Utero-ovarian venous concentrations of prostaglandin E2 (PGE2) and prostaglandin F2 alpha (PGF2 alpha) following PGE2 intrauterine infusions.

The uterine horns and utero-ovarian veins of nine crossbred mature gilts were bilaterally cannulated on day 9 of the estrous cycle (day O - first day of estrus). Each uterine horn in treated gilts (N = 5) was infused with 150 micrograms PGE2 in 3 ml of saline at 0900 h on day 12, 15 and 18 of the estrous cycle. Control gilts (N = 4) received 3 ml saline intrauterine infusions on the corresponding day. Blood samples were collected from the utero-ovarian veins 15 min before each infusion and for the following 6 h with 15, 30 and 60 min intervals through the first, second and third two-hour periods, respectively. Venous concentrations of PGE2 and PGF2 alpha were determined by radioimmunoassay procedures. Infusion of PGE2 resulted in an immediate elevation in PGE2 concentration in utero-ovarian venous drainage. Coincident elevations of PGF2 alpha utero-ovarian venous concentrations were observed after PGE2 infusion. Plasma PGF2 alpha concentrations in the utero-ovarian veins were elevated (P less than .01) in PGE2 treated gilts for one hour post-treatment. The duration of PGE2 and PGF2 alpha elevations as well as the peak values were influenced by day of the cycle.