The superior mesenteric lymph nodes may be divided into three principal groups: * mesenteric lymph nodes * ileocolic lymph nodes * mesocolic lymph nodes

Structure

Mesenteric lymph nodes

The mesenteric lymph nodes or mesenteric glands are one of the three principal groups of superior mesenteric lymph nodes and lie 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 intestines ...

. They number from one hundred to one hundred and fifty, and are sited as two main groups: * one

ileocolic In many Animalia, including humans, an ileocolic structure or problem is something that concerns the region of the gastrointestinal tract from the ileum to the colon. In Animalia that have ceca, the ileocecal region is a subset of the ileocolic ...

group lying close to the wall of the

small intestine The small intestine or small bowel is an organ in the gastrointestinal tract where most of the absorption of nutrients from food takes place. It lies between the stomach and large intestine, and receives bile and pancreatic juice through the p ...

, among the terminal twigs 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 ...

; * a second larger mesocolic group placed in relation to the loops and primary branches of the vessels.

Ileocolic lymph nodes

The ileocolic lymph nodes, from ten to twenty in number, form a chain around the

ileocolic artery The ileocolic artery is the lowest branch arising from the concavity of the superior mesenteric artery. It passes downward and to the right behind the peritoneum toward the right iliac fossa, where it divides into a superior and an inferior branch ...

, but tend to subdivide into two groups, one near 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 ...

and the other on the lower part of the trunk of the artery. Where the vessel divides into its terminal branches the chain is broken up into several groups: * (a) ileal, in relation to the ileal branch of the artery; * (b) anterior ileocolic, usually of three glands, in the ileocolic fold, near the wall of the

cecum The cecum or caecum is a pouch within the peritoneum that is considered to be the beginning of the large intestine. It is typically located on the right side of the body (the same side of the body as the appendix (anatomy), appendix, to which i ...

; * (c) posterior ileocolic, mostly placed in the angle between the

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 ma ...

and the colon, but partly lying behind the cecum at its junction with the ascending colon; * (d) a single gland, between the layers of the mesenteriole of the appendix; * (e) right colic, along the medial side of the

ascending colon ''Ascending'' is a science fiction novel by the Canadian writer James Alan Gardner, published in 2001 by HarperCollins Publishers under its various imprints.HarperCollins, Avon, HarperCollins Canada, SFBC/Avon; paperback edition 2001, Eos Books. ...

Mesocolic lymph nodes

The mesocolic lymph nodes are numerous, and lie between the layers of the

transverse mesocolon 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 intestine ...

, in close relation to the transverse colon; they are best developed in the neighborhood of the right and left

colic flexures In the anatomy of the human digestive tract, there are two colic flexures, or curvatures in the transverse colon. The right colic flexure is also known as the hepatic flexure, and the left colic flexure is also known as the splenic flexure. Note ...

. One or two small glands are occasionally seen along the trunk of the

right colic artery The right colic artery is an artery of the abdomen, a branch of the superior mesenteric artery supplying the ascending colon. It divides into two terminal branches - an ascending branch and a descending branch - which form anastomoses with the ...

and others are found in relation to the trunk and branches of the middle colic artery.

Function

The superior mesenteric glands receive lymph from 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 previous ...

vermiform process The appendix (or vermiform appendix; also cecal r caecalappendix; vermix; or vermiform process) is a finger-like, blind-ended tube connected to the cecum, from which it develops in the embryo. The cecum is a pouch-like structure of the large i ...

, and the ascending and transverse parts of the colon; lymph drains into the preaortic glands.

Additional images

File:Gray615.png, The lymphatics of cecum and vermiform process from the front. File:Gray616.png, The lymphatics of cecum and vermiform process from behind.

References

Lymphatics of the torso {{lymphatic-stub