title: Dose-response relationship between light irradiance and the suppression of plasma melatonin in human volunteers.
abstract: This study tested the capacity of different irradiances of monochromatic light to reduce plasma melatonin in normal humans. Six healthy male volunteers, 24-34 years old, were exposed to 0.01, 0.3, 1.6, 5, or 13 microW/cm2 of 509 nm monochromatic light for 1 h during the night on separate occasions. Light irradiance depressed plasma melatonin in a dose-response pattern. The data indicate that the mean threshold irradiance for suppressing melatonin is between 1.6 and 5 microW/cm2. Individual variations in threshold responses to monochromatic light were observed among the volunteers.
authors.affiliation: Department of Neurology, Jefferson Medical College, Philadelphia, PA 19107.
authors.forename: G C
authors.initials: GC
authors.lastname: Brainard
authors.forename: A J
authors.initials: AJ
authors.lastname: Lewy
authors.forename: M
authors.initials: M
authors.lastname: Menaker
authors.forename: R H
authors.initials: RH
authors.lastname: Fredrickson
authors.forename: L S
authors.initials: LS
authors.lastname: Miller
authors.forename: R G
authors.initials: RG
authors.lastname: Weleber
authors.forename: V
authors.initials: V
authors.lastname: Cassone
authors.forename: D
authors.initials: D
authors.lastname: Hudson
mesh_terms: D000328:Adult; D006801:Humans; D008029:Lighting; D008297:Male; D008550:Melatonin / Q000097:blood*; D010870:Pineal Gland / Q000378:metabolism / Q000502:physiology*
chemical_list: D008550:Melatonin