| Autor: |
Vartanian, Garen V., Li, Benjamin Y., Chervenak, Andrew P., Walch, Olivia J., Pack, Weston, Ala-Laurila, Petri, Wong, Kwoon Y. |
| Předmět: |
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| Zdroj: |
Journal of Biological Rhythms; Aug2015, Vol. 30 Issue 4, p351-354, 4p |
| Abstrakt: |
The retina drives various non-image-forming photoresponses, including circadian photoentrainment and pupil constriction. Previous investigators showed that in humans, photic suppression of the clock-controlled hormone melatonin is most sensitive to 460-nm blue light, with a threshold of ~12 log photons cm-2 s-1. This threshold is surprising because non-image-forming vision is mediated by intrinsically photosensitive retinal ganglion cells, which receive rod-driven synaptic input and can respond to light levels as low as ~7 log photons cm-2 s-1. Using a protocol that enhances data precision, we have found the threshold for human melatonin suppression to be ~10 log photons cm-2 s-1 at 460 nm. This finding has far-reaching implications since there is mounting evidence that nocturnal activation of the circadian system can be harmful. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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