5-HT3 receptors in the CNS: 3B or not 3B?

Trends Pharmacol Sci. 2003 Apr;24(4):157-60. doi: 10.1016/S0165-6147(03)00051-8.


5-HT(3) receptors are widely distributed in the CNS and PNS where they participate in a variety of physiological processes. Native 5-HT(3) receptors in the CNS display functional and pharmacological heterogeneity, suggesting the existence of multiple receptor subunits. However, recent evidence suggests that of the two known subunits only the 5-HT(3A) receptor subunit (and not the 5-HT(3B) receptor subunit) is functionally present in the CNS. The molecular makeup of the 5-HT(3) receptor therefore remains an open question.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Brain / metabolism*
  • Cloning, Molecular
  • Humans
  • Organ Specificity
  • Protein Subunits / genetics
  • Protein Subunits / metabolism
  • Rats
  • Receptors, Serotonin / genetics
  • Receptors, Serotonin / metabolism*
  • Receptors, Serotonin, 5-HT3
  • Spinal Cord / metabolism*


  • Protein Subunits
  • Receptors, Serotonin
  • Receptors, Serotonin, 5-HT3