Dopaminergic and cholinergic antagonism in a novel-object detection task with rats.
In a free-choice test, rats display a tendency to interact more with a novel object than a familiar object. In the present report, we assessed the role of the dopaminergic and cholinergic systems in the expression of this novelty detection. Rats were injected with a dopaminergic antagonist (sulpiride, U-99194A, clozapine, or L-745,870) or a cholinergic antagonist (mecamylamine or scopolamine) prior to the free-choice novel-object test. The dopamine antagonists did not block novel-object detection. In contrast, scopolamine, but not mecamylamine, reliably blocked the expression of novelty detection, indicating a role for muscarinic receptors.
Besheer
J
J
Department of Psychology, Burnett Hall, University of Nebraska-Lincoln, Lincoln, NE 68588-0308, USA.
Short
K R
KR
Bevins
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RA
D000818:Animals; D001921:Brain / Q000187:drug effects; D018680:Cholinergic Antagonists / Q000494:pharmacology*; D018492:Dopamine Antagonists / Q000494:pharmacology*; D005106:Exploratory Behavior / Q000187:drug effects*; D005556:Form Perception / Q000187:drug effects*; D008297:Male; D011939:Mental Recall / Q000187:drug effects*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011976:Receptors, Muscarinic / Q000187:drug effects
D018680:Cholinergic Antagonists; D018492:Dopamine Antagonists; D011976:Receptors, Muscarinic