Identification of Calcineurin as a Key Signal in the Extinction of Fear Memory

摘要: Memory extinction refers to a gradual decrease of the previously acquired response when exposed conditional stimulus without pairing with unconditional stimulus. Here we show for first time that fear training-induced phosphorylation specific substrates in rat amygdala is reduced after trials and accompanied by an increase protein level enzymatic activity calcineurin. In parallel, calcineurin inhibitors prevented extinction-induced dephosphorylation as well memory. Thus, training increased phosphatase likely via expression Calcineurin then created negative-feedback loop directly or indirectly dephosphorylated substrates, which, their phosphorylated state, were required memory consolidation. Accordingly, our experimental condition, could be ascribed at least part weakening original signaling.