Different Ca2+ Channels in Soma and Dendrites of Hippocampal Pyramidal Neurons Mediate Spike-Induced Ca2+ Influx

J Neurophysiol. 1995 Jun;73(6):2553-7. doi: 10.1152/jn.1995.73.6.2553.

Abstract

1. Intracellular recordings, in conjunction with fura-2 fluorescence imaging, were used to evaluate the contribution of the different Ca2+ channel subtypes to the Ca2+ influx induced by back-propagating trains of action potentials. High-threshold channels contributed mainly to Ca2+ influx in pyramidal cell somata and proximal dendrites, whereas low-threshold and other Ni(2+)-sensitive channels played a greater role in more distal dendritic signaling. These data suggest that the different Ca2+ channel types participate in distinct physiological functions; low-threshold channels likely play a greater role in dendritic integration, whereas high-threshold channels are more important for somatic Ca(2+)-dependent processes.

Publication types

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

MeSH terms

  • Action Potentials
  • Calcium / metabolism*
  • Calcium Channel Blockers / pharmacology*
  • Calcium Channels / drug effects
  • Calcium Channels / physiology*
  • Dendrites / physiology
  • Fura-2
  • Hippocampus / physiology*
  • Nickel / pharmacology
  • Nimodipine / pharmacology
  • Peptides / pharmacology
  • Pyramidal Cells / physiology*
  • omega-Conotoxin GVIA

Substances

  • Calcium Channel Blockers
  • Calcium Channels
  • Peptides
  • Nimodipine
  • Nickel
  • omega-Conotoxin GVIA
  • Calcium
  • Fura-2