Selective slow-wave sleep deprivation influences blood serotonin profiles and serum melatonin concentrations in healthy subjects

Abstract

Internal desynchronization in circadian rhythms provoked by shift work in susceptible individuals may interfere with the time-keeping system and circadian rhythms of the sleep-wake cycle, vital signs, neurotransmitters, and hormone concentrations in blood. It may lead to an abnormal relationship between the central circadian pacemaker and higher cognitive brain centers causing a higher frequency of health complaints among nightshift workers than among day workers (Moore-Ede et al 1982). It has been speculated that continued desynchronization precipitates a homeostatic imbalance which may result in depressive illness; thus depression has been hypothesized to be a disorder of time-keeping (van Cauter and Turek 1986; Aschoff 1981; Wehr and Goodwin 1983). Serotonin and melatonin are neuromodulators involved in the regulation of sleep and circadian rhythmicity. Serotonin's role in sleep regulation has been shown by Koella (1984), Borbely et al (1980), Matussek and Patschke (1963), Wauquier and Dugovic (1990), and others, although it is still debated whether a change in serotonin turnover is actually associated with insomnia. The suprachiasmatic nucleus which accommodates the internal clock is innervated with serotonergic neurons, and serotonin is the