Expressão de proteínas sinápticas e estruturais no sistema nervoso de ratos submetidos a diferentes modalidades de exercício físico

• Autor(a) principal: Garcia, Priscila Crespo
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório do Centro Universitário Braz Cubas
• Texto Completo: https://repositorio.cruzeirodosul.edu.br/handle/123456789/1143
• topic: Exercício físico; Proteínas estruturais; Proteínas sinápticas; Exercício acrobático; Exercício em esteira; Circuitos neurais motores; FISIOTERAPIA E TERAPIA OCUPACIONAL

Aim: Several types of physical exercise with different protocols are able to promote plastic changes in the nervous system. The relationship of these plastic responses to structural and synaptic proteins in motor regions of the brain are less understood. The aim of this study was to evaluate the expression of the proteins synapsin I (SYS), synaptophysin (SYP), microtubule-associated proteins 2 (MAP2) and neurofilaments (NF) in the motor cortex, striatum and cerebellum of adult rats subjected to moderate intensity treadmill exercise (EE) and acrobatic exercise (AC). In addition, we analyzed the motor behavior and balance of rats of the different groups. Methods and results: Adult male Wistar rats, were separated into 3 groups: control-sedentary (n=15), EE (n=20) and AC (n=20). EE rats trained on a treadmill with a top speed of 0.6km/h for 40 minutes, 3 times a week for 4 weeks. In the AC group, the rats covered 5 times a circuit which was composed by several obstacles, three times a week for 4 weeks. For behavioral analyses we used the “Rotarod” system. In addition, in the AC group we analyzed the performance of the rats, by recording the time of passage through the acrobatic circuit. The expression of proteins in the motor cortex, striatum and cerebellum was analysed by immunohistochemical and immunoblotting techniques, and the data subjected to statistical analysis using one-way ANOVA with Tukey post hoc test when appropriate. The significance level used was 5%. Behavioral analysis showed a significant increase in time spent on the rotarod only in groups EE and AC, from the second week of training through the end of 4 weeks. As of the motor performance, acrobatic animals showed a statistically significant reduction of time needed to traverse the circuit, from 2 – 4 weeks of training. Our results also showed that rats from the AE group showed a significant increase of MAP2 and SYP in the motor cortex, of all four proteins in the striatum and of SYS in the cerebellum. On the other hand, the rats from the TE group exhibited a significant increase of SYS and SYP in the motor cortex, of NF68, SYS and SYP in the striatum, and of MAP2, NF and SYS in the cerebellum, whereas NF was decreased in the motor cortex and molecular layer of the cerebellar cortex. Thus, the main changes in the AC group were seen in areas involved in basal nuclei-thalamic-cortical circuits, whereas in group EE the main changes were seen in the regions involved in cerebellar-thalamic-cortical circuits. Conclusion: Our data suggest that exercise on a treadmill and acrobatic exercise differentially modulate synaptic and structural proteins in different brain areas, playing an important role in exercise-dependent plasticity in motor regions of the brain.