title: Impairment of object recognition memory by rapamycin inhibition of mTOR in the amygdala or hippocampus around the time of learning or reactivation.
abstract: The role of the basolateral complex of the amygdala (BLA) in recognition memory remains poorly understood. The mammalian target of rapamycin (mTOR) in the BLA and other brain areas has been implicated in synaptic plasticity and memory. We have recently shown that mTOR signaling in both the BLA and the dorsal hippocampus (DH) is required for formation and reconsolidation of inhibitory avoidance, a fear-motivated memory task. Here we examined the effects of infusions of the mTOR inhibitor rapamycin into the BLA before or after either training or reactivation on retention of novel object recognition (NOR) memory in rats, and compared the effects with those obtained using intra-DH infusions. Male Wistar rats received bilateral infusions of vehicle or rapamycin into the BLA or DH before or after NOR training or reactivation. Rapamycin impaired NOR retention tested 24h after training when given either before or immediately after training into the BLA or DH. Rapamycin also impaired retention measured 24h after reactivation when infused before reactivation into the BLA or DH, or immediately after reactivation into the BLA, but not when given 6h after reactivation into either the BLA or DH. The results suggest that mTOR signaling in the BLA and DH is involved in NOR memory formation and stabilization.
authors.affiliation: Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Paulo F C
authors.initials: PF
authors.lastname: Jobim
authors.forename: Thiago R
authors.initials: TR
authors.lastname: Pedroso
authors.forename: Aline
authors.initials: A
authors.lastname: Werenicz
authors.forename: Raissa R
authors.initials: RR
authors.lastname: Christoff
authors.forename: Natasha
authors.initials: N
authors.lastname: Maurmann
authors.forename: Gustavo K
authors.initials: GK
authors.lastname: Reolon
authors.forename: Nadja
authors.initials: N
authors.lastname: Schröder
authors.forename: Rafael
authors.initials: R
authors.lastname: Roesler
mesh_terms: D000679:Amygdala / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D004791:Enzyme Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D008297:Male; D011939:Mental Recall / Q000187:drug effects / Q000502:physiology; D008845:Microinjections; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000187:drug effects* / Q000502:physiology; D012153:Retention, Psychology / Q000187:drug effects / Q000502:physiology; D020123:Sirolimus / Q000008:administration & dosage / Q000494:pharmacology*; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors / Q000502:physiology*
chemical_list: D004791:Enzyme Inhibitors; C546845:mTOR protein, rat; D058570:TOR Serine-Threonine Kinases; D020123:Sirolimus