Effect Of Granulocyte-colony Stimulating Factor On The Injured Endothelium Repair Of Carotid Artery Ballon-injured Atherosclerotic Rabbit

Objective:TO Study the role of recombinant human granulocyte colony-stimulating factor(G-CSF) mobilization bone marrow whether can promote the reendothelialization process of injured atherosclerotic vascular intimal or not,To comprehend about the program whether can inhibit injured vessels neointimal hyperplasia in order to prevent vascular restenosis after interventional therap or not.Methods:35 female New Zealand white rabbits were randomly divided into nomal diet group(n=5) and high-fat feeding group(n=30),the rabbits in nomal diet group fed to the general diet and high-fat feeding group fed high fat diet for 12 weeks,after 10 weeks we randomly selected 20 rabbits from high-fat feeding group and injured right carotid artery by balloon,after balloon injured those rabbits were randomly divided into two groups:the one gruop is interfere with G-CSF(n=10),injection G-CSF:50μg /d,through vein;the other group(n=10) have no interference,injection NS 2ml/d,for 7 day.the remaining 10 rabbits set as the control neither injury carotid artery nor interfere with G-CSF,injection of Ns 2ml/d,for 7 days.After High fat diet fed 10 weeks,we measure TG,LDL,HDL,CHO level in serum;after G-CSF-intervention 7 days,we measured peripheral blood WBC,NEU,MONO,LYM,PLT count.At the 12th week we executed all test animals,and got the right carotid artery,thoracic aorta those with HE to evaluate atherosclerotic rabbit model,sample were also stained by elastic fibers to calculate medial area(M),intima area(I) and ratio of I/M to evaluate the degree of stenosis;Evans blue staining and calculate the area of endothelial regeneration(An),total area of endothlium and the ratio of An/At to assess the rate of reendothelialization;CD31 immunohistochemical staining on local injured vascular endothlium to detect CD31-positive cells to evaluate the effects of G-CSF mobilization EPCs and homing ability of EPCs.Result 1.the rabbits had been fed with High-cholesterol diet for 10 weeks result to evident hyperlipidemia and TG,LDL,CHO,increased in serum compared with ordinary feeding rabbits,there is significantly difference(P＜0.001),thoracic aortic pathology were stained with HE,which reveal the typical pathological changes.on Atherosclerosis 2.after G-CSF mobilize seven days,the rabbit peripheral blood WBC significantly increased and surge to peak levels,with neutrophils and mononuclear cells increased mainly,compared with the other experimental group with no G-CSF mobilization,there is significant statistical difference(p＜0.001),3.compared With no balloon injury experimental group the G-CSF+balloon-injued carotid artery I/M value increased significantly(P＜0.01),the ballon-injured+NS group compared to ballon-injured+G－CSF Group I/M value decreased significantly(P＜0.01).4.the reendothelialization rate of G-CSF+balloon－injued group is significantly higher than the ballon-injured+NS group,there is significantly difference in statistic(P＜0.001).Non-ballon-injured+NS group,endotheliun is complete,the sample can not be stained with Evans Blue,endothelial coverage rate is 100%5.CD31 Immunohistostaining showed that CD31 positive cells in carotid artery were detected in the injured intimal which cover with new endothelial cells,CD31 positive cells are more expression in G-CSF intervention group than the ballon-injured+NS group,there is significant differences in statistical(P＜0.01).Conclusion 1.The method of feeding high-fat diet for 10 weeks can successful make rabbit form atherosclerosis,and permanent Hyperlipemia;atherosclerotic plaque can be seen clearly in pathology 2.Vascular endothelial injury can destruction the integrity of endothelium.which may lead to intima hyperplasia.intima and medial area ratio increased resulted to vascular restenosis.If the reendothelialization progress of injured-endothelium and restore the integrity of endothelium,can be accelerate, intimal hyperplasia will be inhibited effectively.3.G-CSF can mobilize EPCs in bone marrow and home to injured endothlium EPCs not only promote reendothelialization but also inhibit intimal hyperplasia and prevent restenosis effectively after vascular injured.