Differential rescue of spatial memory deficits in aged rats by L-type voltage-dependent calcium channel and ryanodine receptor antagonism

Neuroscience. 2014 Nov 7:280:10-8. doi: 10.1016/j.neuroscience.2014.09.007. Epub 2014 Sep 16.

Abstract

Age-associated memory impairments may result as a consequence of neuroinflammatory induction of intracellular calcium (Ca(+2)) dysregulation. Altered L-type voltage-dependent calcium channel (L-VDCC) and ryanodine receptor (RyR) activity may underlie age-associated learning and memory impairments. Various neuroinflammatory markers are associated with increased activity of both L-VDCCs and RyRs, and increased neuroinflammation is associated with normal aging. In vitro, pharmacological blockade of L-VDCCs and RyRs has been shown to be anti-inflammatory. Here, we examined whether pharmacological blockade of L-VDCCs or RyRs with the drugs nimodipine and dantrolene, respectively, could improve spatial memory and reduce age-associated increases in microglia activation. Dantrolene and nimodipine differentially attenuated age-associated spatial memory deficits but were not anti-inflammatory in vivo. Furthermore, RyR gene expression was inversely correlated with spatial memory, highlighting the central role of Ca(+2) dysregulation in age-associated memory deficits.

Keywords: L-type voltage-dependent calcium channel; aging; calcium; memory; microglia; ryanodine receptor.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aging / drug effects*
  • Aging / physiology
  • Animals
  • Calcium Channel Blockers / pharmacology*
  • Calcium Channels, L-Type / metabolism
  • Dantrolene / pharmacology
  • Gene Expression / drug effects
  • Hippocampus / drug effects
  • Hippocampus / physiopathology
  • Male
  • Maze Learning / drug effects
  • Maze Learning / physiology
  • Memory Disorders / drug therapy*
  • Memory Disorders / physiopathology
  • Microglia / drug effects
  • Microglia / physiology
  • Neuroimmunomodulation / drug effects
  • Neuroimmunomodulation / physiology
  • Nimodipine / pharmacology
  • Nootropic Agents / pharmacology*
  • Rats, Inbred F344
  • Ryanodine Receptor Calcium Release Channel / metabolism
  • Spatial Memory / drug effects*
  • Spatial Memory / physiology

Substances

  • Calcium Channel Blockers
  • Calcium Channels, L-Type
  • Nootropic Agents
  • Ryanodine Receptor Calcium Release Channel
  • Nimodipine
  • Dantrolene