抄録
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 2.0×10-9M. 5Sprogesterone binding was inhibited competitively by cortisol. The study of ligand specificity also showed that progesterone and its related steroids had much stronger affinityfor 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.
