【作者】 郑月茂； 徐永平； 卿素珠； 蒲鹏； 张涌；

【Author】 ZHENG Yue-mao, XU Yong-ping, QING Shu-zhu, PU Peng, ZHANG Yong(Biology Engineering Research Center, Northwest Sci-Tech University of Agriculture and Forestry,Yangling, Shaanxi 712100, China)

【机构】 西北农林科技大学生物工程研究所；

【摘要】 对3-22周龄山羊胎儿肺进行了光镜观察,结果表明:山羊胎期肺的发育分为5个时期:(1)胚胎期(3-5周)肺芽分支形成主支气管,主支气管长度不断增长并萌芽出叶支气管,均衬以假复层柱状上皮。(2)腺状期(6-12周)以支气管树发育为主,小支气管衬以假复层和/或单层柱状上皮;终蕾呈腺状, 上皮细胞由假复层柱状逐渐变为单层柱状,胞核向细胞顶端移行。(3)小管期(13-14周)以呼吸部发育为主,原始肺泡开始形成,呼吸性细支气管衬以未分化的立方上皮;终蕾腺状结构逐渐消失,终蕾上皮细胞由高矮不等的单层柱状上皮逐渐演变为立方形的原始肺泡上皮。(4)囊状期(第15周)呼吸部发育显著,肺内细支气管及其末端呈现出“充气”状态;部分原始肺泡上皮细胞分化为扁平的肺泡Ⅰ型细胞和立方形的肺泡Ⅱ型细胞。更多还原

【Abstract】 Lungs of prenatal goats (3-22 wks) were observed with LM, the results are as following: The lungs of prenatal goat have five stages during their development: (1) Embryologic stage(3-5wks) : The lung bud branching and forming into the two principal bronchi, The principal bronchi increase in length and budding lobar bronchi lined with pseudostratified columnar epithelium. (2)Pseudoglandular stage(6-12wks): The bronchial divisions were differentiated and their air conducting system became established, lined with pseudostratified and/or single-walled columnar epithelium. The terminal bud assumes a glandular aspect. The terminal bud epithelium were differentiated from pseudostratified columnar epithelium into single-walled columnar epithelium. The nuclei transfer to the top of the epithelial cells gradually. (3) Canalicular stage (13-14wks): The respiratory bronchioles developed quickly, the primitive alveoli had developed, the respiratory bronchioles were lined by cuboid cells. The terminal buds’ glandular structures disappeared gradually, the respiratory bronchioles and primitive alveoli epithelium were differentiated from single-walled columnar epithelium into cuboid epithelium. (4) Saccular stage (15wk): The respiratory divisions developed dramatically, The lung assumes a more "aerated" appearance, i.e. the prospective air space volume increases relate to the tissue components. Parts of the primitive alveoli epithelium differentiated into flattened type Ⅰ alveolar cells and cuboid type Ⅱ alveolar cells. (5) Alveolar stage (16-22wks): The alveoli developed dramatically, more alveoli epithelium differentiated into flattened (type Ⅰ cell)and cuboid (type Ⅱ cell)epithelial cells .During this stage, the capillary endothelium were pressed close to some of the alveolar epithelium.更多还原