Effects of melatonin on neuronal activity in the rat suprachiasmatic nucleus in vitro

Shigenobu Shibata, Vincent M. Cassone, Robert Y. Moore

Research output: Contribution to journalArticle

135 Citations (Scopus)


The pineal hormone melatonin is believed to act directly on the hypothalamic suprachiasmatic nuclei (SCN), which are principal circadian pacemakers in rodents, although direct demonstration of this is lacking. To determine whether the SCN are sensitive to melatonin electrophysiologically, we investigated the effect of melatonin on rat SCN single-unit activity in an in vitro hypothalamic slice preparation. SCN single-unit activity was inhibited by melatonin superfusion during the late subjective day in a dose-dependent manner but not at other times of day, supporting the view that melatonin acts directly on SCN neurons.

Original languageEnglish
Pages (from-to)140-144
Number of pages5
JournalNeuroscience Letters
Issue number1-2
Publication statusPublished - 1989 Feb 13



  • Circadian rhythm
  • Melatonin
  • Single-unit activity
  • Suprachiasmatic nucleus

ASJC Scopus subject areas

  • Neuroscience(all)

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