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Published on: March 19, 2017
Preliminary evidence for spectral opponency in the suppression of melatonin by light in humans
Mariana G Figueiro1, John D Bullough, Robert H Parsons
1Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA.
Abstract:
Human adult males were exposed to light from blue light emitting diodes (18 lux; 29 microW/cm) and from clear mercury vapor lamps (450 lux; 170 microW/cm) during night-time experimental sessions. Both conditions suppressed nocturnal melatonin concentrations in blood plasma with the blue light more effective than mercury at melatonin suppression. No additive model incorporating opsin photopigments either alone or in combination could explain the results, but a model incorporating an opponent mechanism was consistent with the present data as well as data from previously published studies.
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