Komai T, Eckelman W C, Johnsonbaugh R E, Mazaitis A, Kubota H, Reba R C
J Nucl Med. 1977 Apr;18(4):360-6.
Four radioiodinated estrogen derivatives were studied to determine their affinity for the estrogen-binding protein found in the cytosol of rabbit and rat uteri. In vitro determination of the binding properties by competitive-binding experiments and by sucrose-gradient centrifugation indicates that one of the derivatives, iodohexestrol, binds to the cytosol estrogen-binding protein. This in vitro behavior was related to in vivo distribution. Studies in immature female rats showed high uterine uptake of iodohexestrol at 2 hr (1.69% dose/gm). Iodohexestrol also has a high nonspecific binding in both the blood and the uterine cytosol. Thyroxine can diminish the nonspecific binding in vitro; in vivo the prior injection of thyroxine increased the 2-hr uterus-to-blood ratio from 1.9 to 10.4 The in vitro receptor-assay system was helpful in predicting in vivo distribution.
研究了四种放射性碘化雌激素衍生物，以确定它们与兔和大鼠子宫胞质溶胶中发现的雌激素结合蛋白的亲和力。通过竞争性结合实验和蔗糖梯度离心法对结合特性进行体外测定，结果表明其中一种衍生物碘己雌酚能与胞质溶胶雌激素结合蛋白结合。这种体外行为与体内分布有关。对未成熟雌性大鼠的研究表明，碘己雌酚在2小时时子宫摄取量很高（1.69%剂量/克）。碘己雌酚在血液和子宫胞质溶胶中也有很高的非特异性结合。甲状腺素可在体外减少非特异性结合；在体内，预先注射甲状腺素可使2小时时子宫与血液的比值从1.9提高到10.4。体外受体测定系统有助于预测体内分布。
