不同月龄大鼠椎间盘纤维环退行性变与血管内皮生长因子表达的关系

Degeneration of annulus fibrosus of intervertebral disc associated with the expression of vascular endothelial growth factor in rats at the age of different months

目的:观察大鼠不同月龄椎间盘纤维环的形态学变化并检测其中血管内皮生长因子的表达,探讨血管内皮生长因子与椎间盘纤维环退行性变的关系。方法:实验于2004-12/2005-01在中国医科大学基础医学院组织工程第三实验室完成。取Wistar大鼠50只,以大鼠1,3,6,12,18个月龄不同分为5组。采用免疫组织化学方法观察椎间盘纤维环中血管内皮生长因子的表达情况,并测定部分视野的平均吸光度值,以平均吸光度值的高与低显示血管内皮生长因子表达的强与弱;采用苏木精-伊红染色观察软骨细胞、成纤维细胞及胶原纤维的形态学变化。结果:进入结果分析实验大鼠50只。①随着大鼠月龄的增长,其椎间盘纤维环中血管内皮生长因子的表达发生变化,低月龄组(1,3个月龄)血管内皮生长因子表达强烈(平均吸光度值41.70±11.19,36.42±11.98),成龄组(12个月龄)表达较弱(平均吸光度值6.67±4.44),两组差异意义显著(P<0.01)。②大鼠椎间盘纤维环的组织结构也随大鼠月龄增长发生变化,软骨细胞数量减少,胶原纤维增生、粗大,走行紊乱。结论:大鼠椎间盘纤维环结构随月龄增长发生退行性变,纤维环中血管内皮生长因子表达强烈,则纤维环退行性变进程快,对椎间盘退行性变有不良影响。

AIM:To investigate the morphological changes of anulus fibrosus of interverte bral disc and the expression of vascular endothelial growth factor(VEGF) in the anulus fibrosus of rats at different months,so as to probe into the association of VEGF with degeneration of annulus fibrosus. METHODS:The experiment was conducted in the Third Laboratory for Tissue Engin eering,College of Basic Medical Sciences,China Medical University from December 2004 to January 2005.Fifty Wistar rats were divided into 5 groups according to t heir different months:1- month,3- month,6- month,12- month and 18- month gr oups.The expression of VEGF in annulus fibrosus of intervertebral disc was obser ved by immunohistochemistry,and mean absorbance(A) under some sights was assayed .The higher and lower mean A value described the higher and lower VEGF expressio n.The histological changes of chondrocytes,fibroblasts and collagen fibers were observed by hematoxylin and eosin(HE) staining. RESULTS:All the 50 rats were included in the result analysis.① The expressio n of VEGF in annulus fibrosus significantly varied as the rat aging,and that in the 1- month and 3- month groups(the mean A value was 41.70± 11.19 and 36.42 ± 11.98 respectively) was significantly higher than that in the 12- month grou p(the mean A value was 6.67± 4.44)(P< 0.01).② Histological structure of annulu s fibrosus in the rat intervertebral disc also changed along with the rat aging. The quantity of chondrocytes decreased and collagen were thick,hyperplastic and disorganized. CONCLUSION:The annulus fibrosus of rat intervertebral disc degenerates along with their ages of months.The high expression of VEGF results in the progressing degeneration of annulus fibrosus and has adverse effects on the degeneration of intervertebral disc.