中华鳖胃的显微和亚显微结构

Microscopic and submicroscopic structure of the stomach of Trionyx sinensis

中华鳖的胃壁由粘膜层、粘膜下层、肌层和浆膜组成。肌层较厚 ,环形肌特别发达。胃腺为单管状或分支管状腺。仅由壁细胞和粘液细胞组成。壁细胞数量很多 ,在贲门腺和幽门腺也有大量分布 ,壁细胞的亚显微结构特征是 :有明显的细胞内小管 ;滑面内质网十分发达 ,有许多微管泡系 ;细胞的侧面还见到细胞间小管 ;线粒体、高尔基复合体、粗面内质网也十分丰富 ,而且胞质中有许多大而圆的分泌颗粒。经电镜结合 Cl-定位和 ACP酶定位 ,证明中华鳖壁细胞具有分泌盐酸和胃蛋白酶原的双重功能 ;其胞质中的分泌颗粒即酶原颗粒。因此 ,中华鳖的壁细胞可称为壁 -主细胞。

It was found that the stomach wall of Trionyx sinensis consisted of mucoua ,submucoua, muscularis and serosa. Muscularis was comparatively thick and circular muscle was especially developed. Cardiac glands ,fundic glands and pyloric glands were all simple tubular glands or branched tubular glands . Gastric glands consisted of two types of cells only,and they are parietal cell and mucous cell. Parietal cells had a large quantities and distributes in the cardiac glands and pyloric glands too.The submicroscopic structural characteristics of parietal cells of Trionyx sinensis were:apparent intracellular canaliculi, very developed smooth endoplasmic reticulum and many microtubulovesicular system . Further more ,intercellular canaliculi could be seen in the cell lateral ;Comparatively developed mitochondria ,Golgi complex and rough endoplasmic reticulum could be seen near the nucleus . There are many big and round secretory granules in the cytoplasm. By using electron microscope as well as localization of Cl - and ACP enzyme activities,it was confirmed that parietal cells of Trionyx sinensis have double functions of secreting hydrochloric acid and pepsinogen; Secretory granules in the cytoplasm were zymogenic granules right.Therefore ,parietal cells of Trionyx sinensis could be called parietalpeptic cells.