Plasticidade tecidual dos sarcômeros e junção miotendínea de ratos submetidos à imobilização articular e remobilização aquática: análises histoquímica, ultraestrutural e morfométrica
Arquivos
Data
2020-02-19
Autores
Rocha, Lara Caetano [UNESP]
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Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
A atrofia por desuso é caracterizada pela redução e perda de tecido muscular esquelético, é comum da utilização de imobilização articular no tratamento de lesões, e apesar de seus efeitos terapêuticos promove efeitos residuais em importantes mecanismos do aparelho locomotor, como nos sarcômeros em série que compõem o músculo estriado esquelético, e também na junção miotendínea (JMT), principal área anatômica especializada do aparelho locomotor, localizada na interface entre o músculo e o tendão, responsável pela transmissão de força. O treinamento aquático proporciona diversos benefícios ao indivíduo e foi utilizado como método de remobilização aquática para a reabilitação dos efeitos deletérios decorrentes da imobilização. O objetivo do presente estudo consistiu em descrever os efeitos da plasticidade tecidual na JMT do músculo gastrocnêmio de ratos Wistar adultos submetidos a imobilização articular e remobilização aquática por meio da análise de suas características histoquímica, ultraestrutural e morfométrica. Foram utilizados ratos com 90 dias, divididos em 5 grupos: Sedentário (S), Imobilizado (I), Treinado (T), Imobilizado Livre (IL) e Imobilizado Treinado (IT). Os grupos I, IL e IT foram submetidos a imobilização articular e os grupos T e IT ao protocolo de treinamento em meio aquático. A análise dos aspectos estruturais do ventre e JMT ocorreram através da técnica de microscopia de luz corada com Hematoxilina-Eosina e Picro-sírus, através da análise histoquímica de ATPase Miofibrilar foram identificados e mensurados a área de secção transversa (AST) e análise esteriológica da Densidade/Volume dos diferentes tipos miofibrilares, foram realizadas analises morfoquantivas das características ultraestruturais dos sarcômeros e JMT através da microscopia eletrônica de transmissão, e foram analisados a organização núclear da JMT através de Imunofluorescência. Observamos no grupo I alterações morfoquantitavas de atrofia muscular na organização da JMT, redução da AST e redução da área de contato. No grupo IL observamos lento reestabelecimento de organização dos componentes da região da JMT, com retorno da AST e aspectos dos componentes ultraestruturais da JMT com possível pré-disposição a lesões. Enquanto, no grupo IT observamos grande atividade celular na região miotendínea, aumento da AST, e extensa melhora dos componentes ultraestruturais das JMT que promoveram maior área de contato entre os tecidos muscular e tendíneo. Concluímos que a imobilização articular acarretou atrofia muscular por desuso, o período de remobilização livre decorreu em reestabelecimento em alguns parâmetros, enquanto a remobilização aquática demonstrou eficiente reabilitação dos efeitos deletérios da atrofia muscular para todo tecido muscular.
Muscle atrophy by disuse is characterized for reduction and loss of skeletal muscle tissue, it is common in the use of joint immobilization in the treatment of injuries, and despite it is therapeutic effects promotes residual effects on important mechanisms of the locomotor system, as in the sarcomeres in series that compose the striated skeletal muscle, and also at the myotendinous junction (MTJ), the main specialized anatomical area of the locomotor apparatus, located at the interface between the muscle and tendon, responsible for force transmission. Water training provides several benefits for individual and was used as na aquatic remobilization method to rehabilitate the deleterious effects of immobilization. The present study aimed to describe the effects of tissue plasticity in MTJ on the gastrocnemius muscle of adult Wistar rats submitted to joint immobilization and aquatic remobilization by analyzing their histochemical, ultrastructural and morphometric characteristics. Rats with 90 days old were divided into 5 groups: Sedentary (S), Immobilized (I), Trained (T), Immobilized/Free (IL) and Immobilized/Trained (IT). The I, IL and IT groups underwent to joint immobilization and T and IT for aquatic training protocol. The analysis of structural aspects of the belly and myotendinous junction occurred through the technique of light microscopy stained with Hematoxylin-Eosin and Picrosirus, through the histochemical analysis of the myofibrillar ATPase were we identified the different myofibrillary types and realized the morphometric analysis of cross-section área (CSA) and Density/Volume, the morphometrical analyzes of the sarcomeres and ultrastructural characteristics of MTJ were performed by transmission electron microscopy, and the nuclear organization of MTJ were analyzed by immunofluorescence. We observed in I group morphometrical changes of muscular atrophy in reduction of CSA, organization of the MTJ and reduction of the contact area. In the IL group, we present slow re-establishment of structural components organization of the MTJ region, with the return of CSA and aspects of the ultrastructural components of the MTJ with a possible predisposition to injuries. While, in the IT group we observed great cellular activity in the myotendinous region, CSA increased, and extensive improvement of MTJ ultrastructural componentes that promoted greater contact area between the muscle and tendon tissues. We conclude that joint immobilization resulted in muscle atrophy by disuse, the free remobilization period was reestablished in some parameters, while aquatic remobilization demonstrated efficient rehabilitation of the deleterious effects of muscle atrophy for all muscle tissue.
Muscle atrophy by disuse is characterized for reduction and loss of skeletal muscle tissue, it is common in the use of joint immobilization in the treatment of injuries, and despite it is therapeutic effects promotes residual effects on important mechanisms of the locomotor system, as in the sarcomeres in series that compose the striated skeletal muscle, and also at the myotendinous junction (MTJ), the main specialized anatomical area of the locomotor apparatus, located at the interface between the muscle and tendon, responsible for force transmission. Water training provides several benefits for individual and was used as na aquatic remobilization method to rehabilitate the deleterious effects of immobilization. The present study aimed to describe the effects of tissue plasticity in MTJ on the gastrocnemius muscle of adult Wistar rats submitted to joint immobilization and aquatic remobilization by analyzing their histochemical, ultrastructural and morphometric characteristics. Rats with 90 days old were divided into 5 groups: Sedentary (S), Immobilized (I), Trained (T), Immobilized/Free (IL) and Immobilized/Trained (IT). The I, IL and IT groups underwent to joint immobilization and T and IT for aquatic training protocol. The analysis of structural aspects of the belly and myotendinous junction occurred through the technique of light microscopy stained with Hematoxylin-Eosin and Picrosirus, through the histochemical analysis of the myofibrillar ATPase were we identified the different myofibrillary types and realized the morphometric analysis of cross-section área (CSA) and Density/Volume, the morphometrical analyzes of the sarcomeres and ultrastructural characteristics of MTJ were performed by transmission electron microscopy, and the nuclear organization of MTJ were analyzed by immunofluorescence. We observed in I group morphometrical changes of muscular atrophy in reduction of CSA, organization of the MTJ and reduction of the contact area. In the IL group, we present slow re-establishment of structural components organization of the MTJ region, with the return of CSA and aspects of the ultrastructural components of the MTJ with a possible predisposition to injuries. While, in the IT group we observed great cellular activity in the myotendinous region, CSA increased, and extensive improvement of MTJ ultrastructural componentes that promoted greater contact area between the muscle and tendon tissues. We conclude that joint immobilization resulted in muscle atrophy by disuse, the free remobilization period was reestablished in some parameters, while aquatic remobilization demonstrated efficient rehabilitation of the deleterious effects of muscle atrophy for all muscle tissue.
Descrição
Palavras-chave
Junção miotendínea, Sarcômero, Núcleo, Atrofia muscular, Remobilização aquática, Myotendinous junction, Sarcomere, Nucleus, Muscle atrophy, Aquatic remobilization