长鳍篮子鱼消化道显微与超微结构观察

Microstructure and ultrastructure observation of the digestive tract of Siganus canaliculatus

采用光镜和电镜技术观察了长鳍篮子鱼消化道的组织结构。结果表明,食道黏膜上皮为复层扁平上皮,表层扁平细胞下有黏液细胞,黏膜下层含有大量腺体。胃黏膜上皮为单层柱状,胃贲门、盲囊部分布有许多腺体,幽门部较少;胃柱状细胞中有较多的线粒体、粗面内质网和高尔基体,在一些细胞中含有大量的吞饮泡。肠道黏膜上皮为单层柱状上皮,其中含有许多杯状细胞;肠上皮细胞游离面有密集的微绒毛,侧面有连接复合体,胞内细胞器较丰富,在细胞上部分布有大量多泡体。由前肠到后肠,黏膜褶皱高度由高变低,数量逐渐减少,肌层逐渐变厚,后肠分布有大量淋巴细胞,紧密排列成环状。幽门盲囊组织构造与肠道相似,但上皮细胞游离面有比肠道更密集的微绒毛。长鳍篮子鱼消化道组织结构的特点与其消化、吸收作用密切相关。

The histological structure of the digestive tract of Siganus canaliculatus was studied by using light and electronic microscopy. The esophagus mucosa was composed of stratified squamous epithelium with many mucous cells and there were lots of glands in the submucosa. The stomach mucosa formed with a single-layered columnar epithelium. The gastric cardiacus and caecum contained many glands while the gastric pyloricus contained less. The gastric columnar cells included more mitochondrion, rough endoplasmic reticulum and Golgi apparatus, some of cells had many pinosomes. The intestine epithelium was also single-layered columnar epithelium, including a great number of goblet cells. Dense microvilli were observed on the free surface of the epithelium, junctional complex was present on its lateral edge and, abundant cell organs were present in its cells. There were a lot of multivesicular bodieson at the top of the epithelium cell of the intestine. With changes from foregut to hindgut, the height of folds decreased and the number of folds was reduced gradually, in addition, the muscular coat became much thicker. Large numbers of lymphocytes were distributed in the hindgut, which closely arranged in ring. The histological character of the pyloric caeca was similar to the intestine＇ s, but the epithelium cell of the pyloric caeca had denser multivesicular than the intestine＇ s. The results showed that there was close correlation between the characteristics of histology structure in digestive tract and digestion and absorption of S. canaliculatus.