P2X receptors bring new structure to ligand-gated ion channels

Trends Neurosci. 1995 May;18(5):224-9. doi: 10.1016/0166-2236(95)93907-f.


P2X receptors are cation-selective ion channels that open on binding to extracellular ATP; they play a role in fast synaptic transmission between neurones, and from autonomic nerves to smooth muscles. Isolation of cDNAs that encode P2X receptors in the smooth muscle of vas deferens and in phaeochromocytoma cells indicates that the receptors are not related to other ligand-gated ion channels. Their overall structure resembles more closely that of epithelial Na+ channels and the proteins that are thought to form mechanosensitive channels in Caenorhabditis elegans. The type of P2X RNA that is found in vas deferens is expressed preferentially by apoptotic thymocytes, and the type of P2X RNA that is found in PC12 cells is abundant in the pituitary gland, suggesting hitherto unsuspected roles for ATP-gated channels in endocrine and immune function.

Publication types

  • Review

MeSH terms

  • Adenosine Triphosphate / pharmacology
  • Amino Acid Sequence
  • Animals
  • DNA, Complementary
  • Dose-Response Relationship, Drug
  • Ion Channels / metabolism*
  • Male
  • Molecular Sequence Data
  • Muscle, Smooth / metabolism*
  • PC12 Cells
  • Pituitary Gland / metabolism
  • Rats
  • Receptors, Nicotinic / genetics
  • Receptors, Purinergic P1 / drug effects
  • Receptors, Purinergic P1 / metabolism*
  • Suramin / pharmacology
  • Synaptic Transmission
  • Vas Deferens / physiology


  • DNA, Complementary
  • Ion Channels
  • Receptors, Nicotinic
  • Receptors, Purinergic P1
  • Suramin
  • Adenosine Triphosphate