Comparative microanatomical and histochemical biodistribution profiles of different types of mucins in oesophageal gastric tract mucosa of some tetrapod representatives

AbstractThe microanatomical features of the oesophageal gastric tract in tetrapod representatives and their function, especially those related to the mucosal layer, have not yet been fully investigated. The mucosal layer cells and their function in the oesophageal gastric tract differ structurally and functionally in tetrapod representatives based on interspecies difference and the type of food and feeding habits. The present study was, therefore, postulated to compare the mucosal microanatomical structure and histochemical biodistribution of different mucin types in oesophageal gastric tract tissues of four tetrapod species. A representative of each tetrapod class was selected, as follows: the Egyptian toadBufo regularis, the lizardTrachylepis quinquetaeniata, the domestic pigeonColumba livia domestica and the albino mouseMus musculus for Amphibia, Reptilia, Aves and Mammalia, respectively. Microanatomically, in lower tetrapods (toad and lizard), the mucosal layer of the oesophagus was composed of simple ciliated columnar epithelium with goblet cells, whereas in higher tetrapods (pigeon and mouse) it was composed of stratified squamous epithelium, with non-keratinised epithelium in the pigeon but keratinised epithelium in the mouse. However, the gastric mucosal layer of the stomach in lower tetrapods consists of simple columnar epithelium and gastric glands. Similarly, the mucosa of the pigeon ’s proventriculus consists of simple columnar epithelium with proventricular gla...
Source: Histochemistry and Cell Biology - Category: Biomedical Science Source Type: research