[论文解读] Histological and Histochemical Studies on the Esophagus, Stomach and Small Intestines of Vara-nus niloticus

Ahmed YA, El-Hafez AAE+1 more|arXiv (Cornell University)|Oct 5, 2016

Veterinary Equine Medical Research被引用 5

一句话总结

本研究对尼罗 monitor（Varanus niloticus）的食管、胃和小肠进行了详细的组织学与组织化学分析，采用苏木精-伊苏红、PAS、阿尔辛蓝和格里梅利乌斯染色。主要发现包括：食管内衬有纤毛柱状上皮及杯状细胞，胃分为壁细胞区和幽门腺区，小肠具有吸收细胞和杯状细胞的绒毛结构，肠内分泌细胞分布于上皮和腺体层中。

ABSTRACT

The aim of the current study was to investigate the morphological structure of one of the most common reptilian species in Egypt, Varanus niloticus or Nile monitor. Specimens for histological examination were collected from the esophageus, stomach and small intestine of the Nile monitor and processed for paraffin embedding. Sections were stained with haematoxylin and eosin for general morphology. Periodic Acid Schiff's (PAS) and Alcian Blue (AB) staining methods were applied to detect the different types of the mucous con-tents of the gastro-intestinal tract. Some paraffin sections were stained with Grimelius silver impregnation technique for localization of the enteroendocrine cells. The folded esophageal mucosa had ciliated columnar epithelium with mucous secreting goblet cells, which stained positive with PAS and AB. The esophageal mucosa was folded and the lining epithelium was ciliated columnar epithelium with mucous secreting goblet cells, which stained positive with PAS and AB. The stomach was divided into fundic and pyloric regions. The mucosa was thrown into gastric pits, into which the gastric glands opened. The surface epithelium was mucous secreting columnar cells and stained positive with PAS but negative with AB. The fundic gland was made by oxynticopeptic cells and few mucous cells, while the entire pyloric gland was made by mucous cells stained positive for both PAS and AB. The small intestine showed many villi but occasional poorly developed intestinal crypts were. The intestinal mucosa was lined with absorptive columnar epithelium with goblet cells, which stained positive with PAS and AB. Enteroendocrine cells were of different shapes; rounded, spindle, oval or pyramidal and were localized in the surface epithelium of the esophagus and small intestine, and among the cells of the gastric glands.

研究动机与目标

• 描述埃及常见爬行动物尼罗 monitor（Varanus niloticus）消化道的形态结构。
• 识别食管、胃和小肠上皮衬里类型及黏液分泌物类型。
• 利用格里梅利乌斯银染色法定位肠内分泌细胞。
• 通过 PAS 和阿尔辛蓝染色比较黏液成分的组织化学特征。

提出的方法

• 将尼罗 monitor（Varanus niloticus）食管、胃和小肠组织切片进行石蜡包埋。
• 苏木精-伊苏红染色以观察一般组织学形态。
• 过碘酸-雪夫（PAS）和阿尔辛蓝（AB）染色以检测中性及酸性黏蛋白物质。
• 格里梅利乌斯银浸染法以可视化肠内分泌细胞。
• 显微镜下观察并分析染色组织切片的形态。
• 比较不同消化道区域上皮与腺体结构的差异。

实验结果

研究问题

• RQ1 尼罗 monitor（Varanus niloticus）食管黏膜的组织学结构如何？
• RQ2 胃的壁细胞区与幽门腺区的黏液分泌物有何差异？
• RQ3 尼罗 monitor 消化道中的肠内分泌细胞位于何处？
• RQ4 小肠由哪些类型的上皮细胞衬里，其形态与分布有何差异？
• RQ5 食管、胃和小肠中黏液成分的组织化学特征是什么？

主要发现

• 食管黏膜呈皱褶状，内衬纤毛柱状上皮，含分泌黏液的杯状细胞，PAS 和阿尔辛蓝染色均呈阳性。
• 胃分为壁细胞区和幽门腺区，壁细胞腺含壁细胞和少量黏液细胞，幽门腺则完全由分泌黏液的细胞构成，PAS 和 AB 染色均呈阳性。
• 小肠黏膜具有大量绒毛和少量隐窝，内衬吸收性柱状上皮和杯状细胞，两者均对 PAS 和 AB 染色呈阳性。
• 肠内分泌细胞呈多种形态——圆形、梭形、卵圆形和金字塔形，分布在食管和小肠的表面上皮以及胃腺细胞之间。
• 胃表面上皮由分泌黏液的柱状细胞构成，PAS 染色呈阳性，AB 染色呈阴性，表明其黏液成分为中性。
• 组织化学分析证实消化道中存在中性（PAS 阳性）和酸性（AB 阳性）黏液成分，且不同区域的分泌类型与分布存在差异。