The third intracellular domain of the m3 muscarinic receptor determines coupling to calcium influx in transfected Chinese hamster ovary cells

FEBS Lett. 1996 May 13;386(1):51-4. doi: 10.1016/0014-5793(96)00398-5.


The m2 and m3 muscarinic acetylcholine receptors were expressed in CHO cells and were shown to couple to the release of calcium from intracellular stores. The m3 receptor, but not the m2 receptor, also coupled to calcium influx. Chimeric m2/m3 receptors were used to determine the structural domain of the m3 receptor linked to the regulation of calcium influx. It was found that the third intracellular loop of m3 receptor plays a fundamental role in regulating Ca2+ influx predicted to occur through Ca2+ channels located in the plasma membrane in CHO cells.

MeSH terms

  • Adenosine Triphosphate / metabolism
  • Adenosine Triphosphate / pharmacology
  • Animals
  • CHO Cells
  • Calcium / metabolism*
  • Carbachol / pharmacology
  • Cricetinae
  • DNA, Complementary / chemistry
  • DNA, Complementary / genetics
  • Muscarinic Agonists / pharmacology
  • Protein Conformation
  • Receptor, Muscarinic M3
  • Receptors, Muscarinic / chemistry
  • Receptors, Muscarinic / genetics
  • Receptors, Muscarinic / metabolism*
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / genetics
  • Recombinant Proteins / metabolism
  • Transfection


  • DNA, Complementary
  • Muscarinic Agonists
  • Receptor, Muscarinic M3
  • Receptors, Muscarinic
  • Recombinant Proteins
  • Adenosine Triphosphate
  • Carbachol
  • Calcium