Complete stress shielding of the Achilles tendon: ultrastructure and level of interleukin-1 and TGF-β.
Few studies emphasize the collagen metabolism-related cytokines and ultrastructure of the completely stress-shielded Achilles tendon. In this study, we used a rat model with complete stress shielding of the Achilles tendon to observe the changes in the ultrastructure of the Achilles tendon and concentration of IL-1 and TGF-β 3 weeks after stress shielding. The model group comprised 12 male Sprague-Dawley rats. The stress of the Achilles tendon of the left hind limb was shielded through tendon cerclage combined with sciatic nerve transection, and the right served as a normal control. Three weeks later, the ultrastructure of the Achilles tendon was observed under electron microscopy and IL-1 and TGF-β levels were determined by enzyme-linked immunosorbent assay. Compared with the control side, collagen fibrils of the shielded Achilles tendons were irregularly arranged and loose. The number of small-diameter collagen fibrils increased significantly with the decrease of the average diameter of collagen fibrils. At the same time, IL-1 concentrations increased significantly in the model group as compared to that in the control group, but no significant difference was found in TGF-β levels. These results suggest that IL-1 may play an important role in the change of ultrastructure after stress shielding.
Department of Rehabilitation Medicine, Affiliated Sixth People’s Hospital of Shanghai Jiaotong University, Shanghai, China.
Wei
W
Wang
Xiaoyu
X
Tang
Jing
J
Zhang
Xiaoyan
X
Yan
Yanhong
Y
Ma
D000125:Achilles Tendon / Q000378:metabolism / Q000601:surgery* / Q000648:ultrastructure; D000818:Animals; D003094:Collagen / Q000378:metabolism / Q000648:ultrastructure; D003286:Contracture / Q000517:prevention & control; D004195:Disease Models, Animal; D005593:Fracture Fixation, Internal; D006614:Hindlimb; D007375:Interleukin-1 / Q000378:metabolism*; D008297:Male; D046529:Microscopy, Electron, Transmission; D051381:Rats; D017207:Rats, Sprague-Dawley; D012584:Sciatic Nerve / Q000601:surgery; D013314:Stress, Mechanical; D013536:Suture Techniques / Q000295:instrumentation; D013537:Sutures; D013718:Tensile Strength; D016212:Transforming Growth Factor beta / Q000378:metabolism*
D007375:Interleukin-1; D016212:Transforming Growth Factor beta; D003094:Collagen