Comparison of C57BL/6 and DBA/2 mice in food motivation and satiety.
Demand functions describe the relationship between the consumption of a commodity and its mean or unit price. In the first experiment, we analyzed food demand in two strains of mice (C57BL/6 and DBA/2) that differ on several behavioral dimensions, but have not been examined extensively for differences in feeding and meal patterns. Mice worked for food pellets in a continuous access closed economy in which total intake and meal patterns could be measured. A series of fixed (FUP), variable (VUP), and progressive (PUP) unit price schedules were imposed. Under all schedules, DBA/2 mice consumed significantly more food than C57BL/6, a difference that was not attributable to disparity in body weight or weight gain. The higher intake of DBA/2 mice was due predominantly to larger meal size compared with C57BL/6, with no strain difference in meal frequency. In a second experiment, strain differences in meal size were not found to correlate with anorectic sensitivity to cholecystokinin (CCK) administration, or with c-Fos expression induced by CCK in PVN, AP and NTS. Thus, DBA/2 mice were motivated to sustain a higher daily food intake and meal size than C57BL/6 under the range of demand costs employed in the present work, but this strain difference is unlikely to be due to CCK action or responsiveness.
Atalayer
Deniz
D
Department of Psychology, University of Florida, Gainesville, FL 32611-2250, USA.
Rowland
Neil E
NE
D000704:Analysis of Variance; D000818:Animals; D031608:Area Postrema / Q000187:drug effects / Q000378:metabolism; D002766:Cholecystokinin / Q000494:pharmacology; D003216:Conditioning, Operant / Q000502:physiology; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology*; D005786:Gene Expression Regulation / Q000187:drug effects; D051379:Mice; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D009042:Motivation / Q000187:drug effects; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D012055:Reinforcement Schedule; D012527:Satiation / Q000187:drug effects / Q000502:physiology*; D012686:Septal Nuclei / Q000187:drug effects / Q000378:metabolism; D013045:Species Specificity
D016760:Proto-Oncogene Proteins c-fos; D002766:Cholecystokinin