Influência dos exercícios físicos de baixa e alta intensidade sobre o limiar de hipernocicepção e outros parâmetros em ratos

Abstract

Physical exercise practice is an important habit to maintain the physical and emotional well-being of those who regularly adopt it, and can bring great benefits to health. However, depending on the type, intensity, frequency and duration of the exercises, they can also do a certain degree of harm to the organism. As a benefit, the role of physical exercise is described in the specific and non-specific immune function and, in the latter, the inflammatory process stands out. Therefore, the purpose of this study was to show the effects of low and high intensity physical exercises on hypernociception, and to evaluate the body mass and the relative weight of some organs in rats. For the study, male adult Wistar rats were used and submitted (trained group) or not submitted (non-trained group) to physical exercises on an ergometric treadmill. The acute inflammation was induced by an injection of carrageenin-0.5% into the plantar tissue of the left hind paw of each rat and the nociception was measured by the plantar test before and after 1, 2, 3, 4, 6, 8 and 24 hours. At the end of the evaluations, the rats were submitted to deep anesthesia until their euthanasia, to collect and weigh the adrenal glands, heart, spleen and kidneys, and to subsequent histopathological study of those tissues. The statistical analysis of the results showed a significant increase (P < 0.05) of the hypernoniception threshold in H 2 , H 3 , H 4 and H 6 moments in animals trained at high intensity. There was also a significant reduction (P < 0.05) in body mass besides hypertrophy of the adrenal glands and heart and an increase in the kidneys relative weight of the rats trained at high intensity, in addition to adrenal hypertrophy of the animals trained at low intensity. There were no statistically significant changes in the other parameters evaluated in this study. We concluded that physical exercises on a treadmill were capable of changing the nociception, body mass and the relative weight of some organs, but in a way that was dependent on the exercises protocol applied to the animals.

Effect of low-level LASER and neural mobilization on nociceptive threshold in experimental sciatica

“…Pain induced by tissue injury is considered a body protection mechanism which may be triggered by different stimuli which depolarize pain receptors (nociceptors), and pain perception and body response to painful stimuli are called nociception 1 . Peripheral nerves are constant targets for crush, compression and transection injuries.…”

Efeito do exercício físico contínuo e intervalado no peso e perfil bioquímico de ratas Wistar prenhes e consequências no peso da prole

“…However, a consensus has not been reached in the literature about the correlation between gestational weight gain and physical exercises practice (14,15) , but some studies have mentioned reduction in weight gain (16,17) . Lana et al (18) studied the effects of forced exercise in rats and observed that there was not statistically significant difference between the animals trained in low intensity and the untrained ones; however, lower final body weight was detected in the animals from the group with high intensity compared with the ones from the untrained group.…”

Efeitos dos exercícios físicos sobre o edema inflamatório agudo em ratos Wistar

“…Sobre este aspecto, vários estudos realizados em seres humanos e ratos, reforçam o conceito de que os exercícios físicos, em suas diversas modalidades, são capazes de alterar várias funções do organismo, como aquelas relacionadas ao sistema neuroendócrino. Neste sentido, Lana et al (6) relataram diminuição do limiar de hipernocicepção, de origem inflamatória, em ratos treinados em alta intensidade em esteira ergometria, provavelmente por alterações no sistema neuroendócrino, entre outros fatores. Todavia, os estudos publicados até o momento mostram grandes discrepâncias de resultados, por várias razões, como a utilização de diferentes protocolos de treinamento físico (forçado ou voluntário), a variação no tipo, duração, freqüência e intensidade destes exercícios, bem como a multiplicidade de testes utilizados para avaliação da influência dos exercícios físicos nos parâmetros investigados (33) .…”

“…Resultados de Gonçalves e Luciano (5) com ratos treinados por meio de sessões diárias de natação mostraram redução de eosinófilos circulantes e de monócitos no local inflamado, sugerindo uma atenuação da resposta inflamatória, quando comparados com ratos sedentários. Ainda, nesta direção, Lana et al (6) também evidenciaram redução da hipernocicepção durante a resposta inflamatória aguda induzida experimentalmente em ratos treinados em esteira ergométrica, sob um protocolo de alta intensidade, utilizando-se cerca de 70% do consumo máximo de oxigênio (VO 2 máximo) destes animais.…”