Sandyk R
Democrition University of Thrace, Department of Medical Physics and Polytechnic School, Alexandroupolis and Xanthi, Greece.
Int J Neurosci. 1992 Mar;63(1-2):105-14. doi: 10.3109/00207459208986660.
The discovery in 1953 of rapid eye movement (REM) sleep and the appreciation that sleep is a heterogeneous physiological state stimulated major research into sleep disorders. Electroencephalographic studies have shown that the amount of REM sleep changes with age. While newborns spend almost 50% of their sleep time in REM, the percentage of REM sleep decreases to 30% by the age of 3 months and to 20% by the age of 6 months. In addition, newborns enter REM sleep soon after the initiation of sleep, but by the age of 4 months entry into sleep assumes the adult pattern in which a significant period of non-REM sleep precedes the onset of REM sleep. Since reduction in the amount of REM sleep is associated with cerebral maturation and since the pineal gland has been implicated both in cerebral development and in the organization of REM sleep, the pineal gland may be involved in the maturation of the adult REM sleep pattern. Prior to the age of 3 months melatonin plasma levels are low and the characteristic circadian rhythms of melatonin are absent. Thereafter, melatonin secretion increases and circadian rhythmicity of melatonin becomes apparent. Thus, the abundance of REM sleep during the first 3 months of infancy is associated with deficient pineal melatonin functions, while the decline in the percentage of REM sleep coincides with the emergence of melatonin secretion coincident with the maturation of the pineal gland. I propose, therefore, that a state of low melatonin secretion is permissive for REM sleep and that maturation of the pineal gland retards REM sleep. This hypothesis is supported by the findings that melatonin suppresses REM sleep in cats and that in rats and humans pinealectomy induces a narcoleptic-like pattern of REM sleep which strikingly resembles that of the newborn and which is reversed by the administration of melatonin. A further hypothesis is advanced to explain the pathophysiology of narcolepsy in terms of a maturational defect of the pineal gland in infancy.
1953年快速眼动（REM）睡眠的发现以及认识到睡眠是一种异质性生理状态，激发了对睡眠障碍的重大研究。脑电图研究表明，REM睡眠量随年龄变化。新生儿几乎50%的睡眠时间处于REM睡眠，到3个月大时，REM睡眠百分比降至30%，到6个月大时降至20%。此外，新生儿在睡眠开始后很快进入REM睡眠，但到4个月大时，进入睡眠呈现成人模式，即REM睡眠开始前有一段显著的非REM睡眠期。由于REM睡眠量的减少与大脑成熟有关，且松果体在大脑发育和REM睡眠的组织中都有涉及，因此松果体可能参与了成人REM睡眠模式的成熟。在3个月大之前，血浆褪黑素水平较低，且缺乏褪黑素典型的昼夜节律。此后，褪黑素分泌增加，褪黑素的昼夜节律变得明显。因此，婴儿期前3个月REM睡眠丰富与松果体褪黑素功能不足有关，而REM睡眠百分比的下降与褪黑素分泌的出现以及松果体的成熟相吻合。因此，我提出低褪黑素分泌状态有利于REM睡眠，而松果体的成熟会延迟REM睡眠。这一假设得到以下发现的支持：褪黑素抑制猫的REM睡眠，在大鼠和人类中，松果体切除会诱发类似发作性睡病的REM睡眠模式，这种模式与新生儿的模式惊人相似，且通过给予褪黑素可逆转。进一步提出一个假设来解释发作性睡病的病理生理学，即婴儿期松果体的成熟缺陷。
