Jacob Carolina Dos Santos, Rocha Lara Caetano, Neto Jurandyr Pimentel, Watanabe Ii-Sei, Ciena Adriano Polican
Department of Physical Education, Laboratory of Morphology and Physical Activity, São Paulo State University "Julio de Mesquita Filho", Rio Claro.
Eur J Histochem. 2019 Aug 6;63(3):3038. doi: 10.4081/ejh.2019.3038.
The aim of this study was to describe the structural and ultrastructural aspects of the myotendinous junction (MTJ) and the proximal and distal sarcomeres of the sternomastoid of aged Wistar rats subjected to an experimental model of menopause and swimming training. A total of 20 female elderly rats were divided into the following four groups (n=5 in each group): sedentary/no-menopausal (SNM), trained/no-menopausal (TNM), sedentary/menopausal (SM), and trained/menopausal (TM). The MTJ samples were dissected and analyzed using transmission electron microscopy. We showed that the TNM Group rats exhibited changes in morphological characteristics as a consequence of physical exercise, which included an increase of 36.60% (P<0.001) in the evagination length of the MTJ and a reduction in the length of the distal (77.38%) (P<0.0001) and proximal (68.15%) (P<0.0001) sarcomeres. The SM Group exhibited a reduction of about 275.93% (P<0.001) in the muscle-tendon interface and in the lengths of distal sarcomeres (55.87%) (P<0.0001) compared with SNM Group. Our results suggest that the swimming training under experimental model of menopause promoted tissue reorganization and increased muscle-tendon interaction with a drastic development in the length and thickness of the sarcoplasmatic invaginations and evaginations. In addition, the sarcomeres exhibited different lengths and a reduction in both groups subjected to swimming training.
本研究旨在描述经历更年期实验模型和游泳训练的老年Wistar大鼠胸锁乳突肌肌腱连接点（MTJ）以及近端和远端肌节的结构和超微结构特征。总共20只雌性老年大鼠被分为以下四组（每组n = 5）：久坐/未绝经组（SNM）、训练/未绝经组（TNM）、久坐/绝经组（SM）和训练/绝经组（TM）。使用透射电子显微镜对MTJ样本进行解剖和分析。我们发现，由于体育锻炼，TNM组大鼠的形态特征发生了变化，其中MTJ的外翻长度增加了36.60%（P<0.001），远端肌节长度减少了77.38%（P<0.0001），近端肌节长度减少了68.15%（P<0.0001）。与SNM组相比，SM组的肌腱界面以及远端肌节长度减少了约275.93%（P<0.001），远端肌节长度减少了55.87%（P<0.0001）。我们的结果表明，在更年期实验模型下进行游泳训练可促进组织重组，并增加肌腱相互作用，同时肌质内陷和外翻的长度和厚度显著增加。此外，两组接受游泳训练的肌节长度不同且均有所缩短。
