Neuropeptide chronomics in clinically healthy young adults: circaoctohoran and circadian patterns

Peptides. 2004 Apr;25(4):533-42. doi: 10.1016/j.peptides.2004.02.008.


Endothelin-1 (ET-1) undergoes an about 8-h (circaoctohoran) rather than a circadian variation in clinical health. Herein, 24 h plasma concentrations of vasoactive intestinal peptide (VIP), substance P (SP), neuropeptide Y (NpY), and cortisol used as reference, were obtained from 20 healthy young adults starting at 07:00 or 19:00 h. Like ET-1, SP and NpY undergo a circaoctohoran variation, whereas VIP is circadian rhythmic, peaking during the night, some 8 h prior to the circadian acrophase of cortisol. Maps of circadian and extra-circadian patterns may serve for screening, diagnosis and a better understanding of mechanisms underlying the etiology of various diseases.

Publication types

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

MeSH terms

  • Adult
  • Circadian Rhythm* / physiology
  • Diagnosis
  • Disease / etiology
  • Endothelin-1 / blood*
  • Female
  • Humans
  • Hydrocortisone / blood*
  • Male
  • Neuropeptide Y / blood*
  • Substance P / blood*
  • Vasoactive Intestinal Peptide / blood*


  • Endothelin-1
  • Neuropeptide Y
  • Substance P
  • Vasoactive Intestinal Peptide
  • Hydrocortisone