title: Participation of α2 -adrenoceptors in sodium appetite inhibition during sickness behaviour following administration of lipopolysaccharide.
abstract: Sickness behaviour, a syndrome characterized by a general reduction in animal activity, is part of the active-phase response to fight infection. Lipopolysaccharide (LPS), an effective endotoxin to model sickness behaviour, reduces thirst and sodium excretion, and increases neurohypophysial secretion. Here we review the effects of LPS on thirst and sodium appetite. Altered renal function and hydromineral fluid intake in response to LPS occur in the context of behavioural reorganization, which manifests itself as part of the syndrome. Recent data show that, in addition to its classical effect on thirst, non-septic doses of LPS injected intraperitoneally produce a preferential inhibition of intracellular thirst versus extracellular thirst. Moreover, LPS also reduced hypertonic NaCl intake in sodium-depleted rats that entered a sodium appetite test. Antagonism of α2 -adrenoceptors abolished the effect of LPS on sodium appetite. LPS and cytokine transduction potentially recruit brain noradrenaline and α2 -adrenoceptors to control sodium appetite and sickness behaviour.
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
authors.forename: Laurival A
authors.initials: LA
authors.lastname: De Luca
authors.affiliation: Department of Physiology, ABC Medical School, Santo André, São Paulo, Brazil.
authors.forename: Roberto L
authors.initials: RL
authors.lastname: Almeida
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
authors.forename: Richard B
authors.initials: RB
authors.lastname: David
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: de Paula
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
authors.forename: Carina A F
authors.initials: CA
authors.lastname: Andrade
authors.affiliation: Department of Physiology and Pathology, School of Dentistry, São Paulo State University - UNESP, Araraquara, São Paulo, Brazil.
authors.forename: José V
authors.initials: JV
authors.lastname: Menani
mesh_terms: D000818:Animals; D001066:Appetite; D055809:Illness Behavior; D008070:Lipopolysaccharides / Q000633:toxicity; D018341:Receptors, Adrenergic, alpha-2 / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D014882:Water-Electrolyte Balance
chemical_list: D008070:Lipopolysaccharides; D018341:Receptors, Adrenergic, alpha-2; D012964:Sodium