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Updated: Jul 10, 2026
10:36
Systems Biology of Metabolic Regulation by Estrogen Receptor Signaling in Breast Cancer
Published on: March 17, 2016
Estrogen-receptor binding: relationship to estrogen-induced responses
Journal of Toxicology and Environmental Health
|March 1, 1976
Summary
The study shows that the amount of estrogen receptor-estrogen complex (R-E) in uterine cell nuclei changes with estrogen levels during the rat estrous cycle, suggesting physiological significance.
Area of Science:
- Endocrinology
- Molecular Biology
- Reproductive Science
Background:
- Estrogenic responses are mediated by the binding of estrogen to its receptor.
- The nuclear localization and binding of the receptor-estrogen complex (R-E) are critical steps in estrogen signaling.
Purpose of the Study:
- To investigate the relationship between nuclear binding of the receptor-estrogen complex (R-E) and estrogenic responses.
- To determine if nuclear R-E accumulation is physiologically regulated by endogenous estrogen levels.
Main Methods:
- Quantification of nuclear-bound R-E using a [3H] estradiol exchange assay.
- Measurement of R-E levels in uterine cells of rats throughout the estrous cycle.
Main Results:
- The quantity of nuclear-bound R-E was observed to fluctuate in correlation with circulating estrogen levels during the estrous cycle.
- This fluctuation indicates a dynamic process of R-E complex accumulation in the nucleus.
Conclusions:
- Nuclear accumulation of the receptor-estrogen complex (R-E) in uterine cells is physiologically significant.
- Endogenous estrogen levels appear to control the dynamic accumulation of R-E within the nucleus.
Keywords:
BiologyClinical ResearchClomipheneContraceptive Agents, EstrogenDiethylstilbestrol--analysisEndocrine SystemEstradiol--analysisEstrogensFamily PlanningFertility AgentsGenitaliaGenitalia, FemaleHormone AntagonistsHormone ReceptorsHormonesIn VitroMembrane ProteinsPhysiologyPituitary GlandReproductive Control AgentsResearch MethodologyUrogenital SystemUterusVagina
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