超声破坏微泡促进下肢缺血大鼠骨骼肌血管新生的时间-效应关系研究

The time-effect relationship of angiogenesis induced by ultrasound-mediated microbubble destruction in the ischemic skeletal muscle of hindlimb of rats

目的探讨超声破坏微泡促进下肢缺血大鼠骨骼肌血管新生的时间-效应关系。方法将76只切断双侧股动脉一周后的SD大鼠随机分为4组:超声破坏微泡组、单纯超声组、单纯微泡组和对照组。超声破坏微泡组经尾静脉输入脂质全氟丙烷微泡造影剂0.5 ml,同时用1.0 MHz、2.0 W/cm2的超声在其双侧大腿骨骼肌局部作用3 min;单纯超声组仅在骨骼肌局部用同等的超声能量作用;单纯微泡组仅由尾静脉输入脂质全氟丙烷微泡造影剂0.5 ml;对照组不作任何处理。处理结束后的第3、7、10、14、21、28天,用免疫组化、酶联免疫吸附试验(ELISA)、彩色多普勒血流显像(CDFI)和国产DFY-Ⅱ型超声图像定量分析诊断仪等方法检测和观察微血管密度(MVD)、血管内皮生长因子(VEGF)的表达和血管新生的情况。结果超声破微泡组有较多的新生血管,其他三组较少;随着时间的变化,超声破坏微泡组的MVD值和VEGF表达在第10天达到高峰,单纯超声组的高峰出现在第14天;CDFI检查和DFY-Ⅱ型诊断仪分析表明,超声破坏微泡组可探及较多的血流信号(P<0.05)。结论超声破坏微泡可刺激缺血骨骼肌中内源性VEGF较快、较多的分泌,从而促进新生血管生成。

Objective To investigate the time-effect relationship of angiogenesis induced by ultrasound-mediated microbubble destruction in the ischemic skeletal muscle of rats. Methods Femoral ateries of 76 SD rats were cut off by operation. One week later, the rats were divided into 4 groups： ultrasound-mediated microbubble destruction group, ultrasound group, microbubble alone group and control group. In ultrasound mediated microbubble destruction group, microbubbles were injected by vein at the dose of 0.5 ml and the target skeletal muscle was radiated by ultrasound at the intensity of 2.0 W/cm^2. In ultrasound group, the target skeletal muscle was radiated by ultrasound at the intensity of 2.0 W/cm^2. In microbubble alone group, microbubbles were injected by vein at the dose of 0.5 ml. The control rats were not treated by ultrasound or microbubbles. On the 3rd, 7th, 10th, 14th, 21st and 28th day after the treatment,immunohistochemistry staining, enzyme linked immunosorbent assay （ELISA）, color doppler flow imaging （CDFI） and DFY- Ⅱ Ultrasound Imaging Analysis Software were used to observe and detect the microvascular density （MVD）, the expression of vascular endothelial grouth factor （VEGF）and angiogenesis. Results Angiogenesis was significant in ultrasound-mediated microbubble destruction group, but a little in other three groups. MVD and VEGF expression of ultrasound-mediated microbubble destruction group arrived at a peak on the 10th day as well as on the 14th day of ultrasound group. CDFI and DFY-Ⅱ software detected much more blood flow signal in ultrasound-mediated microbubble destruction group （P〈0.05）. Conclusion Ultrasound-mediated microbubble destruction can enhance the endogenous secretion of VEGF quickly and more,and accelerate the angiogenesis in the ischemic skeletal muscle.