Melatonin reduces anxiety induced by lipopolysaccharide in the rat

Neurosci Lett. 2001 Jul 6;307(1):57-60. doi: 10.1016/s0304-3940(01)01930-9.

Abstract

In male Sprague-Dawley rats intraperitoneal (i.p.) injection of Escherichia coli lipopolysaccharide (0.25, 0.50 and 1 mg/kg) increased anxiety levels. This effect was reversed by a prior, concomitant, and subsequent i.p. treatment with melatonin (4 and 6 mg/kg). As the effects of melatonin upon the actions induced by lipopolysaccharide were reversed by the melatonin receptor antagonist luzindole (30 and 60 mg/kg, i.p.), we argued that they are, but not only, melatonin receptor mediated. These findings, in accordance with our previous works, suggest that melatonin could be useful in the treatment of sickness behaviour associated with systemic infection diseases or as adjuvant in the anti-anxiety therapy.

MeSH terms

  • Animals
  • Anxiety / chemically induced
  • Anxiety / drug therapy*
  • Anxiety / physiopathology
  • Bacterial Infections / complications
  • Bacterial Infections / metabolism
  • Bacterial Infections / physiopathology
  • Behavior, Animal / drug effects
  • Behavior, Animal / physiology
  • Brain / drug effects*
  • Brain / metabolism
  • Circadian Rhythm / drug effects
  • Circadian Rhythm / physiology
  • Dose-Response Relationship, Drug
  • Drug Interactions / physiology*
  • Endotoxins / adverse effects
  • Endotoxins / metabolism
  • Lipopolysaccharides / pharmacology*
  • Male
  • Maze Learning / drug effects
  • Maze Learning / physiology
  • Melatonin / metabolism
  • Melatonin / pharmacology*
  • Rats
  • Rats, Sprague-Dawley / metabolism
  • Rats, Sprague-Dawley / psychology*
  • Receptors, Cell Surface / agonists*
  • Receptors, Cell Surface / antagonists & inhibitors
  • Receptors, Cell Surface / metabolism
  • Receptors, Cytoplasmic and Nuclear / agonists*
  • Receptors, Cytoplasmic and Nuclear / antagonists & inhibitors
  • Receptors, Cytoplasmic and Nuclear / metabolism
  • Receptors, Melatonin
  • Tryptamines / pharmacology

Substances

  • Endotoxins
  • Lipopolysaccharides
  • Receptors, Cell Surface
  • Receptors, Cytoplasmic and Nuclear
  • Receptors, Melatonin
  • Tryptamines
  • luzindole
  • Melatonin