Cellular and network mechanisms underlying spontaneous sharp wave-ripple complexes in mouse hippocampal slices

J Physiol. 2003 Aug 1;550(Pt 3):873-87. doi: 10.1113/jphysiol.2003.044602. Epub 2003 Jun 13.


The mammalian hippocampus displays a peculiar pattern of fast (approximately 200 Hz) network oscillations superimposed on slower sharp waves. Such sharp wave-ripple complexes (SPW-R) have been implicated in memory consolidation. We have recently described a novel and unique method for studying SPW-R in naive slices of murine hippocampus. Here, we used this model to analyse network and cellular mechanisms of this type of network activity. SPW-R are usually generated within area CA3 but can also originate within the isolated CA1 region. Cellular synchronisation during SPW-R requires both excitatory and inhibitory synaptic transmission as well as electrical coupling, the latter being particularly important for the high-frequency component. Extracellular and intracellular recordings revealed a surprisingly strong inhibition of most CA1 pyramidal cells during SPW-R. A minority of active cells, however, increases action potential frequency and fires in strict synchrony with the field ripples. This strong separation between members and non-members of the network may serve to ensure a high signal-to-noise ratio in information processing during sharp wave-ripple complexes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 6-Cyano-7-nitroquinoxaline-2,3-dione / pharmacology
  • Animals
  • Electric Stimulation
  • Electroencephalography
  • Electrophysiology
  • Extracellular Space / physiology
  • GABA Antagonists / pharmacology
  • GABA-A Receptor Antagonists
  • Gap Junctions / physiology
  • Hippocampus / cytology
  • Hippocampus / physiology*
  • In Vitro Techniques
  • Mice
  • Mice, Inbred C57BL
  • Models, Neurological
  • Nerve Net / cytology
  • Nerve Net / physiology*
  • Neurons / physiology*
  • Pyramidal Cells / physiology
  • Pyridazines / pharmacology
  • Receptors, AMPA / antagonists & inhibitors
  • Synapses / physiology
  • Uncoupling Agents / pharmacology


  • GABA Antagonists
  • GABA-A Receptor Antagonists
  • Pyridazines
  • Receptors, AMPA
  • Uncoupling Agents
  • 6-Cyano-7-nitroquinoxaline-2,3-dione
  • gabazine