Effects of dopamine, D-1 and D-2 dopaminergic agonists on the excitability of hippocampal CA1 pyramidal cells in guinea pig

Exp Brain Res. 1990;83(1):124-30. doi: 10.1007/BF00232200.

Abstract

In hippocampal pyramidal cells (HPCs), Dopamine (DA) application (1 microM) produced, in 50% of recorded cells, an hyperpolarization of the resting membrane potential (r.m.p.) and an increase of the afterhyperpolarization (AHP) amplitude and duration in 79% of recorded cells. DA-induced effects on both the r.m.p. and AHP were mimicked by bath application of a D-1 selective agonist, SKF 38393 (20 microM). In addition, we have observed that a D-1 selective antagonist such as SCH 23390 (1 microM) abolished the action of both DA and SKF 38393. In contrast, the activation of D-2 receptors through LY 171555 (10 microns) produced, in 50% of cells, a depolarization of the r.m.p. and a depression of the AHP in 67% of recorded cells. These results suggest that the effects observed in hippocampal pyramidal neurons after DA application of micromolar concentration are mediated by D-1 subtype of receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine / pharmacology*
  • Animals
  • Dopamine / pharmacology*
  • Dopamine Agents / pharmacology*
  • Electrophysiology
  • Ergolines / pharmacology*
  • Guinea Pigs
  • Hippocampus / cytology
  • Hippocampus / drug effects
  • Hippocampus / physiology*
  • Membrane Potentials / drug effects
  • Membrane Potentials / physiology
  • Quinpirole

Substances

  • Dopamine Agents
  • Ergolines
  • Quinpirole
  • 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine
  • Dopamine