不同年龄大鼠脂肪组织移植后存活率比较研究

The comparison study on the retention rates of adipose tissuses from different ages rats

目的:建立不同年龄大鼠来源的脂肪组织注射移植的动物模型,对比观察研究年龄因素对移植脂肪存活的影响,为临床脂肪移植应用提供依据。方法:取年轻(4周龄)、中年(10月龄)、老年(18月龄)三个年龄组的雌性SD大鼠的皮下脂肪组织,注射移植到同一只SD大鼠(10周龄)的背部皮下,在移植术后24h,48h,72h,96h,5d,7d,14d,4周,8周,分别对脂肪移植物进行超声造影检查,然后取移植物标本,行形态学观察,并制作HE染色、Perilipin免疫荧光染色切片,行组织学观察,比较不同年龄来源的脂肪组织移植后的早期脂肪组织存活情况及远期存活率。结果:SD大鼠的颗粒脂肪组织在移植后出现从缺血退化到再生的动态组织重塑过程,早期仅有移植物最外层的脂肪细胞存活,随后出现血运重建、脂肪细胞再生等组织重塑过程,最终形成正常脂肪组织样结构。4周龄组的脂肪组织在移植后3d内存活脂肪细胞数目,移植后1周时脂肪存活区面积比,血流灌注恢复时间,新生的脂肪细胞数量,移植后8周时移植物存活指数明显优于10月龄、18月龄组(P<0.05);而10月龄与18月龄组间无明显差异(P>0.05)。结论:年轻大鼠的脂肪组织在移植后,脂肪组织的早期存活、血运重建、脂肪细胞再生、远期脂肪组织存活率明显优于中、老年组;而中、老年组的脂肪组织在移植后远期存活率较低,且两者间无明显差异。

Objective To expore the effect of donor age on the retention of fat grafting in rat modle,so as to supply evidence in clinical cases. Methods Fat grafts were obtained from young, middle-aged and aged（4 weeks,10 months, and 18 months old）female SD rats,and then injected into the back of a 10-week-old female SD rat.Ultrasonography and Contrast-enhanced ultrasound exam were taken on each fat grafts at 24h,48h,72h,96h,Sd,1st week,2nd week,4th week and 8th week after operation,to record tissuse reperfusion dynamically,then samples were harvested and analyzed histologically for adipocyte viability,adipocyte regeneration,and fat grafting retention in different groups. Results Fat grafts from all ages underwent dynamic tissue remodeling after grafting,ischemic degeneration at early stage,then regeneration,approaching to normal adipose tissue finally. Fat grafts from 4-week-old SD rats showed signifiantly more vital adipocytes in 72h,larger survival zones at 1st week,and larger engraftment scores at 8th week,more new adipoctyes at 4th week,and more rapid reperfusion rate, respectively,than 10- monthold or 18- monthold SD rats（P〈0.05）.The discrepancy between 10- month- old and 18-month-old SD rats was not significant（P〉0.05）. Conclusion Fat grafts from young rats showed better adipocyte survival, regeneration,and final retention,than middle-aged and aged rats.Final fat grafting retention were similarly low in middle-aged and aged rats.