Efeito do CGT e do clembuterol no perfil metabólico do músculo esquelético desnervado
Palabras clave:
musculo esqueletico, clembuterol, creatina, glutamina, taurinaResumen
Objetivo
Sabendo-se que três dias após a desnervação a musculatura esquelética apresenta redução na atividade contrátil e na efetividade das vias metabólicas, a proposta deste estudo foi investigar se a suplementação com o complexo creatina/ glutamina/taurina, ou com clembuterol, modifica a intensidade dos eventos deflagrados pós-desnervação, nos músculos sóleo, gastrocnêmio branco e gastrocnêmio vermelho.
Métodos
Ratos machos Wistar foram divididos em 3 grupos (n=6): Desnervado; Desnervado tratado com creatina/glutamina/taurina; e Desnervado tratado com clembuterol, K. M. CANCELLIERO et ai.
diariamente por 3 dias. Avaliariam-se as reservas de glicogênio, o peso do sóleo, a glicemia e a lactatemia.
Resultados
Os músculos desnervados apresentaram redução nas reservas de glicogênio: de 48,0% no músculo sóleo, de 31,0% no gastrocnêmio branco e de 31,0% no gastrocnêmio vermelho. O tratamento com creatina/glutamina/taurina promoveu aumento na:S reservas de glicogênio dos músculos normais (de 9,0% no sóleo, 14,0% no gastrocnêmio branco e 10,0% no gastrocnêmio vermelho) e, de forma mais relevante, nos músculos desnervados (23,0% no sóleo, 25,0% no gastrocnêmio branco e 18,0% no gastrocnêmio vermelho). O clembuterol também promoveu elevação nas reservas de glicogênio, tanto nos músculos normais (15,0% no sóleo, 48,0% no gastrocnêmio branco e 28,0% no gastrocnêmio vermelho), quanto nos desnervados (53,0% no sóleo, 55,0% gastrocnêmio branco e 45,0% no gastrocnêmio vermelho). O peso muscular do sóleo reduziu-se em 3,4% devido à desnervação. Na presença do clembuterol, o peso do músculo sóleo normal aumentou 13,8% e o desnervado somente 4,4%; porém, com o complexo creatina/glutamina/taurina não houve diferença. Quanto às concentrações plasmáticas de glicose e lactato se mantiveram em níveis normais.
Conclusão
As condições energéticas dos músculos esqueléticos suplementados foram melhores dos que os não tratados, destacando o clembuterol, o qual mostrou-se efetivo na manutenção da musculatura sob condição aguda de desnervação.
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