Autoradiography of progesterone and model compound entry and distribution in Xenopus Laevis Oocytes

The purpose of the present autoradiographic studies of oocyte-steroid interactions was two-fold. First, to examine steroid uptake for evidence of mediated entry mechanisms, several steroids and model compounds of known entry mechanism were compared in terms of kinetics, retention patterns, and perturbability of uptake. Second, patterns of intracellular steroid binding were examined for cytologic evidence of specific internal binding sites. (orig.) With 14 figs., 6 tabs