Do metabolic signals stimulate intake in rat pups?
During early postnatal life, rat pups make a transition from suckling to food intake independent of the dam. Accompanying this transition is the requirement for pups to independently modulate their ingestive behavior. In adult animals, one set of signals known to modulate intake is generated by administration of agents that interfere with metabolism of glucose or fats (such as mercaptoacetate [MA] or 2-deoxyglucose [2-DG]). However, demonstrations of the effects of such agents in young rats have been less robust. Recent work in our lab has focused on examining the effects of MA and methyl palmoxirate (MP) on independent ingestion in pre- and periweaning rats. In rat pups between the ages of 12 and 15 days, latencies to initiate intake independent of the dam are typically longer relative to older or younger pups. However, the latency with which 12- and 15-day-old pups initiate independent ingestion is reduced following administration of MA. Further, MA produces physiological changes consistent with a change in the oxidation of fatty acids in 12- and 15-day-old pups, and similar physiological changes are produced during moderate periods of food deprivation in pups at the same ages. Thus, signals related to changes in the oxidation of fatty acids normally produced by moderate food deprivation in periweaning rats may provide a fundamental signal involved in the onset and modulation of intake independent of the dam.
Swithers
Susan E
SE
Department of Psychological Sciences, Purdue University, 703 Third Street, West Lafayette, IN 47907-2004, USA. swithers@psych.purdue.edu
D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose / Q000378:metabolism; D003847:Deoxyglucose / Q000494:pharmacology; D004041:Dietary Fats / Q000378:metabolism; D004435:Eating / Q000187:drug effects / Q000502:physiology*; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology*; D004852:Epoxy Compounds / Q000494:pharmacology; D005227:Fatty Acids / Q000378:metabolism; D005246:Feedback / Q000502:physiology*; D005260:Female; D008297:Male; D011247:Pregnancy; D011422:Propionates / Q000494:pharmacology; D051381:Rats; D013864:Thioglycolates / Q000494:pharmacology; D014886:Weaning
D001786:Blood Glucose; D004041:Dietary Fats; D004852:Epoxy Compounds; D005227:Fatty Acids; D011422:Propionates; D013864:Thioglycolates; C017487:2-mercaptoacetate; D003847:Deoxyglucose; C017522:methyl 2-tetradecylglycidate