Bcl-2及Bax表达与COPD大鼠骨骼肌细胞凋亡的相关性

Study on Relationship between Expressions of Bcl-2 and Bax and Skeletal Muscle Apoptosis in COPD Rats

目的探讨慢性阻塞性肺疾病(COPD)模型大鼠骨骼肌Bc l-2、Bax表达与骨骼肌细胞凋亡的关系。方法 100只健康W istar大鼠随机分为模型组80只,正常对照组(NC)20只。模型组采用熏香烟和气管内滴注猪胰蛋白酶(PEE)法建立COPD模型大鼠,以低于NC大鼠平均体重的90%作为判断发生营养不良的标准,将COPD模型大鼠分为COPD营养不良组(NM)和COPD营养正常组(MC)。取大鼠骨骼肌(膈肌、趾长伸肌)制备石蜡切片,分别采用TUNEL法测定骨骼肌细胞凋亡率,免疫组织化学法测定骨骼肌Bc l-2、Bax表达,Im age-Pro P lus version 6.0图像系统测定Bc l-2、Bax蛋白表达强度。结果 NM大鼠膈肌、趾长伸肌的凋亡率高于NC和MC(P<0.05);NM大鼠膈肌、趾长伸肌Bc l-2的表达均低于NC和MC(P<0.05);NM膈肌、趾长伸肌的Bax表达均强于MC和NC(P<0.05)。结论 COPD模型大鼠可能存在骨骼肌细胞凋亡,Bc l-2、Bax可能参与COPD模型大鼠骨骼肌细胞凋亡。

Objective To study the relationship between expressions of Bcl - 2 and Bax and skeletal muscle apoptosis in COPD rats. Methods 100 healthy male adult Wistar rats were randomly divided into two groups including model group （n = 80） and normal control group （NC,n = 20）. COPD model rats were copied by tabocco smoke inhalation and intracheally given PEE successfully. COPD model rats were redivided into two groups including malnutrition COPD group （MC） which was lower than 90% of the mean body weight of NC and non -malnutrition COPD group（NM）. With keletal muscle（ diaphragmatic muscle and long extensor muscle digits）from all tested rats as experimental materials,the rates of muscle apoptosis, expression of related protein of Bcl - 2 and Bax were measured by TUNEL method,immunohistocbemical method and Image - Pro Plus version 6.0 systerm respectively. Results The rates of muscle apoptosis in both diaphragmatic muscle and long extensor muscle digits of the MC were higher than those of NM and NC （P 〈 0.05 ）. The expression of Bcl -2 in MC was lower than that of NM and NC （P 〈 0.05 ）. The expression of Bax in MC were significantly higher than that of NM and the NC （P 〈 0. 05 ）. Conclusion Apoptosis is the important mechanism of skeletal muscle atrophy in COPD model rats probably. The genes Bcl -2 and Bax are the factors to adjust the muscle apoptosis in COPD model rats.