Laakso M L, Hätönen T, Stenberg D, Alila A, Smith S
Department of Physiology, University of Helsinki, Finland.
J Pineal Res. 1993 Aug;15(1):21-6. doi: 10.1111/j.1600-079x.1993.tb00505.x.
Salivary melatonin levels were measured in 12 healthy volunteers in order to determine whether a moderate light intensity, which suppresses the nocturnal rise of melatonin, was able to shift the melatonin rhythm. The samples were collected at 1-hr intervals under lighting of < 100 lux (experiment 1) or < 10 lux (experiment 2). The control melatonin profiles were determined during the first night. In the second night the subjects were exposed to light of 500 lux for 60 min during the rising phase of melatonin synthesis. The third series of samples was collected during the third night. The mean decrease of melatonin levels by the exposure to light was 56% of the prelight concentrations. The melatonin onset times were delayed significantly (about 30 min) the night after the exposure to light. The melatonin offset times tended to be delayed in experiment 2. The shifts of the melatonin offset correlated positively with the amount of the melatonin suppression. The results suggest that a relatively small and short lasting light-induced interruption of melatonin synthesis may affect the melatonin rhythm in humans.
为了确定抑制褪黑素夜间升高的中等光照强度是否能够改变褪黑素节律，对12名健康志愿者的唾液褪黑素水平进行了测量。在<100勒克斯（实验1）或<10勒克斯（实验2）的光照条件下，每隔1小时采集一次样本。在第一个晚上测定对照褪黑素曲线。在第二个晚上，在褪黑素合成上升阶段，让受试者暴露于500勒克斯的光照下60分钟。在第三个晚上采集第三组样本。光照导致褪黑素水平平均下降至光照前浓度的56%。光照后当晚，褪黑素开始时间显著延迟（约30分钟）。在实验2中，褪黑素结束时间有延迟的趋势。褪黑素结束时间的变化与褪黑素抑制量呈正相关。结果表明，相对较小且持续时间较短的光照诱导的褪黑素合成中断可能会影响人类的褪黑素节律。
