目的探讨三突变型低氧诱导因子－1α（ HIF－1α）基因对老年鼠缺血下肢的血管新生效应。方法24只老年小鼠结扎一侧下肢股动脉制备下肢缺血模型并随机等分为3组，分别经肌肉注射生理盐水（ NS）、腺病毒包裹的β－半乳糖苷酶基因（ Ad－LacZ）、腺病毒包裹的Pro402、Pro564、Asn803三位点突变型HIF－1α基因（ Ad－TM）。术前、术后0、7、14、21、28 d分别对小鼠双侧下肢骨骼肌行对比超声灌注成像评价缺血下肢骨骼肌的血流情况（用缺血下肢血流量／对侧非缺血下肢血流量表示）。术后28 d处死小鼠取下肢骨骼肌行免疫荧光染色标记Bandeira simplificifolia－1凝集素（ BS－1 lectin）评价微血管密度（用微血管／骨骼肌纤维表示）。结果对比超声灌注成像显示：术前双下肢血流量基本相等，术后0 d 3组的血流量均下降至15％左右，3组之间差异无统计学意义（ P＞0.05）。随着时间的推移，3组的血流均有所恢复，其中，Ad－TM组的血流恢复快于其他两组，术后28 d，Ad－TM组中缺血下肢的血流量达到对侧非缺血下肢血流量的（66.6±8.9）％，较NS组的（34.2±6.3）％和Ad－LacZ组的（35.7±5.4）％显著增加，差异有统计学意义（P＜0.01）。免疫荧光染色显示：Ad－TM组的微血管密度1.06±0.10显著高于NS组0.36±0.04和Ad－LacZ组0.35±0.04，差异有统计学意义（P＜0.01）。结论三突变型HIF－1α基因可有效促进老年鼠缺血下肢血管新生。%Objective To explore the angiogenic effects of the HIF -1αwith triple-point mutations in hind -limb ischemia in aged mice .Methods Twenty-four aged mice under unilateral artery ligation were randomly divided into 3 test groups, in which normal saline, adenovirus (Ad) vector particles containing the gene for LacZ (Ad-LacZ), and HIF-1a 402/564/803 (triple-point mutant, Ad-TM) were intramuscularly injected into the ischemia hind limb , respectively .Serial contrast-enhanced ultrasonic perfusion imaging of the proximal adductor muscles in the ischemia and contralateral non-ischemia hind limbs was performed .On Day 28 postoperatively , the muscle specimens were harvested and the density of the capillaries was determined by immunofluorescence analysis using antibodies against Bandeira simpli -ficifolia-1 lectin ( BS-1 lectin) .Results Immediately after femoral artery ligation , blood flow ( as a percentage of that in the non-ischemia hind limb) was reduced to 15%in all groups (P>0.05).Although blood flow gradually recovered over time in all groups , recovery was persistently better in the Ad -TM group as compared with the other groups .On Day 28, the blood flow ratio was significantly increased in the Ad -TM group [(66.6 ±8.9)%] as compared with NS group [(34.2 ±6.3)%] and Ad-LacZ group [(35.7 ±5.4)%] (P<0.01).Capillaries density (expressed as capillary/muscle fiber) in Ad-TM group was 1.06 ±0.10, significantly superior to those in NS group (0.36 ±0.04) and Ad-LacZ group (0.35 ±0.04) (P<0.01).Conclusion The angiogenic effects were enhanced in aged mice hind -limb is-chemia by using HIF-1αwith triple-point mutations .
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