Tamaya T, Nioka S, Furuta N, Shimura T, Boku S, Okada H
Endocrinol Jpn. 1977 Dec;24(6):523-8. doi: 10.1507/endocrj1954.24.523.
This study was designed to examine whether 8S protein as progesterone receptor exists in the human endometrium which has been primed with estrogen. The kinetic study showed that 8S-progesterone binding was specific with Kd of 2.0 X 10(-9) M. 5S-progesterone binding was inhibited competitively by cortisol. The study of ligand specificity also showed that progesterone and its related steroids had much stronger affinity for 8S component than for 5S component. Therefore, 5S protein may be CBG. Progesterone-8S protein binding was easily dissociated during the 5-20% sucrose gradient centrifugation, but such a protein from which progesterone had been dissociated could be sedimented at 8S region. Glycerol could stabilize progesterone-8S protein binding. These results indicate the existence of 8S protein as a progesterone receptor under the low salt medium in the estrogen primed human endometrium.
本研究旨在检测在已用雌激素预处理的人子宫内膜中是否存在作为孕激素受体的8S蛋白。动力学研究表明，8S-孕激素结合具有特异性，解离常数（Kd）为2.0×10⁻⁹M。5S-孕激素结合受到皮质醇的竞争性抑制。配体特异性研究还表明，孕激素及其相关类固醇对8S组分的亲和力比对5S组分的亲和力强得多。因此，5S蛋白可能是皮质类固醇结合球蛋白（CBG）。在5%-20%蔗糖梯度离心过程中，孕激素-8S蛋白结合很容易解离，但从其中解离出孕激素的这种蛋白可在8S区域沉降。甘油可稳定孕激素-8S蛋白结合。这些结果表明，在低盐培养基中，已用雌激素预处理的人子宫内膜中存在作为孕激素受体的8S蛋白。
