Hippocampal α7-nicotinic cholinergic receptors modulate memory reconsolidation: a potential strategy for recovery from amnesia

BLAKE, MG; BOCCIA, MM; KRAWCZYK, MC; BARATTI, CM

NEUROBIOLOGY OF LEARNING AND MEMORY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Lugar: Amsterdam; Año: 2013

1074-7427

When subjects are exposed to new learning experiences, the novel information could be acquired and 28 eventually stored through memory consolidation process. The exposure of mice to a novel experience 29 (a hole-board) after being trained in an inhibitory avoidance apparatus is followed by impaired perfor- 30 mance of the avoidance memory in subsequent tests. The same impairing effect is produced when mice 31 are exposed to the novel environment after the reactivation of the avoidance memory. This interfering 32 effect is due to impaired consolidation or reconsolidation of the avoidance memory. The administration 33 of the a7-nicotinic receptor agonist choline (Ch) in the dorsal hippocampus (0.8 lg/hippocampus) imme- 34 diately after the inhibitory avoidance memory reactivation, allowed memory recovery. This effect of Ch 35 was time-dependent, and retention performance was not affected in drug-treated mice that were not 36 subjected to memory reactivation, suggesting that the effects on performance are not due to non-specific 37 effects of the drug. The effects of Ch also depended on the age of the reactivated memory. Altogether, our 38 results suggest that Ch exerts its effects by modulating memory reconsolidation, and that the memory 39 impairment induced by new learning is a memory expression failure and not a storage deficit. Therefore, 40 reconsolidation, among other functions, might serve to change whether a memory will be expressed in 41 later tests. Summarizing, our results open new avenues about the behavioral significance and the phys- 42 iological functions of memory reconsolidation, providing new strategies for recovering memories from 43 some types of amnesia.