Fridman O, Fleming H, Gurpide E
J Steroid Biochem. 1982 May;16(5):607-12. doi: 10.1016/0022-4731(82)90094-2.
Previous reports from this laboratory have described marked changes in the levels of specific estradiol (E2) binders in cultured endometrial adenocarcinoma cells (HEC-1B) that occur during the first 30 h after replating. In the present study, binding levels were measured daily during a period of 8 days. HEC-1B cells were incubated with 100 nM [3H]-estradiol at 4 and 30 degrees C, in the presence or absence of 10 microM diethylstilbestrol and concentrations of bound ligand were determined in the nuclear and cytoplasmic fractions. It was found that concentrations of specific estradiol binders increased the first day after plating and declined thereafter. Saturation analysis of estrogen binding sites in cytosol of HEC-1B cells labeled with [3H]-E2 or [3H]-estriol (e3), at concentrations ranging from 0.1-100 mM, showed two plateaus for E2 binding (at about 20 and 60 nM) but only one (at about 40 nM) for E3, when dextran-coated charcoal was used to separate free and bound ligand. The constants of dissociation of E2 and E3 for the high affinity binder were about 4 and 20 nM, respectively.
该实验室之前的报告描述了重新接种后最初30小时内，培养的子宫内膜腺癌细胞（HEC-1B）中特定雌二醇（E2）结合物水平的显著变化。在本研究中，在8天的时间里每天测量结合水平。将HEC-1B细胞在4℃和30℃下与100 nM [3H]-雌二醇孵育，存在或不存在10 μM己烯雌酚，并在细胞核和细胞质部分中测定结合配体的浓度。发现特定雌二醇结合物的浓度在接种后的第一天增加，此后下降。用[3H]-E2或[3H]-雌三醇（E3）标记的HEC-1B细胞胞质溶胶中雌激素结合位点的饱和分析，浓度范围为0.1 - 100 mM，当使用葡聚糖包被的活性炭分离游离和结合配体时，E2结合显示两个平台（约20和60 nM），而E3仅显示一个平台（约40 nM）。E2和E3与高亲和力结合剂的解离常数分别约为4和20 nM。
