日本鳗鲡胃肠胰内分泌细胞的鉴别与定位

Location and identification of endocrine cells in the gastro-entero-pancreas of Anguilla japonicus

应用过氧化物酶标记的链霉亲和素(streptavidin-peroxidase简称S-P法)免疫组织化学技术,用抗5-羟色胺、生长抑素、胃泌素、β-内啡肽、胰高血糖素抗体对日本鳗鲡的胃肠胰内分泌细胞进行研究。结果表明:日本鳗鲡胃肠道各段均存在5-HT和Som免疫活性内分泌细胞。Gas细胞分布于胃体部、幽门部和前肠、中肠;胃贲门部和后肠未检出Gas细胞。β-内啡肽、Glu细胞在胃肠道各段均未检出。在胰腺中均鉴别出Glu细胞和Som细胞。

With immunohistochemistry method, the endocrine cells in the gastro-entero -pancreas of eels, Anguilla japonicus were located and identified. Using 5-hydroxytryptamine(5-HT), somatostation (Som), gastrin(Gas), β-endorphine(END) and glucagon(Glu) antisera, the endocrine cells in the gastro-entero -pancreas of the eel, A. japonicus were studied with an immunohistochemical technique of streptavidin labelled peroxidase. The weight of eels, coming from aquafarm, Fuqing, Fujian Province of China, was about 400g. The tissue section of the cardia, gastric fundus, pylorus, foregut, midgut, hindgut and pancreatic gland of the four eels were prepared. The concentrations of the antiserum of Glu, Gas, Som, 5-HT and END were 1:50, 1:1000, 1:100, 1:50 and 1:500 respectively. The major staining process was as follows:1. to deparaffinize and rehydrate tissue section, and wash 2 times in buffer; 2. to reduce nonspecific background staining due to endogenous peroxidase, incubate the slide in 3% hydrogen peroxide block for. 10-15 minutes, and wash 4 times in buffer; 3. to block nonspecific background staining, incubate for 10 minutes in buffers containing 10% normal goat serum at room temperature; 4. to apply primary antibody and incubate for one night at 4℃; 5. to incubate with biotin anti-mouse/rabbit IgG for 10 min at 37℃; 6. to incubate with streptavidin-peroxidase for 10 min at 37β; 7.to incubate with DAB for 10 min at room temperature. The result showed that there is distribution-of 5-HT and Som immune active endocrine cells in every part of digestive tract. Gas cells are distributed in the gastric fundus, pylorus, foregut and midgut, and not found in cardia as well as hindgut. β-endorphine and Glu cells were not found in every part of digestive tract either. But Glu and Som cells were identified in the pancreatic glands. The densities of 5-HT, Som and Gas cells in the pylorus were highest. The shapes of 5-HT, Som and Gas cells were shuttle, triangle shape etc in the mucous epithelium of the digestive tract of the eels, there were longer cellular protuberace in the cells which could reach gastro-entero antrum and the cells were opening type cells. There were a small number of the cells of 5-HT, Som and Gas in the lamina propria of gastro-entero tract, there was no cellular protuberace in the cells and the cells were occlude type cells. In this paper, the morphologic characteristics of endocrine cells of gastro-entero -pancreatic system in A. japonicus are described and their distribution feature is discussed.