5-Carboxyamidotryptamine mimics only the 5-HT elicited hyperpolarization of hippocampal pyramidal cells via 5-HT1A receptor

Neurosci Lett. 1989 Apr 24;99(1-2):101-6. doi: 10.1016/0304-3940(89)90272-3.


Perfusion of the rat hippocampal slice in vitro by 5-hydroxytryptamine (5-HT) elicits 3 distinct actions recorded intracellularly from pyramidal cells in area CA1: a hyperpolarization, reduction in spike train elicited afterhyperpolarization (AHP) and depolarization. 5-Carboxyaminotryptamine (5-CT) mimics the membrane hyperpolarization elicited by 5-HT through its action on the 5-HT1A receptor; however, 5-CT does not mimic 5-HT in reducing the amplitude of the AHP or the depolarization of membrane potential. The hyperpolarizing effect of 5-CT is blocked by spiperone. These data provide evidence that the inhibitory effect of 5-HT is mediated primarily by the 5-HT1A receptor.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Action Potentials / drug effects
  • Animals
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Hippocampus / physiology*
  • In Vitro Techniques
  • Membrane Potentials / drug effects
  • Rats
  • Receptors, Serotonin / drug effects
  • Receptors, Serotonin / physiology*
  • Serotonin / analogs & derivatives*
  • Serotonin / pharmacology*


  • Receptors, Serotonin
  • Serotonin
  • 5-carboxamidotryptamine