Potassium chloride pulse enhances mitogen-activated protein kinase activity in rat hippocampal slices

J Neurochem. 1996 Mar;66(3):1005-10. doi: 10.1046/j.1471-4159.1996.66031005.x.


Mitogen-activated protein (MAP) kinases have been implicated in multiple responses to extracellular stimuli. In this study we show that MAP kinase activity is enhanced after a KCl pulse. This activation correlates with an increased tyrosine phosphorylation of a 42-kDa protein as determined by antiphosphotyrosine immunoblot. The same band is found in an anti-MAP kinase immunoblot. Activity is enhanced within 1 min, reaches a maximum at 2 min, and returns to basal level after 10 min. A second peak of activity is observed between 12 and 30 min. The activation is completely blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), showing the involvement of the AMPA type of glutamate receptor. Partial inhibition of MAP kinase activation by 2-amino-5-phosphonovalerate (APV) also shows the involvement of the NMDA receptor. Because the KCl pulse used induces long-term potentiation (LTP) in rat hippocampal slice, we conclude that MAP kinase may be involved in neuronal transduction events leading to LTP.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2-Amino-5-phosphonovalerate / pharmacology
  • 6-Cyano-7-nitroquinoxaline-2,3-dione / pharmacology
  • Animals
  • Calcium-Calmodulin-Dependent Protein Kinases / antagonists & inhibitors
  • Calcium-Calmodulin-Dependent Protein Kinases / metabolism*
  • Enzyme Activation / drug effects
  • Hippocampus / metabolism*
  • Hippocampus / physiology
  • Immunoblotting
  • In Vitro Techniques
  • Male
  • Mitogen-Activated Protein Kinase 1
  • Phosphorylation
  • Potassium Chloride / pharmacology*
  • Protein-Tyrosine Kinases / antagonists & inhibitors
  • Protein-Tyrosine Kinases / metabolism*
  • Rats
  • Rats, Wistar
  • Tyrosine / metabolism


  • Tyrosine
  • Potassium Chloride
  • 6-Cyano-7-nitroquinoxaline-2,3-dione
  • 2-Amino-5-phosphonovalerate
  • Protein-Tyrosine Kinases
  • Calcium-Calmodulin-Dependent Protein Kinases
  • Mitogen-Activated Protein Kinase 1