Mouse striatal dopamine nerve terminals express alpha4alpha5beta2 and two stoichiometric forms of alpha4beta2*-nicotinic acetylcholine receptors

J Mol Neurosci. 2010 Jan;40(1-2):91-5. doi: 10.1007/s12031-009-9263-y. Epub 2009 Aug 20.


Wild-type and alpha5 null mutant mice were used to identify nicotinic cholinergic receptors (nAChRs) that mediate alpha-conotoxin MII (alpha-CtxMII)-resistant dopamine (DA) release from striatal synaptosomes. Concentration-effect curves for ACh-stimulated release (20 s) were monophasic when wild-type synaptosomes were assayed but biphasic with synaptosomes from the alpha5 null mutant. Deleting the alpha5 gene also resulted in decreased maximal ACh-stimulated alpha-CtxMII-resistant DA release. When a shorter perfusion time (5 s) was used, biphasic curves were detected in both wild-type and alpha5 null mutants, indicative of high- and low-sensitivity (HS and LS) activity. In addition, DHbetaE-sensitive (HS) and DHbetaE-resistant (LS) components were found in both genotypes. These results indicate that alpha-CtxMII-resistant DA release is mediated by alpha4alpha5beta2, (alpha4)(2)(beta2)(3) (HS), and (alpha4)(3)(beta2)(2) (LS) nAChRs.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Acetylcholine / metabolism
  • Acetylcholine / pharmacology
  • Animals
  • Conotoxins / pharmacology
  • Corpus Striatum / chemistry
  • Corpus Striatum / metabolism*
  • Dopamine / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mutation / genetics
  • Nicotinic Antagonists / pharmacology
  • Presynaptic Terminals / chemistry
  • Presynaptic Terminals / metabolism*
  • Protein Subunits / chemistry
  • Protein Subunits / genetics
  • Protein Subunits / metabolism
  • Receptors, Nicotinic / chemistry
  • Receptors, Nicotinic / genetics
  • Receptors, Nicotinic / metabolism*
  • Synaptosomes


  • Conotoxins
  • Nicotinic Antagonists
  • Protein Subunits
  • Receptors, Nicotinic
  • alpha-conotoxin MII
  • nicotinic receptor alpha4beta2
  • nicotinic receptor alpha5 subunit, mouse
  • Acetylcholine
  • Dopamine