Regulation of vasoactive intestinal polypeptide release in the suprachiasmatic nucleus circadian clock

Timing of the mammalian circadian clock of the suprachiasmatic nucleus (SCN) is regulated by photic input from the retina. Retinorecipient units entrain rhythmicity of SCN pacemaker cells in part through their release of vasoactive intestinal polypeptide (VIP). The underlying nature of this process is conjectural, however, as in-vivo SCN VIP release has never been measured. Here, SCN microdialysis was used to investigate mechanisms regulating VIP. Hamsters under light-dark cycle of 14 : 10 exhibited a daily peak in synaptic VIP release near midday. Under constant darkness, this output was arrhythmic. Light and the glutamatergic agonist, N-methyl-D-aspartate, stimulated VIP release at night, whereas the serotonin (1A,7) agonist, (±)8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide, suppressed release at midday. Hence, SCN VIP activity is stimulated by photic input and inhibited by serotonin.

[1]  R. Moore,et al.  A retinohypothalamic projection in the rat , 1972, The Journal of comparative neurology.

[2]  J. H. Zar,et al.  Biostatistical Analysis (5th Edition) , 1984 .

[3]  A. Beaudet,et al.  VIP neurons as prime synaptic targets for serotonin afferents in rat suprachiasmatic nucleus: a combined radioautographic and immunocytochemical study , 1985, Journal of neurocytology.

[4]  S. T. Inouye,et al.  Photic regulation of peptides located in the ventrolateral subdivision of the suprachiasmatic nucleus of the rat: daily variations of vasoactive intestinal polypeptide, gastrin-releasing peptide, and neuropeptide Y , 1993, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[5]  Masaki Tanaka,et al.  The direct retinal projection to VIP neuronal elements in the rat SCN , 1993, Brain Research Bulletin.

[6]  S. Ying,et al.  Effects of serotonergic agonists on firing rates of photically responsive cells in the hamster suprachiasmatic nucleus , 1994, Brain Research.

[7]  M. Rea,et al.  Serotonin modulates photic responses in the hamster suprachiasmatic nuclei , 1994, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[8]  B. Rusak,et al.  Neuropeptides phase shift the mammalian circadian pacemaker , 1995, The Journal of neuroscience : the official journal of the Society for Neuroscience.

[9]  Shigenori Watanabe,et al.  Involvement of vasoactive intestinal polypeptide in NMDA-induced phase delay of firing activity rhythm in the suprachiasmatic nucleus in vitro , 1994, Neuroscience & Biobehavioral Reviews.

[10]  F. Ebling.  The role of glutamate in the photic regulation of the suprachiasmatic nucleus , 1996, Progress in Neurobiology.

[11]  W. Schwartz,et al.  Light‐induced c‐Fos Expression in the Mouse Suprachiasmatic Nucleus: Immunoelectron Microscopy Reveals Co‐localization in Multiple Cell Types , 1997, The European journal of neuroscience.

[12]  G. E. Pickard,et al.  TFMPP, a 5HT1B receptor agonist, inhibits light-induced phase shifts of the circadian activity rhythm and c-Fos expression in the mouse suprachiasmatic nucleus , 1997, Neuroscience Letters.

[13]  T. E. Dudley,et al.  Endogenous Regulation of Serotonin Release in the Hamster Suprachiasmatic Nucleus , 1998, The Journal of Neuroscience.

[14]  D. McMahon,et al.  Serotonin modulates glutamate responses in isolated suprachiasmatic nucleus neurons. , 1999, Journal of neurophysiology.

[15]  D. Cutler,et al.  Vasoactive intestinal polypeptide (VIP) phase‐shifts the rat suprachiasmatic nucleus clock in vitro , 2001, The European journal of neuroscience.

[16]  C. Smart,et al.  WAY-100635, a specific 5-HT1A antagonist, can increase the responsiveness of the mammalian circadian pacemaker to photic stimuli , 2001, Neuroscience Letters.

[17]  R. Moore,et al.  Suprachiasmatic nucleus in the mouse: retinal innervation, intrinsic organization and efferent projections , 2001, Brain Research.

[18]  E. Maywood,et al.  The VPAC2 Receptor Is Essential for Circadian Function in the Mouse Suprachiasmatic Nuclei , 2002, Cell.

[19]  P. Pévet,et al.  Per and neuropeptide expression in the rat suprachiasmatic nuclei: compartmentalization and differential cellular induction by light , 2002, Brain Research.

[20]  J. Hannibal,et al.  Vasoactive intestinal polypeptide induces per1 and per2 gene expression in the rat suprachiasmatic nucleus late at night , 2002, The European journal of neuroscience.

[21]  H. Okamura,et al.  A diurnal variation of vasoactive intestinal peptide (VIP) mRNA under a daily light-dark cycle in the rat suprachiasmatic nucleus , 2004, Histochemistry.

[22]  Rae Silver,et al.  Orchestrating time: arrangements of the brain circadian clock , 2005, Trends in Neurosciences.

[23]  Evaluation of serotonin, noradrenaline and dopamine reuptake inhibitors on light-induced phase advances in hamster circadian activity rhythms , 2007, Psychopharmacology.

[24]  G. Kaur,et al.  Roles of light and serotonin in the regulation of gastrin‐releasing peptide and arginine vasopressin output in the hamster SCN circadian clock , 2010, The European journal of neuroscience.

[25]  G. Kaur,et al.  On the intrinsic regulation of neuropeptide Y release in the mammalian suprachiasmatic nucleus circadian clock , 2010, The European journal of neuroscience.