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 ...

. 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 specialized for the absorption by enterocytes of small nutrient molecules which have been pr ...

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 may ...

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 tract is the largest of the body's systems, after the cardiovascular system. ...

. * 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 Digestion, digestive system in tetrapods. Water is absorbed here and the remaining waste material is stored in the rectum as feces befor ...

. The large intestine is primarily supplied by the right colic artery, middle colic artery, 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 vertebrates, including mammals, reptiles, and birds. In mammals, it may be the principal site for iron absorption. The duodenum precedes the jejunum and ileum and is the shortest p ...

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, altho ...

. 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 In human anatomy, the mesentery is an Organ (anatomy), organ that attaches the intestines to the posterior abdominal wall, consisting of a double fold of the peritoneum. It helps (among other functions) in storing Adipose tissue, fat and allowi ...

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

arterial arcades The arterial arcades (intermesenteric arterial anastomoses or Riolan arcades) are a series of anastomosing arterial arches between the arterial branches of the jejunum and ileum. Nearest the duodenum the mesenteric loops are primary, the vasa rec ...

), 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 The lymphatic system, or lymphoid system, is an organ system in vertebrates that is part of the immune system and complementary to the circulatory system. It con ...

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