Upregulation of L-type Ca2+ channels in reactive astrocytes after brain injury, hypomyelination, and ischemia

J Neurosci. 1998 Apr 1;18(7):2321-34. doi: 10.1523/JNEUROSCI.18-07-02321.1998.

Abstract

Anti-peptide antibodies that specifically recognize the alpha1 subunit of class A-D voltage-gated Ca2+ channels and a monoclonal antibody (MANC-1) to the alpha2 subunit of L-type Ca2+ channels were used to investigate the distribution of these Ca2+ channel subtypes in neurons and glia in models of brain injury, including kainic acid-induced epilepsy in the hippocampus, mechanical and thermal lesions in the forebrain, hypomyelination in white matter, and ischemia. Immunostaining of the alpha2 subunit of L-type Ca2+ channels by the MANC-1 antibody was increased in reactive astrocytes in each of these forms of brain injury. The alpha1C subunits of class C L-type Ca2+ channels were upregulated in reactive astrocytes located in the affected regions in each of these models of brain injury, although staining for the alpha1 subunits of class D L-type, class A P/Q-type, and class B N-type Ca2+ channels did not change from patterns normally observed in control animals. In all of these models of brain injury, there was no apparent redistribution or upregulation of the voltage-gated Ca2+ channels in neurons. The upregulation of L-type Ca2+ channels in reactive astrocytes may contribute to the maintenance of ionic homeostasis in injured brain regions, enhance the release of neurotrophic agents to promote neuronal survival and differentiation, and/or enhance signaling in astrocytic networks in response to injury.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Monoclonal
  • Antibody Specificity
  • Astrocytes / chemistry
  • Astrocytes / metabolism*
  • Brain Injuries / metabolism*
  • Brain Injuries / pathology
  • Brain Ischemia / metabolism*
  • Brain Ischemia / pathology
  • Calcium Channels / analysis
  • Calcium Channels / immunology
  • Calcium Channels / metabolism*
  • Disease Models, Animal
  • Epilepsy / chemically induced
  • Epilepsy / metabolism
  • Epilepsy / pathology
  • Excitatory Amino Acid Agonists
  • Gerbillinae
  • Glial Fibrillary Acidic Protein / analysis
  • Gliosis / metabolism
  • Homeostasis / physiology
  • Hot Temperature
  • Injections, Intraventricular
  • Kainic Acid
  • Male
  • Mice
  • Mice, Neurologic Mutants
  • Myelin Sheath / pathology*
  • Rats
  • Up-Regulation / physiology
  • Wounds, Stab / metabolism
  • Wounds, Stab / pathology

Substances

  • Antibodies, Monoclonal
  • Calcium Channels
  • Excitatory Amino Acid Agonists
  • Glial Fibrillary Acidic Protein
  • Kainic Acid