Get access

Vitamin A is a necessary factor for sympathetic- independent rhythmic activation of mitogen-activated protein kinase in the rat pineal gland

Authors

  • F. Guillaumond,

    1. EA Laboratoire d'Interactions Fonctionnelles Neuroendocriniennes,
    Search for more papers by this author
  • F. Giraudet,

    1. INSERM EPI 9902 Laboratoire d'Otologie Neuro-Otologie and
    Search for more papers by this author
  • D. Becquet,

    1. CNRS UMR 6544 Laboratoire des Interactions Cellulaires en Neuroendocrinologie, Institut Fédératif Jean-Roche, Université de la Méditerranée, Faculté de Médecine Nord, Boulevard Pierre Dramard, 13916 Marseille cedex 20, France
    Search for more papers by this author
  • D. Sage,

    1. EA Laboratoire d'Interactions Fonctionnelles Neuroendocriniennes,
    Search for more papers by this author
  • G. Laforge-Anglade,

    1. EA Laboratoire d'Interactions Fonctionnelles Neuroendocriniennes,
    Search for more papers by this author
  • O. Bosler,

    1. CNRS UMR 6544 Laboratoire des Interactions Cellulaires en Neuroendocrinologie, Institut Fédératif Jean-Roche, Université de la Méditerranée, Faculté de Médecine Nord, Boulevard Pierre Dramard, 13916 Marseille cedex 20, France
    Search for more papers by this author
  • A. M. François-Bellan

    1. CNRS UMR 6544 Laboratoire des Interactions Cellulaires en Neuroendocrinologie, Institut Fédératif Jean-Roche, Université de la Méditerranée, Faculté de Médecine Nord, Boulevard Pierre Dramard, 13916 Marseille cedex 20, France
    Search for more papers by this author

Dr Anne-Marie François-Bellan, as above.
E-mail: francois.am@jean-roche.univ-mrs.fr

Abstract

The circadian clock in the suprachiasmatic nucleus (SCN) controls day-to-day physiology and behavior by sending timing messages to multiple peripheral oscillators. In the pineal gland, a major SCN target, circadian events are believed to be driven exclusively by the rhythmic release of norepinephrine from superior cervical ganglia (SCG) neurons relaying clock messages through a polysynaptic pathway. Here we show in rat an SCN-driven daily rhythm of pineal MAPK activation that is not dependent on the SCG and whose maintenance requires vitamin A as a blood-borne factor. This finding challenges the dogma that SCG-released norepinephrine is an exclusive mediator of SCN–pineal communication and allows the assumption that humoral mechanisms are involved in pineal integration of temporal messages.

Get access to the full text of this article

Ancillary