大鼠骨骼肌缺血再灌注时血红素氧合酶-1的表达

目的：观察大鼠缺血再灌注时骨骼肌中血红素氧合酶－1（HO－1）表达的变化，方法：夹闭大鼠股动脉造成下肢缺血模型，分别采集假手术（S）组，单纯缺血（I）4小时组及缺血4小时再灌注（R）2、4、8、16和24小时组的比目鱼肌，检测其组织学和丙二醛（MDA）含量变化，通过Northern印迹、Western印迹及免疫组织化学分析，观察HO－1表达的变化。结果：S组和I组未见HO－1mRNA表达；R2组可见其表达信号，且随着再灌注时间延长表达信号逐渐增强，到R8组时达到高峰，之后渐减弱，R24组时已消失。蛋白表达的变化与mRNA变化基本一致，免疫组织化学显示，R组HO－1阳性信号主要出现在骨骼肌细胞浆内，S组和I组均未见阳性信号。与S组相比，R各组MDA含量显著增高（P＜0．05），但R8组较R4组显著减低（P＜0．05）。结论：肢缺血再灌注可诱发骨骼肌HO－1的表达，其表达可能具有保护作用。

EXPRESSION OF HEME OXYGENASE-1 IN SKELETAL MUSCLE AFTER ISCHEMIA-REPERFUSION IN RATS

Objective To observe the changes of heme oxygenase 1 (HO 1) expression in the skeletal muscle after ischemia reperfusion of hind limb in rats. Methods A model of hind limb ischemia was made by clamping femoral artery with a microvascular clip. Soleus muscle was obtained from the animals received sham operation, 4 h ischemia without reperfusion and 2h , 4h ,8h ,16h , 24h reperfusion after 4h ischemia. Soleus histology and malondialdehyde (MDA) content were measured. The levels of HO 1 mRNA and protein were measured in different time by Northern blotting, Western blotting and immunohistochemistry technique. Results After ischemia reperfusion of limb, HO 1 mRNA increased at the 2nd hour, reached a peak at the 8th hour, and returned toward baseline at the 24th hour. The change of protein level was essentially in agreement with that of mRNA. Immunohistochemical results showed that HO 1 expressed primarily in skeletal muscle cytoplasma. There were no positive signals of mRNA and protein in sham group and in ischemia group. After limb reperfusion, MDA contents in the soleus muscle increased significantly when compared with that in the sham group ( P< 0.05). MDA content of the 8th after reperfusion decreased significantly when compared with that of the 4h after reperfusion ( P< 0.05). Conclusion Ischemia reperfusion can induce HO 1 expression in skeletal muscle in rats, which may provide protection for injured tissue.