De Mello Malheiro Olga Cristina, Giacomini Camila Tateishi, Justulin Luis Antonio, Delella Flávia Karina, Dal-Pai-Silva Maeli, Felisbino Sérgio Luis
São Paulo State University (UNESP), School of Science and Technology, Department of Physical Education, Presidente Prudente, SP, Brazil.
Anat Rec (Hoboken). 2009 Oct;292(10):1656-62. doi: 10.1002/ar.20953.
Increased activity of matrix metalloproteinases (MMPs) -2 and -9 was found in calcaneal tendon after physical training. However, little attention has been given to the distinct biomechanical and tissue structure of the calcaneal tendon's proximal and distal regions. Herein, we evaluated the effect of two types of physical activities on tendon morphology and matrix metalloproteinase activities in the proximal and distal regions of rat calcaneal tendon, separately. Adult male Wistar rats from control, water-adapted, vertical-jumping, and treadmill-running groups were sacrificed after 1 or 4 days of physical exercise, 6 hr after the end of that day's exercise session. Tendons were processed for histology, morphometry, and gelatin zymography. Tendons from adapted and trained animals showed active secretory cells and increased thickness, cellularity, and blood vessel volume fraction of peritendinous sheath, but without inflammatory process. In the proximal region, both pro- and active MMP-2 were increased after vertical jumping, but only pro-MMP-2 was increased after treadmill running. In contrast, in the distal region, both exercise types increased the activity of pro- and active MMP-2, especially treadmill running, which increased the active MMP-2 by about 11- and eightfold, respectively, after 1 and 4 days of training. No activity of MMP-9 was observed in either tendon region in this study. In conclusion, distal and proximal regions of calcaneal tendon exhibit differential intensities of tissue remodeling after treadmill running or vertical jumping and MMP-2, in the absence of inflammation, plays a major role in this adaptive response.
在体育训练后，发现跟腱中基质金属蛋白酶（MMPs）-2和-9的活性增加。然而，跟腱近端和远端区域独特的生物力学和组织结构却很少受到关注。在此，我们分别评估了两种体育活动对大鼠跟腱近端和远端区域肌腱形态和基质金属蛋白酶活性的影响。成年雄性Wistar大鼠分为对照组、水适应组、垂直跳跃组和跑步机跑步组，在体育锻炼1天或4天后，于当天锻炼结束后6小时处死。对肌腱进行组织学、形态测量和明胶酶谱分析。适应和训练动物的肌腱显示出活跃的分泌细胞，并且腱周鞘的厚度、细胞密度和血管体积分数增加，但无炎症过程。在近端区域，垂直跳跃后前MMP-2和活性MMP-2均增加，但跑步机跑步后仅前MMP-2增加。相反，在远端区域，两种运动类型均增加了前MMP-2和活性MMP-2的活性，尤其是跑步机跑步，在训练1天和第4天后，活性MMP-2分别增加了约11倍和8倍。在本研究中，在任一肌腱区域均未观察到MMP-9的活性。总之，在没有炎症的情况下，跑步机跑步或垂直跳跃后跟腱的远端和近端区域表现出不同强度的组织重塑，并且MMP-2在这种适应性反应中起主要作用。
