Dopamine signaling in the dorsal striatum is essential for motivated behaviors: lessons from dopamine-deficient mice

Ann N Y Acad Sci. 2008;1129:35-46. doi: 10.1196/annals.1417.003.

Abstract

Genetically engineered mice that lack tyrosine hydroxylase in all dopaminergic neurons become hypoactive and aphagic, and they starve by 4 weeks of age. However, they can be rescued by daily treatment with l-dopa, which restores activity and feeding for about 10 hours. Thus, these mice can be examined in both dopamine-depleted and dopamine-replete states. A series of behavioral experiments lead to the primary conclusion that in the dopamine-depleted state these mice are not motivated to engage in goal-directed behaviors. Nevertheless, they still have a preference for sucrose, they can learn the location of food rewards, and they can form a conditioned-place preference for drugs. Dopamine signaling can be restored to the striatum by several different viral gene-therapy procedures. Restoring dopamine signaling selectively to the dorsal striatum is sufficient to allow feeding, locomotion, and reward-based learning. The rescued mice appear to have normal motivation to engage in all goal-directed behaviors that have been tested. The results suggest that dopamine facilitates the output from dorsal striatum, which provides a permissive signal allowing feeding and other goal-directed behaviors.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Behavior, Animal / physiology*
  • Dopamine / deficiency*
  • Dopamine / metabolism*
  • Feeding Behavior
  • Mice
  • Motivation*
  • Neostriatum / metabolism*
  • Signal Transduction*

Substances

  • Dopamine