UPTAKE OF RADIOACTIVE OESTROGENS IN THE CHICKEN OVIDUCT AND SOME OTHER ORGANS

Abstract

ABSTRACT The distribution of radioactivity in the body of one week old pullets following injection of tritiated oestradiol and hexoestrol has been investigated. A few hours after the injection of either oestrogen, the oviduct had about twice the radioactivity of skeletal muscle, per unit wet weight. The uptake of hexoestrol in the oviduct showed further evidence of specificity in being depressed by the simultaneous administration of oestradiol or hexoestrol. In similar experiments oestradiol uptake in the oviduct showed no evidence of saturation. An oestrogen antagonist, MER-25, did not inhibit oestradiol uptake by the oviduct. The Bursa Fabricii showed no selective uptake. Absorption of tritiated oestradiol from a subcutaneous oil depot was inhibited by the presence in the depot of carrier oestradiol. Comparison of the results with those published by others for the mammalian uterus reveals a parallelism between the relative insensitivity of the oviduct to oestrogen stimulation and its relative weak affinity for oestrogens. There is also a parallelism between the inability of MER-25 to block oestrogen stimulated oviduct growth completely and its inability to affect oestrogen accumulation by the oviduct. In both these respects the oviduct differs from the uterus.