Document Detail


Acute effects of bright light exposure on cortisol levels.
MedLine Citation:
PMID:  20484692     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Multisynaptic neural and endocrine pathways from the suprachiasmatic nucleus of the hypothalamus have been hypothesized to communicate circadian and photic information to the adrenal glands. In humans, light exposure has been reported to have no effect, increase, or decrease cortisol levels. These inconsistent findings in humans may be related to differences among studies including the intensity (approximately 500 to 5500 lux), duration (15 min to 4 h), and circadian phase of light exposure. The authors assessed the influence of exposure to bright light on cortisol levels in humans during the rising and descending phases of the circadian rhythm of cortisol, that is, when cortisol levels are high. Twenty healthy men and women were studied using a within-subject research design. Subjects were studied in an environment free of time cues for 9 to 10 days. Subjects received a 6.7-h exposure of bright light (approximately 10,000 lux; equivalent to ambient light intensity just after sunrise or just before sunset) or dim light (approximately 3 lux; equivalent to candle light) during the biological night and morning. Bright light exposure significantly reduced plasma cortisol levels at both circadian phases studied, whereas dim light exposure had little effect on cortisol levels. The finding of an acute suppressive effect of bright light exposure on cortisol levels supports the existence of a mechanism by which photic information can acutely influence the human adrenal glands.
Authors:
Christopher M Jung; Sat Bir S Khalsa; Frank A J L Scheer; Christian Cajochen; Steven W Lockley; Charles A Czeisler; Kenneth P Wright
Publication Detail:
Type:  Journal Article; Research Support, N.I.H., Extramural; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of biological rhythms     Volume:  25     ISSN:  1552-4531     ISO Abbreviation:  J. Biol. Rhythms     Publication Date:  2010 Jun 
Date Detail:
Created Date:  2010-05-20     Completed Date:  2010-08-12     Revised Date:  2014-09-18    
Medline Journal Info:
Nlm Unique ID:  8700115     Medline TA:  J Biol Rhythms     Country:  United States    
Other Details:
Languages:  eng     Pagination:  208-16     Citation Subset:  IM    
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MeSH Terms
Descriptor/Qualifier:
Adrenal Glands / radiation effects
Adult
Biological Clocks
Circadian Rhythm
Dose-Response Relationship, Radiation
Female
Humans
Hydrocortisone / blood*,  radiation effects*
Light*
Male
Melatonin / blood,  radiation effects
Photic Stimulation
Photoperiod
Grant Support
ID/Acronym/Agency:
M01-RR-02635/RR/NCRR NIH HHS; R01 HL081761/HL/NHLBI NIH HHS; R01 HL081761-04/HL/NHLBI NIH HHS; R01-HL081761/HL/NHLBI NIH HHS; R01-MH45130/MH/NIMH NIH HHS
Chemical
Reg. No./Substance:
JL5DK93RCL/Melatonin; WI4X0X7BPJ/Hydrocortisone
Comments/Corrections

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