运动对制动大鼠骨骼肌中雄激素受体的影响

An experimental study of the exercise effect on androgen receptor of skeletal muscle in immobilized rats

目的 :探讨在废用性肌肉萎缩和康复过程中骨骼肌雄激素受体 (androgenreceptor,AR)的变化 ,以及不同的康复锻炼方式对肌萎缩恢复的作用。方法 :将 30只雄性SD大鼠随机分为 5组 :A组 ,正常对照组 ;B组 ,外固定 3周后即刻宰杀组 ;C组 ,外固定 3周后自然恢复 3周组 ;D组 ,外固定 3周后跑台训练 3周组 ;E组 ,外固定 3周后游泳训练 3周组。以葡聚糖包裹活性炭吸附法测定AR结合容量。结果 :外固定 3周后 ,大鼠股四头肌组织的AR结合容量 (7 99± 2 19fmol/mg)较正常对照组 (11 6 1± 2 96fmol/mg)显著下降 ;自然康复组的AR结合容量 (10 41± 3 90fmol/mg)无明显变化。运动组的AR结合容量较对照组及自然康复组均有显著增高 ,以跑台组 (2 5 70±7 5 3fmol/mg)增高的幅度更大。结论 :外固定造成萎缩肌组织的AR结合容量显著下降 ;适宜的运动训练可以通过提高局部肌肉组织的AR结合容量加速肌萎缩的康复进程 ;雄激素对骨骼肌AR的正相调节作用是运动后AR水平增高的原因之一。

Objective:To investigate the capacity of androgen receptor (AR) binding in skeletal muscle after disuse,natural recovery and exercise in male rats.Method: The way we used was dextran coated charcoal assay.Result:The AR binding capacity (7 99±2 19 fmol/mg) in quadriceps femoris muscle decreased significantly compared with the control (11 61±2 96 fmol/mg) after three weeks of immobilization of lower limbs in rats.The AR binding capacity (10 41±3 90 fmol/mg) of natural recovery group had no distinct change.The AR binding capacity of both moderate intensity of treadmill group and swimming group (25 70±7 53 fmol/mg, 14 79±0 76 fmol/mg respectively) were higher than that of the control and natural recovery group. The result of treadmill group was the best.Conclusion:Immobilization could significantly decrease the AR binding capacity of skeletal muscle.A suitable exercise can accelerate the course of rehabilitation by enhancing AR binding capacity of local muscle tissues. The AR binding capacity of skeletal muscle could be positively regulated by androgen,which might be one of the increasing factors of AR after exercise.