Morris water maze learning in Long-Evans rats is differentially affected by blockade of D1-like and D2-like dopamine receptors.
Dopaminergic neurotransmission is involved in several brain functions including spatial cognition. In the present study we examine the effects of systemic administration of D1-like receptor antagonist SCH23390 and D2-like receptor antagonist sulpiride on the acquisition of the Morris water maze task. We used visible versus hidden platform versions of the MWM in order to distinguish between the effects of the drugs on the procedural versus cognitive aspects of the task. SCH23390 was found to prolong escape latencies to the visible platform at a higher dose (0.05mg/kg), whilst the lower dose (0.02mg/kg) left both procedural and cognitive functions almost unchanged. SCH23390 was also found to reduce swimming speed. Sulpiride did not affect the visible platform learning at any of three doses studied (30, 60 and 100mg/kg); the highest dose of sulpiride (100mg/kg) impaired place navigation to the hidden platform, without affecting the swim speed. The results of the present study show a difference in the involvement of D1-like and D2-like receptors in the MWM acquisition.
Stuchlik
Ales
A
Institute of Physiology, Academy of Sciences, Videnska 1083, 14220 Prague, Czech Republic. stuchlik@biomed.cas.cz
Rehakova
Lenka
L
Telensky
Petr
P
Vales
Karel
K
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D065127:Dopamine D2 Receptor Antagonists; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D020332:Rats, Inbred LEC; D017447:Receptors, Dopamine D1 / Q000037:antagonists & inhibitors*
D018492:Dopamine Antagonists; D065127:Dopamine D2 Receptor Antagonists; D017447:Receptors, Dopamine D1