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{{Short description|Organ of the digestive system and endocrine system of vertebrates}}
{{Other uses}}
{{Good article}}
{{Infobox anatomy
| Name        = Pancreas
| Latin       = pancreas
| Greek       = πάγκρεας (pánkreas)
| Image       = Blausen_0699_PancreasAnatomy2.png
| Caption     = Anatomy of the human pancreas
| Width       =
| Precursor   = [[Pancreatic bud]]s
| System      = [[Digestion|Digestive system]] and [[endocrine system]]
| Artery      = [[Inferior pancreaticoduodenal artery]], [[anterior superior pancreaticoduodenal artery]], [[posterior superior pancreaticoduodenal artery]], [[splenic artery]]
| Vein        = [[Pancreaticoduodenal veins]], [[pancreatic veins]]
| Nerve       = [[Pancreatic plexus]], [[celiac ganglia]], [[vagus nerve]]<ref>{{cite book| title= Essentials of Human Physiology| first= Thomas M. |last= Nosek| chapter=Section 6/6ch2/s6ch2_30 |chapter-url=http://humanphysiology.tuars.com/program/section6/6ch2/s6ch2_30.htm |archive-url=https://web.archive.org/web/20160324124828/http://humanphysiology.tuars.com/program/section6/6ch2/s6ch2_30.htm|archive-date=2016-03-24}}</ref>
| Lymph       = [[Splenic lymph nodes]], [[celiac lymph nodes]] and [[superior mesenteric lymph nodes]]
| Pronunciation = {{IPAc-en|ˈ|p|æ|ŋ|k|r|i|ə|s}}
}}

The '''pancreas''' (plural '''pancreases''', or '''pancreata''') is an [[Organ (anatomy)|organ]] of the [[Digestion|digestive system]] and [[endocrine system]] of [[vertebrate]]s. In humans, it is located in the [[abdominal cavity|abdomen]] behind the [[stomach]] and functions as a [[gland]]. The pancreas is a mixed or [[heterocrine gland]], i.e., it has both an [[endocrine]] and a digestive [[exocrine]] function.<ref>{{Cite journal|last1=Gyr|first1=K.|last2=Beglinger|first2=C.|last3=Stalder|first3=G. A.|date=1985-09-21|title=[Interaction of the endo- and exocrine pancreas]|journal=Schweizerische Medizinische Wochenschrift|volume=115|issue=38|pages=1299–1306|issn=0036-7672|pmid=2865807}}</ref> Ninety-nine percent of the pancreas is exocrine and 1% is endocrine.<ref>{{Cite web|title=Pancreas Gland - Endocrine System|url=https://www.innerbody.com/image/endo03.html|access-date=2021-06-12|website=Innerbody|language=en}}</ref>{{sfn|Beger's|2018|pp=124}}<ref>{{cite book |doi=10.1016/B978-0-12-801238-3.64325-8 |chapter=Toxic Effects of Common Environmental Pollutants in Pancreatic β-Cells and the Onset of Diabetes Mellitus |title=Encyclopedia of Endocrine Diseases |date=2019 |last1=Alonso-Magdalena |first1=Paloma |last2=Tudurí |first2=Eva |last3=Marroquí |first3=Laura |last4=Quesada |first4=Ivan |last5=Sargis |first5=Robert M. |last6=Nadal |first6=Angel |pages=764–775 |isbn=978-0-12-812200-6 }}</ref><ref>{{cite journal |last1=Henderson |first1=J R |last2=Daniel |first2=P M |last3=Fraser |first3=P A |title=The pancreas as a single organ: the influence of the endocrine upon the exocrine part of the gland. |journal=Gut |date=February 1981 |volume=22 |issue=2 |pages=158–167 |doi=10.1136/gut.22.2.158 |pmc=1419227 |pmid=6111521 }}</ref> As an [[endocrine gland]], it functions mostly to regulate [[blood sugar level]]s, secreting the [[hormone]]s [[insulin]], [[glucagon]], [[somatostatin]] and [[pancreatic polypeptide]]. As a part of the digestive system, it functions as an [[exocrine gland]] secreting [[pancreatic juice]] into the [[duodenum]] through the [[pancreatic duct]]. This juice contains [[bicarbonate]], which neutralizes [[acid]] entering the duodenum from the stomach; and [[digestive enzyme]]s, which break down [[carbohydrates]], [[protein]]s and [[lipids|fats]] in food entering the duodenum from the stomach.

Inflammation of the pancreas is known as [[pancreatitis]], with common causes including chronic [[Alcohol (drug)|alcohol]] use and [[gallstone]]s. Because of its role in the regulation of blood sugar, the pancreas is also a key organ in [[diabetes]]. [[Pancreatic cancer]] can arise following [[chronic pancreatitis]] or due to other reasons, and carries a very poor prognosis, as it is often only identified after it has spread to other areas of the body.

The word pancreas comes from the [[Greek language|Greek]] πᾶν (pân, "all") & κρέας (kréas, "flesh"). The function of the pancreas in diabetes has been known since at least 1889, with its role in insulin production identified in 1921.

== Structure  ==
[[File:Pancreas and nearby organs.jpg|thumb|The pancreas (shown here in pink) sits behind the [[stomach]], with the body near the curvature of the [[duodenum]], and the tail stretching to touch the [[spleen]].]]

The pancreas is an organ that in humans lies in the [[abdomen]], stretching from behind the [[stomach]] to the left upper abdomen near the [[spleen]]. In adults, it is about {{convert|12|-|15|cm}} long, {{wt|en|lobulated}}, and salmon-coloured in appearance.{{sfn|Gray's|2016|pp=1179–1189}}

Anatomically, the pancreas is divided into a ''head'', ''neck'', ''body'', and ''tail''. The pancreas stretches from the inner curvature of the duodenum, where the head surrounds two [[blood vessel]]s: the [[superior mesenteric artery]] and [[superior mesenteric vein|vein]]. The longest part of the pancreas, the body, stretches across behind the stomach, and the tail of the pancreas ends adjacent to the [[spleen]].{{sfn|Gray's|2016|pp=1179–1189}}

Two ducts, the [[main pancreatic duct]] and a smaller [[accessory pancreatic duct]] run through the body of the pancreas. The main pancreatic duct joins with the [[common bile duct]] forming a small ballooning called the [[ampulla of Vater]] (hepatopancreatic ampulla). This ampulla is surrounded by a muscle, the [[sphincter of Oddi]]. This ampulla opens into the descending part of the [[duodenum]]. The opening of the [[common bile duct]] into [[Pancreatic duct|main pancreatic duct]] is controlled by [[sphincter of Boyden]]. The [[accessory pancreatic duct]] opens into [[duodenum]] with separate openings located above the opening of the [[Pancreatic duct|main pancreatic duct]].{{sfn|Gray's|2016|pp=1179–1189}}

===Parts===
The '''head of the pancreas''' sits within the curvature of the duodenum, and wraps around the superior mesenteric artery and vein. To the right sits the descending part of the duodenum, and between these travel the [[superior pancreaticoduodenal artery|superior]] and [[inferior pancreaticoduodenal artery|inferior pancreaticoduodenal arteries]]. Behind rest the [[inferior vena cava]], and the [[common bile duct]]. In front sit the [[peritoneum|peritoneal membrane]] and the [[transverse colon]].{{sfn|Gray's|2016|pp=1179–1189}} A small [[uncinate process of pancreas|uncinate process]] emerges from below the head, situated behind the [[superior mesenteric vein]] and sometimes [[superior mesenteric artery|artery]].{{sfn|Gray's|2016|pp=1179–1189}} A '''pancreatic notch''' is a separation between the neck of pancreas and the uncinate process.

The '''neck of the pancreas''' separates the head of the pancreas, located in the curvature of the duodenum, from the body. The neck is about {{convert|2|cm|abbr=on}} wide, and sits in front of where the [[portal vein]] is formed. The neck lies mostly behind the pylorus of the stomach, and is covered with peritoneum. The [[anterior superior pancreaticoduodenal artery]] travels in front of the neck of the pancreas.{{sfn|Gray's|2016|pp=1179–1189}}

The '''body of the pancreas''' is the largest part of the pancreas, and mostly lies behind the stomach, tapering along its length. The peritoneum sits on top of the body of the pancreas, and the [[transverse colon]] in front of the peritoneum.{{sfn|Gray's|2016|pp=1179–1189}} Behind the pancreas are several blood vessels, including the [[aorta]], the [[splenic vein]], and the [[left renal vein]], as well as the beginning of the [[superior mesenteric artery]].{{sfn|Gray's|2016|pp=1179–1189}} Below the body of the pancreas sits some of the [[small intestine]], specifically the last part of the duodenum and the [[jejunum]] to which it connects, as well as the [[suspensory ligament of the duodenum]] which falls between these two. In front of the pancreas sits the transverse colon.{{sfn|Gray's|2008|pp=1183-1190}}

The pancreas narrows towards the '''tail of the pancreas''', which sits near to the spleen.{{sfn|Gray's|2016|pp=1179–1189}} It is usually between {{convert|1.3|-|3.5|cm|abbr=on}} long, and sits between the layers of the [[splenorenal ligament|ligament between the spleen and the left kidney]]. The [[splenic artery]] and [[splenic vein|vein]] pass behind the body and tail of the pancreas.{{sfn|Gray's|2016|pp=1179–1189}}

===Blood supply===
The pancreas has a rich blood supply, with vessels originating as branches of both the [[coeliac artery]] and [[superior mesenteric artery]].{{sfn|Gray's|2016|pp=1179–1189}} The [[splenic artery]], the largest branch of the celiac trunk, runs along the top of the pancreas, and supplies the left part of the body and the tail of the pancreas through its pancreatic branches, the largest of which is called the [[greater pancreatic artery]].{{sfn|Gray's|2016|pp=1179–1189}} The [[superior pancreaticoduodenal artery|superior]] and [[inferior pancreaticoduodenal arteries]] run along the back and front surfaces of the head of the pancreas adjacent to the duodenum. These supply the head of the pancreas. These vessels join together ({{wt|en|anastamose}}) in the middle.{{sfn|Gray's|2016|pp=1179–1189}}

The body and neck of the pancreas drain into the [[splenic vein]], which sits behind the pancreas.{{sfn|Gray's|2016|pp=1179–1189}} The head drains into, and wraps around, the [[superior mesenteric vein|superior mesenteric]] and [[portal vein]]s, via the [[pancreaticoduodenal vein]]s.{{sfn|Gray's|2016|pp=1179–1189}}

The pancreas drains into lymphatic vessels that travel alongside its [[artery|arteries]], and has a rich lymphatic supply.{{sfn|Gray's|2016|pp=1179–1189}} The [[lymphatic vessel]]s of the body and tail drain into [[splenic lymph nodes]], and eventually into [[Preaortic lymph nodes|lymph nodes that lie in front of the aorta]], between the coeliac and superior mesenteric arteries. The lymphatic vessels of the head and neck drain into intermediate lymphatic vessels around the pancreaticoduodenal, mesenteric and hepatic arteries, and from there into the lymph nodes that lie in front of the aorta.{{sfn|Gray's|2016|pp=1179–1189}}

===Microanatomy===
[[File:Langerhanssche Insel.jpg|thumb|This image shows a [[pancreatic islet]] when pancreatic tissue is stained and viewed under a microscope. Parts of the digestive ("exocrine") pancreas can be seen around the islet, more darkly. These contain hazy dark purple granules of inactive digestive enzymes ([[zymogen]]s).]]
[[File:Human pancreatic islet.jpg|thumb|An image using [[immunohistochemistry|fluorescent antibodies]] to show the location of different cell types in the pancreatic islet. Antibodies against glucagon, secreted by alpha cells, show their peripheral position. Antibodies against insulin, secreted by beta cells, show the more widespread and central position that these cells tend to have.{{sfn|Wheater's Histology|2013|pp=332-333}} ]]
The pancreas contains tissues with both an [[endocrine]] and [[exocrine]] role. This division is visible when the pancreas is viewed under a microscope.{{sfn|Wheater's Histology|2013|pp=287-291}}

The majority of pancreatic [[Parenchyma|tissue]] has a digestive role. The cells with this role form clusters ([[acini]]) around small [[duct (anatomy)|ducts]], and are arranged in lobes that have thin [[fibrous tissue|fibrous]] walls. The cells of each acinus secrete inactive digestive enzymes called [[zymogen]]s into the small ''intercalated'' ducts which they surround. In each acinus, the cells are pyramid-shaped and situated around the intercalated ducts, with the [[Cell nucleus|nuclei]] resting on the [[basement membrane]], a large [[endoplasmic reticulum]], and a number of zymogen granules visible within the [[cytoplasm]]. The intercalated ducts drain into larger ''intralobular'' ducts within the lobule, and finally ''interlobular'' ducts. The ducts are lined by a single layer of [[columnar epithelium|column-shaped cells]]. There is more than one layer of cells as the diameter of the ducts increases.{{sfn|Wheater's Histology|2013|pp=287-291}}

The tissues with an [[endocrine]] role within the pancreas exist as clusters of cells called [[pancreatic islets]] (also called islets of [[Paul Langerhans|Langerhans]]) that are distributed throughout the pancreas.{{sfn|Wheater's Histology|2013|pp=332-333}} Pancreatic islets contain [[alpha cell]]s, [[beta cell]]s, and [[delta cell]]s, each of which releases a different hormone. These cells have characteristic positions, with alpha cells (secreting [[glucagon]]) tending to be situated around the periphery of the islet, and beta cells (secreting [[insulin]]) more numerous and found throughout the islet.{{sfn|Wheater's Histology|2013|pp=332-333}} [[Enterochromaffin cell]]s are also scattered throughout the islets.{{sfn|Wheater's Histology|2013|pp=332-333}} Islets are composed of up to 3,000 secretory cells, and contain several small arterioles to receive blood, and venules that allow the hormones secreted by the cells to enter the [[systemic circulation]].{{sfn|Wheater's Histology|2013|pp=332-333}}

===Variation===
The size of the pancreas varies considerably.{{sfn|Gray's|2016|pp=1179–1189}} Several [[anatomical variation]]s exist, relating to the embryological development of the two [[pancreatic bud]]s. The pancreas develops from these buds on either side of the duodenum. The [[pancreatic bud|ventral bud]] rotates to lie next to the [[pancreatic bud|dorsal bud]], eventually fusing. In about 10% of adults, an [[accessory pancreatic duct]] may be present if the main duct of the dorsal bud of the pancreas does not regress; this duct opens into the [[minor duodenal papilla]].<ref name=Langmans2019 /> If the two buds themselves, each having a duct, do not fuse, a pancreas may exist with two separate ducts, a condition known as a [[pancreas divisum]]. This condition has no physiologic consequence.<ref name="KanthMedscape">{{EMedicine|article|185307|Pancreatic Divisum}}</ref> If the ventral bud does not fully rotate, an [[annular pancreas]] may exist, where part or all of the duodenum is encircled by the pancreas. This may be associated with [[duodenal atresia]].<ref name="Noh2012">{{cite journal |last1=Noh |first1=TH |last2=Lee |first2=SE |last3=Park |first3=JM |title=Laparoscopic treatment of annular pancreas in adults: report of a case. |journal=Korean Journal of Hepato-biliary-pancreatic Surgery |date=February 2012 |volume=16 |issue=1 |pages=43–5 |doi=10.14701/kjhbps.2012.16.1.43 |pmid=26388905|pmc=4575014 }}</ref>

=== Gene and protein expression ===
{{Further |Bioinformatics#Gene and protein expression}}
10,000 protein coding genes (~50% of all human genes) are expressed in the normal human pancreas.<ref>{{Cite web|url=https://www.proteinatlas.org/humanproteome/pancreas|title=The human proteome in pancreas – The Human Protein Atlas|website=www.proteinatlas.org|access-date=2017-09-25}}</ref><ref>{{cite journal | vauthors = Uhlén M, Fagerberg L, Hallström BM, Lindskog C, Oksvold P, Mardinoglu A, Sivertsson Å, Kampf C, Sjöstedt E, Asplund A, Olsson I, Edlund K, Lundberg E, Navani S, Szigyarto CA, Odeberg J, Djureinovic D, Takanen JO, Hober S, Alm T, Edqvist PH, Berling H, Tegel H, Mulder J, Rockberg J, Nilsson P, Schwenk JM, Hamsten M, von Feilitzen K, Forsberg M, Persson L, Johansson F, Zwahlen M, von Heijne G, Nielsen J, Pontén F | display-authors = 6 | title = Proteomics. Tissue-based map of the human proteome | journal = Science | volume = 347 | issue = 6220 | article-number = 1260419 | date = January 2015 | pmid = 25613900 | doi = 10.1126/science.1260419 | s2cid = 802377 }}</ref> Less than 100 of these genes are specifically expressed in the pancreas. Similar to the [[salivary gland]]s, most pancreas-specific genes encode for secreted proteins. Corresponding pancreas-specific proteins are either expressed in the exocrine cellular compartment and have functions related to digestion or food uptake such as digestive [[chymotrypsinogen]] enzymes and pancreatic lipase [[Pancreatic lipase family|PNLIP]], or are expressed in the various cells of the endocrine [[pancreatic islets]] and have functions related to secreted hormones such as [[insulin]], [[glucagon]], [[somatostatin]] and [[pancreatic polypeptide]].<ref>{{cite journal | vauthors = Danielsson A, Pontén F, Fagerberg L, Hallström BM, Schwenk JM, Uhlén M, Korsgren O, Lindskog C | display-authors = 6 | title = The human pancreas proteome defined by transcriptomics and antibody-based profiling | journal = PLOS ONE | volume = 9 | issue = 12 | article-number = e115421 | date = 2014-12-29 | pmid = 25546435 | pmc = 4278897 | doi = 10.1371/journal.pone.0115421 | bibcode = 2014PLoSO...9k5421D | doi-access = free }}</ref>

==Development==
[[File:Suckale08FBS fig1 pancreas development.jpeg|thumbnail|300px|The pancreas originates from the [[foregut]], a precursor tube to part of the [[digestive tract]], as a [[Anatomical terms of location#Dorsal and ventral|dorsal and ventral]] bud. As it develops, the ventral bud rotates to the other side and the two buds fuse together.]]

The pancreas forms during [[Prenatal development|development]] from two [[pancreatic bud]]s that arise from the [[duodenum|duodenal]] part of the [[foregut]], an embryonic tube that is a precursor to the [[gastrointestinal tract]].<ref name=Langmans2019>{{cite book |last1=Sadley |first1=TW |title=Langman's medical embryology |date=2019|location=Philadelphia|publisher=Wolters Kluwer |isbn=978-1-4963-8390-7 |edition=14th|pages=244–245}}</ref> It is of [[endoderm]]al origin.<ref name=Langmans2019 /> Pancreatic development begins with the formation of a [[Anatomical terms of location#Dorsal and ventral|dorsal and ventral]] pancreatic bud. Each joins with the foregut through a duct. The dorsal pancreatic bud forms the neck, body, and tail of the developed pancreas, and the ventral pancreatic bud forms the head and uncinate process.<ref name=Langmans2019 />

The definitive pancreas results from rotation of the ventral bud and the fusion of the two buds.<ref name=Langmans2019 /> During development, the duodenum rotates to the right, and the ventral bud rotates with it, moving to a position that becomes more dorsal. Upon reaching its final destination, the ventral pancreatic bud is below the larger dorsal bud, and eventually fuses with it. At this point of fusion, the main ducts of the ventral and dorsal pancreatic buds fuse, forming the [[main pancreatic duct]]. Usually, the duct of the dorsal bud regresses, leaving the main pancreatic duct.<ref name=Langmans2019 />

===Cellular development===
[[Pancreatic Progenitor Cell|Pancreatic progenitor cells]] are precursor cells that differentiate into the functional pancreatic cells, including exocrine [[centroacinar cell]]s, endocrine islet cells, and ductal cells.<ref name="carlson"/> These progenitor cells are characterised by the co-expression of the [[transcription factor]]s [[PDX1]] and [[NKX6-1]].<ref name="carlson"/>

<!--Exocrine-->The cells of the exocrine pancreas differentiate through molecules that induce differentiation including [[follistatin]], [[fibroblast growth factor]]s, and activation of the [[Notch receptor]] system.<ref name="carlson">{{cite book | last = Carlson | first = Bruce M. | name-list-style = vanc |title=Human Embryology and Developmental Biology |publisher=Elsevier |location=St. Louis |year=2019 |pages=318–57 |isbn=978-0-323-52375-2 }}</ref> Development of the exocrine acini progresses through three successive stages. These are the predifferentiated, protodifferentiated, and differentiated stages, which correspond to undetectable, low, and high levels of digestive enzyme activity, respectively.<ref name="carlson"/>

<!--Endocrine-->Pancreatic progenitor cells differentiate into endocrine islet cells under the influence of [[neurogenins|neurogenin-3]] and [[ISL1]], but only in the absence of [[notch signaling pathway|notch receptor signaling]]. Under the direction of a [[Pax gene]], the endocrine precursor cells differentiate to form alpha and gamma cells. Under the direction of [[Pax-6]], the endocrine precursor cells differentiate to form beta and delta cells.<ref name="carlson"/> The pancreatic islets form as the endocrine cells migrate from the duct system to form small clusters around [[capillary|capillaries]].{{sfn|Wheater's Histology|2013|pp=332-333}} This occurs around the third month of development,<ref name=Langmans2019 /> and insulin and glucagon can be detected in the human [[fetal circulation]] by the fourth or fifth month of development.<ref name="carlson"/>

== Function ==

The pancreas is involved in [[blood sugar control]] and [[metabolism]] within the body, and also in the secretion of substances (collectively [[pancreatic juice]]) that help [[digestion]]. These functions are divided into an [[endocrine gland|endocrine]] role, relating to the secretion of [[insulin]] and other [[hormone]]s within pancreatic islets that help control blood sugar levels and metabolism, and an [[Exocrine gland|exocrine]] role, relating to the secretion of [[Pancreatic enzymes|pancreatic digestive enzymes]].{{sfn|Wheater's Histology|2013|pp=287-291}}

===Blood glucose regulation===
{{See also|Pancreatic islets}}
[[File:Negative Feedback Gif.gif|thumb|The pancreas maintains constant blood glucose levels (shown as the waving line). When the [[Blood sugar level|blood glucose level]] is too high, the pancreas secretes [[insulin]]. If the level is too low, the pancreas secretes [[glucagon]].

]]
Cells within the pancreas help to maintain blood glucose levels ([[homeostasis]]). The cells that do this are located within the pancreatic islets that are present throughout the pancreas. The following processes take place with blood glucose levels:

* When blood glucose levels are low, [[alpha cell]]s secrete [[glucagon]], which increases blood glucose levels.
* When blood glucose levels are high [[beta cell]]s secrete [[insulin]] to decrease glucose in blood. 

[[Delta cell]]s in the islet also secrete [[somatostatin]] which decreases the release of insulin and glucagon.{{sfn|Wheater's Histology|2013|pp=332-333}}

Glucagon acts to increase glucose levels by promoting the [[gluconeogenesis|creation of glucose]] and the [[glycogenolysis|breakdown of glycogen]] to glucose in the liver. It also decreases the uptake of glucose in fat and muscle. Glucagon release is stimulated by low blood glucose or insulin levels, and during exercise.{{sfn|Harrison's|2015|pp=2853-4}} Insulin acts to decrease blood glucose levels by facilitating uptake by cells (particularly [[skeletal muscle]]), and promoting its use in the creation of proteins, fats and carbohydrates. Insulin is initially created as a precursor form called [[preproinsulin]]. This is converted to [[proinsulin]] and cleaved by [[C-peptide]] to [[insulin]] which is then stored in granules in beta cells. Glucose is taken into the beta cells and degraded. The end effect of this is to cause [[depolarisation]] of the cell membrane which stimulates the release of the insulin.{{sfn|Harrison's|2015|pp=2853-4}}

<!--Influences-->The main factor influencing the secretion of insulin and glucagon are the levels of glucose in blood plasma.<ref name=Ganongs2019Islets>{{Cite book|title=Ganong's review of medical physiology|author1=Barrett, Kim E.|others=Barman, Susan M.,, Brooks, Heddwen L., Yuan, Jason X.-J.|isbn=978-1-260-12240-4|edition=26th|location=New York|oclc=1076268769|year=2019|pages=433–437|section=Regulation of Insulin Secretion; Glucagon}}</ref> Low blood sugar stimulates glucagon release, and high blood sugar stimulates insulin release. Other factors also influence the secretion of these hormones. Some [[amino acid]]s, that are byproducts of the digestion of [[protein]], stimulate insulin and glucagon release. Somatostatin acts as an inhibitor of both insulin and glucagon. The [[autonomic nervous system]] also plays a role. Activation of [[Beta-2 adrenergic receptor|Beta-2 receptors]] of the [[sympathetic nervous system]] by [[catecholamine]]s secreted from sympathetic nerves stimulates secretion of insulin and glucagon,<ref name=Ganongs2019Islets /><ref name=GuytonHall2016>{{cite book |last1=Hall |first1=John E |title=Guyton and Hall textbook of medical physiology |date=2016 |publisher=Elsevier |location=Philadelphia |isbn=978-1-4557-7016-8 |edition=13th|pages=990–994}}</ref> whereas activation of [[Alpha-1 adrenergic receptors|Alpha-1 receptors]] inhibits secretion.<ref name=Ganongs2019Islets /> [[Muscarinic acetylcholine receptor M3|M3 receptors]] of the [[parasympathetic nervous system]] act when stimulated by the right [[vagus nerve]] to stimulate release of insulin from beta cells.<ref name=Ganongs2019Islets />

===Digestion===
[[File:1820 The Pancreas.jpg|thumb|The pancreas has a role in digestion, highlighted here. Ducts in the pancreas (green) conduct digestive enzymes into the duodenum. This image also shows a [[pancreatic islet]], part of the endocrine pancreas, which contains cells responsible for secretion of [[insulin]] and [[glucagon]].]]
The pancreas plays a vital role in the [[digestive system]]. It does this by secreting [[pancreatic juice]], a fluid that contains digestive enzymes, into the [[duodenum]], the first part of the [[small intestine]] that receives food from the [[stomach]]. These enzymes help to break down carbohydrates, proteins and lipids (fats). This is the [[exocrine]] role of the pancreas. The cells responsible for this are [[centroacinar cell]]s arranged in clusters called [[acini]]. Secretions into the middle of the acinus accumulate in [[intralobular ducts]], which drain to the main [[pancreatic duct]], which drains directly into the [[duodenum]]. About 1.5–3 liters of fluid are secreted in this manner every day.{{sfn|Gray's|2008|pp=1183-1190}}{{sfn|Harrison's|2015|pp=2086-2102}}

The cells in each acinus are filled with granules containing the digestive enzymes. These are secreted in an inactive form termed [[zymogen]]s or proenzymes. When released into the duodenum, they are activated by the enzyme [[enterokinase]] present in the lining of the duodenum. The proenzymes are cleaved, creating a cascade of activating enzymes.{{sfn|Harrison's|2015|pp=2086-2102}}
* [[Protease|Enzymes that break down proteins]] begin with activation of [[trypsinogen]] to [[trypsin]]. The free trypsin then cleaves the rest of the trypsinogen, as well as [[chymotrypsinogen]] to its active form [[chymotrypsin]].{{sfn|Harrison's|2015|pp=2086-2102}}
* Enzymes secreted involved in the digestion of fats include [[pancreatic lipase|lipase]], [[phospholipase A2]], [[lysophospholipase]], and [[Sterol esterase|cholesterol esterase]].{{sfn|Harrison's|2015|pp=2086-2102}}
* Enzymes that break down starch and other carbohydrates include [[amylase]].{{sfn|Harrison's|2015|pp=2086-2102}}

These enzymes are secreted in a fluid rich in [[bicarbonate]]. Bicarbonate helps maintain an [[alkaline]] pH for the fluid, a pH in which most of the enzymes act most efficiently, and also helps to neutralise the stomach acids that enter the duodenum.{{sfn|Harrison's|2015|pp=2086-2102}} Secretion is influenced by hormones including [[secretin]], [[cholecystokinin]], and [[vasoactive intestinal peptide|VIP]], as well as [[acetylcholine]] stimulation from the [[vagus nerve]]. Secretin is released from the [[S cell]]s which form part of the lining of the duodenum in response to stimulation by gastric acid. Along with VIP, it increases the secretion of enzymes and bicarbonate. Cholecystokinin is released from [[Ito cell]]s of the lining of the duodenum and jejunum mostly in response to long chain fatty acids, and increases the effects of secretin.{{sfn|Harrison's|2015|pp=2086-2102}} At a cellular level, bicarbonate is secreted from centroacinar and ductal cells through a sodium and bicarbonate [[cotransporter]] that acts because of membrane depolarisation caused by the [[cystic fibrosis transmembrane conductance regulator]]. Secretin and VIP act to increase the opening of the cystic fibrosis transmembrane conductance regulator, which leads to more membrane depolarisation and more secretion of bicarbonate.{{sfn|Harrison's|2015|pp=2090}}{{sfn|Beger's|2018|pp=16,57}}<ref name="Pandol2014">{{cite journal |last1=Pandol |first1=Stephen J |title=The Exocrine Pancreas |journal=Colloquium Series on Integrated Systems Physiology: From Molecule to Function |volume=3 |issue=2 |date=2011 |pages=1–64 |id={{NCBIBook|NBK54128}} |pmid=21634067 |doi=10.4199/C00026ED1V01Y201102ISP014 |doi-access=free }}</ref>

A variety of mechanisms act to ensure that the digestive action of the pancreas does not act to digest pancreatic tissue itself. These include the secretion of inactive enzymes (zymogens), the secretion of the protective enzyme [[trypsin inhibitor]], which inactivates trypsin, the changes in pH that occur with bicarbonate secretion that stimulate digestion only when the pancreas is stimulated, and the fact that the low calcium within cells causes inactivation of trypsin.{{sfn|Harrison's|2015|pp=2086-2102}}

===Additional functions===
The pancreas also secretes [[vasoactive intestinal peptide]] and [[pancreatic polypeptide]]. [[Enterochromaffin cell]]s of the pancreas secrete the hormones [[motilin]], [[serotonin]], and [[substance P]].{{sfn|Wheater's Histology|2013|pp=332-333}} It has been demonstrated that pancreatic tissue is a strong accumulator and secretor in the intestine of radioactive cesium ([[Cs-137]]).<ref>{{Cite journal |last=Bandazhevsky Y.I. |year=2003 |title=Chronic Cs-137 incorporation in children's organs. |journal=Swiss Med. Wkly. |volume=133 |issue=35–36 |pages=488–90 |doi=10.4414/smw.2003.10226 |pmid=14652805 |s2cid=28184979 |doi-access=free}}</ref><ref>{{cite journal |last1=Venturi |first1=Sebastiano |title=Cesium in Biology, Pancreatic Cancer, and Controversy in High and Low Radiation Exposure Damage—Scientific, Environmental, Geopolitical, and Economic Aspects |journal=International Journal of Environmental Research and Public Health |date=January 2021 |volume=18 |issue=17 |page=8934 |doi=10.3390/ijerph18178934 |pmid=34501532 |language=en|pmc=8431133 |doi-access=free }}</ref>

==Clinical significance==
{{main|Pancreatic disease}}

===Inflammation===
{{Main|Pancreatitis}}
Inflammation of the pancreas is known as [[pancreatitis]]. Pancreatitis is most often associated with recurrent [[gallstone]]s or chronic alcohol use, with other common causes including traumatic damage, damage following an [[ERCP]], some medications, infections such as [[mumps]] and [[hypertriglyceridaemia|very high blood triglyceride levels]]. Acute pancreatitis is likely to cause intense pain in the central [[abdomen]], that often radiates to the back, and may be associated with nausea or vomiting. Severe pancreatitis may lead to bleeding or perforation of the pancreas resulting in [[shock (circulatory)|shock]] or a [[systemic inflammatory response syndrome]], [[Grey Turner's sign|bruising of the flanks]] or the [[Cullen's sign|region around the belly button]]. These severe complications are often managed in an [[intensive care unit]].{{sfn|Davidson's|2018|p=837-844}}

In pancreatitis, enzymes of the exocrine pancreas damage the structure and tissue of the pancreas. Detection of some of these enzymes, such as [[amylase]] and [[lipase]] in the blood, along with symptoms and findings on [[medical imaging]] such as [[ultrasound]] or a [[CT scan]], are often used to indicate that a person has pancreatitis. Pancreatitis is often managed medically with [[analgesic|pain relief]], and monitoring to prevent or manage shock, and management of any identified underlying causes. This may include removal of gallstones, lowering of blood triglyceride or glucose levels, the use of [[corticosteroid]]s for [[autoimmune pancreatitis]], and the cessation of any medication triggers.{{sfn|Davidson's|2018|p=837-844}}

[[Chronic pancreatitis]] refers to the development of pancreatitis over time. It shares many similar causes, with the most common being chronic alcohol use, with other causes including recurrent acute episodes and [[cystic fibrosis]]. Abdominal pain, characteristically relieved by sitting forward or drinking alcohol, is the most common symptom. When the digestive function of the pancreas is severely affected, this may lead to problems with fat digestion and the development of [[steatorrhoea]]; when the endocrine function is affected, this may lead to diabetes. Chronic pancreatitis is investigated in a similar way to acute pancreatitis. In addition to management of pain and nausea, and management of any identified causes (which may include [[alcohol cessation]]), because of the digestive role of the pancreas, [[enzyme replacement]] may be needed to prevent [[malabsorption]].{{sfn|Davidson's|2018|p=837-844}}

===Cancer===
{{Main|Pancreatic cancer}}
[[File:Pancreatic Cancer.jpg|thumb|Pancreatic cancer, shown here, most commonly occurs as an [[adenocarcinoma]] in the head of the pancreas. Because symptoms (such as skin yellowing, pain, or itch) do not occur until later in the disease, it often presents at a later [[Cancer staging|stage]] and has limited treatment options.]]
[[File:Relative incidence of pancreatic neoplasms.png|thumb|350px|Relative incidences of various pancreatic [[neoplasm]]s, with pancreatic cancers in red/pink color.<ref>{{cite journal |last1=Wang |first1=Y |last2=Miller |first2=FH |last3=Chen |first3=ZE |last4=Merrick |first4=L |last5=Mortele |first5=KJ |last6=Hoff |first6=FL | display-authors=etal| title=Diffusion-weighted MR imaging of solid and cystic lesions of the pancreas. | journal=Radiographics | year= 2011 | volume= 31 | issue= 3 | pages= E47-64 | pmid=21721197 | doi=10.1148/rg.313105174 | pmc= }}<br />Diagram by Mikael Häggström, M.D.</ref>]]
[[Pancreatic cancer]]s, particularly the most common type, pancreatic [[adenocarcinoma]], remain very difficult to treat, and are mostly diagnosed only at a stage that is too late for surgery, which is the only curative treatment.  Pancreatic cancer is rare in people younger than 40 and the [[median]] age of [[diagnosis]] is 71.<ref name=NEJM14>{{cite journal | vauthors = Ryan DP, Hong TS, Bardeesy N | title = Pancreatic adenocarcinoma | journal = The New England Journal of Medicine | volume = 371 | issue = 11 | pages = 1039–49 | date = September 2014 | pmid = 25207767 | doi = 10.1056/NEJMra1404198 }}</ref> Risk factors include chronic pancreatitis, older age, smoking, [[obesity]], [[diabetes mellitus|diabetes]], and certain rare genetic conditions including [[multiple endocrine neoplasia type 1]], [[hereditary nonpolyposis colon cancer]] and [[dysplastic nevus syndrome]] among others.{{sfn|Davidson's|2018|p=837-844}}<ref name=PDQ2014>{{cite web|title=Pancreatic Cancer Treatment (PDQ®) Patient Version|url=http://www.cancer.gov/cancertopics/pdq/treatment/pancreatic/Patient/page1/AllPages|website=National Cancer Institute|access-date=8 June 2014|date=2014-04-17}}</ref> About 25% of cases are attributable to [[tobacco smoking]],<ref>{{cite journal | vauthors = Wolfgang CL, Herman JM, Laheru DA, Klein AP, Erdek MA, Fishman EK, Hruban RH | title = Recent progress in pancreatic cancer | journal = CA: A Cancer Journal for Clinicians | volume = 63 | issue = 5 | pages = 318–48 | date = September 2013 | pmid = 23856911 | pmc = 3769458 | doi = 10.3322/caac.21190 }}</ref> while 5–10% of cases are linked to [[heredity|inherited genes]].<ref name="NEJM14" />

Pancreatic adenocarcinoma is the most common form of pancreatic cancer, and is cancer arising from the exocrine digestive part of the pancreas. Most occur in the head of the pancreas.{{sfn|Davidson's|2018|p=837-844}} Symptoms tend to arise late in the course of the cancer, when it causes abdominal pain, weight loss, or yellowing of the skin ([[jaundice]]). Jaundice occurs when the outflow of [[bile]] is blocked by the cancer. Other less common symptoms include nausea, vomiting, pancreatitis, diabetes or recurrent [[venous thrombosis]].{{sfn|Davidson's|2018|p=837-844}} Pancreatic cancer is usually diagnosed by [[medical imaging]] in the form of an [[ultrasound]] or [[CT scan]] with contrast enhancement. An [[endoscopic ultrasound]] may be used if a tumour is being considered for surgical removal, and biopsy guided by [[ERCP]] or ultrasound can be used to confirm an uncertain diagnosis.{{sfn|Davidson's|2018|p=837-844}}

Because of the late development of symptoms, most cancer presents at an advanced [[Cancer staging|stage]].{{sfn|Davidson's|2018|p=837-844}} Only 10 to 15% of tumours are suitable for surgical resection.{{sfn|Davidson's|2018|p=837-844}} {{As of|2018}}, when chemotherapy is given the [[FOLFIRINOX]] regimen containing [[fluorouracil]], [[irinotecan]], [[oxaliplatin]] and [[leucovorin]] has been shown to extend survival beyond traditional [[gemcitabine]] regimens.{{sfn|Davidson's|2018|p=837-844}} For the most part, treatment is [[palliative]], focus on the management of symptoms that develop. This may include management of [[itch]], a [[Bile duct#Drainage|choledochojejunostomy]] or the insertion of stents with [[ERCP]] to facilitate the drainage of bile, and medications to help control pain.{{sfn|Davidson's|2018|p=837-844}} In the United States pancreatic cancer is the fourth most common cause of deaths due to cancer.<ref name="PMC2504856">{{cite journal | vauthors = Hariharan D, Saied A, Kocher HM | title = Analysis of mortality rates for pancreatic cancer across the world | journal = HPB | volume = 10 | issue = 1 | pages = 58–62 | year = 2008 | pmid = 18695761 | pmc = 2504856 | doi = 10.1080/13651820701883148 }}</ref> The disease occurs more often in the developed world, which had 68% of new cases in 2012.<ref name=WCR2014>{{cite book|title=World Cancer Report 2014|date=2014|publisher=World Health Organization|isbn=978-92-832-0429-9|chapter=Chapter 5.7}}</ref> Pancreatic adenocarcinoma typically has poor outcomes with the average percentage alive for at least one and five years after [[diagnosis]] being 25% and 5% respectively.<ref name=WCR2014/><ref name="ACS-CFF-2010">{{cite web| title=American Cancer Society: Cancer Facts & Figures 2010: see page 4 for incidence estimates, and page 19 for survival percentages| url=http://www.cancer.org/acs/groups/content/@nho/documents/document/acspc-024113.pdf| archive-url=https://web.archive.org/web/20150114080100/http://www.cancer.org/acs/groups/content/%40nho/documents/document/acspc-024113.pdf| archive-date=2015-01-14}}</ref> In localized disease where the cancer is small (< 2&nbsp;cm) the number alive at five years is approximately 20%.<ref name=PDQ2014P>{{cite web|title=Pancreatic Cancer Treatment (PDQ®) Health Professional Version|url=http://www.cancer.gov/cancertopics/pdq/treatment/pancreatic/HealthProfessional/page1/AllPages|website=NCI|access-date=8 June 2014|date=2014-02-21}}</ref>

There are several types of pancreatic cancer, involving both the endocrine and exocrine tissue. The many types of [[pancreatic endocrine tumor]]s are all uncommon or rare, and have varied outlooks.  However the [[Incidence (epidemiology)|incidence]] of these cancers has been rising sharply; it is not clear to what extent this reflects increased detection, especially through [[medical imaging]], of tumors that would be very slow to develop. [[Insulinoma]]s (largely benign) and [[gastrinoma]]s are the most common types.<ref>{{cite journal | vauthors = Burns WR, Edil BH | title = Neuroendocrine pancreatic tumors: guidelines for management and update | journal = Current Treatment Options in Oncology | volume = 13 | issue = 1 | pages = 24–34 | date = March 2012 | pmid = 22198808 | doi = 10.1007/s11864-011-0172-2 | s2cid = 7329783 }}</ref>  For those with neuroendocrine cancers the number alive after five years is much better at 65%, varying considerably with type.<ref name=WCR2014/>

A [[solid pseudopapillary tumour]] is a low-grade malignant tumour of the pancreas of [[:wikt:papilla|papillary]] architecture that typically afflicts young women.<ref>{{cite journal | vauthors = Patil TB, Shrikhande SV, Kanhere HA, Saoji RR, Ramadwar MR, Shukla PJ | title = Solid pseudopapillary neoplasm of the pancreas: a single institution experience of 14 cases |doi-access=free | journal = HPB | volume = 8 | issue = 2 | pages = 148–50 | year = 2006 | pmid = 18333264 | pmc = 2131425 | doi = 10.1080/13651820510035721 }}</ref>

===Diabetes mellitus===
====Type 1 diabetes====
{{Main|Diabetes mellitus type 1}}
[[Diabetes mellitus type 1]] is a chronic [[autoimmune disease]] in which the [[immune system]] attacks the insulin-secreting beta cells of the pancreas.<ref name=Ganongs2019DM>{{Cite book|title=Ganong's review of medical physiology|publisher=McGraw-Hill Education |first1=Kim E. |last1=Barrett |first2=Susan M. |last2=Barman |first3=Heddwen L. |last3=Brooks |first4=Jason X.-J. |last4=Yuan |first5=William F. |last5=Ganong |isbn=978-1-260-12240-4|edition=26th|location=New York|oclc=1076268769|year=2019|pages=440–441|section=Hypoglycaemia & Diabetes Mellitus in Humans}}</ref> Insulin is needed to keep [[blood sugar]] levels within optimal ranges, and its lack can lead to [[hyperglycemia|high blood sugar]]. As an untreated chronic condition, complications including accelerated [[vascular disease]], [[diabetic retinopathy]], [[diabetic nephropathy|kidney disease]] and [[diabetic neuropathy|neuropathy]] can result.<ref name=Ganongs2019DM /> In addition, if there is not enough insulin for glucose to be used within cells, the medical emergency [[diabetic ketoacidosis]], which is often the first symptom that a person with type 1 diabetes may have, can result.{{sfn|Davidson's|2018|p=735}} Type 1 diabetes can develop at any age but is most often diagnosed before age 40.<ref name=Ganongs2019DM /> For people living with type 1 diabetes, insulin injections are critical for survival.<ref name=Ganongs2019DM /> An experimental procedure to treat type 1 diabetes is [[pancreas transplantation]] or isolated [[islet cell transplantation|transplantation of islet cells]] to supply a person with functioning beta cells.<ref name=Ganongs2019DM />

====Type 2 diabetes====
{{Main|Diabetes mellitus type 2}}
Diabetes mellitus type 2 is the most common form of diabetes.<ref name=Ganongs2019DM /> The causes for high blood sugar in this form of diabetes usually are a combination of [[insulin resistance]] and impaired insulin secretion, with both genetic and environmental factors playing a role in the development of the disease.{{sfn|Davidson's|2018|p=730-732}} Over time, pancreatic beta cells may become "exhausted" and less functional.<ref name=Ganongs2019DM /> The management of type 2 diabetes involves a combination of lifestyle measures, medications if required and potentially [[insulin (medication)|insulin]].{{sfn|Davidson's|2018|p=745-751}} 
With relevance to the pancreas, several medications act to enhance the secretion of insulin from beta cells, particularly [[sulphonylurea]]s, which act directly on beta cells; [[incretins]] which replicate the action of the hormones [[glucagon-like peptide 1]], increasing the secretion of insulin from beta cells after meals, and are more resistant to breakdown; and [[DPP-4 inhibitors]], which slow the breakdown of incretins.{{sfn|Davidson's|2018|p=745-751}}

===Removal===
It is possible for a person to live without a pancreas, provided that the person takes insulin for proper regulation of blood glucose concentration and [[Pancreatic enzymes (medication)|pancreatic enzyme supplements]] to aid digestion.<ref name=banks>{{cite journal | vauthors = Banks PA, Conwell DL, Toskes PP | title = The management of acute and chronic pancreatitis | journal = Gastroenterology & Hepatology | volume = 6 | issue = 2 Suppl 3 | pages = 1–16 | date = February 2010 | pmid = 20567557 | pmc = 2886461 }}</ref>

==History==
The pancreas was first identified by [[Herophilus]] (335–280 BC), a [[Greeks|Greek]] [[anatomist]] and [[surgery|surgeon]].<ref>{{Cite book | title = History of the Pancreas: Mysteries of a Hidden Organ | last1 = Howard | first1 = John M. | last2 = Hess | first2 = Walter | name-list-style = vanc | date = 2012 | publisher = Springer Science & Business Media | isbn = 978-1-4615-0555-6 | page = 24 | language = en }}</ref> A few hundred years later, [[Rufus of Ephesus]], another Greek anatomist, gave the pancreas its name. Etymologically, the term "pancreas", a modern [[Latin]] adaptation of [[Greek language|Greek]] πάγκρεας,<ref name="O'Brien">{{cite book| first = Terry | last = O'Brien | name-list-style = vanc |title=A2Z Book of word Origins|url=https://books.google.com/books?id=Rgzh83cChl0C&pg=PT86|publisher=Rupa Publications|isbn=978-81-291-1809-7|page=86|year=2015}}</ref> [πᾶν ("all", "whole"), and κρέας ("flesh")],<ref>{{cite web |last=Harper |first=Douglas |title=Pancreas |work=Online Etymology Dictionary |url=http://www.etymonline.com/index.php?term=pancreas |access-date=2007-04-04}}</ref> originally means [[sweetbread]],<ref name="Green2008">{{cite book| first = Tamara M. | last = Green | name-list-style = vanc |title=The Greek and Latin Roots of English|url=https://books.google.com/books?id=6gknyzq0uD8C&pg=PA176|year=2008|publisher=Rowman & Littlefield|isbn=978-0-7425-4780-3|page=176}}</ref> although literally meaning all-flesh, presumably because of its fleshy consistency. It was only in 1889 when [[Oskar Minkowski]] discovered that removing the pancreas from a dog caused it to become diabetic.<ref name="Karamanou2016">{{cite journal |last1=Karamanou |first1=M. |last2=Protogerou |first2=A. |last3=Tsoucalas |first3=G. |last4=Androutsos |first4=G. |last5=Poulakou-Rebelakou |first5=E. |title=Milestones in the history of diabetes mellitus: The main contributors. |journal=World Journal of Diabetes |date=10 January 2016 |volume=7 |issue=1 |pages=1–7 |doi=10.4239/wjd.v7.i1.1 |pmid=26788261|pmc=4707300 |doi-access=free }}</ref> Insulin was later isolated from pancreatic islets by [[Frederick Banting]] and [[Charles Best (medical scientist)|Charles Best]] in 1921.<ref name=Karamanou2016 />

The way the tissue of the pancreas has been viewed has also changed. Previously, it was viewed using simple [[staining]] methods such as [[H&E stain]]s. Now, [[immunohistochemistry]] can be used to more easily differentiate cell types. This involves visible antibodies to the products of certain cell types, and helps identify with greater ease cell types such as alpha and beta cells.{{sfn|Wheater's Histology|2013|pp=332-333}}

==Other animals==
Pancreatic tissue is present in all [[vertebrate]]s, but its precise form and arrangement varies widely. There may be up to three separate pancreases, two of which arise from the [[pancreatic bud]], and the other [[dorsally]]. In most species (including humans), these "fuse" in the adult, but there are several exceptions. Even when a single pancreas is present, two or three pancreatic ducts may persist, each draining separately into the duodenum (or equivalent part of the foregut). [[Bird]]s, for example, typically have three such ducts.<ref name=VB>{{cite book | last1 = Romer | first1 = Alfred Sherwood| last2 = Parsons | first2 = Thomas S. | name-list-style = vanc |year=1977 |title=The Vertebrate Body |publisher=Holt-Saunders International |location= Philadelphia, PA|pages= 357–59 |isbn=978-0-03-910284-5 }}</ref>

In [[teleost]] fish, and a few other species (such as [[rabbit]]s), there is no discrete pancreas at all, with pancreatic tissue being distributed diffusely across the [[mesentery]] and even within other nearby organs, such as the [[liver]] or [[spleen]]. In a few teleost species, the endocrine tissue has fused to form a distinct gland within the abdominal cavity, but otherwise it is distributed among the exocrine components. The most primitive arrangement, however, appears to be that of [[lamprey]]s and [[lungfish]], in which pancreatic tissue is found as a number of discrete nodules within the wall of the gut itself, with the exocrine portions being little different from other glandular structures of the intestine.<ref name=VB/>

==Cuisine==

The pancreas of [[veal|calf]] (''ris de veau'') or [[Lamb and mutton|lamb]] (''ris d'agneau''), and, less commonly, of [[beef]] or [[pork]], are used as food under the [[culinary name]] of [[sweetbread]].<ref>''[[Oxford Companion to Food]]''; ''[[Oxford English Dictionary]]''</ref><ref name="Leiths">{{cite book |last1=Spaull |first1=Susan |last2=Bruce-Gardyne |first2=Lucinda | name-list-style = vanc |title=Leiths Techniques Bible |date=2003 |publisher=Bloomsbury |isbn=0-7475-6046-3 |page=451 |edition= 1 }}</ref>

== Additional images ==
<gallery>
File:Axial section of the epigastric region showing pancreas, splenic vein, IVC, aorta.jpg|A normal pancreas on ultrasound.
File:Pancreas ultrasound normal.jpg|Identifying pancreas on [[abdominal ultrasonography]] when it is partly obscured by bowel gas.
File:Gray1102.png|Pancreas of a human embryo at end of sixth week
File:Sobo 1906 393.png|The pancreas and its surrounding structures
File:Slide2duo.jpg|Duodenum and pancreas. Deep dissection.
</gallery>

== References ==
{{Anatomy-terms}}
{{Reflist}}

===Bibliography===

* {{Cite book|title=Ganong's review of medical physiology|author1=Barrett, Kim E.|others=Barman, Susan M.,, Brooks, Heddwen L., Yuan, Jason X.-J.|isbn=978-1-260-12240-4|edition=26th|location=New York|oclc=1076268769|year=2019|ref={{harvid|Ganong's Physiology|2019}}}}
* {{Cite book |editor=Beger HG|title=The pancreas: an integrated textbook of basic science, medicine, and surgery|date=2018|isbn=978-1-119-18841-4|location=Hoboken, NJ|oclc=1065547789|edition=third|ref={{harvid|Beger's|2018}}}}
* {{cite book |last1=Kasper |first1=Dennis |last2=Fauci |first2=Anthony |last3=Hauser |first3=Stephen |last4=Longo |first4=Dan |last5=Jameson |first5=J. |last6=Loscalzo |first6=Joseph | name-list-style = vanc |title=Harrison's Principles of Internal Medicine |date=2015 |publisher=McGraw-Hill Professional |isbn=978-0-07-180215-4 |edition= 19|ref={{harvid|Harrison's|2015}}}}
* {{cite book |editor-last1=Ralston |editor-first1=Stuart H. |editor-last2=Penman |editor-first2=Ian D. |editor-last3=Strachan |editor-first3=Mark W. |editor-last4=Hobson |editor-first4=Richard P. | name-list-style = vanc |title=Davidson's principles and practice of medicine |date=2018 |publisher=Elsevier |isbn=978-0-7020-7028-0 |edition= 23rd|ref={{harvid|Davidson's|2018}}}}
* {{cite book |editor=Standring, Susan|editor2=Borley, Neil R.|title=Gray's anatomy: the anatomical basis of clinical practice|date=2008|publisher=Churchill Livingstone|location=London|isbn=978-0-8089-2371-8|edition= 40th|ref={{harvid|Gray's|2008}}|display-editors=etal}}
* {{Cite book |editor=Standring, Susan|title=Gray's anatomy: the anatomical basis of clinical practice|isbn=978-0-7020-5230-9|edition=41st|location=Philadelphia|oclc=920806541|year=2016|ref={{harvid|Gray's|2016}}}}
* {{cite book |last1=Young |first1=Barbara |last2=O'Dowd |first2=Geraldine |last3=Woodford |first3=Phillip |title=Wheater's functional histology: a text and colour atlas.|publisher=Elsevier |location=Philadelphia |date=2013|isbn=978-0-7020-4747-3 |edition=6th|ref={{harvid|Wheater's Histology|2013}}}}

== External links ==
{{Commons category}}
* [https://www.proteinatlas.org/humanproteome/pancreas Pancreas at the Human Protein Atlas]
* [https://www.youtube.com/watch?v=GWV9vHVmeL0&t=94s Pancreatic Diseases – English – The Gastro Specialist]

{{Accessory digestive glands}}
{{Portal bar|Anatomy}}
{{Authority control}}

[[Category:Pancreas| ]]