Vagal and splanchnic afferents are not necessary for the anorexia produced by peripheral IL-1beta, LPS, and MDP.
We investigated the extrinsic gut neural mediation of the suppression of food intake in male Sprague-Dawley rats induced by peripheral intraperitoneal administration of 2 microg/kg interleukin-1beta (IL-1beta), 100 microg/kg bacterial lipopolysaccharide (LPS), and 2 mg/kg muramyl dipeptide (MDP). Food intake during the first 3 and 6 h of the dark cycle was measured in rats with subdiaphragmatic vagal deafferentation (n = 9), celiac superior mesenteric ganglionectomy (n = 9), combined vagotomy and ganglionectomy (n = 9), and sham deafferentation (n = 9). IL-1beta, LPS, and MDP suppressed food intake at 3 and 6 h in all surgical groups. The results demonstrate that neither vagal nor nonvagal afferent nerves from the upper gut are necessary for the feeding-suppressive effects of intraperitoneal IL-1beta, LPS, or MDP in the rat and suggest that peripheral administration of immunomodulators produces anorexia via a humoral pathway.
Institute for Animal Sciences, Physiology and Animal Husbandry, Swiss Federal Institute of Technology, 8092 Zurich, Switzerland.
M H
MH
Porter
B J
BJ
Hrupka
W
W
Langhans
G J
GJ
Schwartz
D000119:Acetylmuramyl-Alanyl-Isoglutamine / Q000008:administration & dosage / Q000494:pharmacology*; D000344:Afferent Pathways / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D000855:Anorexia / Q000139:chemically induced / Q000503:physiopathology*; D002766:Cholecystokinin / Q000494:pharmacology*; D002149:Energy Intake / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology*; D015171:Ganglionectomy; D007274:Injections, Intraperitoneal; D007375:Interleukin-1 / Q000008:administration & dosage / Q000494:pharmacology*; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013153:Splanchnic Nerves / Q000502:physiology*; D014628:Vagotomy; D014630:Vagus Nerve / Q000502:physiology*
D007375:Interleukin-1; D008070:Lipopolysaccharides; D000119:Acetylmuramyl-Alanyl-Isoglutamine; D002766:Cholecystokinin