LeDoux Lab 2010 SfN Abstracts
 
Program#/Poster#: 914.22/MMM38
Title: Prefrontal dopamine D1 receptor expression predicts estrogen-enhanced memory for fear extinction
Location: Halls B-H
Presentation Time: Wednesday, Nov 17, 2010, 2:00 PM - 3:00 PM
Authors: *R. SHANSKY1, J. H. MORRISON1, J. E. LEDOUX2,3;
1Dept Neurosci, Mount Sinai Sch. Med., NEW YORK, NY; 2Ctr. for Neural Sci., New York Univ., New York, NY; 3Emotional Brain Inst. and the Nathan Kline Inst., Orangeburg, NY
Abstract: Women are twice as likely as men to develop stress-related mental illnesses like Major Depressive Disorder (MDD) and Post-Traumatic Stress Disorder (PTSD), the symptoms of which may reflect a disruption of the neural circuitry linking the medial prefrontal cortex (mPFC) and amygdala. We have recently reported that neurons projecting from the mPFC to the amygdala are uniquely sensitive to stress-induced morphological changes in estrogen-treated ovariectomized rats (OVX + E), while resistant to these effects in males and OVX females without estrogen replacement (OVX + veh). The present study investigated the effects of estrogen treatment on a behavioral task known to be mediated by this pathway--retrieval of fear extinction. Male, OVX + veh, and OVX + E rats underwent fear conditioning and extinction training, followed by testing for extinction retrieval. OVX + E females displayed less freezing behavior than males and OVX + veh females during the first two trials of extinction retrieval, suggesting better memory for extinction. We further asked whether performance of this task correlated with dopamine D1 receptor expression in the mPFC, as measured by immunofluorescence. D1 puncta number was positively correlated with extinction retrieval performance in OVX + E only, suggesting that estrogen may render females uniquely responsive to dopaminergic actions in the mPFC. Together, these data provide evidence that estrogen may enhance the function of the mPFC-amygdala pathway, possibly through interactions with the D1 receptor.
Support: NIMH grant MH58911