What are the mesenteries? How many do we have, what are they, and what are their functions?

What are Mesenteries?

Mesenteries are thin, fan-shaped folds of tissue that attach the intestines and other abdominal organs to the abdominal wall. They are composed primarily of peritoneum, which is a serous membrane that also covers the abdominal organs. Mesenteries serve important functions in the body.

How Many Mesenteries Do We Have?

There are several mesenteries in the human body, primarily categorized by the organs they support. The major mesenteries include:

1. Mesentery Proper: Attaches the small intestine to the posterior abdominal wall.
2. Mesocolon: Connects the colon to the abdominal wall and can be further categorized into:
   • Transverse Mesocolon
   • Sigmoid Mesocolon
3. Lesser Omentum: Connects the stomach to the liver.
4. Greater Omentum: A large fold of peritoneum that hangs down from the stomach.
5. Falciform Ligament: Connects the liver to the anterior abdominal wall.

Functions of Mesenteries

1. Support and Suspension: Mesenteries help to support and suspend the intestines and other abdominal organs, preventing them from twisting or collapsing.
2. Vascular and Nerve Supply: They contain blood vessels, lymphatics, and nerves that supply the intestines with the necessary nutrients and communication pathways.
3. Fat Storage: Certain mesenteries, like the greater omentum, also store fat, which serves as energy reserves.
4. Immune Function: The mesenteric tissues contribute to immune responses by housing various immune cells.

In summary, mesenteries are essential anatomical structures that not only provide structural support but also play significant roles in the vascular and immune functions of the gastrointestinal system.