Inhibition of mTOR by rapamycin in the amygdala or hippocampus impairs formation and reconsolidation of inhibitory avoidance memory.
Mammalian target of rapamycin (mTOR), a central regulator of protein synthesis in neurons, has been implicated in synaptic plasticity and memory. Here we show that mTOR inhibition by rapamycin in the basolateral amygdala (BLA) or dorsal hippocampus (DH) impairs both formation and reconsolidation of memory for inhibitory avoidance (IA) in rats. Male Wistar rats received bilateral infusions of vehicle or rapamycin into the BLA or DH before or after IA training or retrieval. Memory retention was tested at different time points after drug infusion. Rapamycin impaired long-term IA retention when given before or immediately after training or retrieval into the BLA. When infused into the DH, rapamycin produced memory impairment when given before training or immediately after retrieval. The impairing effects of post-retrieval rapamycin required memory retrieval and were not reversed by a reminder shock. The results provide the first evidence that mTOR in the BLA and DH might play a role in IA memory reconsolidation.
Laboratory of Neuropharmacology and Neural Tumor Biology, Department of Pharmacology, Institute for Basic Health Sciences, Federal University of Rio Grande do Sul, 90050-170 Porto Alegre, RS, Brazil.
Paulo F C
PF
Jobim
Thiago R
TR
Pedroso
Raissa R
RR
Christoff
Aline
A
Werenicz
Natasha
N
Maurmann
Gustavo K
GK
Reolon
Rafael
R
Roesler
D000679:Amygdala / Q000187:drug effects*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D004597:Electroshock; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D008568:Memory / Q000187:drug effects*; D009474:Neurons / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D012153:Retention, Psychology / Q000187:drug effects / Q000502:physiology; D020123:Sirolimus / Q000494:pharmacology*; D058570:TOR Serine-Threonine Kinases / Q000037:antagonists & inhibitors*
D058570:TOR Serine-Threonine Kinases; D020123:Sirolimus