大鳞副泥鳅肠呼吸道结构特征研究  

A Study on Structural Characteristics of Intestinal Tract of the Air-Breathing Loach,Paramisgurnus dabryanus (Sauvage,1878)

作　　者：刘亚秋[1] 李新辉[1] LIU Yaqiu;LI Xinhui(Pearl River Fisheries Research Institute,Chinese Academy of Fishery Science,Guangzhou)

机构地区：[1]中国水产科学研究院珠江水产研究所,广东广州510380

出　　处：《珠江水产科学》2018年第4期44-51,共8页Finsheries Science and Technology Industry

基　　金：广东省自然科学基金项目(2016A030313147);公益性行业专项(农业)科研专项(201203086)资助.

摘　　要：利用光镜和电镜对大鳞副泥鳅成鱼肠道的组织形态和超微结构进行观察。其肠道可以分为前、中、后3段,肠壁由内向外包括:粘膜层、粘膜下层、肌肉层和浆膜层。肠道各段的粘膜褶皱高度、粘膜层以及肌层厚度,后肠显著低于前中肠。而较于前中肠,后肠粘膜上皮有大量的毛细血管,这些毛细血管网与肠腔之间的阻隔距离为(1.95±0.34μm)。扫描电镜对肠道粘膜表面观察,后肠无明显褶皱,粘膜表面柱状上皮细胞形状不规则,轮廓不明显,而前中肠表面形成形态复杂的褶皱,并含有大量分泌细胞。粘膜上皮超微察发现,前肠的明显的柱状上皮细胞间连接复合体发达,分布丰富的杯状细胞,胞内含有大量的线粒体和吞饮小泡。与此不同,后肠粘膜上皮细胞上皮细胞为特化的扁平上皮细胞,且与哺乳动物的肺泡Ⅰ和Ⅱ型肺泡细胞超微结构相似,内含有丰富的板层小体。其气血扩散距离主要由3部分组成:超薄的上皮细胞延伸的胞质层(1.47±0.23μm);内皮细胞胞质层(0.21±0.03μm)以及两者之间的基底层(0.27±0.05μm)组成。大鳞副泥鳅肠道兼具消化和呼吸两大功能,前肠为行使消化和吸收功能场所,后肠为进行气体交换辅助呼吸的场所,中肠结构介于前后肠之间,是消化与呼吸重叠的区域。This study aimed to observe morphology and ultrastructure of intestinal tract of P.dabryanus with light and electron mieroscopies.Intestinal tract was divided into three parts.Morphologically complex folds were formed on surfaces of anterior and middle intestines where many secretory cells were present.Highly developed junction complex were seen in anterior intestine.Cytoplasm contained abundant mitochondria and pinocytotic vesicles.Epithelium of posterior intestine was thin,translucent and squamous with dense blood capillary network underground,while there were no folds on mucous membrane surface.Distance between blood capillary network and intestinal cavity was 1.95±0.34 μm.Respiration epithelial cells of posterior intestine are a kind of modified squamous epithelial cells which show the ultrastructural characteristics of both types Ⅰ and Ⅱ pneumocyte of lung alveoli in mammals.The blood is composed of three layers:the thin layer of the extended cytoplasm of respiratory epithelial cells (1.47±0.23μm),the thin sheet of cytoplasm of endothelial cells (0.21±0.03μm)and the basement membrance (0.27±0.05μm)between them is similar to that of the respiratory organs in other vertebrates.Intestinal tract has digestion and respiration functions. Anterior intestine performs digestion/absorption.Posterior intestine performs gas exchange/accessory respiration.In middle intestine,digestion and respiration overlap.

关 键 词：肠道 呼吸 大鳞副泥鳅 显微结构 超微结构 粘膜上皮细胞 

分 类 号：S852.43[农业科学—基础兽医学]