神经原性膀胱逼尿肌超微结构的变化

目的　了解低反射神经原性膀胱患者逼尿肌超微结构的改变。　方法　膀胱顶部逼尿肌分别取自 11例神经原性膀胱手术患者和 7例意外死亡新鲜尸体膀胱 ,透射电镜观察两组逼尿肌超微结构差异。　结果　低反射神经原性膀胱逼尿肌有去极化现象 ,超微结构改变包括肌细胞外形不一致、分布不均匀 ,走行紊乱 ;细胞中间连接少 ,常填充以胶原纤维和无定形成分 ;肌质膜下胞饮小泡减少 ;细胞内线粒体减少 ,肌丝走行紊乱 ,致密体分布不均等。正常平滑肌细胞外形、大小基本相似 ,分布均匀 ,走行整齐一致。细胞中间连接多 ,细胞间距小、均匀 ;胞饮小泡与密区沿肌质膜均匀分布 ;细胞内见各种细胞器 ,肌丝及致密体平行整齐排列。　结论　低反射神经原性膀胱逼尿肌超微结构改变可能和逼尿肌去神经性无力 ,逼尿肌尿道括约肌原有平衡失调 ,造成膀胱出口相对阻力增加等有关。神经原性膀胱患者临床上宜及早采取预防措施 ,防止继发性逼尿肌超微结构改变对其收缩能力的进一步影响

Ultrastructural observations on detrusor musculature in areflexia neurogenic bladders

Objective To understand the ultrastructure of detrusor musculature in areflexia neurogenic bladders. Methods The detrusor secured from the anterior wall of bladders was studied and compared by means of transmission electron microscope in 11 patients with areflexia neurogenic bladder during cystomyoplasty with musculus rectus abdominis and in 7 accidentally deceased young men in autopsy. Results Ultrastructural changes of de differentiation of detrusor cells were observed in areflexia neurogenic bladders,such as inconsistent contours,malalignment and disarray.Wide separation between muscle cells with reduction of intermediate cell junction and with abundant collagen fibrils and irregular dense structures between individual cells were noted.There were also such changes as reduction of pinocytotic vesicle and mitochondria,disarray of myofilaments and malalignment of dense body,etc.,in detrusor cells.By contrast normal detrusor cells were well arranged and well distributed with consistent contours and size.The distance between muscle cells was much smaller than the abnormal specimens with proper intermediate junction.Caveolae and dense area were evenly distributed among the sarcoplasm.Organelles,myofilament and dense body were well organized in the smooth muscle cells. Conclusions The ultrastructural changes of detrusor in areflexia neurogenic bladders may be associated with relative increment of bladder outlet obstruction,which is probably due to detrusor debility from diseased nerve and sequential disequilibrium between normal detrusor and sphincter muscle of the urethra.Prophylactic management of lower intra bladder pressure may be beneficial to the prevention of ultrastructural deterioration in detrusor cells.