Altered cocaine effects in mice lacking Ca(v)2.3 (alpha(1E)) calcium channel

Biochem Biophys Res Commun. 2002 Nov 29;299(2):299-304. doi: 10.1016/s0006-291x(02)02632-3.

Abstract

Much evidence indicates that calcium channel plays a role in cocaine-induced behavioral responses. We assessed the contributions of Ca(v)2.3 (alpha(1E)) calcium channel to cocaine effects using Ca(v)2.3 knockout mice (Ca(v)2.3-/-). Acute administration of cocaine enhanced the locomotor activity in wild-type mice (Ca(v)2.3+/+), but failed to produce any response in Ca(v)2.3-/- mice. Repeated exposure to cocaine induced the behavioral sensitization and conditioned place preference in both genotypes. Pretreatment with a D1-receptor antagonist, SCH23390, blocked the cocaine-induced place preference in Ca(v)2.3+/+ mice; however, it had no significant effect in Ca(v)2.3-/- mice. Microdialysis and RT-PCR analysis revealed that the levels of extracellular dopamine and dopamine D1 and D2 receptor mRNAs were not altered in Ca(v)2.3-/- mice. These data indicate that Ca(v)2.3 channel contributes to the locomotor-stimulating effect of cocaine, and the deletion of Ca(v)2.3 channel reveals the presence of a novel pathway leading to cocaine rewarding which is insensitive to D1 receptor antagonist.

MeSH terms

  • Animals
  • Behavior, Animal / drug effects*
  • Benzazepines / pharmacology
  • Calcium Channels / genetics
  • Calcium Channels / physiology*
  • Calcium Channels, R-Type
  • Cation Transport Proteins*
  • Cocaine / pharmacology*
  • Conditioning, Psychological
  • Dopamine / metabolism
  • Dopamine Antagonists / pharmacology
  • Kinetics
  • Mice
  • Mice, Knockout
  • Motor Activity / drug effects*
  • Neostriatum / drug effects
  • Neostriatum / metabolism
  • RNA, Messenger / biosynthesis
  • Receptors, Dopamine D1 / antagonists & inhibitors
  • Receptors, Dopamine D1 / biosynthesis
  • Receptors, Dopamine D1 / genetics
  • Receptors, Dopamine D2 / biosynthesis
  • Receptors, Dopamine D2 / genetics

Substances

  • Benzazepines
  • Cacna1e protein, mouse
  • Calcium Channels
  • Calcium Channels, R-Type
  • Cation Transport Proteins
  • Dopamine Antagonists
  • RNA, Messenger
  • Receptors, Dopamine D1
  • Receptors, Dopamine D2
  • Cocaine
  • Dopamine