Estrogen Binding in the Rat and Human
The interaction of estrogens with human target tissues has received scant attention as compared with other species. Early reports demonstrated that radioactive estradiol is concentrated by the human uterus in vivo (1), and is specifically bound in cytosol prepared from human endometrium (2,3,M. However, a specific cytoplasmic 8S estrogen receptor similar to that found in the rat and other species has been demonstrated in human tissues only recently by Siiteri et al. (5). The possible role of estrone in estrogen action is uncertain although several reports have shown its formation in human uterine tissue (6,7). Our interest in this problem arose from studies which demonstrated that the estrogen target organs of the human postmeno-pausal female are exposed principally to estrone rather than estradiol (8,9)• Together with similar observations made in a variety of clinical conditions which are associated with a high incidence of endometrial carcinoma, such as the polycystic ovarian syndrome, severe obesity, liver disease, and a variety of ovarian tumors, these findings indicate that exclusive production of estrone is a common endocrinologic feature of this form of neoplasia. The possibility of a causal role for estrone in the development of endometrial cancer must therefore be considered. For these reasons investigations of the interaction of the human uterine estrogen receptor system with both estradiol and estrone have been carried out.
KeywordsHuman Serum Albumin Nuclear Extract Receptor Complex Solid Circle Human Endometrium
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- 3.Notides, A., Characterization of the human uterine estrogen receptor, 53rd Meeting of the Endocrine Society, Abstract 211, San Francisco, 1971.Google Scholar
- 7.Gurpide, E., and Welch, M., Dynamics of uptake of estrogens and androgens by human endometrium, Application of a double isotope perfusion technique, J. Biol. Chem.,244:5159, 1969.Google Scholar
- 8.MacDonald, P.C., Rombaut, R.P., and Siiteri, P.K., Plasma precursors to estrogen, I. Extent of conversion ofü 4-androstene-dione to estrone in normal males and nonpregnant normal, castrate and adrenalectomized females, J. Clin. Endocrinol. Metab.,27: 1103, 1967.Google Scholar
- 9.MacDonald, P.C., Grodin, J.M., and Siiteri, P.K., The utilization of plasma androstenedione for estrone production in women. Proceedings of the Third International Congress of Endocrinology, Excerpta Medica Foundation, Amsterdam, p. 770, 1969•Google Scholar
- 10.Moriyama, I., and Siiteri, P.K., Studies on estradiol (E2) receptors in rat uterus, Fed. Proc., 31: 245, 1972.Google Scholar
- l4.Brecher, P.I., Numata, M., DeSombre, E.R., and Jensen, E.V., Conversion of uterine 4S estradiol-receptor complex to 5S complex in a soluble system, Fed. Proc, 29: 2U9, 1970.Google Scholar
- 16.Giannopoulos, G., and Gorski, J., Estrogen-binding protein of the rat uterus, different molecular forms associated with nuclear uptake of estradiol, J. Biol. Chem.,246:2530, 1971.Google Scholar
- 17.Puca, G.A., Nola, E., Sica, V., and Bresciani, F., Advances in the biosciences, Vol. VII, New York, Pergamon Press, 1971.Google Scholar
- 18.Jensen, E.V., DeSombre, E.R., Hurst, D.J., Kawashima, T., and Jungblut, P.W., Estrogen receptors in target tissues, Steroid Dynamics, New York, Acad. Press, p. 133, 1966.Google Scholar
- 19.Jensen, E.V., Jacobson, H.I., Flesher, W., Sana, N.N., Gupta, G.N., Smith, S., Cohucci, V., Shiplacoff, Neumann, H.G., DeSombre, E.R., and Jungblut, P.W., Estrogen receptors in target tissues, Steroid Dynamics, New York, Acad. Press, p. 133, 1966.Google Scholar