title: Ventral hippocampal neurons inhibit postprandial energy intake.
abstract: Evidence suggests that the memory of a recently ingested meal limits subsequent intake. Given that ventral hippocampal (vHC) neurons are involved in memory and energy intake, the present experiment tested the hypothesis that vHC neurons contribute to the formation of a memory of a meal and inhibit energy intake during the postprandial period. We tested (1) whether pharmacological inactivation of vHC neurons during the period following a sucrose meal, when the memory of the meal would be undergoing consolidation, accelerates the onset of the next sucrose meal and increases intake and (2) whether sucrose intake increases vHC expression of the synaptic plasticity marker activity-regulated cytoskeletal-associated protein (Arc). Adult male Sprague-Dawley rats were trained to consume a 32% sucrose solution daily at the same time and location. On the experimental day, the rats were given intra-vHC infusions of the GABAAreceptor agonist muscimol or vehicle after they finished their first sucrose meal. Compared to vehicle infusions, postmeal intra-vHC muscimol infusions decreased the latency to the next sucrose meal, increased the amount of sucrose consumed during that meal, increased the total number of sucrose meals and the total amount of sucrose ingested. In addition, rats that consumed sucrose had higher levels of Arc expression in both vHC CA1 and CA3 subfields than cage control rats. Collectively, these findings are the first to show that vHC neurons inhibit energy intake during the postprandial period and support the hypothesis that vHC neurons form a memory of a meal and inhibit subsequent intake. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Neuroscience Institute, Georgia State University, Atlanta, Georgia.
authors.forename: Reilly C
authors.initials: RC
authors.lastname: Hannapel
authors.affiliation: Neuroscience Institute, Georgia State University, Atlanta, Georgia.
authors.forename: Yoko H
authors.initials: YH
authors.lastname: Henderson
authors.affiliation: Neuroscience Institute, Augusta Biomedical Research Corporation, Charlie Norwood VA Medical Center, 950 15th Street, Augusta, Georgia.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Nalloor
authors.affiliation: Department of Pharmacology and Toxicology, Augusta University, 1120 15th Street, CB 3526, Augusta, Georgia.|VA Research Service, Charlie Norwood VA Medical Center, 950 15th Street, Augusta, Georgia.
authors.forename: Almira
authors.initials: A
authors.lastname: Vazdarjanova
authors.affiliation: Neuroscience Institute, Georgia State University, Atlanta, Georgia.|Department of Psychology, Georgia State University, Atlanta, Georgia.
authors.forename: Marise B
authors.initials: MB
authors.lastname: Parent
mesh_terms: D000818:Animals; D002408:Catheters, Indwelling; D003598:Cytoskeletal Proteins / Q000378:metabolism; D019422:Dietary Sucrose; D002149:Energy Intake / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D009118:Muscimol / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009473:Neuronal Plasticity / Q000502:physiology; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D019518:Postprandial Period / Q000502:physiology*; D017207:Rats, Sprague-Dawley
chemical_list: D003598:Cytoskeletal Proteins; D019422:Dietary Sucrose; D058785:GABA-A Receptor Agonists; D009419:Nerve Tissue Proteins; C092069:activity regulated cytoskeletal-associated protein; D009118:Muscimol
keywords: activity regulated cytoskeletal protein; memory; muscimol; plasticity; sucrose