Free-choice and no-choice high-fat diets affect striatal dopamine D2/3 receptor availability, caloric intake, and adiposity.
Different types of high-fat (HF) diets are used to study diet-induced obesity (DIO) in rodents and this has led to different phenotypes. This study assesses whether different HF diets differentially affect striatal dopamine D(2/3) receptor (DRD(2/3)) availability, as decreased striatal DRD(2/3) availability has been implicated in obesity in relation to reward deficiency for food. Thirty rats were randomized to either a free-choice HF diet (HF-choice), a premixed HF diet (HF-no-choice), or a standard chow diet for 28 days. Striatal DRD(2/3) was measured using (123)I-IBZM storage phosphor imaging at day 29. DRD(2/3) availability was significantly decreased in the dorsal striatum in the HF-choice rats compared to chow rats, but not in HF-no-choice rats. Additionally, caloric intake of the HF-choice rats was significantly higher than that of HF-no-choice rats and serum leptin and percentage abdominal fat store weight of total body weight were significantly higher in the HF-choice rats compared to chow rats. These preliminary results suggest that the choice element in HF diets, which is possibly related to the motivational aspects of eating, leads to overconsumption and to a distinct state of obesity. These results are relevant for future studies on DIO when considering choice of diet type.
Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. e.m.vandegiessen@amc.uva.nl
Elsmarieke
E
van de Giessen
Susanne E
SE
la Fleur
Kora
K
de Bruin
Wim
W
van den Brink
Jan
J
Booij
D050154:Adiposity; D000818:Animals; D001835:Body Weight; D002755:Choice Behavior / Q000502:physiology*; D003342:Corpus Striatum / Q000502:physiology*; D059305:Diet, High-Fat / Q000523:psychology*; D002149:Energy Intake / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology / Q000523:psychology; D006963:Hyperphagia / Q000503:physiopathology / Q000523:psychology; D050152:Intra-Abdominal Fat / Q000378:metabolism; D020738:Leptin / Q000097:blood; D008297:Male; D009042:Motivation; D009765:Obesity / Q000378:metabolism / Q000523:psychology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D017448:Receptors, Dopamine D2 / Q000502:physiology*; D012201:Reward
D020738:Leptin; D017448:Receptors, Dopamine D2