title: Deficits in water escape performance and alterations in hippocampal cholinergic mechanisms associated with neonatal monosodium glutamate treatment in mice.
abstract: Mice treated neonatally with monosodium glutamate (MSG) were found to have learning and memory deficits in performing a non-spatial water escape task. Scopolamine impaired the water-escape performance of the control mice but not that of the MSG-treated mice. It was suggested that the water-escape performance deficit in the MSG-treated mice was a result of impaired central cholinergic mechanisms. As such, scopolamine was unable to further incapacitate an already impaired cholinergic system. This is strongly supported by the decreased affinity of the sodium-dependent high-affinity choline uptake observed in the hippocampus. D-Cycloserine, a partial agonist at the glycine site of the NMDA receptor, did not affect the water-escape performance of the MSG-treated and control mice; nor did it alter the effects of scopolamine. This lack of effect of D-Cycloserine may imply that the NMDA receptors are not involved in non-spatial learning, in contrast to their reported involvement in spatial learning.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, National University of Singapore, Kent Ridge, Singapore.
authors.forename: P T
authors.initials: PT
authors.lastname: Wong
authors.forename: L H
authors.initials: LH
authors.lastname: Neo
authors.forename: W L
authors.initials: WL
authors.lastname: Teo
authors.forename: H
authors.initials: H
authors.lastname: Feng
authors.forename: Y D
authors.initials: YD
authors.lastname: Xue
authors.forename: W H
authors.initials: WH
authors.lastname: Loke
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002794:Choline / Q000378:metabolism; D018678:Cholinergic Agents / Q000494:pharmacology*; D003523:Cycloserine / Q000494:pharmacology; D004353:Drug Evaluation, Preclinical; D004924:Escape Reaction / Q000187:drug effects*; D005260:Female; D006624:Hippocampus / Q000187:drug effects*; D008297:Male; D051379:Mice; D011597:Psychomotor Performance / Q000187:drug effects*; D011930:Reaction Time / Q000187:drug effects; D017470:Receptors, Glutamate / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000378:metabolism; D012601:Scopolamine / Q000494:pharmacology; D012970:Sodium Glutamate / Q000494:pharmacology*; D013237:Stereoisomerism
chemical_list: D018678:Cholinergic Agents; D017470:Receptors, Glutamate; D011976:Receptors, Muscarinic; D003523:Cycloserine; D012601:Scopolamine; D002794:Choline; D012970:Sodium Glutamate