A decline in the levels of progesterone receptor coactivators in the pregnant uterus at term may antagonize progesterone receptor function and contribute to the initiation of parturition.

ABSTRACT: The molecular events that lead to the onset of labor in humans and in other mammalian species remain unclear. We propose that a decline in coactivators containing histone acetylase activity in myometrium may contribute to the onset of labor by impairing the function of the progesterone-progesterone receptor (PR) complex. As assessed by semiquantitative and real-time RT-PCR, immunohistochemistry, and immunoblotting, expression of the PR coactivators cAMP-response element-binding protein (CREB)-binding protein and steroid receptor coactivators 2 and 3 was decreased in fundal uterine tissue of women in labor. Using the mouse as an animal model, we also found decreased coactivator levels in uterine tissues at term. In both human and mouse, the levels of acetylated histone H3 were also decrease

SUBMITTER: Condon JC 

PROVIDER: S-EPMC170950 | biostudies-literature | 2003 Aug

REPOSITORIES: biostudies-literature