Interactive effects of peripheral and central administration of LPS with inhibition of CRF receptors on food intake in neonatal chicks

Anorexia is a part of the acute phase response (APR). Lipopolysaccharide (LPS) is frequently used to mimic APR and induces anorexia. The mechanism underlying anorexia associated with APR in chicks is not well understood. In the present study, the possible involvement of corticotrophin-releasing factor (CRF) on anorexic effects of LPS in neonatal chicks was investigated. For this aim, different doses of LPS were administrated via both intracerebroventricular (ICV) and intraperitoneal (IP) routes in order to assess its effects on chick’s food intake. Subsequently, the effect of ICV injection of astressin, a CRF receptor antagonist, on anorexia induced by ICV and IP administration of LPS was investigated. Food intake was significantly decreased following either central or systemic administration of LPS. ICV co -injection of astressin and LPS significantly diminished anorexic effects of central LPS. However, anorexia induced by peripheral LPS was not attenuated by central injection of astressin. These data indicated that the brain CRF receptors are involved in central LPS-induced anorexia in chicks.

Keywords:

Lipopolysaccharide , Acute illness anorexia , Corticotrophin-releasing factor , Neonatal chicks