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.
|Original language||English (US)|
|Number of pages||10|
|State||Published - Apr 2004|
Bibliographical noteFunding Information:
We gratefully thank Miss Gabriele Schönhuber for her technical assistance in performing the radioimmunoassays. This study was supported by U.S. National Institutes of Health (GM-13981) (FH) and Dr. h.c. Dr. h.c. Earl Bakken Fund (GC, FH).
- Neuropeptide Y (NpY)
- Plasma concentrations
- Substance P (SP)
- Vasoactive intestinal peptide (VIP)