Modulation of sickness behavior by sleep: the role of neurochemical and neuroinflammatory pathways in mice.

Full Abstract

Activation of the immune system elicits several behavioral changes that are collectively called sickness behavior and consists in a strategy to overcome infection. Sleep deprivation can increase susceptibility to pathogens and to behavioral alterations. Thus, the present study aimed to determine how paradoxical sleep deprivation (PSD) affects the behavioral and neurochemical responses to lipopolysaccharide (LPS, potent activator of the immune response). Adult inbred mice were paradoxical sleep deprived (72 h), whereas the control group was kept in their home cages. Both groups received either an injection of saline or LPS (5, 10 or 20 microg/animal ip) before behavioral tasks and tissue collection. During the recovery sleep period, LPS provoked a strong inhibition of sleep rebound due to a suppression of paradoxical sleep. PSD increased the susceptibility of mice to LPS-induced immobility in the open field, which was capable of affecting the anxiety-like behavior also. These altered behavioral responses to LPS were accompanied by reduction in dopamine turnover within the striatum and increased expression of cyclooxygenase-2 in the cortex. The study provides some insights into how the sleep-wake cycle affects the expression of sickness behavior induced by LPS.

Author information

Author/s: Zager, Adriano (A); Andersen, Monica L (ML); Lima, Marcelo M S (MM); Reksidler, Angela B (AB); Machado, Ricardo B (RB); Tufik, Sergio (S);

Affiliation: Department of Psychobiology, Universidade Federal de São Paulo (UNIFESP-EPM), São Paulo, Brazil.

Journal and publication information

Publication Type: Journal Article; Research Support, Non-U.S. Gov't

Journal: European neuropsychopharmacology : the journal of the European College of Neuropsychopharmacology (Eur Neuropsychopharmacol), published in Netherlands. (Language: eng)

Reference: 2009-Aug; vol 19 (issue 8) : pp 589-602

Dates: Created 2009/06/29; Completed 2009/09/02;

PMID: 19394204, status: MEDLINE (last retrieval date: 9/4/2009, IMS Date: )

Sourced from the National Library of Medicine. Abstract text and other information may be subject to copyright.

External Links for this article
(including full text providers, if available):

Click Electronic Full-text Provider Links to see options for finding the electronic full text links to this article. Note there may be a subscription or fee required for access to the full text. See our FAQ for information on finding FREE full text articles.

This article may also be located in paper journal collections available in many libraries. Use the Journal and Publication Information above to find the full article.