蓝尾石龙子消化道内分泌细胞的免疫组织化学研究(英文)

IMMUNOHISTOCHEMICAL STUDY OF ENDOCRINE CELLS IN THE DIGESTIVE TRACT OF EUMECES ELEGANS

目的阐明蓝尾石龙子消化道内分泌细胞的形态学特征、类型、局部分布和细胞密度。方法应用免疫组织化学技术链霉卵白素-过氧化物酶(S-P)法。结果蓝尾石龙子消化道中的内分泌细胞形态多样,呈圆形、椭圆形、纺锤形、梭形、锥形、烧瓶形和杆状。蓝尾石龙子消化道中显示出3种内分泌细胞,即5-羟色胺阳性细胞、生长抑素阳性细胞和胃泌素阳性细胞,未见高血糖素阳性细胞、P物质阳性细胞、胰岛素阳性细胞和胰多肽阳性细胞。5-羟色胺阳性细胞是消化道中最主要的内分泌细胞类型,其在消化道各段均有分布,但在各段分布密度不同。生长抑素阳性细胞仅分布于胃部。胃泌素阳性细胞局限分布于幽门和十二指肠部位。在蓝尾石龙子消化道内具有最多种类型内分泌细胞分布的部位是幽门,同时消化道内各种内分泌细胞在此部位也显示出最高的分布密度。结论蓝尾石龙子与其他爬行动物消化道内分泌细胞在分布上存在一定的共同特征并具其独特性,这些共同特征可能反映着不同脊椎动物消化生理的相同点。

Objective To clarify the morphological features, types, regional distributions and cell densities of gastrointestinal （GI） endocrine ceils in various parts of the digestive track （DT） of Eumeces elegans. Methods Using immunohistochemical techniques of streptavidin-peroxidase（S-P） method. Results The endocrine cells found in the DT were round or oval, spindle, shuttle, pyramid, flask and bacilliform in shape. Three types of endocrine cells, namely 5- hydroxytryptamine （5-HT） positive cells, somatostatin （SS） positive cells and gastrin（GAS） positive cells were found, No substance P（ SP）-, glucagon （ GLU）-, pancreatic polypeptide （ PP）- and insulin （INS） positive cells were detected. 5-HT positive cells distributed throughout the whole DT at various densities and they were most predominant cell types in the DT. SS positive cells were detected only in stomach. GAS positive cells showed a restricted distribution and were only demonstrated in the pylorus and duodenum. In the DT of E. elegans the region with the highest degree of cell type heterogeneity was pylorus and all types of endocrine cell along the DT showed peak density in the pylorus as well. Conclusion Some common features of the distribution of different types of GI endocrine cells are found between E. elegans and other reptiles. This common trait may reflect the similarity in digestive physiology of various vertebrates. On the other hand, some species-dependent unique distribution features of endocrine cells in DT were also detected in E. elegans.