Steroid transfer from the ovarian vein to the ovarian artery in the sow

Abstract

The ovary and its vascular pedicle were isolated and transferred under a stereomicroscope to a heated surface (40.degree. C). The ovary was supplied with the blood from the middle uterine artery through a cannula. On different days of the estrous cycle [3H]testosterone, [3H]progesterone or [3H]estradiol-17.BETA. were infused for 30 min into the ovarian vein 1-2 cm below the ovary. During and 30 min after the infusion radioactivity was found in ovarian arterial blood and ovarian tissue. Recovery of [3H]testosterone, [3H]estradiol and [3H]progesterone infused into the ovarian vein from ovarian venous blood collected during 60 min of experiment was (mean .+-. standard error of the mean) 26.8 .+-. 6.8%, 20.1 .+-. 6.1% and 23.7 .+-. 6.2%, respectively. When 51Cr-labeled blood cells were infused in the same fashion as the steroids there was no radioactivity in arterial blood or ovarian tissue. These results indicate the existence of a countercurrent transfer mechanism and retention of the hormones in tissue(s) other than blood in the ovarian pedicle.