral ovary.