5-HT(1A) autoreceptor antagonist-induced 5-HT release in the hamster suprachiasmatic nuclei: effects on circadian clock resetting

Neurosci Lett. 2000 Mar 17;282(1-2):97-100. doi: 10.1016/s0304-3940(00)00873-9.

Abstract

Serotonin (5-HT) has been implicated in phase shifting of mammalian circadian rhythms by non-photic stimuli. This study tests whether pharmacological induction of endogenous 5-HT release can shift circadian phase in the Syrian hamster. Systemic injections of the 5-HT(1A) antagonist WAY100635 during the mid-subjective day significantly increased 5-HT in dialysate from the hamster suprachiasmatic nucleus (SCN) circadian pacemaker by approximately 50% for 40-60 min. However, this was not associated with phase shifts or with potentiation of phase shifts induced by a 3 h bout of running. These results indicate that enhanced 5-HT release in the SCN or possibly other regions is not sufficient to induce phase shifts in the subjective day.

Publication types

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

MeSH terms

  • Animals
  • Autoreceptors / antagonists & inhibitors*
  • Autoreceptors / physiology
  • Circadian Rhythm / physiology*
  • Cricetinae
  • Mesocricetus
  • Microdialysis
  • Physical Exertion
  • Piperazines / pharmacology*
  • Pyridines / pharmacology*
  • Receptors, Serotonin / drug effects*
  • Receptors, Serotonin / physiology
  • Receptors, Serotonin, 5-HT1
  • Serotonin / metabolism*
  • Serotonin Antagonists / pharmacology*
  • Suprachiasmatic Nucleus / drug effects
  • Suprachiasmatic Nucleus / metabolism*

Substances

  • Autoreceptors
  • Piperazines
  • Pyridines
  • Receptors, Serotonin
  • Receptors, Serotonin, 5-HT1
  • Serotonin Antagonists
  • Serotonin
  • N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide