Morphology and expression of genes related to skeletal muscle growth in juveniles of pirarucu

• Published in: Acta scientiarum. Animal sciences 2013-07, Vol.35 (3), p.219-226
• Main Authors: Carani, Fernanda Regina, Duran, Bruno Oliveira Da Silva, De Paula, Tassiana Gutierrez, Piedade, Warlen Pereira, Dal-Pai-Silva, Maeli
• Format: Article
• Language: Spanish
• Subjects: Analysis; Animal morphology; Aquaculture industry; Arapaima gigas; Freshwater; Freshwater fishes; Gene expression; Genes; Growth; Juveniles; Muscles; Myosin; VETERINARY SCIENCES
• ISSN: 1806-2636; 1807-8672; 1807-8672
• DOI: 10.4025/actascianimsci.v35i3.18219

Skeletal muscle growth in the pirarucu (Arapaima gigas) is highly interesting to fish farmers because it provides information about how the mechanism in muscle mass increase, characteristic of the species, is regulated. Pirarucu has specific muscle growth that highlights the species's significance and commercial value. Current research evaluates the morphology and the growth-related gene expression in the red and white skeletal muscles of the pirarucu. Muscle samples were collected from the lateral anterior region and frozen in liquid nitrogen. Histological sections were performed and stained by HE for morphological analysis. Red and white muscle samples were used to determine MyoD, myogenin, and myostatin genes expression by Real-time Polymerase Chain Reaction. Although MyoD and myogenin were not statistically different in the two types of muscles, myostatin was significantly higher in the white rather than in the red muscle. Results show the muscle growth characteristics of the species and may be helpful for improving aquaculture management programs. Keywords: muscle fibre morphology, myogenic regulatory factors, myostatin, skeletal muscle growth, Arapaima gigas, real time PCR. A caracterizacao do crescimento muscular no pirarucu (Arapaima gigas) e de elevado interesse para os piscicultores, pois fornece informacoes de extrema importancia sobre como esse mecanismo e regulado e permite o rapido aumento na massa muscular caracteristico da especie. O pirarucu possui um crescimento muscular tipico, o que destaca sua importancia e seu valor comercial. O objetivo do presente trabalho foi avaliar a morfologia e a expressao de genes relacionados ao crescimento da musculatura esqueletica vermelha e branca do pirarucu. As amostras de musculo vermelho e branco foram obtidas da regiao lateral anterior superficial e profunda, respectivamente, e estas foram congeladas em nitrogenio liquido. Para analise morfologica, cortes histologicos obtidos em criostato foram submetidos a coloracao com HE. A expressao dos genes MyoD, miogenina e miostatina foi feita por PCR em tempo real apos transcricao reversa (RT-qPCR). Em relacao a expressao de MyoD e miogenina, nao houve diferenca estatistica na comparacao entre os musculos; por outro lado, a expressao da miostatina foi significativamente maior no musculo branco, em comparacao com o musculo vermelho. Estes resultados refletem as caracteristicas de crescimento muscular do pirarucu e podem ser uteis na tentativa de melhorar as c