Anisomycin infused into the hippocampus fails to block "reconsolidation" but impairs extinction: the role of re-exposure duration.

Abstract

Recent studies have reported new evidence consistent with the hypothesis that reactivating a memory by re-exposure to a training context destabilizes the memory and induces "reconsolidation." In the present experiments, rats' memory for inhibitory avoidance (IA) training was tested 6 h (Test 1), 2 d (Test 2), and 6 d (Test 3) after training. On Test 1 the rats were either removed from the shock compartment immediately after entry or retained in the shock context for 200 sec, and intrahippocampal infusions of the protein synthesis inhibitor anisomycin (75 microg/side) were administered immediately after the test. Anisomycin infusions administered after Test 1 impaired IA performance on Test 2 in animals given the brief re-exposure, but impaired extinction in animals exposed to the context for 200 sec. Rats with anisomycin-induced retention impairment on Test 2 demonstrated spontaneous recovery of retention performance on Test 3, whereas rats showing extinction on Test 2 showed further extinction on Test 3. The findings indicate that post-retrieval administration of anisomycin impairs subsequent retention performance only in the absence of extinction and that this impairment is temporary.

• Authors: Ann E Power, Daniel J Berlau, James L McGaugh, Oswald Steward
• Journal: Learning & memory (Cold Spring Harbor, N.Y.) (Learn Mem) 2006 Jan-Feb Vol. 13 Issue 1 Pg. 27-34 ISSN: 1072-0502 [Print] United States
• PMID: 16452651 (Publication Type: Comparative Study, Journal Article, Research Support, N.I.H., Extramural)

Chemical References

• Protein Synthesis Inhibitors
• Anisomycin

Topics

• Animals
• Anisomycin (administration & dosage)
• Avoidance Learning (drug effects)
• Conditioning, Classical (drug effects)
• Drug Administration Schedule
• Extinction, Psychological (drug effects)
• Hippocampus (drug effects)
• Male
• Mental Recall (drug effects)
• Protein Synthesis Inhibitors (administration & dosage)
• Rats
• Rats, Sprague-Dawley