静力性负荷所致损伤对大鼠骨骼肌TGF-β1表达的影响

The Influence of Injury due to Static load on the Skeletal Muscle Expression of TGF-β1

为探讨TGF-β1在骨骼肌静力性损伤后修复和再生过程中的作用机制,选用雄性SD大鼠72只,随机分为对照组、3天~4周实验组,对各实验组大鼠踝关节施加50%体重负荷进行后肢跖屈位支撑站立,造成腓肠肌静力性损伤。采用逆转录-聚合酶链反应和免疫组化方法,观察腓肠肌TGF-β1在转录和翻译水平的表达。结果：TGF-β1在转录和翻译水平的表达均显著增强,但转录水平表现为第3天~2周时升高,第3周时回落,至第4周时又急剧升高,而翻译水平表现为阳性面积在第1周时达到高峰,随后下降,而阳性灰度强度在第3天~2周时处于稳定水平,随后显著升高。结论：TGF-β1参与调节骨骼肌静力性损伤后的再生和修复,TGF-β1 mRNA表达上调在早期和中期主要是导致TGF-β1蛋白分布更加广泛,在后期主要是引起局部TGF-β1蛋白浓度的升高。

To investigate the function and mechanism of TGF-β1 on the repair and regeneration of the skeletal muscle after static injury,72 male SD rats were randomly divided into control group and experimental group from 3 days to 4 weeks.It imposed the load of 50% rat＇s body weight on the anckle of the rats and force the hindlimb plantar flexion support stand to yield a result of static calf injury. It adopted the method of reverse transcription-polymerase chain reaction and immunohistochemistry to observe the gastrocnemius TGF-β1 levels in the expression of transcription and translation.Results：TGF-β1 levels in the expression of transcription and translation were significantly increased,but the transcription level of performance increased in from the first 3 days to the second week,declined in the third week and roarred in the fourth week.The translation level is reflected in the summit of the positive area in the first week and deline in the following time.The positive gray scale intensity remained stable from the third day to the second weeks and then significantly increased.Conclusion：TGF-β1 involved in the regulation of skeletal muscle static regeneration and repair after static injury.TGF-β1 mRNA expression increased in the early and middle period and led to wider distribution of the TGF-β1 protein and in the later period led to the increase of the concentration level of the TGF-β1 protein.