Progesterone receptor expression declines in the guinea pig uterus during functional progesterone withdrawal and in response to prostaglandins.

ABSTRACT: Progesterone withdrawal is essential for parturition, but the mechanism of this pivotal hormonal change is unclear in women and other mammals that give birth without a pre-labor drop in maternal progesterone levels. One possibility suggested by uterine tissue analyses and cell culture models is that progesterone receptor levels change at term decreasing the progesterone responsiveness of the myometrium, which causes progesterone withdrawal at the functional level and results in estrogen dominance enhancing uterine contractility. In this investigation we have explored whether receptor mediated functional progesterone withdrawal occurs during late pregnancy and labor in vivo. We have also determined whether prostaglandins that induce labor cause functional progesterone withdrawal by altering

SUBMITTER: Welsh TN 

PROVIDER: S-EPMC4144885 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature