压力影响干细胞向兔椎间盘内迁移的初步研究

Preliminary Study on Continuous Pressure Affect Stem Cells Migration to Rabbit Intervertebral Disc

目的:初步观察持续压力对兔椎间盘内干细胞迁移和分布的影响。方法:构建体内可控轴向压力致兔腰椎间盘退变模型,并将其分为4组:正常对照组(假手术组)、轻度压力组(19.6N)、中度压力组(39.2N)及重度压力组(78.4N),同时给予口服5-溴脱氧尿嘧啶核苷(BrdU)喂养2周。在给予加压4周后行BrdU免疫荧光染色,观察和计数各组椎间盘外层纤维环、内层纤维环及干细胞巢区域的标记滞留细胞(LRCs)。结果:与对照组相比,轻度压力组在纤维环外层、纤维环内层及干细胞巢区域LRCs阳性细胞数明显增加,差异均具有统计学意义(P<0.05);相反,重度压力组在上述三个区域的LRCs阳性细胞数明显降低,差异均具有统计学意义(P<0.05)。结论:持续压力能够影响椎间盘内不同区域的干细胞数量,其影响作用的不同与压力强度有关。

Objective：To investigate the effects of continuous pressure on the migration and distribution of rabbit intervertebral disc-derived stem cells. Methods：A controllable pressure-induced rabbit lumbar intervertebral disc degeneration model was adopted to impose various pressured on rabbit IVD in vivo. The survived animals were randomly divided into 4 groups. The IVDs were treated with no pressure as control （control group）, with 19.6N （mild pressure group）, 39.2N （moderate pressure group） and 78.4N （severe pressure group） for four weeks. Rabbits were exposed to BrdU diluted in the drinking water after the start of imposing pressure for two weeks. LRCs were observed and counted in the stem cell niche area and the annulus fibrous outer and inner areas. Results： The LRCs in the stem cell niche and annulus fibrous outer regions and inner areas were increased significantly in discs from the mild pressure group compared with controls （P〈0.05）. In contrast, the LRCs numbers of severe pressure group in these areas of discs above decreased obviously compared with controls （P〈0.05）. Conclusion： Continuous pressure was shown to have different effects on the stem cell numbers in IVDs, with involvement of various disc regions, indicating a differential response by disc tissue to continuous pressure depending on the intensity of pressure.