Memory reconsolidation of an inhibitory avoidance task in mice involves cytosolic ERK2 bidirectional modulation.

KRAWCZYK, MARÍA; BLAKE, MARIANO; BARATTI, CARLOS; ROMANO, ARTURO; BOCCIA, MARIANO; FELD, MARIANA

NEUROSCIENCE

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2015 vol. 294 p. 227 - 237

0306-4522

Abstract?Reconsolidation has been defined as the processof memory stabilization after retrieval involving, amongothers, gene expression regulation and post-translationalmodifications. Many of these mechanisms are shared withmemory consolidation. Here, we studied hippocampal ERKparticipation on memory reconsolidation of an inhibitoryavoidance task in CF-1 mice. We found a retrieval-inducedcytosolic ERK2 activation in the hippocampus (HIP) 15 minafter memory reactivation, and an inhibition at 45 min.PD098059, a MEK1/2 (MAPK/ERK kinase) inhibitor, administeredin the HIP immediately after retrieval impaired memoryin a dose-dependent fashion. However, infusions of thehighest dose of PD098059 performed 40 min after retrievalenhanced memory in mice trained with a weaker footshock.These results suggest for the first time that ERK2 is involvedin memory reconsolidation in a biphasic fashion.Furthermore, the inhibition of ERK could either impair orenhance mice performance depending on ERK state ofactivation.