论文部分内容阅读
目的研究Smad4条件基因敲除小鼠前庭终器形态改变,探讨Smad4基因对于前庭发育的作用。方法利用建立的Smad4条件基因敲除小鼠模型,通过光镜观察Smad4(+/+)、Smad4(+/-)与Smad4(-/-)三种基因型小鼠(0.5、1.5月龄)的球囊及囊斑、椭圆囊及囊斑、半规管及壶腹嵴、前庭神经节、内淋巴管与囊的形态结构、毛细胞的形态及排列缺失情况。通过扫描电镜观察球囊斑、椭圆囊斑和壶腹嵴的形态结构、毛细胞及纤毛的排列缺失情况。结果Smad4(-/-)小鼠个体及内耳明显小于Smad4(+/+)和Smad4(+/-),而后面二者区别不大。所有小鼠的球囊及囊斑、椭圆囊及囊斑、半规管、前庭神经节、内淋巴管与囊的大小和结构正常,淋巴囊腔饱满,囊斑处的感觉上皮、耳石、毛细胞及纤毛排列整齐,没有发现明显的病变,三个基因型间没有差异。Smad4(-/-)小鼠壶腹嵴囊性变多且严重、后半规管壶腹嵴出现明显的副嵴、偶尔可见壶腹嵴感觉上皮空泡样变。壶腹嵴的毛细胞和支持细胞排列整齐,形态无明显改变,未见缺失。扫描电镜示球囊斑、椭圆囊斑、后、外、上半规管壶腹嵴正常,三个基因型之间没有差异。结论Smad4(-/-)小鼠的前庭终器有轻微病理改变,Smad4(+/+)与Smad4(+/-)小鼠的前庭终器形态结构基本正常,表明Smad4对于前庭终器的发育影响可能不明显。
Objective To study the morphological changes of the vestibular terminal of Smad4 knockout mice and to explore the role of Smad4 in the vestibular development. Methods Smad4 (+ / +), Smad4 (+/-) and Smad4 (- / -) mice were detected by light microscopy in a mouse model of Smad4 knockout mice (0.5, 1.5 months) Of the balloon and capsule plaques, oval capsule and capsule plaque, semicircular canal and ampulla ridges, vestibular ganglia, lymphatic vessels and the shape of the capsule structure, hair cell morphology and missing arrangement. Scanning electron microscopy was used to observe the morphological changes of balloon plaques, oval capsule plaques and ampulla and the absence of hair cells and cilia. Results The individual and inner ear of Smad4 (- / -) mice were significantly smaller than those of Smad4 (+ / +) and Smad4 (+/-), while the latter two were not significantly different. The size and structure of the balloon and cystoid, oval and cystic plaques, semicircular canal, vestibular ganglia and lymphatic vessels and sacs in all mice were normal, the cysts in the lymphatic sac were full, the sensory epithelium at the plaque, the otolith and the hair cells And cilia arranged neatly, did not find obvious lesions, there is no difference between the three genotypes. Smad4 (- / -) mice ampullary cystic cystic more severe and severe posterior semicircular canal ampulla ridge appeared obvious vice ridge, and occasionally seen ampulla crest epithelial vacuolar degeneration. Ampulla of hair cells and supporting cells arranged in neat rows, no significant change in shape, no missing. Scanning electron microscopy showed balloon plaques, oval capsule spots, after, outside the upper semicircular canal ampulla ridges normal, there is no difference between the three genotypes. Conclusions There is a slight pathological change in the vestibular terminal of Smad4 (- / -) mice. The morphology of the vestibular terminal of Smad4 (+ / +) and Smad4 (+/-) mice is basically normal, indicating that Smad4 plays an important role in the development of vestibular terminals The impact may not be obvious.