Aoki H, Yamada N, Ozeki Y, Yamane H, Kato N
Department of Psychiatry, Shiga University of Medical Science, Otsu, Japan.
Neurosci Lett. 1998 Aug 14;252(2):91-4. doi: 10.1016/s0304-3940(98)00548-5.
We set out to determine the minimum intensity of light able to suppress nocturnal melatonin levels as measured in normal human saliva. Five healthy male volunteers were exposed to light at different intensities (<10, 500, 1000, 2500, and 5000 lux) in a repeated measure design. Suppression of melatonin was dependent on both light intensity and duration of light exposure. Minimum intensities of light suppressing nocturnal melatonin levels were calculated as 393, 366, 339, and 285 lux for exposure durations of 30, 60, 90, and 120 min, respectively. Minimum effective intensity and duration of light exposure showed a linear inverse relationship. These results suggest that less intensity of light than previously reported suffices to suppress melatonin in humans, and that caution is required in interpreting studies using long exposure to dim light as a background condition.
我们着手确定能够抑制正常人唾液中夜间褪黑激素水平的最低光照强度。采用重复测量设计，让五名健康男性志愿者暴露于不同强度（<10、500、1000、2500和5000勒克斯）的光照下。褪黑激素的抑制取决于光照强度和光照持续时间。对于30、60、90和120分钟的暴露持续时间，抑制夜间褪黑激素水平的最低光照强度分别计算为393、366、339和285勒克斯。最低有效光照强度和暴露持续时间呈线性反比关系。这些结果表明，低于先前报道的光照强度足以抑制人体中的褪黑激素，并且在解释以长时间暴露于暗光作为背景条件的研究时需要谨慎。
