Effect of fenfluramine on caloric intake and macronutrient selection in Lou/c rats during aging.
Previous studies have shown a shift of preferences from carbohydrate to fat and a decrease in protein intake in self-selected Lou/c rats with advancing age. This study investigated a potential neurochemical mechanism underlying age-related modifications by evaluating the effects of fenfluramine (dl-F), a drug that enhances 5-HT release and blocks its re-uptake by presynaptic terminals, on macronutrient selection. The drug dl-F (1.5 and 3mg/kg s.c.) induces a dose-related hypophagia with the oldest animals being the most sensitive. The main decrease is in fat consumption with minor changes in carbohydrate and protein consumptions. Young, but not old animals, compensate during the day the nocturnal intake decrease induced by dl-F. The plasma concentration of dexfenfluramine (d-F) was higher as the rats aged. The icv administrations of dl-F induced a caloric intake decrease in the oldest groups and a differential effect on protein intake between old and young rats. Metergoline induced a partial reversion of dl-F effect on food intake but this effect was not age related. These data suggest a possible implication of serotoninergic system in modifications of food behavior during aging. However, further studies are needed.
Jourdan
Didier
D
Laboratoire de Neuroendocrinologie du Vieillissement, Complexe Scientifique des Cézeaux, Université Blaise Pascal, 63 177 Aubière Cedex, France. didier.jourdan@univ-bpclermont.fr
Piec
Isabelle
I
Gaulier
Jean-Michel
JM
Lacassie
Eric
E
Alliot
Josette
J
D000375:Aging / Q000187:drug effects* / Q000502:physiology; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D020372:Dexfenfluramine / Q000097:blood / Q000494:pharmacology; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D018491:Dopamine Agonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D002149:Energy Intake / Q000187:drug effects* / Q000502:physiology; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology; D005277:Fenfluramine / Q000097:blood / Q000494:pharmacology*; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology; D007276:Injections, Intraventricular; D008297:Male; D008711:Metergoline / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D017367:Selective Serotonin Reuptake Inhibitors / Q000097:blood / Q000494:pharmacology*; D013997:Time Factors
D020372:Dexfenfluramine; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D018491:Dopamine Agonists; D005277:Fenfluramine; D008711:Metergoline; D017367:Selective Serotonin Reuptake Inhibitors