【摘要】 目的探讨正常血供及缺血状态下小鼠后肢肌肉氧分压水平及其与HIF-1α蛋白表达的关系,为血管新生的体外低氧研究提供理论基础。方法选用成年雄性Balb/c小鼠30只〔体质量(20±2)g〕制备小鼠后肢缺血模型,实验分为正常对照组和缺血24 h、1周、2周及3周组,检测各组小鼠双侧后肢腓肠肌和股骨骨髓的氧分压,并对不同缺血时间的腓肠肌组织中HIF-1α蛋白表达水平采用Western blot法进行检测。结果腓肠肌及股骨骨髓正常的氧分压基线水平分别为(47.78±4.37)mm Hg和(21.55±3.40)mm Hg(1 mm Hg=0.133 k Pa)。不同缺血时间组小鼠患肢腓肠肌组织的氧分压均较健侧明显下降(P<0.05),并在缺血1周时达到最低,此时肌肉组织的炎症反应也最严重,HIF-1α蛋白的表达水平也最高;随着缺血时间的延长,腓肠肌组织的氧分压有所回升,HIF-1α蛋白表达水平也下调,但肌肉组织HIF-1α蛋白的表达与氧分压的相关性无统计学意义(r=-0.86,P>0.05)。股骨骨髓的氧分压在不同缺血时间点的变化不明显。结论缺血组织HIF-1α蛋白的表达水平能够反映肢体的缺血程度;不同组织的生理氧分压水平不同,为组织细胞的体外低氧研究提供了依据。更多还原

【Abstract】 Objective To explore the relationship between the oxygen partial pressure of mice hindlimb muscles with normal blood supply or ischemia and expression of HIF-1α protein, and to provide a theoretical basis for the study of angiogenesis in vitro hypoxia. Methods Mice hind limb ischemia model were established, tissue oxygen tension of gastrocnemius muscle and bone marrow were measured by micro electrode at different time points of ischemia(24 hours,1 week, 2 weeks, 3 weeks, and unoperated as control). Protein level of hypoxia inducible factor-1α and histological examination were performed on gastrocnemius muscle as well. Results The oxygen tension baselines of gastrocnemius muscle and femoral bone marrow was(47.78±4.37) mm Hg and(21±3.40) mm Hg, respectively. Muscle oxygen tension decreased significantly at all time points after modeling(P<0.05), and reached lowest level in 1 week of ischemia. The inflammatory reaction was most serious and HIF-1α protein reached highest level at the same time point. With the extension of ischemic time, the tissue oxygen tension recovered while HIF-1α level was down-regulated, however, There was no statistical correlation(r=-0.86, P>0.05). Oxygen tension in bone marrow didn’t show any significant change at all time points. Conclusions The expression level of HIF-1α protein in ischemic tissue can reflect the degree of ischemic limb. The concept that physiological oxygen level differs in different tissue is highlighted, and may provide basis for ex vivo hypoxic research.更多还原