Mesenteria

Mesenteria is the plural form of mesenterium, an anatomical term that refers to the mesentery. In English-language anatomy, the singular is usually mesentery and the plural mesenteries, but mesenteria appears in Latin-derived or historical texts as the plural of mesenterium. The mesentery itself is a double layer of peritoneum that attaches parts of the gastrointestinal tract to the posterior abdominal wall and serves as a conduit for blood vessels, nerves, and lymphatics. It also contains fat and lymphatic tissue that contribute to immune and metabolic functions.

Anatomically, there are dorsal mesenteries, which suspend most of the intestines, and ventral mesenteries, which in humans largely regress during development leaving remnants such as the falciform ligament and the lesser omentum. The mesenteria organize the routes of arterial and venous supply, lymphatics, and autonomic nerves to the intestines while allowing a degree of mobility needed for intestinal peristalsis.

Embryology and variation: mesenteries form as the gut elongates and rotates during embryonic development. The arrangement of dorsal versus ventral mesentery varies among species and influences the final organization of the intestinal attachments. In humans, the predominant dorsal mesentery supports the small and portions of the large intestine.

Clinical relevance: diseases can affect the mesenteries or their vessels, including mesenteric ischemia from arterial occlusion, internal hernias through mesenteric defects, and inflammatory conditions such as sclerosing mesenteritis. Imaging and surgical evaluation focus on the integrity and vascular supply of the mesenteria.

Etymology: the term derives from Latin mesenterium, itself from Greek mesenterion, combining elements meaning “middle” and “intestine.” See also mesentery and peritoneum.