Spindler K P, Imro A K, Mayes C E, Davidson J M
Department of Orthopaedics and Rehabilitation, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
J Orthop Res. 1996 Jul;14(4):542-6. doi: 10.1002/jor.1100140407.
The healing responses of the anterior cruciate ligament and the patellar tendon differ markedly. The anterior cruciate ligament fails to heal, whereas the patellar tendon heals slowly. The basis of these differences is unknown. Since cellular proliferation is a critical element of healing, we investigated the response to explants of anterior cruciate ligament and patellar tendon from sheep knees to platelet-derived growth factor-AB and transforming growth factor beta 1 as a function of time and dose. Explants cultured for 48, 72, and 96 hours with transforming growth factor beta 1 (0-100 ng/ml) or platelet-derived growth factor-AB (0-200 ng/ml) were radiolabeled for the final 24 hours with [3H]thymidine, and DNA synthesis was quantified as trichloroacetic acid-precipitable radioactivity normalized to dry tissue weight. Statistical analyses (analysis of variance) showed that transforming growth factor beta 1 induced a significant proliferative response in the anterior cruciate ligament at 96 hours with equivalent responses at 10, 50, and 100 ng/ml, whereas the patellar tendon only responded to one condition, 10 ng/ml at 96 hours. Conversely, the patellar tendon had a significant dose-dependent response to platelet-derived growth factor-AB at 72 and 96 hours, whereas the anterior cruciate ligament showed no proliferative response to platelet-derived growth factor-AB. The minimal response of anterior cruciate ligament to platelet-derived growth factor-AB could explain, at least in part, the poor repair capacity of this tissue. The response of the anterior cruciate ligament to transforming growth factor beta suggests that exogenous transforming growth factor beta may promote initial healing. Although growth factors have the potential to modulate soft-tissue repair, tissue responses in tendons and ligaments may vary at different anatomic sites.
前交叉韧带和髌腱的愈合反应存在显著差异。前交叉韧带无法愈合，而髌腱愈合缓慢。这些差异的原因尚不清楚。由于细胞增殖是愈合的关键因素，我们研究了绵羊膝关节前交叉韧带和髌腱外植体对血小板衍生生长因子 -AB 和转化生长因子β1 的反应，该反应是时间和剂量的函数。用转化生长因子β1（0 - 100 ng/ml）或血小板衍生生长因子 -AB（0 - 200 ng/ml）培养 48、72 和 96 小时的外植体，在最后 24 小时用[3H]胸腺嘧啶核苷进行放射性标记，DNA 合成通过归一化至干组织重量的三氯乙酸可沉淀放射性进行定量。统计分析（方差分析）表明，转化生长因子β1 在 96 小时时在前交叉韧带中诱导了显著的增殖反应，在 10、50 和 100 ng/ml 时反应相当，而髌腱仅在 96 小时时对 10 ng/ml 这一条件有反应。相反，髌腱在 72 和 96 小时时对血小板衍生生长因子 -AB 有显著的剂量依赖性反应，而前交叉韧带对血小板衍生生长因子 -AB 未显示增殖反应。前交叉韧带对血小板衍生生长因子 -AB 的最小反应至少可以部分解释该组织修复能力差的原因。前交叉韧带对转化生长因子β的反应表明外源性转化生长因子β可能促进初始愈合。尽管生长因子有调节软组织修复的潜力，但肌腱和韧带在不同解剖部位的组织反应可能会有所不同。
