Two distinct effects of 5-hydroxytryptamine on single cortical neurons

doi:10.1016/0006-8993(87)90861-4

Brain Research

Volume 423, Issues 1–2, 13 October 1987, Pages 347-352

https://doi.org/10.1016/0006-8993(87)90861-4 Get rights and content

Abstract

The ability of the indoleamine serotonin (5-hydroxytryptamine; 5-HT) to alter membrane characteristics of neocortical neurons was analyzed using intracellular recording techniques. The present study demonstrates that 5-HT primarily depolarized 68% of cortical neurons probably by decreasing a resting K⁺ conductance, an effect blocked by the antagonists ritanserin and cinanserin and apparently mediated by 5-HT₂ receptors. A hyperpolarization associated with an increased conductance state and insensitive to 5-HT₂ antagonists was observed in 26% of the neurons and could be mimicked by the selective 5-HT_1A agonist (±)-8-hydroxy-2-(di-N-propylamino)tetralin (8-OH-DPAT). Therefore cortical pyramidal neurons contain at least two distinct functional 5-HT receptors whose activation produces opposing effects on membrane potential and conductance.

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: This study was supported in part by the John A. Hartford Foundation, Inc., the Alfred P. Sloan Foundation, the McKnight Foundation and NIH Grants NS 23560-01 and NS 12151-12.

^*: Present address: Max Planck Institut für Psychiatrie, Abt. Klin. Neuropharmacologie, Kracpelinstr. 2, D-8000 Munich 40, F.R.G.

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Two distinct effects of 5-hydroxytryptamine on single cortical neurons

Abstract

Neuropharmacology

Neuropharmacology

Eur. J. Pharmacol.

Brain Research

Brain Research

Neuropharmacology

Eur. J. Pharmacol.

Brain Research

Biol. Psychiatry

Brain Research

Physiology and pharmacology of serotonin receptors in the rat hippocampus

Electrophysiological properties of neocortical neurons in vitro

J. Neurophysiol.