A control model for tibial cortex neovascularization in the bone chamber.
A control model for tibial cortex neovascularization in the bone chamber.
复制标题
骨腔内胫骨皮质新生血管形成的控制模型。
DOI：
10.1002/jbmr.5650050106
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
Moffat,R
中科院分区：
文献类型：
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作者：
Winet,H;Bao,JY;Moffat,R
使用光学骨腔植入物(BCI)监测兔胫骨皮质间隙缺损处的新生血管形成。在活体和原位观察每周一次，当皮质骨穿透缝隙进入组织间隙时，皮质骨以骨小梁的形式生长。每只兔在移植后3~8周每周用活体显微镜观察。固定视野为缝隙组织间隙，厚100μm，直径2 mm。当血管携带FITC-葡聚糖70被注射到耳静脉时，用表观照明荧光显微镜进行成像。观察结果被录制下来并拍摄下来。用数字图像处理系统对录像带进行分析，得到成纤维细胞颗粒组织和小梁的单位体积血管长度(L/V)、口径C和血流速度随时间的变化。观察结果支持以下结论：(1)新生血管先于新骨形成，(2)主要血管倾向于与胫骨轴线一致，(3)骨结合产生的纤维颗粒组织血管破坏刺激纤维颗粒组织血管生成，使其L/V保持不变，(4)L/Vin小梁随时间增加，(5)愈合小梁的血供(Q̄)与营养交换不呈正相关。因此，仅凭Q̄不能预测小梁的氧气供应，因为营养交换面积不是恒定的。我们注意到，在纤维颗粒组织和骨血管中，潜在的营养交换面积都增加了，而在纤维颗粒组织中，血液的体积分数减少，在小梁中保持不变。
Neovascularization across a gap defect in a rabbit tibial cortex was monitored using the optical bone chamber implant (BCI). Cortical bone growing by apposition as trabeculae was observed weekly as it penetrated a slit into a tissue space in vivo and in situ. Each rabbit was viewed weekly with an intravital microscope from 3 to 8 weeks postimplantation. The constant field of view was the slit‐gap tissue space, which was 100 μm thick and 2 mm in diameter. Vessels were imaged with epi‐illuminated fluorescence microscopy as they carried FITC‐dextran 70 that had been injected into an aural vein. Observations were videotaped and photographed. Videotape frames were analyzed with a digital image processing system to obtain measures of vessel length per unit volume (L/V) of fibroblastic granular tissue and trabeculae, caliber C, and flow velocityu, all as functions of time.Observations supported the conclusions that (1) neovascularization precedes neo‐osteogenesis, (2) major vessels tend to align with the tibial axis, (3) bone apposition‐generated destruction of fibrous granular tissue vessels stimulates fibrous granular tissue angiogenesis, which keeps itsL/Vconstant, (4)L/Vin trabeculae increases with time, and (5) blood supply (Q̄) and nutrient exchange in healing trabeculae are not positively correlated. Thus, O2supply to the trabeculum cannot be predicted from Q̄ alone because the nutrient exchange area is not constant. It was noted that an increase in the potential nutrient exchange area occurred in both fibrous granular tissue and osseous vessels and the volume fraction of blood decreased in the fibrous granular tissue and remained constant in the trabeculae