From a physiological perspective the sleep-wake cycle can be envisioned as a sequence of three physiological states, identified by a particular homeostatic patent: wakefulness, non-rapid eye movement (NREM) or slow sleep, and REM sleep. These three physiological states are defined by a particular neuroendocrine-immune profile that regulates the immune system response. This review discusses the physiological basis of such a control of the immune system at different sleep stages, as well as the manner in which humoral signals (cytokines) produced by immunocompetent cells modify the mechanisms of sleep.
Keywords: Circadian rhythms, cytokines, melatonin, neuroimmunology, sleep, non-rapid eye movement, rapid eye movement, neuroendocrine, IL-1, TNF-a