应用缓释BrdU检测前腭缝成骨细胞的增殖活性  

Proliferative responses of osteoblasts in expanding pre-maxillary suture determined using sustained-release bromodeoxyuridine

作　　者：周洁[1] 李允武[2] 刘海霞[1] 徐疾[1] 唐国华[1] 

机构地区：[1]上海交通大学医学院附属第九人民医院.口腔医学院口腔正畸科上海市口腔医学重点实验室,上海200011 [2]上海交通大学医学院附属第九人民医院药剂科,上海200011

出　　处：《上海口腔医学》2011年第2期147-151,共5页Shanghai Journal of Stomatology

基　　金：上海市科学技术委员会基金(08DZ2271100;10QH1401600);上海市重点学科建设项目(S30206);上海市教育委员会基金(09YZ75)~~

摘　　要：目的:配制缓释BrdU,用于检测前腭缝牵张成骨过程中成骨细胞的增殖和分化,探讨前腭缝牵张成骨的机制。方法:用泊洛沙姆温敏凝胶配制缓释BrdU,大鼠皮下注射后不同时间点采取血样,高效液相色谱法测定BrdU血药浓度,并与腹腔注射BrdU溶液进行比较。选取35天龄雄性SD大鼠40只,随机分为实验组和对照组,实验组安放扩大簧牵张前腭缝。2组动物于24h后随机皮下注射BrdU温敏凝胶1次或腹腔注射BrdU溶液1次。所有动物分别于48h和96h处死(n=5),免疫组化染色检测细胞的增殖和迁移。结果:皮下注射BrdU温敏凝胶6h后,血清中仍可检测出1.21μg/mL BrdU,免疫组化染色可见大鼠前腭缝有BrdU阳性的增殖细胞。腹腔注射BrdU溶液3h后,血清中仅检测到0.17μg/mL BrdU,免疫组化染色未见BrdU阳性细胞。前腭缝牵张48h后,骨缝边缘可见大量BrdU阳性成骨细胞;96h后可见部分BrdU阳性细胞包埋于骨缝边缘的新生骨基质中。结论:BrdU温敏凝胶能起到良好的缓释效果,为体内标记成骨细胞提供了一种简便易行的方法。牵张力作用于前腭缝后,促进骨缝边缘的间充质细胞增殖,这些细胞分化为成骨细胞并分泌骨基质,从而促进新骨形成。PURPOSE： The purpose of this study was to examine the proliferative responses of osteoblasts in expanding pre-maxillary suture using sustained-release bromodeoxyuridine（BrdU）.METHODS： Poloxamer thermosensitive BrdU gel was prepared and injected to the rats subcutaneously.Blood samples were collected and subjected to high performance liquid chromatography（HPLC） for quantitative determination of BrdU levels in serum.Blood samples collected from rats received a single intraperitoneal injection of BrdU solution were served as control.Forty male Sprague-Dawley rats,35 days of age,were randomly allotted into the experimental and control groups.Experimental animals were subjected to pre-maxillary suture expansion by helix spring.Both groups were given either a single intraperitoneal injection of BrdU solution（10mg/100g） or a single subcutateous injection of thermosensitive gel（10mg/100g） after 24 hours.Animals in each group were sacrificed at 48h and 96h（n=5）.Proliferative cells were identified by BrdU immunostaining.RESULTS： 6h after subcutaneous injection of BrdU thermosensitive gel,1.21μg BrdU per mL serum was still identified.BrdU immunostaining also showed labeled proliferating cells in pre-maxillary suture.On the other hand,3h after intraperitoneal injection of BrdU solution,little trace of BrdU（0.17μg/mL） could be detected.BrdU immunostaining did not show labeled cells in pre-maxillary suture.48h after inter-premaxillary suture expansion,a plenty of BrdU labeled osteoblasts were present along the suture-bone interface.96h after expansion,some of these labeled cells were embedded in the newly formed bone matrix.CONCLUSIONS： Sustained-release BrdU thermosensitive gel could be used practically and effectively to label proliferative osteoblasts in vivo.Mechanical stretch stimulates proliferation of osteoprogenitor cells,which then differentiate into osteoblasts and secret bone matrix,leading to new bone formation in the suture.

关 键 词：成骨细胞 增殖 缓释BrdU 前腭缝 牵张力 

分 类 号：R780.2[医药卫生—口腔医学]