Spleen
Spleen
Laparoscopic view of a horse's spleen (the purple and grey mottled organ)
Latin	splen, lien
Gray's	subject #278 1282
Artery	Splenic artery
Vein	Splenic vein
Nerve	Splenic plexus
Precursor	Mesenchyme of dorsal mesogastrium
MeSH	Spleen
Dorlands/Elsevier	s_19/12750780

The spleen is an organ found in all vertebrate animals^[1]. Laparoscopic surgery, also called Minimally invasive surgery (MIS, bandaid surgery, Keyhole surgery, or pinhole surgery Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome. Gray's Anatomy the Respiratory apparatus ( Apparatus Respiratorius Respiratory system Respiratory apparatus Arteries are Blood vessels that carry blood away from the Heart. In Anatomy, the splenic artery (in the past called the lienal artery) is the Blood vessel that supplies oxygenated Blood to the Spleen In the Circulatory system, a vein is a Blood vessel that carries Blood back toward the Heart (as opposed to Artery, a blood vessel In Anatomy, the splenic vein (in the past called the lienal vein) is the Blood vessel that drains Blood from the Spleen. A nerve is an enclosed cable-like bundle of peripheral Axons (the long slender projections of Neurons. The splenic plexus ( lienal plexus in older texts is formed by branches from the Celiac plexus, the left Celiac ganglion, and from the right Vagus Embryology (from Greek grc ἔμβρυον embryon, "unborn embryo" and grc -λογία -logia) is the study of the development Mesenchyme refers to loosely organized connective tissue present in the embryo regardless of origin The portion of Mesentery attached to the Greater curvature of the Stomach is named the dorsal mesentery (or dorsal mesogastrium, when referring Medical Subject Headings ( MeSH) is a huge Controlled vocabulary (or metadata system for the purpose of indexing journal articles and books Elsevier, the world's largest Publisher of Medical and Scientific literature, forms part of the Reed Elsevier group Vertebrates are members of the Subphylum Vertebrata, Chordates with backbones or spinal columns The grouping sometimes includes In humans, the spleen is located in the abdomen of the body, where it functions in the destruction of redundant red blood cells and holds a reservoir of blood. Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood It is regarded as one of the centers of activity of the reticuloendothelial system (part of the immune system). The reticuloendothelial system ( RES) part of the Immune system, consists of the phagocytic cells located in Reticular connective tissue, primarily An immune system is a collection of mechanisms within an Organism that protects against Disease by identifying and killing Pathogens and Tumor It is increasingly recognized that its absence leads to a predisposition to certain infections. An infection is the detrimental Colonization of a host Organism by a foreign Species. ^[2]

Contents 1 Anatomy 2 Function 3 Disorders 4 Etymology and cultural views 5 See also 6 Additional images 7 Footnotes 8 External links

Anatomy

The human spleen is located in the upper left part of the abdomen, behind the stomach and just below the diaphragm. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus In Vertebrates such as Mammals the abdomen (belly constitutes the part of the body between the Thorax (chest and Pelvis. In Human anatomy, the stomach is a J-shaped hollow muscular organ of the Gastrointestinal tract involved in the second phase of Digestion, following For other types of diaphragm see Diaphragm. In the Anatomy of Mammals the thoracic diaphragm is a sheet of Muscle In normal individuals this organ measures about 125 × 75 × 50 mm (5 × 3 × 2 inches) in size, with an average weight of 150 grams (5 oz). Inches redirects here To see the Les Savy Fav album see Inches. This article is about the unit of mass For the unit of force see Pound-force.

The spleen consists of masses of lymphoid tissue of granular appearance located around fine terminal branches of veins and arteries. The lymphatic system in Vertebrates is a network of conduits that carry a clear fluid called Lymph. Tissue is a cellular organizational level intermediate between cells and a complete organism In the Circulatory system, a vein is a Blood vessel that carries Blood back toward the Heart (as opposed to Artery, a blood vessel Arteries are Blood vessels that carry blood away from the Heart. These vessels are connected by modified capillaries called splenic sinuses. Capillaries are the smallest of a body's Blood vessels measuring 5-10 μm in diameter which connect Arterioles and Venules and enable the interchange

Approximately 10% of people have one or more accessory spleens. An accessory spleen ( supernumerary spleen, splenule, or splenunculus) is a small nodule of splenic tissue found in some people in the neighborhood They may form near the hilum of the main spleen, the junction at which the splenic vessels enter and leave the organ.

There are several peritoneal ligaments that support the spleen^[3] (to understand their naming it helps to know that "lien" is an alternate root for "spleen")

• gastrolienal ligament (gastrosplenic) - connects stomach to spleen. In higher Vertebrates the peritoneum is the Serous membrane that forms the lining of the abdominal cavity &mdash it covers most of the intra-abdominal In Anatomy, the term ligament is used to denote three different types of structures Fibrous tissue that connects Bones to other bones The root is the primary lexical unit of a Word, which carries the most significant aspects of semantic content and cannot be reduced into smaller constituents The gastrosplenic ligament ( ligamentum gastrosplenicum or gastrolienal ligament) is part of the Greater omentum.
• lienorenal ligament (splenorenal) - connects spleen to kidney. The splenorenal ligament (or lienorenal ligament, or phrenicolienal ligament) is derived from the Peritoneum, where the wall of the general peritoneal
• phrenicocolic ligament - connects left colic flexure to the thoracic diaphragm. A fold of Peritoneum, the phrenicocolic ligament, is continued from the Left colic flexure to the Thoracic diaphragm opposite the tenth and The splenic (or left colic flexure is a sharp bend between the transverse and the descending colon in the Left upper quadrant of humans For other types of diaphragm see Diaphragm. In the Anatomy of Mammals the thoracic diaphragm is a sheet of Muscle The middle connects to the spleen.

Cross sections of the spleen reveal a red soft surface which is divided into two types of pulp which correspond to the two most important functional roles of the spleen, summarized in the next section. ^[4]

Function

Area	Function	Composition
red pulp	Mechanical filtration. The red pulp (also called splenic pulp, but should not be confused with White pulp) is a soft mass of a dark reddish-brown color resembling Grumous blood Removes unwanted materials from the blood, including old red blood cells. Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood	"sinuses" (or "sinusoids") which are filled with blood "splenic cords" of reticular fibers "marginal zone" bordering on white pulp
white pulp	Helps fight infections. Sinus is Latin for "bay" "pocket" "curve" or "bosom" A sinusoid is a small Blood vessel similar to a Capillary but with a Discontinuous Endothelium. Blood is a specialized Bodily fluid that delivers necessary substances to the body's cells ��such as nutrients and oxygen—and transports Waste products The Cords of Billroth (also known as splenic cords or red pulp cords) are found in the Red pulp of the Spleen between the sinusoids Reticular fibers or reticulin is a histological term used to describe a type of Structural fiber composed of Type III collagen. The marginal zone is the region at the interface between the non-lymphoid Red pulp and the Lymphoid White-pulp of the Spleen. This article describes the anatomic term white pulp White pulp is also the name of a raw material in Paper production	Composed of nodules, called Malpighian corpuscles. These are composed of: "lymphoid follicles" (or "follicles"), rich in B-lymphocytes "periarteriolar lymphoid sheaths" (PALS), rich in T-lymphocytes

Other functions of the spleen are less prominent, especially in the healthy adult:

• Production of opsonins, properdin, and tuftsin. A Lymph node ( lɪmf noʊd is an organ consisting of many types of cells and is a part of the Lymphatic system. B cells are Lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response, which is governed by Periarteriolar lymphoid sheaths (or periarterial lymphatic sheaths, or PALS) are a portion of the White pulp of the Spleen. T cells belong to a group of White blood cells known as Lymphocytes, and play a central role in Cell-mediated immunity. An opsonin is any molecule that acts as a binding Enhancer for the process of Phagocytosis, for example by coating the negatively-charged molecules on the membrane Properdin or factor P is a Globulin Protein found in the blood serum of higher Animals In the complement system an innate-immunity Tuftsin is a Tetrapeptide (Thr-Lys-Pro-Arg produced by enzymatic cleavage of the Fc-domain of the heavy chain of Immunoglobulin G.

• Creation of red blood cells. Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood While the bone marrow is the primary site of hematopoeisis in the adult, up until the fifth month of gestation, the spleen has important hematopoietic functions. Bone marrow is the flexible tissue found in the hollow interior of Bones In adults marrow in large bones produces new Blood cells It constitutes 4% of Haematopoiesis (from Ancient Greek haima blood poiesis to make (or hematopoiesis in the United States sometimes also haemopoiesis or After birth, erythropoietic functions cease except in some hematologic disorders. As a major lymphoid organ and a central player in the reticuloendothelial system the spleen retains the ability to produce lymphocytes and, as such, remains an hematopoietic organ.

• Storage of red blood cells and other formed elements. Red blood cells are the most common type of Blood cell and the Vertebrate body's principal means of delivering Oxygen to the body tissues via the Blood This is only valid for certain mammals, such as dogs and horses. In horses roughly 50% of the red blood cells are stored there. The red blood cells can be released when needed ^[5] These animals also have large hearts in relation to their body size to accommodate the higher-viscosity blood that results. Viscosity is a measure of the resistance of a Fluid which is being deformed by either Shear stress or Extensional stress. In humans, however, the spleen does not function as a depository of red blood cells, but instead it stores platelets in case of an emergency. Some athletes have tried doping themselves with their own stored red blood cells to try to achieve the same effect, but the human heart is not equipped to handle the higher-viscosity blood. The heart is a muscular organ in all Vertebrates responsible for pumping Blood through the Blood vessels by repeated rhythmic

Disorders

Main article: Splenic disease

Disorders include splenomegaly, where the spleen is enlarged by various reasons. Splenic diseases include Splenomegaly, where the spleen is enlarged by various reasons Splenomegaly is an enlargement of the Spleen, which usually lies in the left upper quadrant (LUQ of the Human abdomen. On the other hand, a lack of normal spleen function is called asplenia. This article is about the medical condition For the Moth Genus, see Armadini.

Etymology and cultural views

The word spleen comes from the Greek splēn. Greek (el ελληνική γλώσσα or simply el ελληνικά — "Hellenic" is an Indo-European language, spoken today by 15-22 million people mainly In Latin its name is lien. Latin ( lingua Latīna, laˈtiːna is an Italic language, historically spoken in Latium and Ancient Rome.

In French, spleen refers to a state of pensive sadness or melancholy. French ( français,) is a Romance language spoken around the world by 118 million people as a native language and by about 180 to 260 million people It has been popularized by the poet Charles Baudelaire (1821-1867) but was already used before, in particular in the Romantic literature (18th century). Year 1821 ( MDCCCXXI) was a Common year starting on Monday (link will display the full calendar of the Gregorian Calendar (or a Common year Year 1867 ( MDCCCLXVII) was a Common year starting on Tuesday (link will display the full calendar of the Gregorian calendar (or a Common year starting Romanticism is a complex artistic literary and intellectual movement that originated in the second half of the 18th century in Western Europe, and gained strength during the The 18th century lasted from 1701 to 1800 in the Gregorian calendar, in accordance with the Anno Domini / Common Era numbering system The connection between spleen (the organ) and melancholy (the temperament) comes from the humoral medicine of the ancient Greeks. Humorism, or humoralism, was a theory of the makeup and workings of the human body adopted by Greek and Roman physicians and philosophers The Greeks ( Greek: Έλληνες) are a Nation and Ethnic group native to Greece, Cyprus and neighbouring regions One of the humours (body fluid) was the black bile, secreted by the spleen organ and associated with melancholy. Bile or gall is a bitter yellow or green Alkaline fluid secreted by Hepatocytes from the Liver of most Vertebrates In many species In contrast, the Talmud (tractate Berachoth 61b) refers to the spleen as the organ of laughter, possibly suggesting a link with the humoral view of the organ. The Talmud ( Hebrew: he תַּלְמוּד is a record of Rabbinic discussions pertaining to Jewish law, ethics, customs and history Humorism, or humoralism, was a theory of the makeup and workings of the human body adopted by Greek and Roman physicians and philosophers

In German, the word "spleen", pronounced as in English, refers to a persisting somewhat eccentric (but not quite lunatic) idea or habit of a person; however the organ is called "Milz", (cognate with Old English milte). The German language (de ''Deutsch'') is a West Germanic language and one of the world's major languages.

In eighteenth- and nineteenth-century England, women in bad humour were said to be afflicted by the spleen, or the vapours of the spleen. In modern English, "to vent one's spleen" means to vent one's anger, e. Anger is an emotional state that may range from minor irritation to intense rage g. by shouting, and can be applied to both males and females; similarly, the English term "splenetic" is used to describe a person in a foul mood.

In China, the spleen '脾 (pí)' counts as the seat of one's temperament and is thought to influence the individual's willpower. China ( Wade-Giles ( Mandarin) Chung¹kuo² is a cultural region, an ancient Civilization, and depending on perspective a National Analogous to "venting one's spleen", "發脾氣" is used as an expression for getting angry, although in the view of Traditional Chinese Medicine, the view of "脾" does not correspond to the anatomical "spleen". Traditional Chinese medicine (also known as TCM,) includes a range of traditional medical practices originating in China.

In chiropractic (meric chart) problems with the spleen relate to T8 (eighth thorasic vertebrea), a subluxation at T8 is associated with low energy and/or low immune system function.

In infants it is not very common for the spleen to destroy red blood cells faster than the liver can conjugate the bilirubin. Bilirubin (formerly referred to as hematoidin) is the yellow breakdown product of normal Heme Catabolism. The effect of this would be more bilirubin in the blood plasma.

See also

• marginal zone

Additional images

The celiac artery and its branches. The marginal zone is the region at the interface between the non-lymphoid Red pulp and the Lymphoid White-pulp of the Spleen.	The celiac artery and its branches.	Horizontal disposition of the peritoneum in the upper part of the abdomen.	Transverse section through the middle of the first lumbar vertebra.
The duodenum and pancreas.	The visceral surface of the spleen.	Transverse section of the spleen, showing the trabecular tissue and the splenic vein and its tributaries.	Transverse section of the human spleen, showing the distribution of the splenic artery and its branches.
Section of the spleen, showing the termination of the small bloodvessels.	Back of lumbar region, showing surface markings for kidneys, ureters, and spleen.	Side of thorax, showing surface markings for bones, lungs (purple), pleura (blue), and spleen (green).	Lymphatic system

Footnotes

External links

• SUNY Figs 38:03-01 - "The visceral surface of the spleen. The State University of New York Health Science Center at Brooklyn, better known as SUNY Downstate Medical Center, is an academic medical center and is the only one of its kind "
• SUNY Anatomy Image 7881
• "spleen" from Encyclopedia Britannica Online
• [1] from "Spleen and Lymphatic System at Family Doctor. The Encyclopædia Britannica is a general English-language encyclopaedia published by Encyclopædia Britannica Inc org"
• [2] from "Medline Plus Spleen Diseases"

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