title: Differential effects of swimming training on neuronal calcium sensor-1 expression in rat hippocampus/cortex and in object recognition memory tasks.
abstract: Physical activity has been proposed as a behavioral intervention that improves learning and memory; nevertheless, the mechanisms underlying these health benefits are still not well understood. Neuronal Calcium Sensor-1 (NCS-1) is a member of a superfamily of proteins that respond to local Ca(2+) changes shown to have an important role in learning and memory. The aim of the present study was to investigate the effects of swimming training on NCS-1 levels in the rat brain after accessing cognitive performance. Wistar rats were randomly assigned to sedentary (SG) or exercised groups (EG). The EG was subject to forced swimming activity, 30 min/day, 5 days/week, during 8 weeks. Progressive load trials were performed in the first and last week in order to access the efficiency of the training. After the 8 week training protocol, memory performance was evaluated by the novel object preference and object location tasks. NCS-1 levels were measured in the cortex and hippocampus using immunoblotting. The EG performed statistically better for the spatial short-term memory (0.73 ± 0.01) when compared to the SG (0.63 ± 0.02; P<0.05). No statistically significant exercise-effect was observed in the novel object preference task (SG 0.65 ± 0.02 and EG 0.68 ± 0.02; p>0.05). In addition, chronic exercise promoted a significant increase in hippocampal NCS-1 levels (1.8 ± 0.1) when compared to SG (1.17 ± 0.08; P<0,05), but had no effect on cortical NCS-1 levels (SG 1.6 ± 0.1 and EG 1.5 ± 0.1; p>0.05). Results suggest that physical exercise would modulate the state of the neural network regarding its potential for plastic changes: physical exercise could be modulating NCS-1 in an activity dependent manner, for specific neural substrates, thus enhancing the cellular/neuronal capability for plastic changes in these areas; which, in turn, would differentially effect ORM task performance for object recognition and displacement.
authors.affiliation: Núcleo de Neurociências, Departamento de Fisiologia e Biofísica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Luciana Estefani
authors.initials: LE
authors.lastname: Drumond
authors.forename: Flávio Afonso Gonçalves
authors.initials: FA
authors.lastname: Mourão
authors.forename: Hércules Ribeiro
authors.initials: HR
authors.lastname: Leite
authors.forename: Renata Viana
authors.initials: RV
authors.lastname: Abreu
authors.forename: Helton José
authors.initials: HJ
authors.lastname: Reis
authors.forename: Márcio Flávio Dutra
authors.initials: MF
authors.lastname: Moraes
authors.forename: Grace Schenatto
authors.initials: GS
authors.lastname: Pereira
authors.forename: André Ricardo
authors.initials: AR
authors.lastname: Massensini
mesh_terms: D000818:Animals; D002540:Cerebral Cortex / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism*; D015151:Immunoblotting; D008297:Male; D008568:Memory / Q000502:physiology*; D051580:Neuronal Calcium-Sensor Proteins / Q000096:biosynthesis*; D009479:Neuropeptides / Q000096:biosynthesis*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D021641:Recognition, Psychology / Q000502:physiology*; D013550:Swimming
chemical_list: D051580:Neuronal Calcium-Sensor Proteins; D009479:Neuropeptides; C101464:frequenin calcium sensor proteins