成骨细胞对流体剪切力的响应受流体持续时间和流速的影响  

Response of osteoblasts to fluid shear stress is duration and rate dependent

作　　者：伍颖颖[1] 

机构地区：[1]四川大学华西口腔医院口腔种植中心,四川成都610041

出　　处：《中国口腔种植学杂志》2011年第1期7-8,共2页Chinese Journal of Oral Implantology

摘　　要：当骨组织受到外界力作用时会调节自身的结构和质量以适应此机械刺激,种植体周围的骨由有机及无机成分构成,而且其中细胞对外界刺激产生响应。骨组织这种将应力刺激信号转化为细胞生物化学信号的过程就称为动力传导,而成骨细胞对流体剪切力的应答过程实际就是动力传导过程。那么种植后即刻加载在种植体周围骨组织中产生的应力能否促进新骨的形成呢?为了了解成骨细胞对不同的持续时间流动流体刺激的响应,本实验将成骨细胞接种在部分脱蛋白三维支架材料上,然后在不同环境下进行培养:持续流体灌注培养、间断流体灌注培养和静态培养。培养至第4、8、12天时分别收集样本进行分析检测:通过细胞计数CCK-8和扫描电镜实验观察成骨细胞增殖状况;成骨细胞分化的标志性物质,如碱性磷酸酶的活性和骨钙素的表达量通过qRT-PCR和碱性磷酸酶活性检测实验进行检测;并且通过测定支架材料上的钙沉积来比较细胞矿化状况。实验结果证实流动流体在刺激成骨细胞性能方面起着重要作用,它能够促进细胞增殖;增加细胞分泌的钙沉积;并且提高成骨细胞标志性物质的表达。此外,本实验还观察到相对于间断灌注培养和静态培养,持续的流体灌注培养更加有助于激活成骨细胞活性。虽然成骨细胞对外界机械刺激响应的机制相当复杂而且至今尚未完全阐明,但是本实验表明持续的流体灌注对激活成骨细胞活性起着重要作用。因此我们得出结论:流体灌注的持续时间和流体流速是影响成骨细胞性能的重要影响因素。为进一步研究种植体的即刻负载提供了理论基础。It is well known that bone can adjust its structure to become better suited to withstand the mechanical demands it experiences.The bone around the implant consisting of a structured extracellular matrix （ECM） composed of inorganic and organic elements containing a conglomeration of cell types responsible for its metabolism and upkeep in response to a variety of signals.The process of mechanotransduction,the conversion of a mechanical stimulus into a biochemical response,is known to occur in osteoblasts in response to fluid shear stress.So we wonder whether immediate loading would induce the formation of new bone.In order to understand reaction of osteoblasts to various duration of flow perfusion,we seeded osteoblasts on three-dimensional pratial deproteinized bone scaffolds.And then the cell/scaffold constructs were cultured in the following conditions： continuous flow perfusion,intermittent flow perfusion,and static condition.Samples were collected on day 4、8、12 for analysis.The osteoblasts proliferation was demonstrated by cell counting kit-8 and scanning electron microscopy assay,known markers of differentiation,including activity of alkaline phosphatease,expression of osteocalcin,were tested by qRT-PCR and alkaline phophatease activity assay,and deposition of calcium were used as indicators mineralization demonstrated by calcium content assay.The results supported the fact that fluid flow play an important role in the activation of osteoblasts： enhance the cell proliferation,increase calcium deposition secreted by cells,and promote the expression of osteoblastic markers.Additionally,we found continuous flow perfusion a more favorable environment for initiation of osteoblasts activity compared with intermittent flow perfusion.Although the mechanism by which osteoblasts respond to their changing mechanical environment might be complex and has not been fully elucidated,our results clearly indicated that continuous flow perfusion plays an essential role for the activation of osteoblasts.So we conclude

关 键 词：成骨细胞增殖 流体剪切力 持续时间 种植体周围骨组织 流速 酶活性检测 三维支架材料 成骨细胞活性 

分 类 号：R329[医药卫生—人体解剖和组织胚胎学]