Mechanisms of resilience after adolescent chronic stress: Implications for PTSD

COTELLA, EVELIN M.; MOLONEY, RACHEL D.; FITZGERALD, MAUREEN; MAHBOD, PARINAZ; NIBLACK, JORDAN; CHAMBERS, JAMES B.; HERMAN, JAMES P.

Chicago

Congreso; Annual Meeting Society for Neuroscience; 2019

Mechanisms of resilience after adolescent chronic stress: Implications for PTSD*E. M. COTELLA, R. D. MOLONEY, M. FITZGERALD, P. MAHBOD, J. NIBLACK, J. P. HERMAN Univ. of Cincinnati, Cincinnati, OHPosttraumatic stress disorder (PTSD) is a psychiatric condition that can develop after exposure to traumatic experience. Not everybody that experiences trauma develops the disorder, suggesting that mechanisms exist to confer resilience to some individuals but not others. Chronic stress during development is generally associated with later emergence of psychopathology, particularly under conditions of severe stress. However, mild to moderate stress during this period can also promote an adaptive response to stressful situations later in life, contributing to stress resilience. We recently demonstrated that chronic variable stress (CVS) during adolescence attenuates the impact of single prolonged stress (SPS), a potent rodent model of PTSD, on extinction and reinstatement of fear conditioning. These results suggest that stress during adolescence can evoke a resilient phenotype. In the present study, we analyzed the neuronal recruitment in the cortico-amygdalar circuitry after SPS and reinstatement in animals exposed to CVS in late adolescence. We also analyzed the expression of mRNAs associated to stress response and fear control, immediately and after 5 weeks of adolescent CVS to find possible candidates participating in the mechanism of resilience to SPS. Our results suggest that the infralimbic division (IL) of the prefrontal cortex is involved in this phenomenon. We observed a reduction of IL neuronal activation in SPS animals after reinstatement of fear (p