endocrine pancreas

WordNet

1. of or belonging to endocrine glands or their secretions; "endocrine system" (同)endocrinal
2. a large elongated exocrine gland located behind the stomach; secretes pancreatic juice and insulin

PrepTutorEJDIC

1. 内分泌(ぶんぴつ)の / 内分泌物;内分泌腺(せん)
2. 膵臓(すいぞう)

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/07/25 10:45:24」(JST)

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Not to be confused with Langerhans cells, found in the epidermis.

Islets of Langerhans
Islet of Langerhans (mouse) in its typical proximity to a blood vessel; insulin in red, nuclei in blue.
Islets of Langerhans, the lighter tissue among the darker, acinar pancreatic tissue, hemalum-eosin stain.
Details
Latin	insulae pancreaticae
Identifiers
TA	A05.9.01.019
FMA	16016 76489, 16016
Anatomical terminology

This photograph shows a mouse pancreatic islet, an often spherical group of hormone-producing cells. Insulin is labelled here in green, glucagon in red, and the nuclei in blue.

The diagram shows the structural differences between rat islets (top) and humans islets (bottom) as well as the ventral part (left) and the dorsal part (right) of the pancreas. Different cell types are colour-coded. Rodent islets, unlike the human ones, show the characteristic insulin core.

A porcine islet of Langerhans. The left image is a brightfield image created using hematoxylin stain; nuclei are dark circles and the acinar pancreatic tissue is darker than the islet tissue. The right image is the same section stained by immunofluorescence against insulin, indicating beta cells.

Illustration depicting pancreatic islet

The islets of Langerhans are the regions of the pancreas that contain its endocrine (i.e., hormone-producing) cells. Discovered in 1869 by German pathological anatomist Paul Langerhans, the islets of Langerhans constitute approximately 1% to 2% of the mass of the pancreas.

Structure

There are about one million islets distributed throughout the pancreas of a healthy adult human,^:914 each of which measures about 0.2 mm in diameter.^:914 Each is separated from the surrounding pancreatic tissue by a thin fibrous connective tissue capsule which is continuous with the fibrous connective tissue that is interwoven throughout the rest of the pancreas.^:914 The combined mass of the islets is 1 to 1.5 grams.

Histology

Hormones produced in the islets of Langerhans are secreted directly into the blood flow by (at least) five types of cells. In rat islets, endocrine cell subsets are distributed as follows:

• Alpha cells producing glucagon (15–20% of total islet cells)
• Beta cells producing insulin and amylin (65–80%)
• Delta cells producing somatostatin (3–10%)
• PP cells (gamma cells) producing pancreatic polypeptide (3–5%)
• Epsilon cells producing ghrelin (<1%)

It has been recognized that the cytoarchitecture of pancreatic islets differs between species. In particular, while rodent islets are characterized by a predominant proportion of insulin-producing beta cells in the core of the cluster and by scarce alpha, delta and PP cells in the periphery, human islets display alpha and beta cells in close relationship with each other throughout the cluster.

Islets can influence each other through paracrine and autocrine communication, and beta cells are coupled electrically to other beta cells (but not to other cell types).

Function

The paracrine feedback system of the islets of Langerhans has the following structure:

• Glucose/Insulin: activates beta cells and inhibits alpha cells
• Glycogen/Glucagon: activates alpha cells which activates beta cells and delta cells
• Somatostatin: inhibits alpha cells and beta cells

A large number of G protein-coupled receptors (GPCRs) regulates the secretion of insulin, glucagon and somatostatin from pancreatic islets, and some of these GPCRs are the targets of drugs used to treat type-2 diabetes (ref GLP-1 receptor agonists, DPPIV inhibitors).

Electrical activity

Electrical activity of pancreatic islets has been studied using patch clamp techniques. It has turned out that the behavior of cells in intact islets differs significantly from the behavior of dispersed cells.

Clinical significance

Diabetes

The islets of Langerhans contain beta cells, which secrete insulin, and play a significant role in diabetes. It is thought that they are destroyed by immune assaults. However, there are also indications that beta cells have not been destroyed but have only become non-functional.

Transplantation

Restoration of metabolic control via the transplantation of islets of Langerhans is an appealing approach. This can be achieved by transplantation of the pancreas as vascularized organ or of isolated pancreatic islets (islet cell clusters). Islet transplantation has emerged as a viable option for the treatment of insulin requiring diabetes in the early 1970s with steady progress over the last three decades.

Islet transplantation has the possibility of restoring beta cell function from diabetes, offering an alternative to a complete pancreas transplantation or an artificial pancreas.

Because the beta cells in the islets of Langerhans are selectively destroyed by an autoimmune process in type 1 diabetes, clinicians and researchers are actively pursuing islet transplantation as a means of restoring physiological beta cell function in patients with type 1 diabetes.

Recent clinical trials have shown that insulin independence and improved metabolic control can be reproducibly obtained after transplantation of cadaveric donor islets into patients with unstable type 1 diabetes.

Islet transplantation for type 1 diabetes currently requires potent immunosuppression to prevent host rejection of donor islets.

An alternative source of beta cells, such insulin-producing cells derived from adult stem cells or progenitor cells would contribute to overcoming the shortage of donor organs for transplantation. The field of regenerative medicine is rapidly evolving and offers great hope for the nearest future. However, type 1 diabetes is the result of the autoimmune destruction of beta cells in the pancreas. Therefore, an effective cure will require a sequential, integrated approach that combines adequate and safe immune interventions with beta cell regenerative approaches.

Another potential source of beta cells may be xenotransplantation. The most likely source for xenogeneic islets for transplantation into human under evaluation is the pig pancreas. Interestingly, human and porcine insulin differ only for one amino acid, and insulin extracted from porcine pancreata has been used for the treatment of patients with diabetes before the development of recombinant human insulin technology. Several studies in small and large animals models have shown that transplantation of islet cells across species is possible. However, several problems need to be overcome for porcine islet transplantation to become a viable clinical option. The immunogenicity of xenogeneic tissues may be different from and even stronger than allogeneic tissues. For instance, Galalpha1-3Galbeta1-4GlcNAc (alpha galactosidase, alpha-Gal) expressed on porcine cells represents a major barrier to xenotransplantation being the target of preformed antibodies present in human blood.

Remarkable progress has been recorded in the development of genetically modified pigs lacking or overexpressing molecules that may improve acceptance of transplanted tissues across into humans. Pigs lacking alpha-Gal or overexpressing human decay accelerating factor (hDAF), amongst others, have been generated to study the impact on transplanted outcome in nonhuman primate models. Another possible antigenic target is the Hanganutziu-Deichter antigen, a sialic acid found in pigs and not humans, which may contribute to immunogenicity of porcine islets. Another limitation is the risk for transmission of zoonotic infections from pigs to humans, particularly from porcine endogenous retro-viruses (PERV). Amongst the approaches proposed to overcome islet xenorejection is immunoisolation of the clusters using encapsulation techniques that may shield them from immune attack. Studies in rodents and large animals have shown great promise that justify cautious optimism for the near future. Nonrandomized, uncontrolled pilot clinical trials are ongoing in subject with insulin-requiring diabetes to test the efficacy of encapsulation techniques to protect xenogeneic islets in the absence of chronic anti-rejection drugs.

Gallery

• Hormones/islet architecture
• Mouse islet immunostained for pancreatic polypeptide

• Mouse islet immunostained for insulin

• Mouse islet immunostained for glucagon

• Illustration of dog pancreas. 250x.

See also

• Betatrophin
• Human anatomy
• Pancreatic hormone
• Neuroendocrine tumor

References

External links

• "The Islets of Langerhans", Karolinska Institutet, Sweden
• "Islets"
• Islet Society
• MeSH A03.734.414
• "Pancreas, human – H&E", Blue Histology – Accessory Digestive Glands, School of Anatomy and Human Biology,

UpToDate Contents

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• 1. 膵神経内分泌腫瘍（膵島細胞腫瘍）の分類、疫学、臨床症状、局在、および病期分類 classification epidemiology clinical presentation localization and staging of pancreatic neuroendocrine tumors islet cell tumors
• 2. 膵嚢胞の分類 classification of pancreatic cysts
• 3. 膵管内乳頭粘液性腫瘍（IPMN）：病態生理および臨床症状 intraductal papillary mucinous neoplasm of the pancreas ipmn pathophysiology and clinical manifestations
• 4. 転移性膵神経内分泌腫瘍および低分化胃腸膵管神経内分泌腫瘍：腫瘍増殖をコントローするための全身療法およびホルモン分泌過剰の症状 metastatic pancreatic neuroendocrine tumors and poorly differentiated gastroenteropancreatic neuroendocrine carcinomas systemic therapy options to control tumor growth and symptoms of hormone hypersecretion
• 5. 転移性の胃腸膵管系神経内分泌腫瘍：腫瘍増殖およびホルモン過剰分泌による症状を管理するための局所治療の選択肢 metastatic gastroenteropancreatic neuroendocrine tumors local options to control tumor growth and symptoms of hormone hypersecretion

English Journal

• Exocrine cell-derived microparticles in response to lipopolysaccharide promote endocrine dysfunction in cystic fibrosis.

• Constantinescu AA1, Gleizes C2, Alhosin M3, Yala E2, Zobairi F2, Leclercq A4, Stoian G5, Mitrea IL6, Prévost G7, Toti F8, Kessler L9.Author information 1EA7293, Vascular and Tissular Stress in Transplantation, Federation of Translational Medicine of Strasbourg, Faculty of Medicine, University of Strasbourg, 74 route du Rhin, F-67401 Illkirch, Strasbourg, France; Department of Parasitology and Parasitic Diseases and Animal Biology, Faculty of Veterinary Medicine, University of Agronomical Sciences and Veterinary Medicine, 105 spl. Independentei, sector 5, 050097 Bucharest, Romania.2EA7293, Vascular and Tissular Stress in Transplantation, Federation of Translational Medicine of Strasbourg, Faculty of Medicine, University of Strasbourg, 74 route du Rhin, F-67401 Illkirch, Strasbourg, France.3UMR7213 CNRS, Laboratory of Biophotonics and Pharmacology, 74 route du Rhin, F-67401 Illkirch, France.4Department of Pneumology, University Hospital, 1 place de L'hôpital, CHU de Strasbourg, BP426, 67091 Strasbourg Cedex, France.5Department of Biochemistry and Molecular Biology, Faculty of Biology, University of Bucharest, 91-95 spl. Independentei, sector 5, 050095 Bucharest, Romania.6Department of Parasitology and Parasitic Diseases and Animal Biology, Faculty of Veterinary Medicine, University of Agronomical Sciences and Veterinary Medicine, 105 spl. Independentei, sector 5, 050097 Bucharest, Romania.7EA7290 Early Bacterial Virulence, Faculty of Medicine, University of Strasbourg, 3 rue Koeberlé, F-67000 Strasbourg, France.8UMR7213 CNRS, Laboratory of Biophotonics and Pharmacology, 74 route du Rhin, F-67401 Illkirch, France; Faculty of Pharmacy, University of Strasbourg, 74 route du Rhin, F-67401 Illkirch, France.9EA7293, Vascular and Tissular Stress in Transplantation, Federation of Translational Medicine of Strasbourg, Faculty of Medicine, University of Strasbourg, 74 route du Rhin, F-67401 Illkirch, Strasbourg, France; Department of Diabetology, University Hospital, 1 place de l'Hôpital, CHU de Strasbourg, BP421, 67091 Strasbourg Cedex, France. Electronic address: kesslerl@unistra.fr.AbstractBACKGROUND: Diabetes in cystic fibrosis (CF) is a result of exocrine pancreas alteration followed by endocrine dysfunction at a later stage. Microparticles (MPs) are plasma membrane fragments shed from stimulated or damaged cells that act as cellular effectors. Our aim was to identify a new form of interaction between exocrine and endocrine pancreatic cells mediated by exocrine MPs, in the context of recurrent infection in CF.
• Journal of cystic fibrosis : official journal of the European Cystic Fibrosis Society.J Cyst Fibros.2014 Mar;13(2):219-26. doi: 10.1016/j.jcf.2013.08.012. Epub 2013 Oct 2.
• BACKGROUND: Diabetes in cystic fibrosis (CF) is a result of exocrine pancreas alteration followed by endocrine dysfunction at a later stage. Microparticles (MPs) are plasma membrane fragments shed from stimulated or damaged cells that act as cellular effectors. Our aim was to identify a new form of
• PMID 24095207

• Role of metabotropic glutamate receptors in the regulation of pancreatic functions.

• Babic T1, Travagli RA2.Author information 1Neural and Behavioral Sciences Penn State College of Medicine, Department of Neural and Behavioral Sciences, 500 University Drive-MC H109 Hershey, PA 17033-0850, USA. Electronic address: tub13@psu.edu.2Neural and Behavioral Sciences Penn State College of Medicine, Department of Neural and Behavioral Sciences, 500 University Drive-MC H109 Hershey, PA 17033-0850, USA.AbstractThe pancreas consists of two major divisions, the exocrine and the endocrine pancreas. Recent data from our laboratory have shown that the functions of the two divisions are under modulatory regulation by separate neurocircuits that originate in the dorsal motor nucleus of the vagus (DMV). Metabotropic glutamate receptors (mGluRs) are expressed throughout the central nervous system and have been implicated in the modulation of synaptic transmission. mGluRs consist of three groups of receptors, which can be distinguished based on their pharmacological properties and second messenger systems. Group I mGluRs predominantly increase, whereas group II and III mGluRs decrease synaptic transmission. Group II and group III mGluRs are present on excitatory and inhibitory synaptic terminals impinging on pancreas-projecting DMV neurons. We have shown that group II mGluRs regulate both exocrine pancreatic secretions and insulin release, whereas group III mGluRs only regulate insulin release. Several mGluR agonists and antagonists have been shown to have clinical uses for disorders accompanied by abnormal synaptic transmission, including anxiety and Parkinson's disease. Moreover, a negative allosteric modulator of Group I mGluRs is effective in alleviating symptoms of gastro-esophageal reflux disease (GERD). Since the role of the three mGluR groups in mediating different gastrointestinal (GI) functions appears to be highly specific, the use of agonists or antagonists directed at a single receptor group could potentially provide highly selective targets for the treatment of GI disorders including GERD, functional dyspepsia and acute pancreatitis.
• Biochemical pharmacology.Biochem Pharmacol.2014 Feb 15;87(4):535-42. doi: 10.1016/j.bcp.2013.12.001. Epub 2013 Dec 16.
• The pancreas consists of two major divisions, the exocrine and the endocrine pancreas. Recent data from our laboratory have shown that the functions of the two divisions are under modulatory regulation by separate neurocircuits that originate in the dorsal motor nucleus of the vagus (DMV). Metabotro
• PMID 24355565

Japanese Journal

• 膵外分泌部異形成増加およびグルカゴン産生神経内分泌腫瘍の可能性を伴う症例でのインクレチン療法による膵内分泌部と外分泌部の著しい増殖

• Butler Alexandra E.,Campbell-Thompson Martha,Gurlo Tatyana [他]
• Diabetes : a journal of the American Diabetes Association 7(2), 25-33, 2014-03
• NAID 40020037960

• 高輝度膵の臨床的意義に関する検討 : メタボリックシンドローム,インスリン抵抗性,血清アミラーゼおよび血清エラスターゼⅠ,膵内分泌機能との関連について

• 篠田 和子,大黒 慶子,住谷 哲 [他]
• 人間ドック = Ningen Dock : official journal of the Japanese Society of Human Dry Dock 28(4), 635-640, 2013-12
• NAID 40019935129

Related Links

• endocrine pancreas - definition of endocrine pancreas by ...

pancreas a large, elongated, racemose gland located in the anterior abdomen between the liver, kidneys, stomach, spleen and duodenum. The pancreas is composed of both exocrine and endocrine tissue. The acini secrete digestive ...

• Endocrine Pancreas - arbl.cvmbs.colostate.edu

The pancreas houses two distinctly different tissues. The bulk of its mass is exocrine tissue and associated ducts, which produce an alkaline fluid loaded with digestive enzymes which is delivered to the small intestine to facilitate ...

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★リンクテーブル★

リンク元	「islet cell」「膵内分泌部」
拡張検索	「bedside-type artificial endocrine pancreas」
関連記事	「endocrine」

「islet cell」

　　[★]

島細胞

関

endocrine pancreas、islets of Langerhans、pancreatic islet

同

islet cell, regeneration of

「膵内分泌部」

　　[★]

英

endocrine pancreas

関

島細胞、ランゲルハンス島、膵島

「bedside-type artificial endocrine pancreas」

　　[★] ベッドサイド型人工膵島

「endocrine」

　　[★]

• n.

• 内分泌、エンドクリン

関

endocrinic, endocrinal