甘肃鼢鼠鼻腔的组织解剖及低氧条件下鼻粘膜内含SP及CGRP的免疫反应纤维

【作者】 王智；

【导师】 李金钢；

【作者基本信息】 陕西师范大学 ， 动物学， 2009， 硕士

【摘要】 甘肃鼢鼠是一种严格营地下生活的啮齿类动物,它所生活的密闭洞道环境使其遭受多重生存压力,低氧即为其中之一。P物质（SP）和降钙素基因相关肽（CGRP）是初级感觉神经元的主要起信号作用的神经肽,低氧条件下肽能神经纤维内SP及CGRP含量的变化情况反映了动物体对所遭受的有害刺激的感觉适应情况。本文运用组织学方法对甘肃鼢鼠的鼻腔进行了解剖学研究,分析了其鼻腔结构与其它啮齿动物的差异,应用免疫组织化学方法对比了常氧条件下与低氧条件下（10.5%O₂每天8小时,持续一个月）甘肃鼢鼠鼻腔粘膜的SP及CGRP能神经纤维平均长度的变化情况,探究甘肃鼢鼠上呼吸道对其所生存的低氧环境的适应。通过研究得出以下主要结论:1.甘肃鼢鼠的鼻腔粘膜与其它啮齿动物一样,分为前庭粘膜、呼吸粘膜和嗅粘膜,粘膜的上皮细胞类型也分为扁平上皮、变移上皮、呼吸上皮和嗅上皮四种类型,粘膜从外到里依次为上皮、基层和固有层。甘肃鼢鼠鼻腔中嗅粘膜所占比例较大,几乎覆盖了上颌鼻甲的大部分和鼻中隔的一半多,这与其发达的嗅觉功能是相适应的。由于呼吸粘膜中杯状细胞所分泌的粘蛋白能保护上皮免受细菌、病毒侵害,故构成免疫的第一道防线,但甘肃鼢鼠呼吸粘膜中杯状细胞很少,几难见到,这与其在实验室饲养环境中免疫功能低下的事实是一致的,所以推测杯状细胞的缺失可能是甘肃鼢鼠免疫功能低下的一个原因。2.甘肃鼢鼠在低氧条件下鼻腔粘膜的SP及CGRP免疫反应神经纤维的平均长度虽然较之常氧条件有所增加（p＜0.05）,但未达到极显著水平,另外,甘肃鼢鼠鼻腔粘膜内肽能神经增加率（相对于常氧条件）明显小于SD大鼠而与常氧条件下相差不大（低氧条件下肽能神经平均长度与常氧条件的比率小于1.5）,这说明低氧环境并未对甘肃鼢鼠的上呼吸道造成较大影响,对甘肃鼢鼠还算不上严重的有害刺激,所以推断,甘肃鼢鼠的上呼吸道对低氧环境的不敏感性是对其极端生存环境的一种适应性特征。但目前还没有做低氧条件下甘肃鼢鼠的气管、肺等器官的粘膜内肽能神经纤维相对于常氧条件的变化研究,因此,甘肃鼢鼠呼吸道对低氧环境的适应还有待于进一步研究。更多还原

【Abstract】 Myospalax cansus is a subterranean rodents. It has to be faced with multiple pressures of survival due to living in the confined tunnel environment,and hypoxia is one of the pressures. Substance P （SP） and calcitonin gene-related peptide（CGRP） in primary sensory neurons are predominant signal substances to transmite sensory information. The change of SP and CGRP content within peptidergic nerve fibers in hypoxic condition shows how Myospalax cansus adapts to the harmful stimulus.In this paper, the nasal cavity of Myospalax cansus were studied by using histology and anatomical approach. We revealed the differences between Myospalax cansus and other rodents in the nasal cavity. Using immunohistochemical technique,the distributing density of SP-immunoreactive and CGRP-immunoreactive nerve fibers in the nasal mucosa was compared between normoxic and chronically hypoxic Myospalax cansus （10.5%O₂ for 8 hours everyday within 1 month） . We tried to find how Myospalax cansus adapts to hypoxic condition in the upper respiratory tract and drew the following conclusions:1. Be similar to other rodents, the nasal mucosa of Myospalax cansus is divided into the vestibular mucosa, respiratory mucosa and olfactory mucosa, and the epithelial cell type of the nasal mucous is also divided into squamous epithelium, transitonal epithelium ,respiratory epithelium and olfactory epithelium. From the outside to inside of the nasal mucous ,the epithelium is followed by basal lamina and lamina propria. The olfactory mucosa accouts for a large proportion of the nasal mucosa.It almost covers the majority of maxilloturbinate and half of the nasal septum, which features was adapted to well-developed sense of smell of Myospalax cansus. The goblet cell in respiratory mucosa can protect the epithelium from bacteria, viruses as result of secreting mucin, and it constitutes the first line of defense. But the goblet cells of respiratory mucosa in Myospalax cansus are few, which may be one of the reasons why the immunity of Myospalax cansus with reared in the laboratory is compromised.2. In nasal mucosa in hypoxic Myospalax cansus , the relative density of SP- and CGRP-immunoreactive nerve fibers was also higher than normoxic mucosa（p<0.05）, but that did not reach very significant levels, In addition, in hypoxic Myospalax cansus nasal mucosa, the rate of increase of peptidergic nerves （be compared with Myospalax cansus in normoxic conditions） was significantly smaller than the SD rats, and has little difference between normxic and hypoixic conditions （the ratio of them was less than 1.5）. It suggests that hypoxic environment has no greater impact on upper respiratory tract of Myospalax cansus. Thus, we thinked that the upper respiratory tract in Myospalax cansus was no highly sensitive to hypoxic entironment , which adated to the extremely living environment. However, in hypoxic trachea mucosa, lung mucosa ,the density change of peptidergic nerve fibers have been not studied. The hypoxic adptation in whole respiratory tract in Myospalax cansus has still been further researched.更多还原