L-type calcium channels: the low down

J Neurophysiol. 2004 Nov;92(5):2633-41. doi: 10.1152/jn.00486.2004.

Abstract

L-type calcium channels couple membrane depolarization in neurons to numerous processes including gene expression, synaptic efficacy, and cell survival. To establish the contribution of L-type calcium channels to various signaling cascades, investigators have relied on their unique pharmacological sensitivity to dihydropyridines. The traditional view of dihydropyridine-sensitive L-type calcium channels is that they are high-voltage-activating and have slow activation kinetics. These properties limit the involvement of L-type calcium channels to neuronal functions triggered by strong and sustained depolarizations. This review highlights literature, both long-standing and recent, that points to significant functional diversity among L-type calcium channels expressed in neurons and other excitable cells. Past literature contains several reports of low-voltage-activated neuronal L-type calcium channels that parallel the unique properties of recently cloned CaV1.3 L-type channels. The fast kinetics and low activation thresholds of CaV1.3 channels stand in stark contrast to criteria currently used to describe L-type calcium channels. A more accurate view of neuronal L-type calcium channels encompasses a broad range of activation thresholds and recognizes their potential contribution to signaling cascades triggered by subthreshold depolarizations.

Publication types

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

MeSH terms

  • Animals
  • Calcium Channels, L-Type / classification
  • Calcium Channels, L-Type / genetics
  • Calcium Channels, L-Type / physiology*
  • Humans
  • Neurons / physiology*

Substances

  • Calcium Channels, L-Type