title: The effect of exposure to charcoal and ion-exchange chromatography on the dissociation rate of estrogen from the nuclear estrogen receptor of hen oviduct.
abstract: The method of initiating dissociation of 3H-estradiol from the nuclear estrogen receptor of hen oviduct was found to have a profound effect on the dissociation rate. Likewise, prior exposure to charcoal or partial purification by ion-exchange chromatography had an effect on the dissociation rate. When the reaction was initiated by isotopic dilution with the addition of 1 microM unlabeled estradiol, dissociation of the complexes was rapid (t 1/2 approximately 3 min). When the reaction was initiated by the addition of charcoal to adsorb free steroid, the dissociation of the complexes proceeded slowly (t 1/2 approximately 30 min). Partial purification of the receptors by DEAE-Sephacel chromatography or 15 min exposure to charcoal at 0 degree C prior to initiation of the dissociation reaction by isotopic dilution produced a form of the receptor that exhibited an intermediate dissociation rate (t 1/2 approximately 10 min). The partially purified receptor that exhibited an intermediate dissociation rate was reconverted to the rapidly dissociating form in a reconstitution experiment. These data raise the possibility of a nuclear substance that regulates the rates of estrogen dissociation.
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D002606:Charcoal; D002645:Chickens; D002852:Chromatography, Ion Exchange; D004967:Estrogens / Q000378:metabolism*; D005260:Female; D007700:Kinetics; D010057:Oviducts; D011960:Receptors, Estrogen / Q000378:metabolism*
chemical_list: D004967:Estrogens; D011960:Receptors, Estrogen; D002606:Charcoal