目的 观察粒细胞-巨噬细胞集落刺激因子(GM-CSF)对大鼠深Ⅱ度烫伤创面愈合过程中血管生成素-1(Ang-1)表达的影响.方法 建立SD大鼠深Ⅱ度烫伤模型,按自身对照的方法将创面随机分为GM-CSF实验组和对照组.分别取伤后1、3、7、14、21 d创面皮肤组织,采用实时荧光定量逆转录-聚合酶链反应(FQ-PCR)分析Ang-1的mRNA表达；免疫组织化学法和Western blot法检测创面Ang-1蛋白的表达；免疫组织化学法检测创面CD31的表达,计算微血管密度(MVD).结果 创面Ang-1的mRNA表达量于伤后1、3d呈下降趋势,实验组(1.44±0.20、0.30 ±0.17)低于对照组(2.36±0.18、1.34±0.24) (P ＜0.05)；之后其表达量逐渐升高,伤后7、14、21 d实验组(4.52±0.21、8.47±0.14、7.52±0.20)均明显高于对照组(2.71±0.12、3.69±0.24、3.07±0.17)(P＜0.05).实验组创面Ang-1的蛋白表达量于伤后1、3d可见显著下降(0.491±0.055、0.181±0.025),与对照组(0.735±0.080、0.436±0.071)比较明显降低(P＜0.05)；之后其表达量持续升高,至伤后14 d达峰值,实验组(0.821±0.060、1.257±0.225、1.126±0.131)较对照组(0.701±0.078、0.825±0.072、0.733±0.073)明显增高(P＜0.05).实验组创面于伤后第3天起见较多CD31阳性血管并逐渐增多,MVD值在伤后3、7、14、21 d(9.5±1.8、23.4±2.9、38.4±3.1、24.6±2.5)均明显高于对照组(4.0±1.9、10.5±2.0、22.9±2.7、15.1±2.6,P＜0.05).结论 GM-CSF降低Ang-1在烧伤创面愈合早期的表达,有利于创面血管新生；促进Ang-1在愈合中、后期表达,利于创面血管成熟,加快创面愈合.%Objective To investigate the influence of granulocyte macrophage colony stimulating factor (GM-CSF) on the expression of angiopoietin-1 (Ang-1) in deep partial thickness burn wound in rats.Methods The models of deep partial thickness burn wounds on the back in Spregue-Dawley (SD) rats were established.The paired wounds on the same rats were randomly divided into GM-CSF treatment (test) and control groups by self-control.Tissue samples were harvested from the wounds on the 1 st,3rd,7th,14th and 21st day respectively after burns.The mRNA expression of Ang-1 was detected by using real-time reverse transcriptase-polymerase chain reaction (FQ-PCR).And the protein expression of Ang-1 was detected by immunohistochemical and western blot,the protein expression of CD31 by using immunohistochemical staining,and the microvascular density was calculated.Results The mRNA expression level of Ang-1 in the burn wounds was decreased slightly on the 1st and 3rd postburn days and that in test group (1.44 ±0.20,0.30 ± 0.17) was lower than that in control group (2.36 ± 0.18,1.34 ± 0.24) (P ＜0.05).Then the Ang-1 mRNA expression was gradually increased on the 7th and 14th postburn days and decreased slightly on the 21st postburn day,and the expression level in the test group at the above time points (4.52 ±0.21,8.47 ±0.14,7.52 ±0.20) was higher than that in control group (2.71 ±0.12,3.69 ±0.24,3.07 ±0.17) (P ＜0.05).The protein expression of Ang-1 was declined remarkably on the 1st and 3rd postburn days,which in test group (0.491 ±0.055,0.181 ±0.025) was lower than that in control group (0.735 ±0.080,0.436 ±0.071) (P ＜0.05).Then the Ang-1 protein expression was gradually increased and reached the peak on the 14th postburn day and the expression in the test group (0.821 ±0.060,1.257 ± 0.225,1.126 ± 0.131) was higher than that in the control group (0.701 ± 0.078,0.825 ± 0.072,0.733 ±0.073) (P ＜0.05).The microvascular number with positive CD31 expression was increased evidently from the 3rd postburn day in test group,and the counting of MVD was remarkably higher in the test group (9.5±1.8,23.4±2.9,38.4±3.1,24.6±2.5) than in the control group (4.0±1.9,10.5±2.0,22.9 ±2.7,15.1 ±2.6) on the 3rd,7th,14th and 21st days respectively after burns (P ＜0.05).Conclusion GM-CSF inhibits the mRNA and protein expression of Ang-1 during the early stage of wound healing,which can be beneficial to the angiogenesis.And GM-CSF boosts Ang-1 expression during the middle and late stages of wound healing.This would be helpful to wound vascular maturation and wound healing.
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