Efeitos do treinamento prévio em natação sobre a carcinogênese experimental do cólon em ratos Wistar

• Autor(a) principal: Freitas, Juliana Silveira de
• Data de Publicação: 2011
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3466
• topic: Exercício; Câncer; Intestino; Exercise; Cancer; Intestine; CNPQ::CIENCIAS DA SAUDE

This study aimed to investigate the effects of prior swimming training prior on the process of experimental colon carcinogenesis induced by 1,2 dimethylhydrazine (DMH) in rats. Wistar rats with 5 weeks of age were randomly divided into 4 groups: control (C) Control + DMH (CD), exercise + DMH (ED), and exercise (E). The animals were housed in collective cages in a room with temperature of 22 ± 2°C and light/dark cycle of 12 hours, where they received food and water ad libitum. Animals from E and ED groups were subjected to a swimming training program (30 min/day, 5 days/week, overload of 6% of body weight) for 8 weeks. In the following two weeks rats from CD and ED groups received two injections of DMH/week, with two days interval between injections. In the following week, after euthanasia the intestine was removed for assessment of aberrant crypt foci (ACF), histomorphometric analysis and counting of inflammatory cells. The liver was removed for determination of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD). The results show that animals of ED group had lower number of ACF in the proximal intestine as compared to CD (6,66 ±2,88 vs 36,66 ±26,53, respectively). No differences between groups were found for the total number of ACF, independent of regions. The number of ACF≤3 was higher than that of ACF>3 in ED (86,33 ±46,71 vs 6,00 ±3,00 respectively) and CD (97,33 ± 43,31 vs 5,33 ± 4,50 respectively) groups. There was no change in antioxidant enzymes in the animals’ liver. No differences between groups were found for crypt length and width. Inflammatory cell count was higher in ED than in CD group (518,20 ±114,44 vs 317,60 ±46,33, respectively). It was concluded that swimming training prior to the induction of colon carcinogenesis in rats reduced the number of FCA in the proximal region and increased the number of inflammatory cells (eosinophils/neutrophils). These findings suggest a protective role of exercise training against the experimental colon carcinogenesis in rats.