多光谱小动物活体成像技术在骨性关节炎模型评价中的应用

Application of multispectral animal living imaging technology in evaluating osteoarthritis model

目的:利用多光谱小动物活体成像技术动态观察和评价大鼠骨性关节炎模型的应用价值。方法:取3月龄SD雄性大鼠15只(180±20)g,利用碘乙酸关节腔注射法建立骨性关节炎模型:左膝关节腔注射碘乙酸50μl建立OA模型组,右膝关节腔注射等量无菌生理盐水做为正常对照。分别于建模2、4周时进行X-ray活体成像观察,测算骨密度。4周后处死大鼠,取双侧关节进行组织病理学观察,X线和组织病理学参考Kellgren-Lawrence和Collins进行分级。结果:OA模型造模成功,活体成像观察发现与对照组相比,模型组出现关节面不平整、骨赘形成、关节变形、软骨缺损等典型骨性关节炎表型,并伴有股骨远端骨密度下降明显(P<0.01),胫骨近端骨密度下降不明显(P>0.05),病理学结果一致;2周后模型组膝关节接近Collins 1级、Kellgren-Lawrence 2级,4周后模型组膝关节接近Collins 4级、Kellgren-Lawrence 3级;对照组关节面平整,关节间隙正常,软骨未见明显缺损,Collins及KellgrenLawrence 0级,股骨远段及胫骨近端骨密度正常。结论:多光谱小动物成像技术可用于骨性关节炎模型的影像学活体动态观察及骨密度检测,对骨性关节炎模型评价和相关研究具有重要意义。

Objective： To observe application value of multispectral animal living imaging technology in rats model of osteoarthritis. Methods：Fifteen male SD rats weighed （180±20） g （3 months old） were received intra-articular injection of iodoacetic acid for establishing osteoarthritis. Articular cavity of left knee of rats were injected into 50 μl iodoacetic acid. The same volume of sterile saline was injected into right knee articular cavity as control. X-ray living imaging and bone mineral density were observed at 2 and 4 weeks after establishment of model. After 4 weeks, rats were sacrificed and their bilateral joints were collected and determined histologically based on Collins classification and Kellgren-Lawrence classification. Results：Osteoarthritis model was successfully established, compared with control group, model group showed typical manifestation of osteoarthritis, including irregular cartilage surface, osteophyte formation ,joint deformity and cartilage defect, and com- bined with significant decrease of bone density （P〈0.01）, while the decrease was not obvious in proximal tibia （P〈0.05）. After 2 weeks,knee joints in model group was classified as Collins grade 1 and Kellgren-Lawrence grade 2,then classified as Collins grade 4 and Kellgren-Lawrence grade 3 after 4 weeks, control group showed smooth articular surface, normal joint space and intact cartilage surface, knee joints was classified as Collins and Kellgren-Lawrence grade 0, and bone density of distal femur and proximal tibia were normal. Conclusion： Muhispectral animal living imaging technology could be used in dynamic observation of living imaging and detection of bone density in the animal model of osteoarthritis, and it is significant for evaluation of osteoarthritis model, and its reahed tesearch.