Estradiol and Progesterone have Opposing Roles in the Regulation of Fear Extinction in Female Rats.

ABSTRACT: Fear extinction, the laboratory basis of exposure therapy for anxiety disorders, fluctuates across the female rat estrous cycle, where extinction is enhanced during proestrus (high estradiol and progesterone), and impaired during metestrus (low estradiol and progesterone). During the estrous cycle increasing levels of estradiol precede and then overlap with increased levels of progesterone. We sought to isolate the impact of these hormonal changes on fear extinction by systematically treating ovariectomized female rats with estradiol alone, or in combination with progesterone. We found that estradiol alone facilitated extinction recall, whereas the effects of progesterone on estradiol-treated rats were biphasic and dependent on the time interval between progesterone administration and exti

SUBMITTER: Graham BM 

PROVIDER: S-EPMC4707823 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature