Nicotine suppression of gustatory responses of neurons in the nucleus of the solitary tract

Christopher T. Simons, Yves Boucher, Mirela Iodi Carstens, Earl Carstens

Research output: Contribution to journalArticle

33 Scopus citations

Abstract

This study investigated effects of nicotine applied to the tongue surface on responses of gustatory neurons in the nucleus of the solitary tract (NTS) in rats. In pentobarbital-anesthetized rats, single-unit recordings were made from NTS units responsive to one or more tastants (sucrose, NaCl, citric acid, monosodium glutamate, quinine). Application of nicotine (0.87, 8.7, or 600 mM) excited gustatory NTS units and significantly attenuated NTS unit responses to their preferred tastant in a dose-dependent manner. The depressant effect of nicotine was equivalent regardless of which tastant best excited the NTS unit. Nicotinic excitation of NTS units and depression of their tastant-evoked responses were both significantly attenuated by the nicotinic antagonist mecamylamine, which itself did not excite NTS units. In rats with bilateral trigeminal ganglionectomy, nicotine still excited nearly all NTS units but no longer depressed tastant-evoked responses. Nicotine did not elicit plasma extravasation when applied to the tongue. The results indicate that nicotine directly excites NTS units by gustatory nerves and inhibits their tastant-evoked responses by a nicotinic acetylcholine receptor-mediated excitation of trigeminal afferents that inhibit NTS units centrally.

Original languageEnglish (US)
Pages (from-to)1877-1886
Number of pages10
JournalJournal of Neurophysiology
Volume96
Issue number4
DOIs
StatePublished - Oct 2006

ASJC Scopus subject areas

  • Physiology
  • Neuroscience(all)

Fingerprint Dive into the research topics of 'Nicotine suppression of gustatory responses of neurons in the nucleus of the solitary tract'. Together they form a unique fingerprint.

  • Cite this