GENDER DIFFERENCES IN EFFECTS OF SEASON ON PATTERNS OF NOCTURNAL MELATONIN

在动物体内，褪黑激素作为一种化学物质起着重要的作用。 季节对行为影响的中介者。在许多情况下， 夜间长度的变化是环境信号， 会引发行为的季节性变化。褪黑激素是专门分泌的 在夜间，其分泌物的持续时间因季节而异 夜间长短的变化。由于这些特性，许多 生物体利用夜间褪黑素分泌持续时间的变化 作为触发功能变化的化学信号，例如繁殖， 在季节性的基础上变化。 我们最近的研究(ZO1 MH 02424-01 CPB)表明，人类在 在它们的进化过程中，有类似于 那些存在于动物体内，使它们能够检测到季节变化的东西 调节夜间褪黑激素分泌的持续时间。 在实验中检测到了人类对光周期变化的反应 个人暴露在长短人工环境中的情况 “几天。”在随后的环境中(华盛顿特区大都会)，其中 它们经常暴露在人造光下，仍然能够检测到 夜间持续时间的季节性变化以及对这些变化的反应 通过改变褪黑激素夜间周期的持续时间来改变 分泌物。我们发现大鼠夜间褪黑激素的分泌模式 妇女对夜间持续时间的季节性变化作出反应，而 男性的情况并非如此。这一发现表明，可能存在性别差异 对人工光照机制的反应差异 跟踪夜间长度的季节性变化。 因为夜间褪黑激素持续时间的重要性 分泌物作为季节变化的影响的换能器 夜间动物行为的长短，重要的是 研究褪黑素是否在糖尿病的发病机制中起作用 季节性情感障碍(SAD)伴反复发作的冬季抑郁。 因此，在这个项目中，我们正在评估是否 夜间褪黑激素分泌的持续时间随季节变化。 患有SAD的妇女，就像健康的妇女一样。初步结果： 大约20名患者和20名匹配的对照组表明褪黑素 患有SAD的女性对季节变化的反应异常迟钝。这些 结果增加了这样的可能性，当松果体不能 表现出健康女性通常会出现的季节性反应。在.期间 今年，科目数量增加了一倍，以便 进一步评估这一意想不到的、潜在的重要发现。

In animals, the hormone, melatonin, plays an important role as a chemical mediator of the effects of season on behavior. In many instances, changes in the length of the night serve as the environmental signal that triggers seasonal changes in behavior. Melatonin is secreted exclusively at night, and the duration of its secretion varies with seasonal variations in the length of the night. Because of these properties, many organisms use changes in the duration of nocturnal melatonin secretion as a chemical cue to trigger changes in functions, such as breeding, that vary on a seasonal basis. Our recent research (ZO1 MH 02424-01 CPB) showed that humans, in the course of their evolution, have conserved brain mechanisms similar to those that exist in animals that enable them to detect seasonal changes in night-length and modify the duration of nocturnal melatonin secretion. Human responses to change in photoperiod were detected in experimental conditions in which individuals were exposed to long and short artificial "days." In a subsequent environment (metro Washington, DC area), in which they are routinely exposed to artificial light, are still able to detect seasonal changes in the duration of the night and to respond to these changes by modifying the duration of the nocturnal period of melatonin secretion. We found that patterns of nocturnal melatonin secretion in women responded to seasonal changes in the duration of the night, while those in men did not. This finding suggests that there may be gender differences in responsiveness to artificial light of mechanisms that track seasonal changes in the length of the night. Because of the importance of the duration of nocturnal melatonin secretion as a transducer of the effects of seasonal changes in the length of the night on animal behavior, it would be important to investigate whether melatonin plays a role in the pathogenesis of seasonal affective disorder (SAD) with recurrent winter depression. Accordingly, in this project, we are assessing whether or not the duration of nocturnal melatonin secretion varies on a seasonal basis in women with SAD, as it does in healthy women. Preliminary results with approximately 20 patients and 20 matched controls suggest that melatonin is abnormally unresponsive to change in season in women with SAD. These results raise the possibility that when the pineal gland fails to exhibit a seasonal response that normally occurs in healthy women. During the current year, the number of subjects is being doubled in order to further evaluate this unexpected and potentially important finding.