title: Microinjections of dopaminergic agents in the nucleus accumbens affect ethanol consumption but not palatability.
abstract: It was determined whether ethanol palatability in rats could be changed by manipulating the reinforcement experienced during limited access consumption. During the first 3 days of the experiment, initial taste reactivity (TR) testing to distilled water (1 day) and 10% alcohol (2 days) was performed. Following the establishment of baseline TR, separate groups of animals received bilateral microinjections (0.5 microl/side) into the nucleus accumbens of either the nonspecific dopamine agonist d-amphetamine sulfate (20 microg, n = 10), the D(2) antagonist raclopride (1.0 microg, n = 8), or physiological saline (n = 5). The injections occurred at the same time each day for 5 consecutive days. Five minutes after the microinjection, the fluid-deprived rats were given 30-min access to 10% ethanol. Over the 3 days following drug administration, TR to distilled water and 10% alcohol was repeated. After this, the rats were once again given 30 min of access to 10% ethanol for 5 consecutive days, but without drug microinjection prior to alcohol access. A final TR exposure (the same as the others) was performed over the final 3 days of the study. Both raclopride and d-amphetamine administration produced reductions in ethanol consumption (in comparison to saline treatment). However, treatment with d-amphetamine and raclopride during ethanol consumption did not cause significant, conditioned changes in palatability as measured by the taste reactivity procedure. These results suggest that dopamine plays a role in the motivation to consume ethanol but this neurotransmitter is not involved in evaluating its incentive value.
authors.affiliation: Kansas State University, Department of Psychology, Manhattan, KS, 66506 USA.
authors.forename: H J
authors.initials: HJ
authors.lastname: Kaczmarek
authors.forename: S W
authors.initials: SW
authors.lastname: Kiefer
mesh_terms: D000428:Alcohol Drinking / Q000503:physiopathology*; D000818:Animals; D003913:Dextroamphetamine / Q000008:administration & dosage; D015259:Dopamine Agents / Q000008:administration & dosage*; D018491:Dopamine Agonists / Q000008:administration & dosage; D018492:Dopamine Antagonists / Q000008:administration & dosage; D008297:Male; D008845:Microinjections; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000502:physiology*; D020891:Raclopride / Q000008:administration & dosage; D051381:Rats; D012054:Reinforcement, Psychology; D013649:Taste / Q000187:drug effects*
chemical_list: D015259:Dopamine Agents; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D020891:Raclopride; D003913:Dextroamphetamine