D1 and D2 receptor antagonist injections in the prefrontal cortex selectively impair spatial learning in mice

Neuropsychopharmacology. 2007 Feb;32(2):309-19. doi: 10.1038/sj.npp.1301176. Epub 2006 Aug 9.

Abstract

The prefrontal cortex (PFC) is a cortical area involved in selecting and retaining information to produce complex behaviors. Within the PFC, the dopaminergic system plays an important role in information processing. Thus, the objective of this study was to test whether bilateral administration of the D1 and D2 receptor antagonists in the prelimbic region of the PFC influenced the performance of mice in a non-associative spatial learning task. CD1 mice were bilaterally microinjected in the PFC with either the D1 receptor antagonist, SCH23390 (SCH 6.25; 12.5; 50 ng), or the D2 receptor antagonist, sulpiride (SULP 12.5; 50; 100 ng) and placed into an open field containing five different objects. After three sessions of habituation two objects were repositioned (spatial change) and in the subsequent session one of the objects was substituted (non-spatial change). No significant alteration was observed in the habituation pattern of the animals after D1 or D2 receptor blockade. When two of the objects were displaced, control mice explored the displaced objects far more than the non-displaced ones, while mice treated with SCH or SULP spent a comparable amount of time re-exploring the two object categories. Conversely, DA antagonists had no effects on the discrimination of the new object. Thus, the administration of both SCH and SULP selectively impaired the ability of mice to discriminate a spatial change, without affecting any other behavioral parameter. These findings could provide a model to study the role of the PFC dopaminergic system in spatial learning and to study the neural mechanisms underlying cognitive and attention deficits often observed in psychiatric disorders.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Afferent Pathways / drug effects
  • Afferent Pathways / metabolism
  • Afferent Pathways / physiopathology
  • Animals
  • Benzazepines / pharmacology
  • Disease Models, Animal
  • Dopamine / metabolism
  • Dopamine Antagonists / pharmacology*
  • Dopamine D2 Receptor Antagonists
  • Drug Administration Routes
  • Habituation, Psychophysiologic / drug effects
  • Habituation, Psychophysiologic / physiology
  • Learning / drug effects
  • Learning / physiology
  • Learning Disabilities / chemically induced
  • Learning Disabilities / metabolism*
  • Learning Disabilities / physiopathology
  • Male
  • Memory Disorders / chemically induced
  • Memory Disorders / metabolism*
  • Memory Disorders / physiopathology
  • Mice
  • Motor Activity / drug effects
  • Motor Activity / physiology
  • Neuropsychological Tests
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / metabolism*
  • Prefrontal Cortex / physiopathology
  • Receptors, Dopamine D1 / antagonists & inhibitors
  • Receptors, Dopamine D1 / metabolism*
  • Receptors, Dopamine D2 / metabolism*
  • Space Perception / drug effects
  • Space Perception / physiology
  • Sulpiride / pharmacology
  • Ventral Tegmental Area / drug effects
  • Ventral Tegmental Area / metabolism
  • Ventral Tegmental Area / physiopathology

Substances

  • Benzazepines
  • Dopamine Antagonists
  • Dopamine D2 Receptor Antagonists
  • Receptors, Dopamine D1
  • Receptors, Dopamine D2
  • Sulpiride
  • Dopamine