Time-dependent involvement of PKA/PKC in contextual memory consolidation

Behav Brain Res. 2002 Jul 18;133(2):159-64. doi: 10.1016/s0166-4328(01)00476-4.

Abstract

Rats were implanted bilaterally with cannulae into the dorsal hippocampus and trained in a Pavlovian fear-conditioning paradigm. Four groups of rats were infused intra-cranially with 1-(5'-isoquinolinesulfonyl)-2-methylpiperazine (H7-dihydrochloride), a potent inhibitor of both protein kinase C (PKC) and cAMP-dependent protein kinase (PKA), at different time intervals in order to examine their involvement in the acquisition and consolidation of contextual fear memory. We demonstrate a significant consolidation deficit of long-term contextual fear-conditioning memory that is maximal when PKA and PKC are inhibited at 90 min post-training. These results suggest the existence of a critical time window, during which these enzymes must be activated for the consolidation of long-term memories.

Publication types

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

MeSH terms

  • 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine / pharmacology
  • Animals
  • Conditioning, Psychological / drug effects
  • Conditioning, Psychological / physiology
  • Cyclic AMP-Dependent Protein Kinases / antagonists & inhibitors*
  • Enzyme Inhibitors / pharmacology*
  • Fear / drug effects
  • Fear / physiology
  • Hippocampus / anatomy & histology
  • Hippocampus / drug effects
  • Hippocampus / enzymology
  • Long-Term Potentiation / drug effects
  • Male
  • Memory / drug effects
  • Memory / physiology*
  • Protein Kinase C / antagonists & inhibitors*
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Enzyme Inhibitors
  • 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine
  • Cyclic AMP-Dependent Protein Kinases
  • Protein Kinase C