Jafari Leila, Vachon Pascal, Beaudry Francis, Langelier Eve
Département de génie mécanique, Université de Sherbrooke, Sherbrooke, Québec, Canada.
Département de Biomédecine Vétérinaire, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec, Canada.
Physiol Rep. 2015 Jan 19;3(1). doi: 10.14814/phy2.12265. Print 2015 Jan 1.
Animal models of forced running are used to study overuse tendinopathy, a common health problem for which clear evidence for effective and accessible treatments is still lacking. In these models, pain evaluation is necessary to better understand the disease, help design and evaluate therapies, and ensure humane treatment of the animals. Therefore, the main objective of this study was to evaluate pain and pathologic findings in an animal model of moderate Achilles tendinopathy induced by treadmill running. Air puffs, instead of electrical shocks, were used to stimulate running so that pain associated with stimulation would be avoided. Pressure pain sensitivity was evaluated in vivo using a new instrumented plier, whereas spinal cord peptides were analyzed ex vivo with high-performance liquid chromatography tandem mass spectrometry. Tendon histologic slides were semiquantitatively evaluated, using the Bonar score technique and biomechanical properties, using the traction test. After 8 weeks of treadmill running (2 weeks for adaptation and 6 weeks for the lesion protocol), the protocol was stopped because the air puffs became ineffective to stimulate running. We, nevertheless, observed some histologic changes characteristic of overuse tendinopathy as well as decreased mechanical properties, increased Substance P and dynorphin A peptides but without pressure pain sensitivity. These results suggest that air-puffs stimulation is sufficient to induce an early stage tendinopathy to study new therapeutic drugs without inducing unnecessary pain. They also indicate that pain-associated peptides could be related with movement evoked pain and with the sharp breakdown of the running performance.
强迫跑步动物模型用于研究过度使用性肌腱病，这是一个常见的健康问题，目前仍缺乏有效且可及治疗方法的明确证据。在这些模型中，疼痛评估对于更好地理解疾病、帮助设计和评估治疗方法以及确保对动物的人道对待是必要的。因此，本研究的主要目的是评估由跑步机跑步诱导的中度跟腱肌腱病动物模型中的疼痛和病理发现。使用气吹而非电击来刺激跑步，以便避免与刺激相关的疼痛。使用一种新型带仪器的钳子在体内评估压力疼痛敏感性，而使用高效液相色谱串联质谱法在体外分析脊髓肽。使用博纳尔评分技术对肌腱组织学切片进行半定量评估，并使用拉伸试验评估生物力学特性。在跑步机跑步8周后（2周适应期和6周损伤方案期），由于气吹刺激跑步无效，该方案停止。然而，我们观察到了一些过度使用性肌腱病的特征性组织学变化以及力学性能下降、P物质和强啡肽A肽增加，但没有压力疼痛敏感性。这些结果表明，气吹刺激足以诱导早期肌腱病，以研究新的治疗药物而不引起不必要的疼痛。它们还表明，与疼痛相关的肽可能与运动诱发的疼痛以及跑步性能的急剧下降有关。
