Corpus: Mucosa

The term mucosa' refers to the lining of the internal cavities of the organism by a generally uncornified, single- or multi-layered, flat to highly prismatic epithelium. The apical surface of the mucosa is usually covered by a layer of mucus consisting of mucins.

The exact structure of the mucosa differs between the various tissues. In the area of the trunk intestine, the tunica mucosa can be further subdivided into three thin tissue layers (so-called "laminae"):

• Lamina epithelialis mucosae: The actual epithelial layer, also called "epithelium mucosae"
• Lamina propria mucosae: Loose connective tissue with reticulin fibres
• Lamina muscularis mucosae: Thin layer of smooth muscle cells

On the one hand, the mucosa fulfils a barrier function, on the other hand it forms a lubricating film against the respective hollow organ. Depending on its location, the mucosa can perform transport functions through cilia, enable microbial defence through the secretion of antibacterial substances or be involved in the resorption of substances from the organ lumen.

• Oral mucosa
• Nasal mucosa
• Bronchial mucosa
• Anal mucosa
• Gastric mucosa
• Vaginal mucosa

The removal of the mucosa, especially in the case of neoplastic changes, is called mucosectomy.