Changes in brain, pituitary and uterine cytoplasmic oestrogen receptors induced by oestradiol-17beta in the ovariectomized rat.
The oestrogen specific, high-affinity cytosol receptor receptor (HAR) from amygdala, anterior, middle and posterior hypothalamus, pituitary and uterus was studied in the ovariectomized rat. A single in-vivo injection of oestradiol-17beta produced significant changes in both the tissue HAR concentrations and the apparent dissociation constants (Kd) determined in vitro. Four hours after oestradiol-17beta treatment (20 mug/kg), the HAR concentration was depleted in all tissues except the posterior hypothalamus. A lower dose of oestradiol-17beta (4 mug/kg) produced similar changes in HAR concentration with the exception of those in the amygdala and posterior hypothalamus. Twenty-four hours after oestradiol-17beta, HAR concentrations had returned to pre-injection levels in all tissues except the uterus. The uterine HAR concentrations were raised after both doses of oestradiol-17beta. The apparent tissue cytosol Kd values were decreased by both doses of oestradiol-17beta. The results suggest that brain, pituitary and uterine oestrogen cytosol HARs react to plasma oestrogen in a manner predictable by the steroid receptor hypothesis. The oestradiol-17beta-induced differential effects upon the tissue cytosol concentration may contribute to the overall spectrum of action of oestrogen in the central and peripheral reproductive processes.
D000679:Amygdala / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002369:Castration; D003600:Cytosol / Q000378:metabolism; D003864:Depression, Chemical; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D007031:Hypothalamus / Q000378:metabolism; D010902:Pituitary Gland / Q000378:metabolism; D051381:Rats; D011960:Receptors, Estrogen / Q000187:drug effects* / Q000378:metabolism; D013997:Time Factors; D014599:Uterus / Q000378:metabolism*
D011960:Receptors, Estrogen; D004958:Estradiol