The intestinal arteries arise from the convex side of the

superior mesenteric artery In human anatomy, the superior mesenteric artery (SMA) is an artery which arises from the anterior surface of the abdominal aorta, just inferior to the origin of the celiac trunk, and supplies blood to the intestine from the lower part of the du ...

. They are usually from twelve to fifteen in number, and are distributed to the

jejunum The jejunum is the second part of the small intestine in humans and most higher vertebrates, including mammals, reptiles, and birds. Its lining is specialised for the absorption by enterocytes of small nutrient molecules which have been previou ...

and

ileum The ileum () is the final section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear and the terms posterior intestine or distal intestine m ...

Nomenclature

The term "intestinal arteries" can be confusing, because these arteries only serve a small portion of the

intestines The gastrointestinal tract (GI tract, digestive tract, alimentary canal) is the tract or passageway of the digestive system that leads from the mouth to the anus. The GI tract contains all the major organs of the digestive system, in humans and ...

. * They do not supply any of the

large intestine The large intestine, also known as the large bowel, is the last part of the gastrointestinal tract and of the digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces before bein ...

. The large intestine is primarily supplied by the right colic artery,

middle colic artery The middle colic artery is an artery of the abdomen; a branch of the superior mesenteric artery distributed to parts of the ascending and transverse colon. It usually divides into two terminal branches - a left one and a right one - which go on ...

, and

left colic artery The left colic artery is a branch of the inferior mesenteric artery distributed to the descending colon, and left part of the transverse colon. It ends by dividing into an ascending branch and a descending branch; the terminal branches of the two ...

. * They do not supply the

duodenum The duodenum is the first section of the small intestine in most higher vertebrates, including mammals, reptiles, and birds. In fish, the divisions of the small intestine are not as clear, and the terms anterior intestine or proximal intestine m ...

of the

small intestine The small intestine or small bowel is an organ (anatomy), organ in the human gastrointestinal tract, gastrointestinal tract where most of the #Absorption, absorption of nutrients from food takes place. It lies between the stomach and large intes ...

. The duodenum is primarily supplied by the

inferior pancreaticoduodenal artery The inferior pancreaticoduodenal artery (the IPDA) is a branch of the superior mesenteric artery. It supplies the head of the pancreas, and the ascending and inferior parts of the duodenum. Rarely, it may have an aneurysm. Structure The inferio ...

and

superior pancreaticoduodenal artery The superior pancreaticoduodenal artery is an artery that supplies blood to the duodenum and pancreas. Structure It is a branch of the gastroduodenal artery, which most commonly arises from the common hepatic artery of the celiac trunk, althou ...

. For clarity, some sources prefer instead using the more specific terms ileal arteries and jejunal arteries.

Path

They run nearly parallel with one another between the layers of the

mesentery The mesentery is an organ that attaches the intestines to the posterior abdominal wall in humans and is formed by the double fold of peritoneum. It helps in storing fat and allowing blood vessels, lymphatics, and nerves to supply the intesti ...

, each vessel dividing into two branches, which unite with adjacent branches, forming a series of arches (

arterial arcades An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the p ...

), the convexities of which are directed toward the intestine. From this first set of arches branches arise, which unite with similar branches from above and below and thus a second series of arches is formed; from the lower branches of the artery, a third, a fourth, or even a fifth series of arches may be formed, diminishing in size the nearer they approach the intestine. In the short, upper part of the mesentery only one set of arches exists, but as the depth of the mesentery increases, second, third, fourth, or even fifth groups are developed. The differences between the ileal arteries and the jejunal arteries can be summarized as follows: From the terminal arches numerous small straight vessels ( vasa recta) arise which encircle the intestine, upon which they are distributed, ramifying between its coats. From the intestinal arteries small branches are given off to the

lymph glands A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that include ...

and other structures between the layers of the mesentery.

Additional images

File:Intestinal arteries.JPG, Superior mesenteric artery File:Slide4gen.JPG, Intestinal arteries of the superior mesenteric artery.Plastination technique .

References

External links

* Arteries of the abdomen {{Portal bar, Anatomy