Document Detail


Bright light exposure during the daytime affects circadian rhythms of urinary melatonin and salivary immunoglobulin A.
MedLine Citation:
PMID:  10373104     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The effects of bright light exposure during the daytime on circadian urinary melatonin and salivary immunoglobulin A (IgA) rhythms were investigated in an environmental chamber controlled at a global temperature of 27 degrees C+/-0.2 degrees C and a relative humidity of 60%+/-5%. Seven diurnally active healthy females were studied twice, in bright and dim light conditions. Bright light of 5000 lux was provided by placing fluorescent lamps about 1 meter in front of the subjects during the daytime exposure (06:30-19:30) from 06:30 on day 1 to 10:30 on day 3. Dim light was controlled at 200 lux, and the subjects were allowed to sleep from 22:30 to 06:30 under both light exposure conditions. Urine and saliva were collected at 4h intervals for assessing melatonin and IgA. Melatonin excretion in the urine was significantly greater during the nighttime (i.e., at 06:30 on day 1 and at 02:30 on day 2) after the bright light condition than during the dim light condition. Furthermore, the concentration and the amount of salivary IgA tended to be higher in the bright light than in the dim light condition, especially during the night-time. Also, salivary IgA concentration and the total amount secreted in the saliva were significantly positively correlated with urinary melatonin. These results are consistent with the hypothesis that bright light exposure during the daytime enhances the nocturnal melatonin increase and activates the mucosal immune response.
Authors:
S J Park; H Tokura
Related Documents :
129284 - Light and drug induced changes of epiphysial synaptic ribbons.
16393714 - Effect of dim and bright light exposure on some immunological parameters measured under...
15841104 - Effect of sodium valproate on nocturnal melatonin sensitivity to light in healthy volun...
7202214 - The effects of the light:dark cycle and sympathetically-active drugs on pineal n-acetyl...
9776204 - Long-term and short-term variations in amplitude and frequency of spontaneous otoacoust...
16228574 - Light-induced behavioral responses (;phototaxis') in prokaryotes.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Chronobiology international     Volume:  16     ISSN:  0742-0528     ISO Abbreviation:  Chronobiol. Int.     Publication Date:  1999 May 
Date Detail:
Created Date:  1999-07-23     Completed Date:  1999-07-23     Revised Date:  2004-11-17    
Medline Journal Info:
Nlm Unique ID:  8501362     Medline TA:  Chronobiol Int     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  359-71     Citation Subset:  IM    
Affiliation:
Department of Environmental Health, Nara Women's University, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Analysis of Variance
Body Temperature
Circadian Rhythm / physiology*
Female
Humans
Immunoglobulin A, Secretory / analysis*
Lighting*
Melatonin / urine*
Photoperiod
Regression Analysis
Saliva / immunology*
Chemical
Reg. No./Substance:
0/Immunoglobulin A, Secretory; 73-31-4/Melatonin

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  The effect of activity on the waking temperature rhythm in humans.
Next Document:  Investigation into the role of the response regulator NtrC in the metabolism and virulence of Brucel...