磷酸三钙陶瓷材料形状对大鼠体内成血管化的影响

背景:组织工程人工骨支架材料的大体和微观结构可加速血管化进程.目的:观察不同形状β-磷酸三钙陶瓷骨在体内的血管化程度,探索载体材料形状对体内血管化的影响.方法:将柱状和管状两种β-磷酸三钙陶瓷骨材料分别植入SD大鼠两侧腰背筋膜下.结果与结论:①同位素扫描结果:术后第3,6,12周,管状β-磷酸三钙陶瓷骨材料放射性核素骨显影放射性计数明显高于柱状β-磷酸三钙陶瓷骨材料(P <0.05),并且随着时间的延长,两组放射性核素骨显影放射性计数均呈上升趋势.②扫描电镜观察结果:第3周时,材料外形保持良好,宿主纤维组织和血管由材料外周向内生长;术后6周时,管状材料内小血管增生活跃,且分布比较均匀,柱状材料血管增生主要集中在外周部分;术后12周时,两组材料血管化程度更高,管状材料外周及中心部位均可见较为成熟的纤维组织和丰富血管网,但柱状材料纤维组织和血管主要集中在外周部分,中轴部分较少.表明管状三维结构β-磷酸三钙陶瓷骨材料较柱状材料更利于体内血管化.

Effects of different shapes of beta-tricalcium phosphate ceramics on vascularization in vivo of rats

BACKGROUND:The gross and microscopic structure of artificial bone scaffold materials for tissue engineering can accelerate the process of vascularization.OBJECTIVE:To investigate the degree of vascularization in vivo by using different shapes of β-tricalcium phosphate ceramics,to explore the degree of blood vessels,and to explore the effect of the scaffold materials shapes on vascularization in vivo.METHODS:Columnar and tubular β-tricalcium phosphate ceramics were implanted in the bilateral back fascia of SD rats.RESULTS AND CONCLUSION:Radioisotope scan results showed that at weeks 3,6 and 12 after surgery,the radioactive counting in radionuclide bone imaging of tubular β-tricalcium phosphate ceramics was higher than that of columnar β-tricalcium phosphate ceramics(P < 0.05).Besides,the radioactive counting in radionuclide bone imaging was increased with time.The result of scanning electron microscopy indicated that at week 3,the shapes of materials kept well;furthermore,host fiber tissue and vein grew from the periphery of materials to inside;at week 6 after surgery,vascular proliferation was active in tubular β-tricalcium phosphate ceramics and widely distributed.Vascular proliferation in columnar β-tricalcium phosphate ceramics was mainly centralized in periphery.At week 12 after surgery,the degree of vascularization in the columnar and tubular β-tricalcium phosphate ceramics was higher,and mature fiber tissues and abundant vascular net were seen in the periphery and center of tubular β-tricalcium phosphate ceramics.While fiber tissues and blood vessel in columnar β-tricalcium phosphate ceramics were mainly centralized in the periphery,and centre shaft were less.These findings suggest that tubular β-tricalcium phosphate ceramics was more helpful to vascularization in vivo than columnar β-tricalcium phosphate ceramics.