Mice lacking dopamine D1 receptors express normal lithium chloride-induced conditioned taste aversion for salt but not sucrose.
Conditioned taste aversion (CTA), is a form of Pavlovian learning wherein a novel flavour is powerfully associated with subsequent feelings of illness, and is afterwards avoided. In rats, pharmacological blockade of dopamine D1 receptors has been reported to prevent the expression of a CTA to the sweet taste of sucrose or saccharine. We used genetically modified mice to determine whether dopamine D1 receptors are necessary for the expression of a CTA. Food-deprived mice lacking the dopamine D1 receptor (D1r-/-) did not express a LiCl-induced (125 or 254 mg/kg) CTA to the sweet taste of 0.5 m sucrose, in agreement with previous pharmacological studies. However, water-deprived D1r-/- mice did express normal LiCl-induced (40, 150 and 254 mg/kg) CTA to a salty taste (0.2 m NaCl). Our results suggest that activation of D1 receptors might contribute to the strength of an aversive gustatory association, but might not be required for the formation of a CTA in general.
Cannon
Claire Matson
CM
Department of Biochemistry and Howard Hughes Medical Institute, University of Washington, Seattle, WA 98195-7370, USA. caesia@u.washington.edu
Scannell
Christopher A
CA
Palmiter
Richard D
RD
D000818:Animals; D018692:Antimanic Agents / Q000494:pharmacology*; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology*; D003213:Conditioning, Psychological / Q000187:drug effects / Q000502:physiology; D005518:Food Preferences / Q000187:drug effects / Q000502:physiology*; D018021:Lithium Chloride / Q000494:pharmacology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008817:Mice, Mutant Strains; D017447:Receptors, Dopamine D1 / Q000235:genetics*; D012492:Salts; D013395:Sucrose; D013649:Taste
D018692:Antimanic Agents; D017447:Receptors, Dopamine D1; D012492:Salts; D013395:Sucrose; D018021:Lithium Chloride