Infra-additivity of combined treatments with selective D1 and D2 receptor antagonists for inhibiting sucrose reinforcement.
Selective antagonists of either the D1 receptor (SCH 23390) or of the D2 receptor (raclopride) produce a dose-related inhibition of sucrose sham feeding in the rat. We investigated the effect of combined treatments with these antagonists on sucrose sham feeding and observed infra-additivity of inhibition across a range of doses. On the basis of this observed occlusive relationship, we conclude that the relevant D1 and D2 receptor mechanisms mediating sweet taste reward do not function independently.
Schneider
L H
LH
Department of Psychiatry, New York Hospital-Cornell Medical Center, Edward W. Bourne Behavioral Research Lab, White Plains 10605.
Watson
C A
CA
Gibbs
J
J
Smith
G P
GP
D000818:Animals; D001552:Benzazepines / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D005247:Feeding Behavior / Q000187:drug effects*; D008297:Male; D020891:Raclopride; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012054:Reinforcement, Psychology; D012201:Reward; D012457:Salicylamides / Q000494:pharmacology*; D013395:Sucrose
D001552:Benzazepines; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012457:Salicylamides; D020891:Raclopride; D013395:Sucrose