NREM-promoting system

During the last decade, research lent support to the idea that three interacting neuronal systems (a wake-promoting system, a NREM-promoting system and a REM-... 

Disturbances of the NREM-promoting system the process S deficiency theory of depression... 

The present section brings some support to the notion that a deficient NREM-promoting system may underlie sleep disturbances in depressive disorder. These arguments are not at variance with those of the preceding section since hypotheses of hyperarousal and of Process S deficiency are not mutually exclusive both together or separately could explain sleep continuity disturbances and SWS deficit observed in depressive illness. 

Intracerebral or systemic administration of IL-1 P enhances NREM sleep in mice, rats, rabbits, cats, monkeys, and humans (reviewed in Refs. 40,46), and TNF-a promotes NREM sleep in rabbits, mice, rats, and sheep (reviewed in Refs. 40,46). Both NREM sleep time and intensity (EEG slow-wave activity) increase after IL-1 3 or TNF-a. In rats and cats, only low doses of IL-1 stimulate NREM sleep. In contrast, higher doses decrease NREM sleep, perhaps owing to IL-ip-induced stimulation of corticotropin-releasing hormone (CRH), which is known to suppress NREM sleep (55,56). A correlation is observed between plasma TNF-a concentrations and sleepiness or fatigue in a number of clinical conditions. Thus, TNF-a is... 

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