Mesentery Horizontal disposition of the peritoneum in the lower part of the abdomen. The mesentery is marked with red. Vertical disposition of the peritoneum. Main cavity, red; omental bursa, blue. Gray's subject #246 1157 MeSH Mesentery
In anatomy, the mesentery is the double layer of peritoneum that suspends the jejunum and ileum from the posterior wall of the abdomen. Its meaning, however, is frequently extended to include double layers of peritoneum connecting various components of the abdominal cavity.
The mesentery proper (i.e. the original definition) refers to the peritoneum responsible for connecting the jejunum and ileum (parts of the small intestine) to the back wall of the abdomen. Between the two sheets of peritoneum are blood vessels, lymph vessels, and nerves. This allows these parts of the small intestine to move relatively freely within the abdominopelvic cavity. The brain, however, cannot map sensation accurately, so sensation is usually referred to the midline, an example of referred pain.
The root of proper mesentery extends 15 cm from duodenojejunal flexure at the level of left side of L2 obliquely (toward inferior right) to the ileocecal junction in the right iliac fossa at the level of right sacroiliac joint. The root of mesentery crosses the second and third parts of duodenum, abdominal aorta, Inferior vena cava, right ureter, right psoas major muscle, and right gonadal artery.
The mesentery is derived from what is known in the embryo as the dorsal mesentery. The dorsal mesentery is larger than the ventral mesentery, which gradually becomes other parts of the peritoneum. Most parts of the ventral mesentery are associated with the liver.
Mesenteries are composed of two layers of peritoneum. The peritoneum that lies on the walls of the abdominopelvic cavity (parietal peritoneum) invaginates at certain parts, with an organ inside this invagination. This invaginated peritoneum (visceral peritoneum) will often surround all but a part of the organ ("bare area"), through which the organ transmits blood vessels and nerves. If this organ is invaginated far enough into the peritoneum, the visceral peritoneum will come in contact with itself, forming the organ's mesentery.
Mesenteries in the body:
- Mesentery (proper) - surrounds parts of the small intestine (the jejunum and the ileum)
- Mesocolon - surrounds parts of the colon
- Broad ligament of the uterus - peritoneum of the uterus, uterine tubes, and ovaries
A lack of blood-supply to the mesentery causes mesenteric ischemia.
- SUNY Labs 39:01-0100
- jejunumileum at The Anatomy Lesson by Wesley Norman (Georgetown University)
- -1724579760 at GPnotebook
Abdominopelvic cavity: Abdomen/Abdominal cavity and Pelvis/Pelvic cavity and Peritoneal cavity (TA A10, TH H3.04.08, GA 4.408 and GA 11.1147) Extraperitoneal spaceRetroperitoneal space · Retropubic space Peritoneal ligaments,
mesenteries, and foldsAbdominalFrom ventral mesenteryFrom dorsal mesenteryUmbilical folds (Supravesical fossa, Medial inguinal fossa, Lateral umbilical fold, Lateral inguinal fossa) · Ileocecal foldGeneralUrogenital peritoneumUterus/ovariesRecesses
Prenatal development/Mammalian development of digestive system, coelom and septa, and mesenchymal mesenteric masses (GA 11.1101, TE E5.4, 5.8-9) GutUpper GI tract and accessory AbdominopelvicMesenteryOtherIntra-embryonic coelom · Extra-embryonic coelom
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Mesentery — Mes en*ter*y (?; 277), n. [Gr. mesente rion, me sos + e nteron intestine: cf. F. m[ e]sent[ e]re.] [1913 Webster] 1. (Anat.) The membranes, or one of the membranes (consisting of a fold of the peritoneum and inclosed tissues), which connect the… … The Collaborative International Dictionary of English
mesentery — (n.) fold of the peritoneum, early 15c., from medical L. mesenterium middle of the intestine, from medical Gk. mesenterion, from mesos middle (see MEDIAL (Cf. medial) (adj.)) + enteron intestine (see ENTERIC (Cf. enteric)). Related: Mesenteric … Etymology dictionary
mesentery — [mes′ən ter΄ē, mez′ən ter΄ē] n. pl. mesenteries [ML mesenterium < Gr mesenterion < mesos,MID1 + enteron, intestine: see INTER ] a supporting membrane or membranes enfolding some internal organ and attaching it either to the body wall or to… … English World dictionary
Mesentery — A fold of tissue which attaches organs to the body wall. The word mesentery usually refers to the small bowel mesentery which anchors the small intestine to the back of the abdominal wall. Blood vessels, nerves, and lymphatics branch through the… … Medical dictionary
mesentery — noun (plural teries) Etymology: Middle English mesenterie, from Medieval Latin mesenterion, from Greek, from mes + enteron intestine more at inter Date: 15th century 1. a. one or more vertebrate membranes that consist of a double fold of the… … New Collegiate Dictionary
mesentery — double membranes meeting in the midline above and below the viscera formed by the serous membranes in the peritoneal and pericardial cavities. The mesentery in the pericardial cavity disappears during embryonic development and most the the… … Dictionary of ichthyology
mesentery — mesenteric, adj. /mes euhn ter ee, mez /, n., pl. mesenteries. Anat. the membrane, consisting of a double layer of peritoneum, that invests the intestines, attaching them to the posterior wall of the abdomen, maintaining them in position in the… … Universalium
mesentery — n. membrane enclosing intestines. ♦ mesenterial, ♦ mesenteric, a. ♦ mesenteritis, n. inflammation of mesentery … Dictionary of difficult words
mesentery — n. [Gr. mesos, middle; enteron, gut] A supporting membrane or one that forms a partition … Dictionary of invertebrate zoology
mesentery — noun The membrane that attaches the intestines to the wall of the abdomen, maintaining their position in the abdominal cavity, and supplying them with blood vessels, nerves, and lymphatics … Wiktionary