河南华溪蟹消化系统的形态结构观察和组织学研究

为研究河南华溪蟹消化系统的形态结构及组织学特征,采用石蜡切片、H.E.染色和光镜等技术,对河南华溪蟹成蟹消化系统各组织器官的结构进行了观察。结果显示,河南华溪蟹的消化系统主要由消化道和消化腺组成。消化道主要包括食道、胃、中肠和后肠,消化腺为肝胰腺。胃包括贲门胃和幽门胃:贲门胃内有钙化的几丁质齿、隆嵴、短刺及刚毛等组成的胃磨,可磨碎食物;幽门胃内侧可见特殊形态的梳状结构,可过滤食物。在光学显微镜下,食道、中肠和后肠均由黏膜层、肌层和结缔组织层构成,其各段内表面均有由上皮细胞与基膜内凸形成的多级皱褶和嵴,有由环形、纵形和辐射状排列的肌层。仅中肠表面有典型微绒毛结构,无角质膜。食道与后肠上皮表面均有较发达的纤毛层。肝胰腺主要由基膜和4种上皮细胞构成,即吸收细胞(R细胞)、泡状细胞(B细胞)、纤维细胞(F细胞)和胚细胞(E细胞)。

Morphological observation and histological studies on the digestive system of Sinopotamon henanense

In this study, morphological and histological observation of digestive system of the freshwater crab Sinopotamon henanense was performed based on paraffin section technique, H.E. staining method and light microscope technique. The results showed that the digestive system comprises of digestive tract and digestive glands. The digestive tract is composed of esophagus, stomach, midgut and hindgut. The digestive gland is hepatopancreas. The stomach of the crab is divided into cardiac stomach and pyloric stomach. There is a gastric mill with calcified teeth, ridges, spines and setae in the cardiac stomach, which is used to grind food. There are several special structures such as combs in the pyloric stomach, which are for food filtration. The results of light microscopy showed that the wall of the digestive tract is surrounded by a layer of cilia, epithelial cells, muscular and connective tissue layers. The ridges in the surface of epithelium mucosa of each segment of the digestive tract wall take the shape of multigrade wrinkles. The muscular layers consist of longitudinal muscle, striated muscle and radiant muscle. Only in the midgut there are typical microvilli. The epithelium of the digestive tract is covered by cuticle except the midgut. There are more developed cilia on the surface of epithelial mucosa of esophagus and hindgut. The hepatopancreas is composed of several ramose hepatic ducts. Each hepatic duct consists of four types of cells: resorptive cells (R cell), blister-like cells (B cell), fibrillar cells (F cell) and embryonic cells (E cell).