melatonin


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melatonin:

see pineal glandpineal gland
, small organ (about the size of a pea) situated in the brain. Long considered vestigial in humans, the structure, which is also called the pineal body or the epiphysis, is present in most vertebrates.
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melatonin

[‚mel·ə′tōn·ən]
(biochemistry)
A hormone secreted by the pineal gland that acts on melanophores in the skins of amphibians and reptiles to concentrate the melanin in the center of the cells, lightening the body surface; in higher vertebrates it conveys information about time that influences reproduction and circadian physiology.
References in periodicals archive ?
The sympathetic supply is important for regulation of melatonin production (Figure 1).
Melatonin is a crucial tool we can use to re-synchronize our lives," said David Hilton, R&D Director of Natrol, LLC.
With the current popularity and wide usage of melatonin supplements for sleep support, CRN wanted to clarify responsible labeling and marketing practices for its member companies, and for the industry, by developing science-based voluntary guidelines to help ensure these products best serve consumers safely," said Andrea Wong, PhD, vice president, scientific & regulatory affairs, CRN.
When this happens, melatonin is often the missing piece of the puzzle.
Pineal melatonin synthesis is affected by the intensity of light.
They observed improvement in mitochondrial respiration and a reduction in oxidative status among both lean and obese animals that received melatonin.
It was found that Melatonin caused delaying of tumour formation and also was capable of bringing along significant slowdown of their growth but the use of tamoxifen led to a huge regression of tumours in rats with either high night time levels of melatonin during absolute darkness or in the rats who were on melatonin supplementation during dim light at night exposure.
Melatonin is known most prominently for its ability to support healthy sleep.
However, the study only found an association, and cannot prove that low melatonin levels cause Type 2 diabetes, website MyHealthNewsDaily reported.
Being exposed to bright lights in the evening or too little light during the day can disrupt the body's normal melatonin cycles.
Researchers from a Boston hospital found that women with low levels of melatonin in their body were more than twice as likely to develop Type 2 diabetes as those with high levels.