The basolateral nucleus of the amygdala is necessary to induce the opposing effects of stressful experience on learning in males and females.
The basolateral nucleus of the amygdala (BLA) has been implicated in the modulation of learning after stress. Acute inescapable stress enhances classical eyeblink conditioning in male rats, whereas the same stressor impairs eyeblink conditioning in female rats. The experiments here directly assessed whether inactivation of the BLA during stress exposure would block both the stress-induced facilitation in males and the retardation of eyeblink conditioning in females. To this end, the BLA was temporarily inactivated by infusion of the GABA agonist muscimol before acute stressor exposure. All rats were trained in a different context 24 h later. Males infused with muscimol before the stressful event did not exhibit facilitated eyeblink conditioning, whereas those infused with the vehicle emitted more conditioned responses than unstressed males. Females infused with muscimol before stress did not express a deficit in conditioning, whereas those infused with vehicle and stressed emitted fewer conditioned responses than unstressed vehicle controls. These data demonstrate that neuronal activity within the BLA during stress exposure is necessary to modulate learning 24 h later in a new context. Thus, the BLA is necessary to induce the long-term effect of stressful experience on conditioning regardless of sex and direction of modulation.
Waddell
Jaylyn
J
Department of Psychology and Center for Collaborative Neuroscience, Rutgers University, Piscataway, New Jersey 08854, USA.
Bangasser
Debra A
DA
Shors
Tracey J
TJ
D000679:Amygdala / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D003215:Conditioning, Eyelid / Q000187:drug effects / Q000502:physiology; D005260:Female; D018755:GABA Agonists / Q000494:pharmacology; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D007859:Learning Disabilities / Q000503:physiopathology*; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D009118:Muscimol / Q000494:pharmacology; D051381:Rats; D012727:Sex Characteristics; D013315:Stress, Psychological / Q000503:physiopathology*; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D018755:GABA Agonists; D009118:Muscimol; D005680:gamma-Aminobutyric Acid