摘要
目的初步探讨大鼠脊髓圆锥损伤后膀胱逼尿肌及其神经肌肉接头(neuromuscular junction,NMJ)组织形态学的变化规律。方法成年SD大鼠48只随机分为六组,每组8只。分别为正常对照组,脊髓圆锥损伤术后4、6、8、10及12周组,依次记作A^F组。采用L4、5平面锐性横断性脊髓圆锥损伤的动物模型。分别于术后相应时间点取材,先作膀胱逼尿肌HE染色,以观测肌纤维截面积的变化规律;同时制作电镜标本,观察膀胱逼尿肌及其NMJ超微结构的变化规律;最后将逼尿肌行Masson三色染色,计算平滑肌及结缔组织所占的百分比。结果HE染色观察,大鼠逼尿肌肌纤维截面积在E、F组与A组间差异有统计学意义(P<0.05);透射电镜观察,B^F组逼尿肌细胞外形、大小不一致,分布不均匀,排列走行紊乱;间质中大量排列紊乱的胶原纤维,粗面内质网明显扩张,线粒体水肿,且程度逐渐加重。逼尿肌NMJ透射电镜观察,B、C及D组可见其形态结构类似于A组,但线粒体及突触小泡的数量略少;E组可见明显退变的NMJ,突触小泡含量明显减少,伴有线粒体等细胞器减少;F组NMJ进一步退变,突触小泡含量进一步减少甚至缺如,细胞器减少或消失,并可见退变小体。Masson三色染色可见逼尿肌中结缔组织所占的比例在E、F组与A组间差异有统计学意义(P<0.05);且E、F组间差异亦有统计学意义(P<0.05)。结论大鼠圆锥脊髓损伤术后10周可作为逼尿肌及其NMJ发生变化的时间节点,神经修复手术宜在此前完成。
Objective To investigate the rule of the morphological changes of the detrusor muscle and its neuromuscular junction after the medullary cone injury in rats. Methods Forty-eight SD adult rats were divided into 6 groups randomly, each of which was 8. There were normal control group（group A）, 4 weeks group（group B）, 6 weeks group （group C）, 8 weeks group （group D）, 10 weeks group （group E） and 12 weeks group （group F） after the medullary cone injury respectively. The medullary cone injury was completed in the level of L4.5 with a sharp and transsectional way. The HE dyeing of the detrusor muscle was performed firstly to observe the changes of the section areas of muscle fibers. And the electron microscopic samples of the detrusor muscle were made to investigate the rules of the ultrastructructral changes in the detrusor muscle and its neuromuscular junction. Finally, the Masson trichromatic dyeing of the detrusor muscles was performed to calculate the percentages of the smooth muscle and the connective tissue. Results The HE dyeing of the detrusor muscle indicated the section areas of muscle fibers in groups E, F was significantly less than that in group A （P〈0.05）. The gradually aggravated uhrastructructral changes of detrusor cells in groups B-F were observed in atonic bladders,such as various shape and size,malalignment, wide separation between muscle cells, abundant collagen fibrils and irregular dense structures between individual cells, obvious rough endoplasmic reticulum widen and mitochondrial edema were noted. And the ultrastructructral changes of the neuromuscular junctions manifested that the similar structures in group A and the reduction of the mitochondria and synaptic vesicles was seen in groups B, C and D, the conspicuous degenerative neuromuscular junction and the obvious reduction of the synaptic vesicles and the mitochondria was observed in group E, and the deteriorative degenerative neuromuscular junction and the obvious reduction or disappearance of the synaptic vesicles and the mitochondria even to the degenerative corpuscle was noted in group F. The Masson trichromatic dyeing in the detrusor muscles indicated that there were significant differences in the percentage of the connective tissue in the detrusor muscles between groups E,F and group A, and between group E and group F respectively （P〈0.05）. Conclusion The irreversible changes of the detrusor muscle and its neuromuscular junction can be seen in the 10th week after medullary cone injury in rat. And the nerve repairing procedures should be performed before this.
出处
《中国修复重建外科杂志》
CAS
CSCD
北大核心
2007年第5期473-477,共5页
Chinese Journal of Reparative and Reconstructive Surgery
基金
国家自然科学基金资助项目(30672111)
中国博士后科学基金资助项目(20060390593)
上海市博士后科研资助计划面上项目(06R214102)
第二军医大学博士后科研启动经费资助项目~~
关键词
脊髓圆锥损伤
弛缓性膀胱
逼尿肌
神经肌肉接头
大鼠
Medullary cone injury Atonic bladder Detrusor muscle Neuromuscular junction Rat
