title: Interaction between the basolateral amygdala and dorsal hippocampus is critical for cocaine memory reconsolidation and subsequent drug context-induced cocaine-seeking behavior in rats.
abstract: Contextual stimulus control over instrumental drug-seeking behavior relies on the reconsolidation of context-response-drug associative memories into long-term memory storage following retrieval-induced destabilization. According to previous studies, the basolateral amygdala (BLA) and dorsal hippocampus (DH) regulate cocaine-related memory reconsolidation; however, it is not known whether these brain regions interact or independently control this phenomenon. To investigate this question, rats were trained to lever press for cocaine reinforcement in a distinct environmental context followed by extinction training in a different context. Rats were then briefly re-exposed to the cocaine-paired context to destabilize cocaine-related memories, or they were exposed to an unpaired context. Immediately thereafter, the rats received unilateral microinfusions of anisomycin (ANI) into the BLA plus baclofen/muscimol (B/M) into the contralateral (BLA/DH disconnection) or ipsilateral DH, or they received contralateral or ipsilateral microinfusions of vehicle. They then remained in their home cages overnight or for 21 d, followed by additional extinction training and a test of cocaine-seeking behavior (nonreinforced active lever responding). BLA/DH disconnection following re-exposure to the cocaine-paired context, but not the unpaired context, impaired subsequent drug context-induced cocaine-seeking behavior relative to vehicle or ipsilateral ANI + B/M treatment. Prolonged home cage stay elicited a time-dependent increase, or incubation, of drug-context-induced cocaine-seeking behavior, and BLA/DH disconnection inhibited this incubation effect despite some recovery of cocaine-seeking behavior. Thus, the BLA and DH interact to regulate the reconsolidation of cocaine-related associative memories, thereby facilitating the ability of drug-paired contexts to trigger cocaine-seeking behavior and contributing to the incubation of cocaine-seeking behavior.
authors: Department of Psychology, University of North Carolina, Chapel Hill, North Carolina 27599-3270, USA.
authors: Audrey M
authors: AM
authors: Wells
authors: Heather C
authors: HC
authors: Lasseter
authors: Xiaohu
authors: X
authors: Xie
authors: Kate E
authors: KE
authors: Cowhey
authors: Andrew M
authors: AM
authors: Reittinger
authors: Rita A
authors: RA
authors: Fuchs
mesh_terms: D000679:Amygdala / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001245:Association Learning / Q000187:drug effects / Q000502:physiology*; D003042:Cocaine / Q000494:pharmacology*; D003216:Conditioning, Operant / Q000502:physiology; D058999:Drug-Seeking Behavior / Q000502:physiology*; D004777:Environment; D005108:Extinction, Psychological / Q000502:physiology; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D057567:Memory, Long-Term / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward
chemical_list: D003042:Cocaine