Passerieux E, Rossignol R, Letellier T, Delage J P
UFR STAPS, Université Victor Segalen-Bordeaux 2, 12 Avenue Camille Jullian, F-33607 Pessac Cedex, France.
J Struct Biol. 2007 Jul;159(1):19-28. doi: 10.1016/j.jsb.2007.01.022. Epub 2007 Mar 3.
Advances in muscle physiology suggest that the perimysium plays a role in the transmission of lateral contractile forces. This hypothesis is strongly supported by our recent demonstration of the existence of "Perimysial Junctional Plates" in bovine Flexor carpi radialis muscle [Passerieux, E., Rossignol, R., Chopard, A., Carnino, A., Marini, J.F., Letellier, T., Delage, J.P. 2006. Structural organization of the perimysium in bovine skeletal muscle: junctional plates and associated intracellular subdomains. J. Struct. Biol. 154 (2), 206-216] However, the overall organization of the perimysium collagen network, as well as its continuity and heterogeneity, have still not been described in detail throughout the entire muscle. We used an extension of the standard NaOH digestion technique and scanning electron microscopy to analyze perimysium architecture in bovine Flexor carpi radialis muscle. First, we observed that the perimysium is made of a highly ordered network of collagen fibers, binding the myofibers from tendon to tendon. We identified basic collagen cable structures, characterized by a straight portion (3 cm long) in the direction of the myofibers and a curved terminal portion at 60 degrees. These cables reach the myofiber surface at the level of the previously described "Perimysial Junctional Plates". At a higher level of organization, these cables stick together to form the walls of numerous tubes arranged in a overlapping honeycomb pattern around the myofibers. At the ends of these tubes, the straight portions of the collagen cables ramify in large bundles that merge with the tendons. Taken together, these observations identify four levels of organization in the perimysium: (i) Perimysial Junctional Plates that constitute the focal attachment between the perimysium and the myofibers, (ii) collagen plexi attaching adjacent myofibers, (iii) a loose lattice of large interwoven fibers, and (iv) honeycomb tubes connecting two tendons. This spatial arrangement of the perimysium supports the view of a complex pattern of lateral force transmission from myofibers to tendons and adjacent muscles.
肌肉生理学的进展表明，肌束膜在横向收缩力的传递中发挥作用。我们最近在牛的桡侧腕屈肌中证实了“肌束膜连接板”的存在，这一假说得到了有力支持[帕西厄，E.，罗西尼奥尔，R.，肖帕尔，A.，卡尔尼诺，A.，马里尼，J.F.，勒泰利耶，T.，德拉热，J.P. 2006年。牛骨骼肌肌束膜的结构组织：连接板及相关的细胞内亚结构域。《结构生物学杂志》154(2)，206 - 216]。然而，肌束膜胶原网络的整体组织结构，以及其连续性和异质性，在整个肌肉中仍未得到详细描述。我们使用了标准氢氧化钠消化技术的扩展方法和扫描电子显微镜来分析牛桡侧腕屈肌的肌束膜结构。首先，我们观察到肌束膜由高度有序的胶原纤维网络组成，将肌纤维从肌腱连接到肌腱。我们识别出基本的胶原束结构，其特征是在肌纤维方向上有一段直的部分（3厘米长），以及一个呈60度角的弯曲末端部分。这些胶原束在先前描述的“肌束膜连接板”水平到达肌纤维表面。在更高的组织层次上，这些胶原束粘在一起形成许多围绕肌纤维以重叠蜂窝状排列的管的壁。在这些管的末端，胶原束的直的部分分支成大束，与肌腱融合。综上所述，这些观察结果确定了肌束膜的四个组织层次：(i)构成肌束膜与肌纤维之间焦点附着的肌束膜连接板，(ii)连接相邻肌纤维的胶原丛，(iii)大的交织纤维的松散晶格，以及(iv)连接两条肌腱的蜂窝状管。肌束膜的这种空间排列支持了从肌纤维到肌腱和相邻肌肉的复杂横向力传递模式的观点。
