探讨糖尿病对兔膝前交叉韧带重建术后骨隧道的影响

Influence of diabetes on bone tunnel after anterior cruciate ligament reconstruction in rabbits

摘要:

目的：研究糖尿病对兔膝前交叉韧带（anterior cruciate ligament，ACL）重建术的影响，评估模型的有效性。方法：健康雄性新西兰兔36只随机分为A、B 2组。B组于耳缘静脉注射四氧嘧啶（alloxan，ALX） 80 mg/kg，48 h后再予120 mg/kg；A组同法注射等量生理盐水。糖尿病建模后，2组均取自体跟腱重建ACL。通过大体观察、血糖变化、组织学、骨密度（bone mineral den－sity，BMD）、Micro CT、qRT-PCR等评估糖尿病对ACL重建术的影响。结果：大体观察见A组关节腔内移植腱表面光滑、质匀，B组表面毛糙、质脆、色黄。糖尿病造模后至术后8周，B组空腹血糖明显升高且维持稳定，明显高于A组（P<0.01）。组织学发现术后8周时B组胰岛数目及胰岛细胞明显减少（P<0.01）。术后4周，A组骨隧道及周围BMD值明显高于B组（P<0.01）；术后8周，2组BMD值均有升高，组间存在统计学差异（P<0.01）。Micro CT发现，术后4、8周，A组骨隧道截面积分别为（4.544±0.056） mm2、（3.667±0.095） mm2，明显小于B组的（4.734±0.044） mm2、（4.247±0.069） mm2（P<0.05）。结论：应用ALX诱导的糖尿病兔重建膝ACL模型，是一种安全、可靠、经济、稳定的方法；糖尿病兔ACL重建术后骨隧道及周围骨密度减少，骨隧道生长滞后。

Abstract:

Objective：To investigate the influence of diabetes on anterior cruciate ligament（ACL） reconstruction in rabbits and the va－lidity of this animal model. Methods：A total of 36 healthy male New Zealand rabbits were randomly divided into groups A and B. The rabbits in group B were given the injection of alloxan 80 mg/kg via the auricular vein，followed by alloxan 120 mg/kg after 48 hours，and those in group A were given an equal volume of normal saline. After a model of diabetes was established，autologous tendon was used for ACL reconstruction. Gross observation，blood glucose，histology，bone mineral density（BMD），micro-CT，and qRT-PCR were used to observe the influence of diabetes on ACL reconstruction. Results：Gross observation showed that group A had smooth surface and homogeneous texture of the tendon graft in the articular cavity，while group B had rough surface，brittle texture，and yellow color of the tendon graft. From after modeling to 8 weeks after surgery，group B had a significant increase in fasting blood glucose and a significantly higher level of fasting blood glucose than group A（P<0.01）. Histological examination showed that at 8 weeks after surgery，group B had significant reductions in the numbers of pancreatic islets and islet cells（P<0.01）. At 4 weeks after surgery，group A had significantly higher BMD values of the bone tunnel and the surrounding area than group B（P<0.01）；at 8 weeks after surgery，both groups had a significant increase in BMD，and there was a significant difference between the two groups（P<0.01）. Micro-CT showed that compared with group B at 4 and 8 weeks after surgery，group A had a significantly smaller cross-sectional area of the bone tunnel than group B（4.544±0.056） mm2，（3.667±0.095） mm2 vs. （4.734±0.044） mm2，（4.247±0.069） mm2，P<0.05. Conclusion：The rabbit model of alloxan-induced diabetes and ACL reconstruction is safe，reliable，economic，and stable. There is a significant reduc－tion in BMD of the bone tunnel and the surrounding area in di－abetic rabbits after ACL reconstruction，which results in de－layed growth of the bone tunnel.