Department of Surgery, University of Michigan, Ann Arbor, MI, USA.
Surgery. 2011 Sep;150(3):410-7. doi: 10.1016/j.surg.2011.06.011. Epub 2011 Aug 3.
Laparotomy wound load forces are reduced when dehiscence and incisional hernia formation occur. The purpose of this study was to determine the effects of strain loss on abdominal fascial fibroblast proliferation, orientation, and collagen compaction function.
Cultured rat linea alba fibroblasts were subjected to continuous cyclic strain (CS), CS interrupted at 24 or 48 hours followed by culture at rest (IS-24 and IS-48) or were cultured without mechanical strain (NS). Cell number was measured and images analyzed for cell orientation. Fibroblasts from these groups were seeded onto the surface of (FPCL-S) or mixed into (FPCL-M) a collagen gel matrix and gel area was measured over time.
Continuous strain stimulated proliferation when compared with the nonstrained cells. The loss of strain (IS) delayed proliferation compared with CS throughout (P < .05). CS fibroblasts aligned perpendicular to the direction of strain within 12 hours. Within 12 hours of strain loss, IS-48 fibroblasts became significantly less aligned (P < .0001), and seemed similar to the randomly organized NS fibroblasts 48 hours after strain removal. The CS and IS-24 groups demonstrated faster and greater overall FPCL-M compaction than both the IS-48 and NS groups (P < .0002). The CS group contracted the gel faster than the NS group in FPCL-S (P = .029).
Mechanical strain rapidly induces a proliferative, morphologic, and functional response in abdominal wall fibroblasts that is dependent on the continued presence of the strain signal and quickly lost when the load force is removed. The loss of wound edge tension that occurs during laparotomy wound separation and hernia formation may contribute to impaired wound healing through loss of a key stimulatory mechanical signal with important implications for abdominal wall reconstruction.
当发生裂开和切口疝形成时，剖腹伤口负荷力会降低。本研究的目的是确定应变损失对腹部筋膜成纤维细胞增殖、定向和胶原压缩功能的影响。
培养的大鼠白线成纤维细胞接受连续循环应变（CS），在 24 或 48 小时时中断 CS 后在静止培养（IS-24 和 IS-48）或在没有机械应变的情况下培养（NS）。测量细胞数量并分析细胞定向的图像。将来自这些组的成纤维细胞接种到胶原凝胶基质的表面（FPCL-S）或混合到胶原凝胶基质中（FPCL-M），并随时间测量凝胶面积。
与未受应变的细胞相比，连续应变刺激增殖。与 CS 相比，应变损失（IS）在整个过程中延迟了增殖（P<0.05）。CS 成纤维细胞在 12 小时内垂直于应变方向排列。在应变损失 12 小时内，IS-48 成纤维细胞的定向性明显降低（P<0.0001），并且在去除应变后 48 小时，似乎类似于随机组织的 NS 成纤维细胞。CS 和 IS-24 组显示出比 IS-48 和 NS 组更快和更大的整体 FPCL-M 压实（P<0.0002）。与 NS 组相比，CS 组在 FPCL-S 中更快地收缩凝胶（P=0.029）。
机械应变迅速诱导腹壁成纤维细胞发生增殖、形态和功能反应，该反应依赖于应变信号的持续存在，当负荷力被去除时，该反应迅速丧失。在剖腹伤口分离和疝形成过程中发生的伤口边缘张力损失可能通过丧失重要的机械刺激信号来导致伤口愈合受损，这对腹壁重建具有重要意义。
