Venous-arterial counter-current transfer of [3H]testosterone in the vascular pedicle of the sow ovary.

[3H]Testosterone or 51Cr-labelled red blood cells were infused for 30 min through a cannula inserted into the ovarian vein below the hilus of the ovary of cyclic sows. The whole of the vascular pedicle was isolated by ligations from the systemic circulation except for the ovarian artery supplying the ovary. During and after the testosterone infusion, radioactivity was found in ovarian arterial blood and ovarian tissue, but not in peripheral blood. When 51Cr-labelled blood cells were infused in the same fashion there was no radioactivity in arterial blood or ovarian tissue. These results indicate the existence of a counter-current transfer for testosterone in the sow ovarian vascular pedicle.