Circadian and seasonal changes in human plasma orexin-A and serum melatonin

1. 受试者为8名健康的年轻成人，平均年龄24.8岁，居住在日本kfu附近，所有受试者均获得书面知情同意。口府位于北纬35°40′，东经138°34′，夏天和冬天的日出和日落时间相差约2小时20分钟。日本还没有引入夏令时。研究对象分别在夏季和冬季填写了一个月的睡眠记录，并以10分钟为周期对睡眠-觉醒状态进行评分。在睡眠记录的基础上，每天的睡眠开始和偏移时间被寻找，并计算出每个月的平均水平。在夏季和冬季，受试者在实验设施中停留24小时。厂房内照度低于15.1倍。通过前臂静脉留置导管每隔1 ~ 3小时取血一次。血清褪黑素测定采用RIA法。计算了拟合的三谐回归模型（3HMAX）的极值相位。睡眠开始时间夏季为0141 h，冬季为0200 h（统计学上n. s.），睡眠偏移时间分别为0751 h和0824 h。3HMAX夏季为0258 h，冬季为0406 h。所有受试者均获得orexin - a的书面知情同意。5名受试者（26.0岁）分别于夏季和冬季在实验设施中停留24 h。每隔1小时采血一次。采用RIA法检测血浆食欲素a。血浆食欲素a在夏季和冬季均无昼夜变化。夏季的orexin-A平均值为47.1 pg/ml，高于冬季的21.4 pg/ml。

1. Sleep onset, offset and serum melatoninSubjects were eight healthy young adults (mean age 24.8 years) who lived around Kofu, Japan, Written informed consent was obtained from all the subjects. Kofu is located at 35°40' N and 138°34'E, and sunrise and sunset times in the summer and winter differ by about 2 h and 20 min. In Japan daylight-saving time has not been introduced. The subjects filled out a sleep log for one month in both the summer and winter, and the sleep-wake state was scored in 10-minute epochs. Based on the sleep log, daily sleep onset and offset times were looked for, and individual monthly averages were calculated. The subjects stayed in the experimental facility for 24 h in both the summer and winter. Illumination in the facility was less than 15 1x. Blood was sampled through an indwelling catheter in the forearm vein at 1-h to 3-h intervals. Serum melatonin was assayed by RIA. The phase of maximum of fitted three-harmonic regression model (3HMAX) was calculated. Sleep onset times were 0141 h in the summer and 0200 h in the winter (statistically n. s.), and sleep offset times were 0751 h and 0824 h, respectively. 3HMAX were 0258 h in the summer and 0406 h in the winter.2. Orexin-AWritten informed consent was obtained from all the subjects. Five subjects (26.0 years) stayed in the experimental facility for 24 h in both the summer and winter. Blood was sampled at 1-h intervals. Plasma orexin-A was assayed by RIA. Plasma orexin-A showed no circadian variation in both the summer and winter. But orexin-A in the summer (mean value 47.1 pg/ml) was higher than that in the winter (21.4 pg/ml).