| Program#/Poster#: |
591.18/UU5 |
| Title: |
Individual differences in biochemical
modulators of fear acquisition, consolidation, and regulation |
| Location: |
Washington Convention Center: Hall A-C
|
| Presentation Time: |
Tuesday, Nov 18, 2008, 9:00 AM -10:00
AM |
| Authors: |
*K. K. COWANSAGE, D. E. A. BUSH,
E. KLANN, J. E. LEDOUX;
Ctr. Neural Sci., New York Univ., New York, NY |
| Abstract: |
Fear is an adaptive emotional response
to threatening stimuli. In such situations, memories about the experience
are acquired and consolidated in brain regions involved in implicit emotional
memory (lateral amygdala, LA), explicit memory about emotion (hippocampus,
HPC), and regulation of fear memory expression (prefrontal cortex, PFC).
In some individuals, the normal physiological expression of fear is enhanced
or prolonged, leading to pathological conditions, such as phobias and post-traumatic
stress disorder. Such conditions could reflect individual differences in
fear acquision, consolidation or regulation. Work from our lab has recently
established that outbred Sprague Dawley rats express substantial variability
in learned fear, allowing us to study individual differences in this trait
systematically. Here, we trained rats in two versions of a Pavlovian fear
conditioning paradigm (light-shock followed by tone-shock pairings in separate
contexts) to establish that fear expression is a stable phenotype within
individuals. We then anaylzed brain tissue from the LA, HPC and PFC of naive
rats to investigate region-specific biochemical differences that might contribute
to behavioral differences. Naive rats showed significant basal variability
in acetyl-histone H3, an epigenetic modification that undergoes transient
enhancement following fear conditioning. Future work will investigate corresponding
patterns in the basal expression of upstream regulators of histone acetylation,
such as phospho-CREB and phospho-ERK. We will then look at the relationship
between biochemical variability and observed phenotypic differences in fear
expression (i.e. in rats showing very high and very low levels of fear expression).
|
| Support: |
R37 MH038774 |
|
P50 MH058911 |
|
R01 MH046516 |
|
K05 MH067048 |