不同强度跑台运动对大鼠软骨下骨三维结构的影响

Effects of treadmill running at different intensities on three-dimensional structure of rat subchondral bones

目的探讨不同强度跑台运动对大鼠胫骨软骨下骨三维结构的影响。方法采用随机数字表法将24只雌性SD大鼠分为对照组、低强度跑步组、中强度跑步组及高强度跑步组。3个运动组大鼠根据各自运动方案进行跑步训练，对照组大鼠不给予特殊运动训练。于实验进行8周后取各组大鼠胫骨近端组织进行Micro-CT扫描分析。结果与对照组比较。高强度运动组软骨下骨板变厚、骨密度增加、孔隙率降低；软骨下骨松质骨骨小梁数量增加并多呈现板状结构改变；而低强度组和中强度组胫骨软骨下骨未见明显改变。结论跑台运动对大鼠软骨下骨显微结构的影响具有强度依赖性；高强度跑步能导致胫骨软骨下骨结构显著改变。

Objective To explore the effect of treadmill running at different intensities on three-dimensional structure of rat subchondral bones. Methods A total of 24 female Wistar rats were randomly assigned into a sedentary （SED） group, a low-intensity running （LIR） group, a medium-intensity running （MIR） group, or a high-intensity running （HIR） group, each of 6. Rats in LIR, MIR and HIR groups underwent treadmill running exercises with respective protocol, while rats in SED group serve as controls. Eight weeks later, all animals were sacrificed and their proximal end of tibia was examined using Micro-CT. Results Compared with SED group, in HIR group the subchondral plate became thicker with higher BMD and lower porosity, while trabecular bone became more and denser with higher BMD and a more plate-like architecture. LIR and MIR failed to result in considerable changes in the microstructure. Conclusion Treadmill running has an intensity-dependent effect on the three-dimensional structures of subchondral bones. High-intensity running can evoke significant structural changes in subchondral bones.