Mesenteric arteries

The arteries that supply blood to the intestines, essential for nutrient absorption and digestion.

Mesenteric arteries are vital blood vessels branching from the abdominal aorta. They comprise the superior mesenteric artery (SMA) and the inferior mesenteric artery (IMA), responsible for delivering oxygenated blood to the small and large intestines, respectively. Each artery serves different segments of the intestinal tract, ensuring adequate blood flow for optimal digestive function.

Terminologia Anatomica

arteriae mesentericae

System

Circulatory system

Function

The primary function of the mesenteric arteries is to supply blood to the intestines, which is crucial for their complex roles in digestion and nutrient absorption. The superior mesenteric artery primarily supplies the small intestine, as well as the first part of the large intestine, including the cecum and appendix, colon, and a portion of the pancreas. By delivering oxygen-rich blood, the SMA supports the metabolic activities of enterocytes, the cells lining the intestines involved in absorption. Meanwhile, the inferior mesenteric artery provides blood to the distal sections of the large intestine, including the descending colon, sigmoid colon, and rectum. This vascular supply plays a critical role in maintaining the health of intestinal tissues, facilitating the absorption of nutrients, and supporting the diverse microbial ecosystem that thrives in the gut. Any disruption in blood flow from these arteries can lead to serious gastrointestinal problems, demonstrating their importance within the body's digestive system.

Location

The mesenteric arteries are located in the abdominal cavity, originating from the abdominal aorta, which is the main blood vessel supplying blood to the lower body. The superior mesenteric artery arises from the aorta at approximately the level of the first lumbar vertebra (L1), traveling downward and branching out into several arteries that supply the upper portions of the intestines. The inferior mesenteric artery, situated slightly lower, branches off from the abdominal aorta at the level of the third lumbar vertebra (L3). As they extend, each artery fans out to form an extensive network of smaller arteries and arterioles that penetrate the intestinal walls, ensuring an adequate blood supply to the digestive organs.

Did You Know?

The superior mesenteric artery supplies around 75% of the blood flow to the intestines, underscoring its critical role in digestion.
The mesenteric arteries are not only vital for nutrient delivery but also play a role in immune responses within the gut, helping to regulate inflammation and pathogen clearance.
Ischemia (reduction in blood flow) in the mesenteric arteries can lead to serious conditions like mesenteric ischemia, which can threaten intestinal viability.