Intestinal mucosa

Intestinal mucosa is the innermost layer of the gastrointestinal tract. It plays a vital role in the absorption of nutrients, secretion of mucus, and immune function. The intestinal mucosa is composed of three layers: the epithelium, the lamina propria, and the muscularis mucosae.

Structure

The epithelium is the innermost layer of the intestinal mucosa. It is composed of a single layer of cells that are in direct contact with the contents of the gastrointestinal tract. The epithelium is responsible for the absorption of nutrients and the secretion of mucus and digestive enzymes.

The lamina propria is a layer of connective tissue that supports the epithelium. It contains blood vessels, lymphatic vessels, and cells of the immune system. The lamina propria provides nutrients to the epithelium and carries away absorbed materials.

The muscularis mucosae is a thin layer of smooth muscle. It separates the mucosa from the underlying submucosa. The muscularis mucosae contracts to increase the contact between the epithelium and the contents of the gastrointestinal tract, enhancing absorption.

Function

The primary function of the intestinal mucosa is to absorb nutrients from the contents of the gastrointestinal tract. The epithelium contains specialized cells, called enterocytes, that absorb nutrients. Enterocytes have microvilli, small projections that increase the surface area for absorption.

The intestinal mucosa also secretes mucus, which lubricates the contents of the gastrointestinal tract and protects the epithelium from mechanical damage and the action of digestive enzymes. The mucus is secreted by goblet cells, which are scattered among the enterocytes.

The intestinal mucosa plays a crucial role in the immune system. The lamina propria contains lymphocytes and other immune cells that protect the body from pathogens that may enter the gastrointestinal tract.

Clinical significance

Damage to the intestinal mucosa can lead to malabsorption, inflammation, and increased susceptibility to infection. Conditions that can damage the intestinal mucosa include celiac disease, Crohn's disease, and radiation enteritis.

See also

• Gastrointestinal tract
• Epithelium
• Lamina propria
• Muscularis mucosae
• Enterocytes
• Goblet cells
• Lymphocytes
• Celiac disease
• Crohn's disease
• Radiation enteritis