title: Fos protein expression in the nucleus of the solitary tract in response to intestinal nutrients in awake rats.
abstract: Nutrients in the intestine inhibit food intake via an action on the vagal afferent pathway. The aim of the present study was to use immunochemical detection of Fos protein-like immunoreactivity (FLI) in the brainstem to trace the neuronal pathways activated by intestinal nutrients. Perfusion of the intestine of awake rats via an indwelling duodenal catheter with iso-osmotic mannitol, hydrochloric acid or casein hydrolysate had no effect on the number of FLI neurons in the nucleus of the solitary tract (NTS). Lipid emulsion (20%) and 2.7 M glucose significantly increased the number of immunopositive cells in the NTS. There was a significant increase in the number of immunopositive cells from caudal to rostral NTS. Nutrients effective at decreasing food intake (carbohydrate and fat) produced significant increases in Fos-like immunopositive cells in the NTS.
authors.affiliation: Department of Medicine, CURE-VA/UCLA Gastroenteric Biology Center 90073.
authors.forename: T T
authors.initials: TT
authors.lastname: Zittel
authors.forename: R
authors.initials: R
authors.lastname: De Giorgio
authors.forename: C
authors.initials: C
authors.lastname: Sternini
authors.forename: H E
authors.initials: HE
authors.lastname: Raybould
mesh_terms: D000818:Animals; D004040:Dietary Carbohydrates / Q000378:metabolism*; D004041:Dietary Fats / Q000378:metabolism*; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000166:cytology / Q000378:metabolism*; D008297:Male; D009419:Nerve Tissue Proteins / Q000032:analysis*; D009474:Neurons / Q000737:chemistry; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017552:Solitary Nucleus / Q000737:chemistry*
chemical_list: D004040:Dietary Carbohydrates; D004041:Dietary Fats; D009419:Nerve Tissue Proteins; D016760:Proto-Oncogene Proteins c-fos