不同胎龄脊髓脊膜膨出胎鼠膀胱和脊髓神经损害的形态学观察  

Morphological observation of nervous lesion of spinal cord and bladder in fetal rats with meningomyeloceleat various gestational ages

作　　者：沈剑[1] 单丸九[1] 周国民[2] 陈宏[1] 

机构地区：[1]复旦大学附属儿科医院,上海 201102 [2]复旦大学上海医学院组织胚胎与解剖学系

出　　处：《中华小儿外科杂志》2012年第6期458-463,共6页Chinese Journal of Pediatric Surgery

摘　　要：目的通过不同胚胎期脊髓脊膜膨出（MMC）胎鼠膀胱平滑肌的发育和神经支配情况及脊髓神经损害的形态学观察，了解这种损害的时间和空间上的变化及其相互关系。方法胎鼠分为MMC组和正常对照组，每组再根据胎龄各分3小组，共6小组。用免疫组织化学法检测各组腰骶段脊髓GFAP、VAChT的表达和膀胱”Actin和neurotubulin-β-Ⅲ的表达；另取各组腰骶段脊髓及膀胱切片作HE染色。Image-Pro Plus5．1软件分析免疫组织化学照片相关部分的光密度，SPSS16．0软件对数据进行进行统计分析，以P≤0．05为差异有统计学意义。结果在胚胎16d，2组胎鼠的膀胱肌层内就已经可以检测出neurotubulin-β-Ⅲ的表达；胚胎16、18和20d时，MMC组胎鼠膀胱内的neurotubulin-β-Ⅲ表达较相同胚胎期的正常对照组显著降低。在胚胎16、18、20d，2组的膀胱肌层内都能看到较多的旷Actin的阳性显色；且各胚胎期，2组膀胱内的mActin表达差异无统计学意义。在胚胎16d和18d，正常组和MMC组及胚胎20d正常组的脊髓内，GFAP染色均很少，没有明显的星形胶质细胞显示，在胚胎20d的MMC组胎鼠的脊髓背侧，可见大量的GFAP阳性的星形胶质细胞显影，其表达显著高于正常组。MMC组各个胚胎期脊髓VAChT的表达都较少，在胚胎20d组的背外侧核仅见少量阳性表达的神经元；而正常组VAChT的表达相对较多，在胚胎20d组的背外侧核可见较多阳性表达的神经元；2组间各胚胎期VAChT表达差异均有统计学意义。结论MMC胎鼠膀胱平滑肌的分化和发育与正常组差别无统计学意义。MMC胎鼠胚胎16d，膀胱肌层内可见神经支配，但神经纤维减少，与脊髓内骶副交感神经核和背外侧核的胆碱能神经元减少是同步。MMC胎鼠脊髓损伤后的神经修复过程，星形胶质细胞的出现要晚于胚胎18d。Objective The development and distribution of bladder smooth muscle and morphol- ogy of nervous lesion in spinal cord of MMC fetus at various gestational ages were observed, aiming to reveal the interaction between lesion of spinal cord and bladder tissue. Methods Fetus was divided in- to MMC group and control group. Each group was further divided into three sub-groups at disparate fetal age： E16, El8 and E20. The α-actin and neurotubulin-β-Ⅲ were analyzed in bladders; the ex- pression of GFAP and VAChT were analyzed in lumbosacral levels spinal cords by immunohistochem istry assay. Photos were taken to determine the integrated optical density of each sample. Data were analyzed by independent t-test using SPSS 16. 0 software. Statistical significance was defined as P≤ 0. 05. Results Neurotubulin-β-Ⅲ in MMC group was significantly lower than that in control group at all fetal age. Numerous of α-actin was detected in both groups at all fetal age. No significant difference was found between them. At E16 and El8, no powerful GFAP positive signals in both groups were found. However at E20, on the dorsal region of spinal cord, numerous GFAP positive signals were seen, which presented significant difference in contrast to control group. Regarding to the VAChT, the signals detected in MMC group were weaker than that in control group at all fetal age, and signifi- cant difference could be noted. At E20, a number of VAChT positive neurons were observed in dorso- lateral nucleus in control group. Conclusions In term of morphology, the differentiation and develop ment of bladder smooth muscle in MMC fetal rats is as good as normal fetus. Innervation to bladder smooth muscle in them occurred after E16, and the degeneration of innervation to the bladder in MMCfetus has occurred in this time. This change is synchronously with the reduction of cholinergic neuron in sacral parasympathetic nucleus and dorsolateral nucleus of the spinal cord. Numerous of astrocytes emerge in dorsal region of spinal cord in MMC fetus at

关 键 词：膀胱 神经原性 脊髓脊膜膨出 胚胎 维甲酸 

分 类 号：R714.5[医药卫生—妇产科学]