REGULATION OF HUMAN BIOLOGY BY CHANGES IN DAYLENGTH

昼长变化对人类生物学的调节

• 批准号: 3859966
• 负责人: T A WEHR
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3859966
• 关键词: REM sleep; behavioral medicine; biological clocks; bioperiodicity; body temperature; circadian rhythms; cortisol; environmental adaptation; functional ability; hormone regulation /control mechanism; light adaptations; melatonin; photobiology; prolactin; sleep

Most living things exhibit striking seasonal changes during the course of the year. In many cases, the changes are known to be induced by seasonal changes in day length, or photoperiod. Changes in the photoperiod generally affect animals in two ways. First, the constant daily expansion or contraction of the photoperiod can cause an animal's daily activity or rest phase to expand or contract, so that it matches the photoperiod. Second, specific changes in the photoperiod can trigger new behaviors, such as hibernation, migration, or breeding, that represent adaptations to conditions that prevail during a particular season. These new behaviors are often accompanied by and depend on marked changes in the biochemistry, physiology and anatomy of the organism. Basic researchers have proposed that the photoperiod controls the organism through its effects on a biological clock mechanism that employs two separate circadian oscillators to track the constantly changing times of dawn and dusk through the course of the year. This project is designed to investigate whether human biology is similarly subject to control by changes in the photoperiod. We monitor daily patterns of sleep, hormones and body temperature in individuals who live for one month on a schedule of light exposures that simulate a natural winter day. They move about freely in ambient natural and artificial light for ten hours each day but are confined to a dark room for fourteen hours each night. For comparison, we make similar measurements in the same individuals while they live for one week on a conventional schedule in which they are exposed to ambient light for sixteen hours each day and sleep in a dark room for eight hours each night. The results of the experiment suggest that the human circadian system is similar to that of other animals-that it is composed of two subsystems, one of which is synchronized with dawn and the other with dusk. This conclusion is based on the following observations: After night was artificially expanded to fourteen hours, sleep divided into two components that gradually moved apart. The evening component (E) was associated with the daily offset of cortisol secretion, onset of melatonin secretion, onset of prolactin secretion, onset of sleep, peak of slow wave sleep and decline in body temperature, and it was entrained to dusk. The morning component (M) was associated with the daily onset of cortisol secretion, offset of melatonin secretion, offset of prolactin secretion, peak of REM sleep, rise in body temperature and onset of wakefulness, and it was entrained to dawn. The results are likely to have important implications for human biology and medicine.

大多数生物在生命过程中都会表现出显着的季节变化 那一年。 在许多情况下，已知这些变化是由季节性引起的 日长或光周期的变化。 光周期的变化 通常以两种方式影响动物。 一、每日不断扩张 或光周期的缩短会导致动物的日常活动或 休息阶段扩大或收缩，使其与光周期相匹配。 其次，光周期的特定变化可以引发新的行为，例如 冬眠、迁徙或繁殖，代表着对环境的适应 特定季节盛行的条件。 这些新行为 通常伴随并依赖于生物化学的显着变化， 有机体的生理学和解剖学。 基础研究人员提出光周期控制生物体 通过它对生物钟机制的影响，该机制采用两种 单独的昼夜节律振荡器来跟踪不断变化的时间 一年中的黎明和黄昏。 该项目旨在研究人类生物学是否具有类似的特征 受光周期变化的控制。 我们每天监控 居住者的睡眠模式、激素和体温 按照模拟自然光照射的时间表进行一个月 冬天的一天。 它们在周围的自然光和人造光下自由移动 每天十个小时，但十四个小时被关在暗室里 每个晚上。 为了进行比较，我们在相同的情况下进行了类似的测量 个人按常规时间表生活一周 他们每天暴露在环境光下十六个小时 每晚在黑暗的房间里睡八个小时。 实验结果表明，人体的昼夜节律系统是 与其他动物相似——它由两个子系统组成，一是 其中一个与黎明同步，另一个与黄昏同步。 这 结论基于以下观察： 人为延长到十四小时，睡眠分为两部分 就这样渐渐疏远了。 晚间成分 (E) 与 皮质醇分泌的每日偏移、褪黑激素分泌的开始、开始 催乳素分泌、睡眠开始、慢波睡眠峰值和下降 体温，又夹带到了黄昏。 上午部分 (M) 与皮质醇分泌的每日开始、抵消 褪黑激素分泌、催乳素分泌抵消、快速眼动睡眠峰值、上升 体温和觉醒的开始，它被夹带到黎明。 研究结果可能对人类生物学产生重要影响 药品。