仿刺参体壁的显微和亚显微结构

Microstructure and ultrastructure of body wall in sea cucumber Apostichopus japonicus

采用光学显微镜和透射电镜对仿刺参体壁的组织结构进行了系统观察。H.E染色结果显示:仿刺参体壁从内向外分为4层——体腔内皮层、肌肉层、结缔组织层和表皮层。体腔内皮层由单层扁平细胞组成;肌肉层为内环外纵排列的平滑肌;结缔组织层由纤维和少量的结缔组织细胞构成;表皮层包括2～3层上皮细胞和其外很薄的角质层。超微结构观察结果显示:平滑肌纤维呈长梭形,无横纹;细胞核一个,呈长椭圆形或杆状,位于中央;细胞骨架主要由密斑、密体和中间丝组成。结缔组织中有大量胶原纤维,弹性纤维较少。细胞类型主要有成纤维细胞和颗粒细胞。表皮层大多为多边形细胞,角质层细胞界限不清,结构不完整,细胞核和细胞器已经完全消失。

Microstructure and ultrastructure of body wall in sea cucumber Apostichopus japonicus were systemically described under a light microscope and transmission electron microscope.H.E staining results show that the body wall consists of coelomic endothelium layer comprising of a simple squamous epithelium,smooth muscular layer with circular muscle inside and longitudinal muscle outside,connective tissue layer and epidermis layer with 2-3 layers of epithelia and a piece of thin cuticle outside.There are fibers and little histiocytes in the connective tissue layer.Ultrastructural observation shows that the smooth muscle fibers are spindle-shaped,non-striated,and have an oval or rod-shaped nuclei in the center.The cellular skeleton is made up of dense patches,dense substances and intermediate filaments.There are striated collagenous fibers and a small quantity of elastic fibers in the connective tissue fibers.The fibroblasts and granulosa are found in the cells in the body walls,including polygonal cells in the epidermis layer.In Keratose layer,unclear boundaries between cells,and completely disappeared nuclei and cytoplasm were observed.