5-HT2A receptor or alpha1-adrenoceptor activation induces excitatory postsynaptic currents in layer V pyramidal cells of the medial prefrontal cortex

Eur J Pharmacol. 1999 Feb 19;367(2-3):197-206. doi: 10.1016/s0014-2999(98)00945-5.

Abstract

We compared 5-hydroxytryptamine (5-HT), norepinephrine and dopamine for their efficacy at increasing excitatory postsynaptic current frequency in layer V pyramidal cells from rat medial prefrontal cortical slices. 5-HT, norepinephrine and dopamine increased the excitatory postsynaptic current frequency by 15.9-, 4.5- and 1.7-fold, respectively. Similar to previous results with 5-HT-induced excitatory postsynaptic currents, blockade of mu-opioid receptors, of alpha-amino-3-hydroxy-5-methylisoxazole-4-proprionic acid (AMPA) receptors and fast Na+ channels suppressed the norepinephrine-induced excitatory postsynaptic currents. The norepinephrine-induced, and in most cases, the dopamine-induced increase in excitatory postsynaptic current frequency was blocked by the alpha1-adrenoceptor antagonist prazosin while the alpha2-adrenoceptor antagonist yohimbine did not block either the norepinephrine- or the 5-HT-induced increase in excitatory postsynaptic currents frequency. The potency of three 5-HT2 receptor antagonists with varying selectivity for 5-HT2A/2B/2C receptors tested against the 5-HT-induced increase in excitatory postsynaptic current frequency are in agreement with the affinity of these drugs for the 5-HT2A receptor. These findings suggest that 5-HT2A receptor or alpha1-adrenoceptor activation enhance neurotransmitter release from a similar subset of glutamate terminals that innervate apical dendrites of layer V pyramidal cells.

Publication types

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

MeSH terms

  • Animals
  • Biogenic Monoamines / pharmacology*
  • Dopamine / pharmacology
  • Excitatory Postsynaptic Potentials / drug effects*
  • In Vitro Techniques
  • Male
  • Norepinephrine / pharmacology
  • Prazosin / pharmacology
  • Prefrontal Cortex / drug effects*
  • Pyramidal Cells / drug effects*
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, AMPA / antagonists & inhibitors
  • Receptors, Adrenergic, alpha-1 / physiology*
  • Receptors, Opioid, mu / antagonists & inhibitors
  • Receptors, Serotonin / classification
  • Receptors, Serotonin / physiology*
  • Serotonin / pharmacology
  • Sodium Channel Blockers
  • Yohimbine / pharmacology

Substances

  • Biogenic Monoamines
  • Receptors, AMPA
  • Receptors, Adrenergic, alpha-1
  • Receptors, Opioid, mu
  • Receptors, Serotonin
  • Sodium Channel Blockers
  • Yohimbine
  • Serotonin
  • Dopamine
  • Norepinephrine
  • Prazosin