人胎后期大肠NOS阳性神经元发育的免疫组化观察

目的探讨人胎发育后期大肠壁内NOS阳性神经元的生长发育规律。方法用免疫组织化学法显示NOS阳性神经元并进行观察、分析。结果第8~10个月龄时,肌间神经丛内NOS阳性神经元胞体呈圆形或椭圆形,大小不一,染色深浅不同。胞体大的神经元,胞质丰富,染色深;胞体小的神经元,胞质少,染色淡。内环肌层有散在分布的NOS阳性神经元。有的神经元突起与内环肌肌纤维之间的膨体纤维紧密接触。内环肌层膨体纤维分布较密。粘膜下层结缔组织内NOS阳性神经元分布稀疏,胞体大,染色深,并发出大量神经纤维伸入其周围的结缔组织。粘膜固有层中可见到NOS阳性神经元分布,粘膜肌内也有NOS阳性神经纤维表达。结论在人胎后期,大肠壁内NOS阳性神经元逐渐发育成熟,并与各层组织细胞的发育有密切关系。

Immunohistochemical detection of large intestine in human fetus for the development of nitric oxide synthase positive neurons

Objective To explore the rule of the development of NOS positive neurons within the wall of the large intestine in human fetus during the eighth to tenth month of gestation. Methods The expression of NOS positive neurons in the large intestine of human fetus, in the final stage of the growth and development, was observed by using immunohistochemical method. Results At the eighth to tenth month of gestation, NOS positive neurons presented round or oval in intermusculer nerve plexus. The cell bodies of NOS positive neurons were found different in sizes and dyeing. The bigger cell bodies of NOS positive neurons were filled with abundant cy- toplasm and dense dyeing, but the smaller ones of NOS positive neurons were reverse. There was a small quantity of NOS positive neurons thinly distributed in the inner circular muscle layer, which were similar to the bigger cell bodies of NOS positive neurons distributed in the intermuscular nerve plexus. The varicose fibers were densely contacted with the processes of some NOS positive neurons in the inner circular muscle layer. A small quantity of NOS positive neurons was thinly distributed in the connective tissue of the submucoa and their cell bodies were seen bigger and dyeing was denser,with a great deal of nerve fibers thrown out from that to the connective tissue of the submucoa. NOS positive neurons were seen in the lamina propria of the large intestinal mucosa, and some NOS positive nerve fibers were seen in the mucosal muscles as well. Conclusion This finding suggests that NOS positive neurons grow up towards the final stage and they are closely connected with the cells and tissues in the different layers within the wall of the large intestine.