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melatonin hormone

hormone secreted from the pineal gland

Note 1 to entry: Levels of melatonin in the pineal gland, blood, saliva, and urine fluctuate in a circadian rhythm, higher at night and lower in the daytime, following the biological clock that is itself set naturally by day/night photoperiods. Light at night reduces melatonin, while decoupling the biological and natural (or artificially induced) photoperiods causes disruption of sleep/wake cycles (e.g. jet lag).

Note 2 to entry: This entry was numbered 17-762 in CIE S 017:2011.

Publication date: 2020-12
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