Selbach Oliver, Haas Helmut L
Department of Physiology, Heinrich-Heine-University, Düsseldorf, Germany.
Chronobiol Int. 2006;23(1-2):63-70. doi: 10.1080/07420520500545961.
The appropriate time and place for sleep and waking are important factors for survival. Sleep and waking, rest and activity, flight and fight, feeding, and reproduction are all organized in relation to the day and night. A biological clock, the suprachiasmatic nucleus (SCN), synchronized by photic influences and other environmental cues, provides an endogenous timing signal that entrains circadian body rhythms and is complemented by a homeostatic sleep pressure factor. Cholinergic, catecholaminergic, serotonergic, and histaminergic nuclei control wakefulness and mutually interact with the SCN as well as sleep- and wake-promoting neurons in the hypothalamus to form a bistable switch that controls the timing of behavioral state transitions. Hypocretin neurons integrate circadian-photic and nutritional-metabolic influences and act as a conductor in the aminergic orchestra. Their loss causes narcolepsy, a disease conferring the inability to separate sleep and waking. Their role in appetitive behavior, stress, and memory functions is important to our understanding of addiction and compulsion.
睡眠和清醒的适宜时间与地点是生存的重要因素。睡眠与清醒、休息与活动、逃避与战斗、进食以及繁殖等一切活动都与昼夜相关。生物钟，即视交叉上核（SCN），受光影响及其他环境线索同步，提供一种内源性定时信号，该信号带动昼夜节律性身体节律，且有一个稳态睡眠压力因素作为补充。胆碱能、儿茶酚胺能、血清素能和组胺能核团控制清醒状态，并与SCN以及下丘脑促进睡眠和清醒的神经元相互作用，形成一个双稳态开关，控制行为状态转换的时间。下丘脑泌素神经元整合昼夜光信号和营养代谢影响，并在胺能系统中起指挥作用。它们的缺失会导致发作性睡病，一种使人无法区分睡眠和清醒的疾病。它们在食欲行为、应激和记忆功能中的作用对于我们理解成瘾和强迫行为很重要。
