Effects of d- and l-amphetamine on food intake: evidence for a dopaminergic substrate.
The present experiment examined the effects of d- and l-amphetamine on the intake of sugar, sweetened rat chow and unsweetened rat chow in free feeding rats. Rats were injected IP with 4 doses of d- or l-amphetamine (0.0, 0.125, 0.50 and 2.00 mg/kg). Regardless of drug condition, animals were found to prefer sugar over sweetened or unsweetened chow. d-Amphetamine significantly increased food intake at 0.125 and 0.50 mg/kg doses but not at 2.00 mg/kg. l-Amphetamine had no significant effects at any dose. Further, d-amphetamine significantly increased sugar intake but not sweetened or unsweetened chow. Since d- and l-amphetamine are equipotent at releasing noradrenaline, while d-amphetamine is 2 to 5 times more potent at releasing dopamine, the results suggest that d-amphetamine-induced feeding is associated with activation of a dopaminergic substrate.
Evans
K R
KR
Department of Psychology, University of Toronto, Ontario, Canada.
Vaccarino
F J
FJ
D000661:Amphetamine / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D002241:Carbohydrates; D003913:Dextroamphetamine / Q000494:pharmacology*; D004298:Dopamine / Q000502:physiology*; D004435:Eating / Q000187:drug effects*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013549:Sweetening Agents
D002241:Carbohydrates; D013549:Sweetening Agents; D000661:Amphetamine; D003913:Dextroamphetamine; D004298:Dopamine