牛蛙胃肠胰系统内分泌细胞的免疫组织化学鉴定与定位

应用过氧化物酶标记的链霉卵白素(S-P)免疫组织化学方法对牛蛙(Rana catesbeiana)胃肠胰系统5种内分泌细胞进行了鉴定与定位.在消化道中检测到了5-羟色胺(5-HT)、生长抑素(SS)、胃泌素(Gas)和胰高血糖素(Glu)细胞.5-HT细胞主要分布于胃幽门部和空肠,食道中偶见.SS细胞主要分布于胃,幽门部较密集,小肠各段少量,直肠和食道偶见.Gas细胞主要分布于小肠各段,胃和直肠中偶见,食道中未检测到.Glu细胞主要分布于胃和直肠,小肠各段偶见,食道中未检测到.在胰腺中检测出了5-HT、SS、Gas、Glu和胰多肽(PP)细胞.SS、Glu和PP细胞数量较多,成簇分布于胰岛中,5-HT和Gas细胞少量,散在分布于胰腺腺泡之间.胃腺部和胰腺内分泌细胞多呈圆形、椭圆形或形态不规则,有的可见明显胞突伸向邻近细胞,胃肠道上皮中的内分泌细胞多呈梭形、楔形或锥形,有的可见明显胞突伸向消化腔.与其它两栖动物相比,牛蛙胃肠胰系统内分泌细胞的存在与分布有一些共性,也存在着种间差异.

Immunohistochemical Identification and Localization of Endocrine Cells in the Gastro-entero-pancreatic System of Bullfrog Rana catesbeiana

Identification and localization of five types of endocrine cells in the gastro-entero-pancreatic system of Bullfrog Rana catesbeiana were studied with Streptavidin peroxidase(S-P) immunohistochemical method.Four types of endocrine cells were detected in the digestive tract of R. catesbeiana, they were 5-hydroxytryptamine (5-HT), somatostatin (SS), gastrin (Gas) and glucagon (Glu) cells. 5-HT cells were observed throughout the digestive tract, mainly distributed in the stomachus pyloricus and jejunum, occasionally seen in the esophagus. SS cells were mainly distributed in the stomach with the highest density in the stomachus pyloricus, rarely found in the small intestine and occasionally occurred in the rectum and esophagus. Gas cells were mainly presented in the small intestine, and occasionally occurred in the stomach and rectum, not detected in the esophagus. Glu cells were mainly detected in the stomach and rectum, occasionally found in the small intestine, not detected in the esophagus. Five types of endocrine cells were detected in the pancreas of R. catesbeiana, namely 5-HT, SS, Gas, Glu and pancreatic polypeptide (PP) cells. SS, Glu and PP cells were mainly distributed collectively in the pancreas islet with large quantity, while 5-HT and Gas cells located scatteredly in the pancreas alveoli with small quantity. Endocrine cells in the gastric glands and pancreas were mainly round, oval or irregular in shape, some cell had a long cytoplasmic process extending to its adjacent cells. Endocrine cells in the gastrointestinal epithelium were mainly fusiform, cuneiform or conical, some cell had a long cytoplasmic process reaching into the digestive lumen. The regional distribution and relative frequency of endocrine cells in R. catesbeiana are similar to those of other amphibia, some characteristic differences are also observed in this species.