人胎儿腓肠神经的显微与超微结构研究  

MICRO-AND ULTRASTRUCTURAL STUDIES ON SURAL NERVE IN HUMAN FETUS

作　　者：卢戈[1] 

机构地区：[1]兰州医学院组织学胚胎学教研室,兰州730000

出　　处：《动物学报》1994年第1期12-18,共7页ACTA ZOOLOGICA SINICA

基　　金：甘肃省卫生厅资助;甘卫科教字(88)第106号。

摘　　要：光镜与电镜下研究了２２例人４－足月胎儿腓肠神经，发现：４月龄是形成髓鞘的开始阶段；７月时其数量与足月相近。４月时血－神经屏障已趋完善，血管中见有核红细胞；５月后再未见。４月龄神经束膜完善，可达１６—２０层。４月１０天见肥大细胞存在，即分化在此之前，但颗粒还不成熟、４－足月标本均见轴突和髓鞘变性；亦见无髓纤维中囊泡聚积。The sural nerves of 22 human fetuses aging from 4 months to full term were studied by means of light and electron-microscopy. It was found that: 1. Development of mylin sheath:Mylinated fibers started to occur in fetuses of 4 months and 10 to 20 days age ; then,more myelinated fibers increased,until the fetus was 7-months old,the number of the former approximated that of the mature fetus ; 2. Development of vessels:They were well developed in the 4-month old fetus. The tight' junction between the endothelial cells and the basement lamina of ti.p endothelium 4f the en doneurial capillaries were well developed band the perivascular cells occurred, TheSe suggested that the blood-nerve barrier was already perfected or towards perfection. The endothelial basement lamina of the epineurial arteriole well developed. The small young lymphocytes and sometimes the nucleated red blood cells were frequently seen 'within the.e vessels. After' the sib month,no nucleated red blood cell was seen. And after the 7th month,the postcapillary venules with the cuboidal endothelial cells could be demonstrated I 3. Perineurium: It was also more perfectly developed. In the 4th month,some perineurium consisted of 16- 20 layers of perineurial cell. The occurence of tight,gap junctions and desmosomes between the perineurial cells was similar to those of the mature. There was more embryonic mucous substance surrounding the perineurial cells. The perineurial canaliculi were seen. 4. Mast cells:The mast cells existed between the perineurial cells in a fetus of 4 months and 10 days old age,this suggested that the differentiation' of mast cells started before this time. But until birth,the granules of the mast cells were not yet fully azure; 5. Degeneration of myelin sheath and axon and the aggregation of vesicles; The degenaration could be seen in all the stages from the 4th month to full, term,this suggested that the death of the neurons and schwann cells occurred in all the developing stage of human fetus. The accumulation of vesicles within

关 键 词：胎儿 周围神经 显微结构 超微结构 

分 类 号：R329.1[医药卫生—人体解剖和组织胚胎学]