title: Is the unilateral lesion of the left substantia nigra pars compacta sufficient to induce working memory impairment in rats?
abstract: Adult male Wistar rats with a substantia nigra pars compacta (SNc) lesion induced by intranigral administration of 1 micromol 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were used as a model of early phase Parkinson's disease (PD). This lesion caused a partial depletion of striatal dopamine (DA). The animals were submitted to a spatial working memory version of the water maze task in which they had to find a hidden (submersed) platform using online-maintained information that the platform remains in the same place during four consecutive trials, but that it is moved to another place every training day. Left, but not right SNc-lesioned rats were impaired in finding the platform in the second trial. This result suggests that the left SNc plays a key role in spatial working memory. Control experiments ruled out the possibility that motor impairment, sensory neglect, and/or impairment in the mental representation of the contralateral spatial environment had affected performance of the SNc-lesioned rats.
authors.affiliation: Laboratório de Fisiologia e Farmacologia do Sistema Nervoso Central, Departamento de Farmacologia, Departamento de Biquimica e Biologia Molecular, Departamento de Quimica, UFPR, C.P. 19.031, 81531-980 Curitiba PR, Brazil.
authors.forename: Maria Ines
authors.initials: MI
authors.lastname: Bellissimo
authors.forename: Ivana
authors.initials: I
authors.lastname: Kouzmine
authors.forename: Marcelo Machado
authors.initials: MM
authors.lastname: Ferro
authors.forename: Brás Heleno
authors.initials: BH
authors.lastname: de Oliveira
authors.forename: Newton Sabino
authors.initials: NS
authors.lastname: Canteras
authors.forename: Claudio
authors.initials: C
authors.lastname: Da Cunha
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D004193:Discrimination Learning / Q000502:physiology; D004195:Disease Models, Animal; D004292:Dominance, Cerebral / Q000502:physiology*; D004924:Escape Reaction / Q000502:physiology; D020267:MPTP Poisoning / Q000503:physiopathology; D008297:Male; D018782:Maze Learning / Q000502:physiology*; D008570:Memory, Short-Term / Q000502:physiology*; D010300:Parkinson Disease / Q000503:physiopathology*; D051381:Rats; D017208:Rats, Wistar; D013037:Spatial Behavior / Q000502:physiology*; D013378:Substantia Nigra / Q000187:drug effects / Q000502:physiology*; D013550:Swimming / Q000502:physiology