title: Overexpression of neuropeptide Y in the dorsomedial hypothalamus increases trial initiation but does not significantly alter concentration-dependent licking to sucrose in a brief-access taste test.
abstract: Evidence in the literature raises the possibility that alterations in neuropeptide Y (NPY) in the dorsomedial hypothalamus (DMH) may contribute to hyperphagia leading to body weight gain. Previously, we have shown that compared to AAVGFP controls, adeno-associated virus (AAV)-mediated overexpression of NPY in the DMH of lean rats resulted in significantly higher body weight gain that was attributed to increased food intake, and this was further exacerbated by a high-fat diet. Here, we tested AAVNPY and AAVGFP control rats in a brief-access taste procedure (10-s trials, 30-min sessions) to an array of sucrose concentrations under ad libitum and partial food and water access conditions. The test allows for some segregation of the behavioral components by providing a measure of trial initiation (appetitive) and unconditioned licks at each concentration (consummatory). Consistent with previous findings suggesting that NPY has a primary effect on appetitive function, overexpression of DMH NPY did not significantly alter concentration-dependent licking response to sucrose but when tested in a non-restricted food and water schedule, AAVNPY rats initiated significantly more sucrose trials compared to AAVGFP controls in a brief-access taste test.
authors: Department of Psychiatry and Behavioral Sciences, School of Medicine, Johns Hopkins University, Ross 615, 720 Rutland Ave, Baltimore, MD 21205, USA. yadatree@jhmi.edu
authors: Yada
authors: Y
authors: Treesukosol
authors: Sheng
authors: S
authors: Bi
authors: Timothy H
authors: TH
authors: Moran
mesh_terms: D000818:Animals; D001066:Appetite / Q000502:physiology; D003216:Conditioning, Operant / Q000187:drug effects; D003259:Consummatory Behavior / Q000187:drug effects; D003627:Data Interpretation, Statistical; D000229:Dependovirus / Q000235:genetics; D004302:Dorsomedial Hypothalamic Nucleus / Q000378:metabolism*; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins; D017403:In Situ Hybridization; D008297:Male; D009478:Neuropeptide Y / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013395:Sucrose; D013649:Taste / Q000235:genetics / Q000502:physiology*; D014868:Water Deprivation
chemical_list: D009478:Neuropeptide Y; D049452:Green Fluorescent Proteins; D013395:Sucrose