In memoriam (27 February 1927–25 December 2010).
Dissecting mechanisms of reconsolidation: octopamine reveals differences between appetitive and aversive memories in the crab Chasmagnathus
Article first published online: 7 SEP 2011
© 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd
European Journal of Neuroscience
Volume 34, Issue 7, pages 1170–1178, October 2011
How to Cite
Kaczer, L., Klappenbach, M. and Maldonado, H. (2011), Dissecting mechanisms of reconsolidation: octopamine reveals differences between appetitive and aversive memories in the crab Chasmagnathus. European Journal of Neuroscience, 34: 1170–1178. doi: 10.1111/j.1460-9568.2011.07830.x
- Issue published online: 4 OCT 2011
- Article first published online: 7 SEP 2011
- Received 11 April 2011, revised 11 July 2011, accepted 12 July 2011
- appetitive conditioning;
- aversive conditioning;
- biogenic amine;
- memory reconsolidation
Ample evidence suggests that, when reactivated by a reminder, a consolidated memory may return to a labile state and needs to be stabilized again in order to persist, a process known as reconsolidation. In a previous study, performed in the crab Chasmagnathus, we found a dual role for the biogenic amine octopamine (OA) during memory consolidation. On the one hand, it was necessary for appetitive memory formation and, on the other, it had a deleterious effect on aversive memory consolidation. Thus, OA could be a good candidate to dissect the neurochemical mechanisms of appetitive and aversive reconsolidation. Here, we initially characterized the reconsolidation of an appetitive memory. Then, we compared appetitive reconsolidation with its aversive counterpart regarding the implication of OA in these processes, and contrasted them with previous findings obtained in the consolidation phase. Our results demonstrate that appetitive reconsolidation takes place when animals are re-exposed to the training context, as shown by the amnesic effect of cycloheximide when applied before the reminder. In addition, the no-reinforcement during the reminder is a necessary condition for appetitive reconsolidation to occur. Remarkably, appetitive reconsolidation is neither impaired by OA receptor antagonists nor facilitated by exogenous OA, whereas aversive reconsolidation can be interfered with by OA administration. Thus, our results indicate that appetitive reconsolidation does not involve OA signaling, while aversive reconsolidation is negatively modulated by OA. All in all, these results could constitute a step towards the identification of particular features of appetitive and aversive reconsolidation.