spleen


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Related to spleen: liver, pancreas, Ruptured spleen

spleen

 [splēn]
a large glandlike but ductless organ in the upper part of the abdominal cavity on the left side, lateral to the cardiac end of the stomach. Called also lien. adj., adj splen´ic. It is the largest collection of reticuloendothelial cells in the body and is composed of spongelike tissue of two types: red pulp, which is the dark reddish brown substance filling the interspaces of the sinuses of the spleen, and white pulp, which consists of sheaths of lymphatic tissue surrounding the arteries of the spleen. It is enclosed in a dense capsule. In a normal adult the spleen is about 12.5 cm long and weighs about 140 to 210 g. After gastric digestion and in the presence of disease the spleen enlarges.



During fetal life the spleen and liver produce erythrocytes, but after birth that function is taken over by the bone marrow. However, if there is bone marrow failure, the spleen may again produce erythrocytes. In the normal adult the spleen is a reservoir for blood, and contains a high concentration of erythrocytes. In times of exertion, emotional stress, pregnancy, severe bleeding, carbon monoxide poisoning, or other occasions when the oxygen content of the blood must be increased, the spleen contracts rhythmically to release its store of erythrocytes into the bloodstream.

The spleen also acts to help keep the blood free of unwanted substances, including wastes and infecting organisms. The blood is delivered to it by the splenic artery, and passes through smaller branch arteries into a network of channels lined with leukocytes known as phagocytes (see reticuloendothelial system). These clear the blood of old erythrocytes, damaged cells, parasites, and other toxic or foreign substances. Hemoglobin from the removed red cells is temporarily stored.
accessory spleen a small mass of tissue elsewhere in the body, histologically and functionally identical with that composing the normal spleen.

spleen

(splēn), [TA]
A large, vascular lymphatic organ lying in the upper part of the abdominal cavity on the left side, between the stomach and diaphragm, composed of white and red pulp; the white consists of lymphoid nodules and diffuse lymphoid tissue; the red consists of venous sinusoids between which are splenic cords; the stroma of both red and white pulp is composed of reticular fibers and cells. A framework of fibroelastic trabeculae extending from the capsule conveys blood vessels to and from the splenic pulp. The spleen is a blood-forming organ in early life and later a storage organ for red corpuscles and platelets; because of the large number of macrophages present in the spleen it also acts as a blood filter, identifying and destroying effete erythrocytes as well as participating in the immune defense of the body.
Synonym(s): splen [TA], lien
[G. splēn]

spleen

(splēn)
n.
1.
a. A large, highly vascular lymphoid organ, lying in the human body to the left of the stomach below the diaphragm, serving to store blood, disintegrate old blood cells, filter foreign substances from the blood, and produce lymphocytes.
b. A homologous organ or tissue in other vertebrates.
c. Obsolete This organ conceived as the seat of emotions or passions.
2. Ill temper: vent one's spleen.
3. Archaic Melancholy.
4. Obsolete A whim; a caprice.

spleen′y adj.

spleen

(splēn) [TA]
A large vascular lymphatic organ lying in the upper part of the abdominal cavity on the left side, between the stomach and diaphragm, composed of white and red pulp; the white consists of lymphatic nodules and diffuse lymphatic tissue; the red consists of venous sinusoids between which are splenic cords; the stroma of both red and white pulp is reticular fibers and cells. A framework of fibroelastic trabeculae extending from the capsule subdivides the structure into poorly defined lobules. It is a blood-forming organ in early life and later a storage organ for red corpuscles and platelets; because of the large number of macrophages, it also acts as a blood filter, both identifying and destroying effete erythrocytes.
Synonym(s): lien [TA] , splen [TA] .
[G. splēn]

spleen

A solid, dark purplish organ, lying high on the left side of the abdomen between the stomach and the left kidney. The spleen is the largest collection of lymph tissue in the body and contains a mass of pulpy material consisting mainly of LYMPHOCYTES, PHAGOCYTES and red blood cells. The spleen is the main blood filter, removing the products of breakdown of red blood cells and other foreign and unwanted semisolid material. It is a source of lymphocytes and a major site of antibody formation.

spleen

an important part of the MONONUCLEAR PHAGOCYTE SYSTEM made up of lymphoid tissue. It stores excess red blood cells, destroys old cells, and is capable of acting as a reservoir holding 20–30% of all blood cells. It produces LYMPHOCYTES and serves to regulate the volume of blood cells elsewhere in the blood system.

Spleen

An organ located at the left side of the stomach that acts as a reservoir for blood cells and produces lymphocytes and other products involved in fighting infection.

spleen

(splēn) [TA]
Large, vascular lymphatic organ lying in upper part of abdominal cavity on left side, between stomach and diaphragm, composed of white and red pulp; blood-forming organ in early life and later a storage organ for red corpuscles and platelets.
Synonym(s): lien.
[G. splēn]
References in periodicals archive ?
Preoperative patient data included age, gender, etiology of cirrhosis, hypertension, diabetes mellitus, Child-Pugh classification, the longitudinal spleen diameter, the main portal vein diameter, spleneolus, hemoglobin levels, the PLT count, prothrombin time, and levels of total bilirubin, plasma albumin, alanine aminotransferase, blood urea nitrogen, creatinine, laminin, precollagen III, collagen IV, and hyaluronidase.
The porcine spleen perfusion model was tested as an alternative to the commonly used animal models to study the early stages of bacterial sepsis.
[17] The spleen is affected by a number of disorders.
We wanted to study the response of TKI therapy in our population (i.e south Asian, Pakistani) and association of risk factors including spleen size and WBC count at diagnosis with EMR.
As shown in Figure 2, in the spleen, gene expression of cyclin A2 (Group SP-3 d vs Group Con-3 d; Group SP-6 d vs Group Con-6 d; Group SP-9 d vs Group Con-9 d) significantly increased but p21 (Group SP-3 d relative to Group Con-3 d) and cyclin D3 (Group SP-9 d relative to Group Con-9 d) markedly decreased (p<0.05), and no significant difference was found in cyclin E2 mRNA abundance that was induced by spermine intake (p>0.05).
The spleens of the sea nomads were found to be approximately 50 per cent larger than spleens the researchers measured in other nearby indigenous people, the Saluan.
CT findings in congenital anomalies of the spleen. Br J Radiol 2001;74:767-72.
B Cells Promote the Recruitment of Neutrophils and Macrophages to the Spleen. As a major cell type in the spleen, B cells are known to produce inflammatory cytokines, including TNF[alpha].
On the contrary, spleen can be visualized in great detail through the gastric wall using EUS.
Primary angiosarcoma of the spleen. A clinico pathologic study of 40 cases.
The liver and spleen sections from all rats (n = 3 for healthy rats and n = 4 for saline- and MTX-treated rats) were fixed in 4% neutral buffered paraformaldehyde for 24 h before embedding in paraffin wax.
We present an alternative surgical approach for spleen preserving laparoscopic distal pancreatectomy which simplifies the preservation of the splenic blood supply, requires lesser mobilizations, and reduces the operating time.