title: Genetic predisposition to obesity affects behavioural traits including food reward and anxiety-like behaviour in rats.
abstract: Here we sought to define behavioural traits linked to anxiety, reward, and exploration in different strains of rats commonly used in obesity research. We hypothesized that genetic variance may contribute not only to their metabolic phenotype (that is well documented) but also to the expression of these behavioural traits. Rat strains that differ in their susceptibility to develop an obese phenotype (Sprague-Dawley, Obese Prone, Obese Resistant, and Zucker rats) were exposed to a number of behavioural tests starting at the age of 8 weeks. We found a similar phenotype in the obesity susceptible models, Obese Prone and Zucker rats, with a lower locomotor activity, exploratory activity, and higher level of anxiety-like behaviour in comparison to the leaner Obese Resistant strain. We did not find evidence that rat strains with a genetic predisposition to obesity differed in their ability to experience reward from chocolate (in a condition place preference task). However, Zucker rats show higher motivated behaviour for sucrose compared to Obese Resistant rats when the effort required to obtain palatable food is relatively low. Together our data demonstrate that rat strains that differ in their genetic predisposition to develop obesity also differ in their performance in behavioural tests linked to anxiety, exploration, and reward and that these differences are independent of body weight. We conclude that genetic variations which determine body weight and the aforementioned behaviours co-exist but that future studies are required to identify whether (and which) common genes are involved.
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Department of Experimental Diabetology, German Institute of Human Nutrition Potsdam-Rehbruecke, Nuthetal, Germany; German Center for Diabetes Research (DZD), München-Neuherberg, Germany.
authors.forename: Heike
authors.initials: H
authors.lastname: Vogel
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Kraemer
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Cristina
authors.initials: C
authors.lastname: Rabasa
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Kaisa
authors.initials: K
authors.lastname: Askevik
authors.affiliation: Brain Center Rudolf Magnus, Department of Translational Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands.
authors.forename: Roger A H
authors.initials: RAH
authors.lastname: Adan
authors.affiliation: Department of Physiology/Endocrinology, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden. Electronic address: suzanne.dickson@neuro.gu.se.
authors.forename: Suzanne L
authors.initials: SL
authors.lastname: Dickson
mesh_terms: D000818:Animals; D001007:Anxiety / Q000235:genetics / Q000378:metabolism; D001522:Behavior, Animal / Q000502:physiology; D001835:Body Weight / Q000235:genetics / Q000502:physiology; D003213:Conditioning, Psychological / Q000502:physiology; D005106:Exploratory Behavior / Q000502:physiology; D005502:Food; D020022:Genetic Predisposition to Disease; D008297:Male; D009042:Motivation / Q000235:genetics / Q000502:physiology; D009043:Motor Activity; D009714:Nucleus Accumbens / Q000378:metabolism; D009765:Obesity / Q000235:genetics* / Q000378:metabolism / Q000523:psychology*; D010641:Phenotype; D017207:Rats, Sprague-Dawley; D011924:Rats, Zucker; D012201:Reward; D013045:Species Specificity
keywords: Activity; Anxiety; Food reward; Genetic predisposition; Obesity