The esophagus of the crocodilian Caiman latirostris (Reptilia, Crocodylia ): histologia, histochemical, and immunohistochemical study

ABSTRACT

The purpose of this study was to analyze the esophageal morphology of Caiman latirostris using histochemicaland immunohistochemical techniques. The mucosae layer is composed of a pseudostratified columnarepithelium with goblet cells that occasionally form intra-epithelial glands. The goblet cells showed differentaffinity for the histochemical techniques. The lamina propria is composed of loose connective tissue with bloodvessels. The smooth muscle fibers that compose the muscularis mucosa are thick and form a clear demarcationbetween the mucosa layer and adjacent submucosa. There are no glands in the esophageal submucosa. Themuscle layer is composed a circular internal layer and a longitudinal external one. The adventitia layer iscomposed of loose connective tissue and blood vessels. The serotonin immunoreactive (IR) cells were notpreferentially distributed in any region of the epithelium, ranging from the base of the intra-epithelial gland tothe connection to the lumen. Somatostatina, glucagon and CCK IR cells were not detected.