Sleep and Melatonin in Diurnal and Nocturnal Rodents

许多研究表明，褪黑激素可以诱导人类睡眠。然而，负责这种效应的大脑机制尚不清楚。这是由于缺乏褪黑激素催眠作用的实验室啮齿动物模型;试图在实验室啮齿动物中用褪黑激素诱导睡眠的尝试使用了夜间啮齿动物，这意味着啮齿动物在周期的黑暗阶段活跃，如大鼠和Djungarian仓鼠。褪黑激素并不总是诱导这些啮齿动物的睡眠。事实上，在大多数研究中，褪黑激素减少了睡眠，增加了觉醒。因为这些夜行动物在夜间最活跃，当褪黑激素分泌最高时，这些结果不应该令人惊讶。需要一个昼夜啮齿动物模型来证明褪黑激素的睡眠诱导作用。Arvicanthis niloticus（unstriped Nile grass rat）是一种昼行性啮齿类动物，是研究褪黑激素诱导睡眠作用的理想动物。此外，使用这种啮齿动物作为模型，可以研究褪黑激素诱导睡眠的大脑回路。这些研究的结果可能会澄清褪黑激素如何用于治疗失眠，

Numerous studies have shown that melatonin can induce sleep in humans. However, the brain mechanisms responsible for this effect are unknown. This is due to the lack of a laboratory rodent model of the soporific effects of melatonin; attempts to induce sleep with melatonin in laboratory rodents have used nocturnal rodents, meaning rodents active during the dark phase of the cycle, such as rats and Djungarian hamsters. Melatonin does not consistently induce sleep in these rodents. In fact, in most of these studies, melatonin reduced sleep and increased wakefulness. Because these nocturnal animals are most active during the night, when melatonin secretion is the highest, these results should not be surprising. A diurnal rodent model is needed to demonstrate the sleep-inducing effects of melatonin. Arvicanthis niloticus (unstriped Nile grass rat), a diurnal murid rodent, is an ideal animal in which to demonstrate the sleep-inducing effects of melatonin. Further, using this rodent as a model, the brain circuitry through which melatonin induces sleep can be investigated. Results from these studies may clarify how melatonin can be used to treat insomnia and