G-CSF对动脉粥样硬化兔颈总动脉球囊损伤后内皮修复的影响

目的研究重组人粒细胞集落刺激因子（G-CSF）的骨髓动员作用能否促进动脉粥样硬化性血管内膜损伤后的再内皮化过程,来预防损伤血管再狭窄.方法将35只新西兰雌性大白兔,随机分为正常饲养组（对照组）5只;高脂饲料喂养组30只在喂养10周后随机抽取20只行右颈总动脉囊扩张损伤,术后随机将其分为：G-CSF干预＋损伤组（n=10）,予静脉注射G-CSF50μg/d,连续7d,NS＋损伤组（n=10）,术后静脉注射生理盐水2mL/d,连续7d;第12周处死所有试验动物,取右颈总动脉、胸主动脉行HE染色观察血管粥样硬化病变评价模型制作情况,弹力纤维染色计算内膜（）I、中膜面积（M）比值I/M以评价内膜增生程度;伊文氏蓝染色并计算内皮再生面积（An）、内皮总面积（A）t比值An/At以评价再内皮化率;CD31免疫组化染色检测损伤局部CD31细胞表达的阳性率以评价G-CSF对EPCs动员效果以及EPCs对受损内皮的修复情况.结果 （1）高脂饲料喂养12周后可形成典型的动脉粥样硬化斑块.（2）G-CSF＋损伤组与NS＋损伤组相比I/M值降低,差异有统计学意义（P〈0.01）.（3）An/At明显升高,有统计学意义（P〈0.01）.（4）免疫组织化学染色显示颈动脉内皮CD31细胞表达阳性率G-CSF＋损伤组高于NS＋损伤组,有统计学意义（P〈0.01）.结论 G-CSF可以动员骨髓EPCs到外周血并迁移到血管内膜受损部位,促进再内皮化,抑制内膜增生,有效预防血管损伤后再狭窄的发生。

Effect of G-CSF on the Injured Endothelium Repair of Carotid Artery Ballon-injury Atherosclerotic Rabbits

Objective To study whether recombinant human granulocyte colony-stimulating factor（G-CSF） can promote the reendothelialization process of injured atherosclerotic vascular intimal and prevent restenosis of injured blood vessels.Methods Thirty-five female New Zealand white rabbits were randomly divided into nomal diet group（n=5） and high-fat feeding group（n=30）.We randomly selected 20 rabbits from high-fat feeding group after 10 weeks and injured the right carotid artery with balloon,after balloon injury those rabbits were randomly divided into two groups：G-CSF＋ ballon-injury group（n=10）,rabbits were injected intravenously 50 μg/d G-CSF for 7 days;ballon-injury＋NS group,rabbits were injected intravenously 2 mL/d NS for 7 days.We measured TG,LDL,HDL,CHO levels in serum;7 days after G-CSF-intervention,we measured peripheral blood WBC,NEU,MONO,LYM,PLT count.At the 12th week we executed all animals,and got the right carotid artery and thoracic aorta.Samples were stained with HE to evaluate atherosclerotic rabbit model.Samples were also stained by elastic fibers to evaluate the degree of stenosis by calculating medial area（M）,intima area（）I and ratio of I /M.Sample were also stained with Evans blue to assess the rate of reendothelialization by calculating the area of endothelial regeneration（An）,total area of endothlium and the ratio of An/At.CD31 immunohistochemical staining on local injured vascular endothlium was used to detect CD31-positive cells and evaluate the effects of G-CSF mobilization EPCs and homing ability of EPCs.Results（1） The typical atherosclerotic plaques formed in rabbits after high-fat feeding for 12 weeks.（2） The I/M of rabbits was lower in G-CSF＋ballon-injury group than in ballon-injury＋NS group（0.10±0.04 vs.0.31±0.09,P〈0.01）.（3） The An/At ofrabbits was significantlyhigher in G-CSF＋balloon-injued group than in ballon-injury＋NS group（85.60±3.25 vs.14.76±3.31,P〈0.01）.（4） CD31 Immunohistostaining showed that CD31 positive cells were more in G-CSF ＋balloon-injued group than the ballon-injury＋NS group（0.83 ±0.08 vs.0.22 ±0.04,P 0.01）.Conclusion G-CSF can mobilize EPCs in bone marrow to peripheral blood and migrate to injured endothelium,and not only promote reendothelialization but also inhibit intimal hyperplasia and prevent restenosis effectively after vascular injury.