title: The effect of copper in vivo on specific progesterone binding by human endometrial cytosol.
abstract: Copper has been shown to interfere with specific progesterone binding by human endometrial and myometrial cytosol in vitro. These results suggested that one possible mode of action of the copper-bearing intrauterine devices (IUDs) is through interference with the action of progesterone at its target sites. A prospective study was carried out to determine whether the proposed mode of action of copper-bearing IUDs could be demonstrated in vivo. The results of this study revealed a significant difference in specific progesterone-binding capacity between proliferative and secretory endometria (P less than 0.001). However, when secretory endometria of the controlled subjects were compared with those of the copper-bearing IUD wearers, no significant difference was observed in the specific progesterone-binding capacity (P greater than 0.2). These data suggested that copper released from copper-bearing IUDs in vivo may not interfere with the binding of progesterone to its receptors in vitro. It is doubtful that the contraceptive effectiveness of copper-bearing IUDs could be due to the ability of copper to prevent progesterone from exerting its full effects on the endometrium.
mesh_terms: D000293:Adolescent; D000328:Adult; D003600:Cytosol / Q000378:metabolism; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D006801:Humans; D007435:Intrauterine Devices, Copper; D011374:Progesterone / Q000378:metabolism*
chemical_list: D011374:Progesterone