大鼠胚胎肺泡发育形态学观察研究

Morphological research of lung development in fetal rat

目的:观察大鼠胚胎肺泡发育形态学变化,建立连续系统的胎肺发育形态学资料。方法:自SD大鼠孕16 d起,分别取孕16、19、21 d胎鼠肺脏行HE切片染色及透射电镜观察。结果:胚胎16 d胎肺开始出现上皮性管道,形成支气管众多分支,上皮细胞呈高柱状,围绕排列成环形;在胚胎19 d肺泡腔逐渐扩大,出现板层小体和2型肺泡上皮细胞;在胚胎21 d肺泡分隔增多,腔体扩张,间质变薄,同时板层小体数目增多。结论:大鼠胎肺发育是循序渐进的过程,一直延续到生后。板层小体的出现是肺泡2型上皮细胞分化的标志,且其数目随着发育而增多。

Objective： To study morphological evolution of fetal lung in SD rats and establish continuous systematic morphological datum.Methods： Fetal lungs at embryonic day16（E16）,E19,E21,were taken out respectively,and were observed by HE staining under light microscope and electric microscope.Results： At E16,epithelial tract began to appear,which was constructed by tall epithelium,and developed many airway branches.At E19,alveolar space extended gradually,then lamellar body and type-II pneumonocytes began to emerge.At E21,alveolar separation increased gradually,and mesenchyma turned into thiner than before.At the same time the number of lamellar body increased gradually.Conclusion： The fetal lung development is a gradual process.In fact,this process will continue to postnatal stage.The appearance of lamellar body is the sign of differentiation of type-II pneumonocytes,and it increases along with lung development.