Efeitos da corrida em esteira em músculos sóleos de ratos encurtados por imobilização

Abstract

O objetivo deste trabalho foi verificar as adaptações de peso e comprimento do músculo sóleo de ratos Wistar machos, além da estimativa do total de sarcômeros em série e comprimento médio dos sarcômeros, quando submetidos a um processo de remobilização em esteira. Foram utilizados 18 ratos (Wistar), divididos em três grupos: GC -músculo sóleo esquerdo (MSE) imobilizado e remobilizado solto; G10 -MSE imobilizado e remobilizado em velocidade de 10m/min; e G12 (n = 6) -MSE imobilizado e remobilizado em velocidade de 12m/min. Os resultados mostraram as seguintes variações, peso muscular: GC -22,35% (p = 0,0089), G10 -12,52% (p = 0,0623), G12 -12,07%, (p = 0,0004); comprimento muscular: GC -5,47% (p = 0,0120), G10 -3,31% (p = 0,2868), G12 0,41% (p = 0,8987); estimativa de sarcômeros em série: GC -15,42% (p = 0,0047), G10 -10,87% (p = 0,0193), G12 -4,97 (p = 0,2409); comprimento de sarcômeros GC 11,16% (p = 0,0142), G10 9,31% (p = 0,1270), G12 5,58% (p = 0,1327). Conclui-se que G12 obteve maior eficácia após o período de imobilização, pois apresentou maior semelhança com o membro não imobilizado.Palavras-chave: reabilitação, músculo esquelético, sarcômeros. ABSTRACTThe aim of this work was to compare weight and length adaptations of the soleus muscle of male Wistar rats as well as estimation of the total number of serial sarcomere and mean sarcomere length, when they are submitted to remobilization on treadmill. 18 Wistar male rats were used and divided in the three following groups: CG -left soleus (LS) muscle immobilized and remobilized free in the cage; G10 -LS muscle immobilized and remobilized in speed of 10 m/min on treadmill; and G12 -LS muscle immobilized and remobilized in speed of 12 m/min. The right muscles (RS) of each animal were used for comparison. The results showed the following variations, muscular weigh: CG -22.35% (p = 0.0089), G10 -12.52% (p = 0.0623), G12 -12.07%, (p = 0.0004); muscle length: CG -5.47% (p = 0.0120), G10 -3.31% (p = 0.2868), G12 0.41% (p = 0.8987); estimation of number of serial sarcomere: CG -15.42% (p = 0.0047), G10 -10.87% (p = 0.0193), G12 -4.97 (p = 0.2409); sarcomere length: CG 11.16%, (p = 0.0142), G10 9.31% (p = 0.1270), G12 5.58% (p = 0.1327). It was concluded that G12 presented the best effectiveness after immobilization period since it presented greater similarity with the non-immobilized soleus.Keywords: rehabilitation, skeletal muscle, sarcomere. INTRODUÇÃOA literatura científica comprova que os músculos esqueléticos possuem plasticidade muscular, ou seja, respondem a diferentes estímulos impostos, dentre eles: exercícios físicos, alterações hormonais, nutrição, denervação, eletroestimulação, imobilização, dentre outros (1)(2)(3)(4) . A inatividade causa ao músculo significativo remodelamento, incluindo a perda de proteínas miofibrilares, mudanças em atividades metabólicas, alterações vasculares e neurais (5) . Contudo, a imobilização, que gera desuso, ainda é uma opção de tratamento freqüentemente usada em distúrbios musculoesqueléticos, apesar da ocorrência da atro...

Avaliação de parâmetros histomorfométricos em sóleos de ratos submetidos à remobilização por salto em meio aquático

“…Those findings comply with previous studies that used the same model and presented reduction of sarcomeres along the muscle when animals were submitted to remobilization by swimming, low intensity walk on treadmill or series of static stretch [19][20][21] . Butterfield and Herzog 30 highlighted that tension in the muscle-tendon unit is not the primary source of sarcomerogenesis but it may occur in some cases of eccentric exercise 28 like contractions and disregarded in the present study.…”

“…Tonic muscles like soleus present a greater hypotrophy. That is the reason why devising resources to help people have their optimal movements back is extremely important besides the existing electrical stimulation and physical exercises [17][18][19][20][21][22] . Physical exercise is beneficial to muscle recovery as stated by Malysz et al 23 in his study on muscle recovery of Table 2.…”

Efeitos do ultrassom terapêutico associados ao alongamento estático sobre parâmetros histomorfométricos longitudinais de sóleos imobilizados de ratos

“…A short immobilization period (seven days) is already enough for the muscle to suffer morphometric and mechanical adaptations, such as reduction of muscular mass and length, number of sarcomeres, increase of the conjunctive tissue density and reduction of the maximum resistance of muscular rupture [2][3][4] . Increase of conjunctive tissue induces to abnormal crossed ligations of conjunctive tissue fibers, which results in fast muscular stiffness and reduction of range of motion 1,5 .…”

Mechanical Properties of Achilles Tendon in Rats Induced to Experimental Diabetes

“…This makes it possible for the gesture of locomotion, which would be mechanically unfavorable for muscle alone, to be performed using less energy. 7,15,27 Several studies have evaluated the mechanical properties of tendons and documented their plasticity in response to different situations, such as immobilization and/or suspension, 3,22 vibration strength training, 16 tensile strength, 32 training strength, 19,28,29 and endurance training. 11,16,29,32 In the specific case of diabetes, there are few studies on the mechanical properties of tendons.…”