title: Intraperitoneal CCK and fourth-intraventricular Apo AIV require both peripheral and NTS CCK1R to reduce food intake in male rats.
abstract: Apolipoprotein AIV (Apo AIV) and cholecystokinin (CCK) are secreted in response to fat consumption, and both cause satiation via CCK 1 receptor (CCK-1R)-containing vagal afferent nerves to the nucleus of the solitary tract (NTS), where Apo AIV is also synthesized. Fasted male Long-Evans rats received ip CCK-8 or fourth-ventricular (i4vt) Apo AIV alone or in combination. Food intake and c-Fos proteins (a product of the c-Fos immediate-early gene) were assessed. i4vt Apo AIV and/or ip CCK at effective doses reduced food intake and activated c-Fos proteins in the NTS and hypothalamic arcuate nucleus and paraventricular nucleus. Blockade of the CCK-1R by i4vt lorglumide adjacent to the NTS attenuated the satiating and c-Fos-stimulating effects of CCK and Apo AIV, alone or in combination. Maintenance on a high-fat diet (HFD) for 10 weeks resulted in weight gain and attenuation of both the behavioral and c-Fos responses to a greater extent than occurred in low-fat diet-fed and pair-fed HFD animals. These observations suggest that NTS Apo AIV or/and peripheral CCK requires vagal CCK-1R signaling to elicit satiation and that maintenance on a HFD reduces the satiating capacity of these 2 signals.
authors.affiliation: Departments of Pathology and Laboratory Medicine (C.C.L., W.S.D., S.K.H., M.G., A.L., P.T.) and Psychiatry and Behavioral Neuroscience (S.C.W.), Metabolic Diseases Institute, University of Cincinnati, Cincinnati, Ohio 45237-0507.
authors.forename: Chunmin C
authors.initials: CC
authors.lastname: Lo
authors.forename: W Sean
authors.initials: WS
authors.lastname: Davidson
authors.forename: Stephanie K
authors.initials: SK
authors.lastname: Hibbard
authors.forename: Maria
authors.initials: M
authors.lastname: Georgievsky
authors.forename: Alexander
authors.initials: A
authors.lastname: Lee
authors.forename: Patrick
authors.initials: P
authors.lastname: Tso
authors.forename: Stephen C
authors.initials: SC
authors.lastname: Woods
mesh_terms: D000818:Animals; D001054:Apolipoproteins A / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D001067:Appetite Depressants / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use; D001069:Appetite Regulation / Q000187:drug effects; D019167:Appetite Stimulants / Q000008:administration & dosage / Q000494:pharmacology; D001070:Appetitive Behavior / Q000187:drug effects; D001522:Behavior, Animal / Q000187:drug effects; D002766:Cholecystokinin / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000378:metabolism*; D059305:Diet, High-Fat / Q000009:adverse effects; D006727:Hormone Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D057967:Infusions, Intraventricular; D007274:Injections, Intraperitoneal; D008297:Male; D009419:Nerve Tissue Proteins / Q000008:administration & dosage / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009475:Neurons, Afferent / Q000187:drug effects / Q000378:metabolism*; D009765:Obesity / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism; D051381:Rats; D020318:Rats, Long-Evans; D043886:Receptor, Cholecystokinin A / Q000819:agonists / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000494:pharmacology; D012844:Sincalide / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology; D017552:Solitary Nucleus / Q000187:drug effects / Q000378:metabolism*
chemical_list: C090019:8-sulfocholecystokinin octapeptide; D001054:Apolipoproteins A; D001067:Appetite Depressants; D019167:Appetite Stimulants; D006727:Hormone Antagonists; D009419:Nerve Tissue Proteins; D043886:Receptor, Cholecystokinin A; D011994:Recombinant Proteins; C022205:apolipoprotein A-IV; D002766:Cholecystokinin; D012844:Sincalide