Number of muscular fibers by microscopic field: A simple and efficient method to study denervation

• Autor(a) principal: Viterbo, F.
• Data de Publicação: 1989
• Outros Autores: Trindade, J. C.S., Pai, V. D., Curi, P. R.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/219134

An experimental research was performed in dogs to evaluate the changes in gracilis muscle fibers when this muscle is submitted to denervation sectioning its motor nerve. Two experimental groups of six dogs each were used. Animals in Group A were sacrificed 30 ays after denervation of the gracilis muscle, ans animals in Group B were sacrificed 60 days after denervation. The normal gracilis muscle of the opposite leg was used as control. The degree of denervation was evaluated by two parameters: 1) the area of the cross section of the muscular fibers was measured by a planimeter; 2) the number of complete fibers seen in a specific microscopic field. Animals in both groups had atrophy of the muscular fibers, however atrophy was more intense in Group B (60 days) than in Group A (30 days). Conclusion was that the wieght of the denervated muscle is not an accurate method to study the evolution of the degenerating proces although it expresses the muscular atrophy resulting from the denervation. The number of muscular fibers in the microscopic field and the areas of the cross section of the muscular fibers obtained by planimetry are accurate parameters to detect the progress of muscular changes resulting from denervation. considering that it is easier to count the number of muscular fibers in the microscopic field, the authors propose the use of this preferential method in the study of the evolution of muscular changes due to muscle denervation.