High and low responders to novelty and mesolimbic noradrenaline: effects of noradrenergic agents on radial-maze performance.
The authors used high and low responders to novelty (HRs and LRs, respectively) to examine the effects of noradrenergic injections into the nucleus accumbens using a special radial-maze task. During the 5 successive test days, solvent-treated HRs acquired this task faster than LRs. Isoproterenol (beta-agonist) combined with phenylephrine (alpha-agonist) improved acquisition in LRs but not in HRs; this effect was counteracted by propranolol (beta-antagonist) and phentolamine (alpha-antagonist). Propranolol combined with phentolamine, as well as phentolamine alone, disrupted acquisition in HRs but not in LRs. Data show that the effects of noradrenergic agents in HRs and LRs are due to differences in acquisition directed by type-specific differences in functional mesolimbic noradrenaline.
Tuinstra
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Department of Psychoneuropharmacology, University of Nijmegen, The Netherlands.
Cobelens
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Lubbers
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Verheij
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Cools
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D000316:Adrenergic alpha-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D005106:Exploratory Behavior / Q000187:drug effects / Q000502:physiology*; D007545:Isoproterenol / Q000008:administration & dosage / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects / Q000502:physiology*; D009638:Norepinephrine / Q000008:administration & dosage / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D010656:Phenylephrine / Q000008:administration & dosage / Q000494:pharmacology*; D011433:Propranolol / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats
D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D010656:Phenylephrine; D011433:Propranolol; D007545:Isoproterenol; D009638:Norepinephrine