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目的 探讨血管内皮干细胞(endothelial pregenitor cell,EPC)动员剂AMD3100对糖尿病小鼠颅骨缺损愈合的影响.方法 2型糖尿病小鼠55只,随机分为未手术组(n=5)、实验组(n=25)和对照组(n=25).实验组和对照组均在其颅骨表面制造2个直径3 mm圆形骨缺损,实验组于术后第3天起给予AMD3100腹腔注射,每日10 mg/kg,共15d,对照组给予生理盐水腹腔注射.未手术组处死5只小鼠,实验组和对照组分别于术后1、2、4、8、12周时处死5只小鼠,取外周血测量术前及术后7、14 d小鼠血液EPC含量；取颅骨标本,对术后第4、8、12周标本行micro-CT检查,测量计算骨缺损愈合百分比；对所有标本的脱钙石蜡切片进行HE染色,对术后第1、2、4周标本的冰冻切片行CD31和骨钙素免疫荧光染色,计算成骨区血管密度和成骨细胞密度.采用t检验对数据进行统计学分析.结果 糖尿病小鼠EPC的动员在创伤后1周基本消失,而AMD3100可显著增高创伤后期血液中EPC水平.AMD3100治疗的糖尿病小鼠在术后第8周和第12周时其骨缺损愈合百分比分别为50.5％、50.9％,均高于对照组的34.8％、40.2％,差异具有统计学意义(P＜0.05)；实验组成骨区血管密度和成骨细胞密度在术后1、2、4周均较对照组增加2倍左右,以术后第2周最显著(实验组毛细血管密度2.47％,成骨细胞密度1.22％；对照组分别是6.11％、2.81％).结论 AMD3100可通过增加成骨区血管密度和成骨细胞密度而改善糖尿病小鼠颅骨缺损愈合程度.

Objective To evaluate the effect of endothelial progenitor cells (EPCs) mobilization on the healing of calvarial defect in diabetic mice.Methods 55 type Ⅱ adult male diabetic mice were included in this study.They were randomly divided into three groups:the non-operative group ( n =5 ),the experimental group (n =25 ) and the control group (n =25 ).Two circular bony defects,3 mm in diameter,were created on the parietal bones of the diabetic mice.Intraperitoneal AMD3100 (10 mg/kg;n =25 ) or sterile saline (control group ) was administered daily beginning at post-operative day 3 and continuing for 15 days.5 mice were sacrificed in each group at non-operation,post-operative week 1,2,4,8,12.Circulation EPC level was measured at pre-operation,postoperative day 7 and day 14.Bony regeneration was assessed with micro-CT at post-operative week 4,8 and 12.HE staining was performed on all the decalcified bone samples.Immunofluorescent CD31 and osteocalcin staining was performed on calvarial defects at weeks 1,2,and 4 to assess the vascularity and osteoblast density,respectively.Results The mobilization of EPC in diabetic mice almost disappeared one week after trauma,while AMD3100 could dramatically increase the circulation EPC level for a long time after trauma.Compared to control group,the healing percentage of bony defect in the diabetic mice treated with AMD3100 was obviously increased at post-operative week 8 (50.5％ vs.34.8％ ) and week 12 ( 50.9％ vs.40.2％ ).Calvarial defects of AMD3100-treated mice harvested at 1,2,and 4 weeks demonstrated increased vascularity and osteoblast density,compared to the controls.The difference was most marked in postoperative week 2 (vascularity:6.11％ vs.2.47％ ; osteoblast density 2.81％ vs.1.22％,P ＜0.01).Conclusion AMD3100 can improve the healing of calvarial defect in diabetic mice by increasing the vascularity and osteoblast density at the regeneration area.