Participation of low-threshold Ca2+ spike in the Purkinje cells complex spike

Neuroreport. 2008 Feb 12;19(3):299-303. doi: 10.1097/WNR.0b013e3282f4cb96.

Abstract

In Purkinje cells from cerebellar slice cultures, low-threshold Ca spike (LTS) gives rise to complex bursts in the soma that resemble the complex spike induced by climbing fibers stimulation. We show that LTS is reduced by T-type and R-type Ca channel blockers (SNX-482, nickel, or mibefradil). We propose that LTS is generated by openings of T-type Ca channels (alpha-1G and/or alpha-1I subunits) and R-type Ca channels (alpha-1E subunit isoforms with a weak sensitivity to SNX-482 and to nickel). Using mibefradil we show that climbing fiber stimulation activates LTS, which contributes to the shape of the response. This Ca entry may be involved in Ca-dependent synaptic plasticity of the parallel fiber input induced by climbing fiber activation.

MeSH terms

  • Animals
  • Calcium Channel Blockers / pharmacology
  • Calcium Channels, L-Type / drug effects
  • Calcium Channels, R-Type / drug effects
  • Calcium Signaling / physiology*
  • Electrophysiology
  • Glutamic Acid / metabolism
  • Mibefradil / pharmacology
  • Nerve Fibers / physiology
  • Neuronal Plasticity / drug effects
  • Nickel / pharmacology
  • Organ Culture Techniques
  • Patch-Clamp Techniques
  • Photic Stimulation
  • Purkinje Cells / physiology*
  • Rats
  • Spider Venoms / pharmacology

Substances

  • Calcium Channel Blockers
  • Calcium Channels, L-Type
  • Calcium Channels, R-Type
  • SNX 482
  • Spider Venoms
  • Mibefradil
  • Glutamic Acid
  • Nickel