title: Role of capsaicin-sensitive peripheral sensory neurons in anorexic responses to intravenous infusions of cholecystokinin, peptide YY-(3-36), and glucagon-like peptide-1 in rats.
abstract: Cholecystokinin (CCK)-induced suppression of feeding is mediated by vagal sensory neurons that are destroyed by the neurotoxin capsaicin (CAP). Here we determined whether CAP-sensitive neurons mediate anorexic responses to intravenous infusions of gut hormones peptide YY-(3-36) [PYY-(3-36)] and glucagon-like peptide-1 (GLP-1). Rats received three intraperitoneal injections of CAP or vehicle (VEH) in 24 h. After recovery, non-food-deprived rats received at dark onset a 3-h intravenous infusion of CCK-8 (5, 17 pmol·kg⁻¹·min⁻¹), PYY-(3-36) (5, 17, 50 pmol·kg⁻¹·min⁻¹), or GLP-1 (17, 50 pmol·kg⁻¹·min⁻¹). CCK-8 was much less effective in reducing food intake in CAP vs. VEH rats. CCK-8 at 5 and 17 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 39 and 71% in VEH rats and 7 and 18% in CAP rats. In contrast, PYY-(3-36) and GLP-1 were similarly effective in reducing food intake in VEH and CAP rats. PYY-(3-36) at 5, 17, and 50 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 15, 33, and 70% in VEH rats and 13, 30, and 33% in CAP rats. GLP-1 at 17 and 50 pmol·kg⁻¹·min⁻¹ reduced food intake during the 3-h infusion period by 48 and 60% in VEH rats and 30 and 52% in CAP rats. These results suggest that anorexic responses to PYY-(3-36) and GLP-1 are not primarily mediated by the CAP-sensitive peripheral sensory neurons (presumably vagal) that mediate CCK-8-induced anorexia.
authors.affiliation: Veterans Affairs Research Service, Veterans Affairs Nebraska Western Iowa Health Care System, Omaha, Nebraska; and Department of Biomedical Sciences, Creighton University, Omaha, Nebraska rogerreidelberger@creighton.edu.
authors.forename: Roger
authors.initials: R
authors.lastname: Reidelberger
authors.affiliation: Veterans Affairs Research Service, Veterans Affairs Nebraska Western Iowa Health Care System, Omaha, Nebraska; and Department of Biomedical Sciences, Creighton University, Omaha, Nebraska.
authors.forename: Alvin
authors.initials: A
authors.lastname: Haver
authors.affiliation: Department of Biomedical Sciences, Creighton University, Omaha, Nebraska.
authors.forename: Krista
authors.initials: K
authors.lastname: Anders
authors.affiliation: Department of Biomedical Sciences, Creighton University, Omaha, Nebraska.
authors.forename: Bettye
authors.initials: B
authors.lastname: Apenteng
mesh_terms: D000818:Animals; D000855:Anorexia / Q000378:metabolism / Q000503:physiopathology* / Q000517:prevention & control; D001522:Behavior, Animal / Q000187:drug effects; D002211:Capsaicin / Q000008:administration & dosage / Q000633:toxicity; D002766:Cholecystokinin / Q000008:administration & dosage / Q000378:metabolism*; D004195:Disease Models, Animal; D002149:Energy Intake / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D052216:Glucagon-Like Peptide 1 / Q000008:administration & dosage / Q000378:metabolism; D007262:Infusions, Intravenous; D007274:Injections, Intraperitoneal; D007413:Intestinal Mucosa / Q000187:drug effects / Q000294:innervation* / Q000378:metabolism / Q000503:physiopathology; D007421:Intestine, Small / Q000187:drug effects / Q000294:innervation* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D009443:Neuritis / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology*; D009475:Neurons, Afferent / Q000187:drug effects / Q000378:metabolism*; D010446:Peptide Fragments / Q000008:administration & dosage / Q000378:metabolism*; D019894:Peptide YY / Q000008:administration & dosage / Q000378:metabolism; D051381:Rats; D014630:Vagus Nerve / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology; D020421:Vagus Nerve Diseases / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology
chemical_list: D010446:Peptide Fragments; C410885:cholecystokinin 8; D019894:Peptide YY; C061785:peptide YY (3-36); D052216:Glucagon-Like Peptide 1; D002766:Cholecystokinin; D002211:Capsaicin
keywords: gut hormones; intravenous infusion; satiety; vagus