Post-training reversible inactivation of hippocampus reveals interference between memory systems

Hippocampus. 2002;12(2):280-4. doi: 10.1002/hipo.10024.

Abstract

A post-training reversible lesion technique was used to examine the effects of neural inactivation of the dorsal hippocampus on place and response learning. Male Long-Evans rats trained in one of two versions of a water plus-maze task received post-training intra-hippocampal infusions of the local anesthetic drug bupivacaine (0.75% solution, 0.5 microl), or saline. Post-training intra-hippocampal infusions of bupivacaine attenuated acquisition of the place task and enhanced acquisition of the response task. Delayed (2-h) post-training infusions of bupivacaine did not affect retention in either task. The findings demonstrate (1) enhanced learning after reversible hippocampal lesions that is independent of treatment influences on non-mnemonic factors, and (2) inactivation of the dorsal hippocampus during the post-training memory consolidation period is sufficient to enhance response learning.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Analysis of Variance
  • Anesthetics, Local / pharmacology
  • Animals
  • Bupivacaine / pharmacology
  • Conditioning, Psychological / drug effects
  • Conditioning, Psychological / physiology*
  • Hippocampus / physiology*
  • Male
  • Maze Learning / drug effects
  • Maze Learning / physiology
  • Memory / drug effects
  • Memory / physiology*
  • Microinjections
  • Rats
  • Rats, Long-Evans

Substances

  • Anesthetics, Local
  • Bupivacaine