Stomach 39747 225036537 2008-07-11T16:06:07Z Felizdenovo 4750961 {{Nofootnotes|date=June 2008}}{{Refimprove|date=June 2008}}{{Infobox Anatomy |Name = Stomach |Latin = Ventriculus |Greek = Gaster |GraySubject = 247 |GrayPage = 1161 |Image = Stomach_diagram.svg |Caption = The location of the stomach in the body. |Image2 = Illu stomach.jpg |Caption2='''Diagram from [http://training.seer.cancer.gov/ss_module07_ugi/unit02_sec02_anatomy.html cancer.gov]:<BR>'''* 1. [[Body of stomach]]<BR>* 2. [[Fundus (stomach)|Fundus]]<BR>* 3. [[Anterior wall]]<BR>* 4. [[Greater curvature]]<BR>* 5. [[Lesser curvature]]<BR>* 6. [[Cardia]]<BR>* 9. [[Pyloric sphincter]]<BR>* 10. [[Pyloric antrum]]<BR>* 11. [[Pyloric canal]]<BR>* 12. [[Angular notch]]<BR>* 13. [[Gastric canal]]<BR>* 14. [[Rugal folds]]<BR><BR>[[Work of the United States Government]] |Precursor = |System = |pqp35ykyj 4oh |Artery = |Vein = |Nerve = [[celiac ganglia]], [[vagus]]<ref>{{GeorgiaPhysiology|6/6ch2/s6ch2_30}}</ref> |Lymph = celiac [[preaortic lymph node]]s<ref>{{NormanAnatomy|stomach}}</ref> |MeshName = Stomach |MeshNumber = A03.556.875.875 |DorlandsPre = g_03 |DorlandsSuf = 12386049 | }} In [[anatomy]], the '''stomach''' is a J-shaped hollow muscular [[organ (anatomy)|organ]] of the [[gastrointestinal tract]] involved in the second phase of [[digestion]], following [[mastication]]. The word ''stomach'' is derived from the [[Latin]] ''stomachus'', which derives from the [[Greek language|Greek]] word ''stomachos'' ({{polytonic|στόμαχος}}). The words ''gastro-'' and ''gastric'' (meaning related to the stomach) are both derived from the Greek word ''gaster'' ({{polytonic|γαστήρ}}). ==Functions== Absorption of [[vitamin B12]] from the small intestine is dependent on [[conjugation]] to a [[glycoprotein]] called [[intrinsic factor]] which is produced by [[parietal cells]] of the stomach. Other functions include absorbing some ions, water, and some [[lipid]] soluble compounds such as [[alcohol]], [[aspirin]], and [[caffeine]]. ==Histology of the human stomach== ===Layers=== Like the other parts of the gastrointestinal tract, the stomach walls are made of the following layers, from inside to outside: {| class="wikitable" | [[mucosa]] || The first main layer. This consists of an [[epithelium]], the [[lamina propria]] underneath, and a thin layer of [[smooth muscle]] called the [[muscularis mucosae]]. |- | [[submucosa]] || This layer lies under the mucosa and consists of [[fibrous connective tissue]], separating the mucosa from the next layer. The [[Meissner's plexus]] is in this layer. |- | [[muscularis externa]] || Under the submucosa, the muscularis externa in the stomach differs from that of<!--parallelism, PLEASE--> other GI organs in that it has three layers of [[smooth muscle]] instead of two. * ''inner oblique layer:'' This layer is responsible for creating the motion that churns and physically breaks down the food. It is the only layer of the three which is not seen in other parts of the [[digestive system]]. The antrum has thicker skin cells in its walls and performs more forceful contractions than the fundus. * ''middle circular layer:'' At this layer, the [[pyloric valve|pylorus]] is surrounded by a thick circular muscular wall which is normally tonically constricted forming a functional (if not anatomically discrete) pyloric [[sphincter]], which controls the movement of [[chyme]] into the [[duodenum]]. This layer is concentric to the longitudinal axis of the stomach. * ''outer longitudinal layer:'' [[Auerbach's plexus]] is found between this layer and the middle circular layer. |- | [[serosa]] || This layer is under the muscularis externa, consisting of layers of connective tissue continuous with the [[peritoneum]]. |} [[Image:Stomach.JPG|thumb|200px|Cross section of stomach wall.]] [[Image:Pyloric stomach LPO.JPG|thumb|200px|Microscopic cross section of the pyloric part of the stomach wall.]] ===Glands=== ==Control of secretion and motility== The movement and the flow of chemicals into the stomach are controlled by both the [[autonomic nervous system]] and by the various digestive system [[hormone]]s: {| class="wikitable" | [[Gastrin]] || The hormone ''gastrin'' causes an increase in the secretion of HCl, pepsinogen and [[intrinsic factor]] from [[parietal cell]]s in the stomach. It also causes increased motility in the stomach. Gastrin is released by [[G-cells]] in the stomach to distenstion of the antrum, and digestive products. It is inhibited by a [[pH]] normally less than 4 (high acid), as well as the hormone [[somatostatin]]. |- | [[Cholecystokinin]] || ''Cholecystokinin'' (CCK) has most effect on the [[gall bladder]], but it also decreases gastric emptying and increases release of pancreatic juice which is alkaline and neutralizes the chyme. |- | [[Secretin]] || In a different and rare manner, ''secretin'', produced in the small intestine, has most effects on the pancreas, but will also diminish acid secretion in the stomach. |- | [[Gastric inhibitory peptide]] || ''Gastric inhibitory peptide'' (GIP) decreases both gastric acid and motility. |- | [[Enteroglucagon]] || ''enteroglucagon'' decreases both gastric acid and motility. |} Other than gastrin, these hormones all act to turn off the stomach action. This is in response to food products in the liver and gall bladder, which have not yet been absorbed. The stomach needs only to push food into the small intestine when the intestine is not busy. While the intestine is full and still digesting food, the stomach acts as storage for food. ==Diseases == {{Expand-section|date=July 2008}} ==References== {{reflist}} ==External links== {{wiktionary}} * {{HSW|stomach-growling|Why does my stomach growl?}} * [http://www.med.uiuc.edu/m1/biochemistry/TA%20reviews/sam/AminoAcids.htm Digestion of proteins in the stomach] * [http://uk.geocities.com/bacterial_ed/bacteria_and_food.htm Site with details of how ruminants process food] *[http://www.comedycentral.com/motherload/index.jhtml?ml_video=83957 Interview with Dr. Jerome Groopman, Highlight at 2:30] {{Digestive tract}} [[Category:Abdomen]] [[Category:Digestive system]] [[af:Maag]] [[ar:معدة]] [[gn:Py'a]] [[ay:Puraka]] [[bs:Želudac]] [[bg:Стомах]] [[ca:Estómac]] [[cs:Žaludek]] [[da:Mave]] [[de:Magen]] [[dv:މައިދާ]] [[et:Magu]] [[el:Στομάχι]] [[es:Estómago]] [[eo:Stomako]] [[eu:Urdail]] [[fa:معده]] [[fr:Estomac]] [[ko:위 (기관)]] [[hr:Želudac]] [[io:Stomako]] [[ig:Afọ]] [[id:Lambung]] [[iu:ᐊᕿᐊᕈᖅ/aqiaruq]] [[is:Magi]] [[it:Stomaco]] [[he:קיבה]] [[jv:Lambung]] [[ku:Mîde]] [[la:Stomachus]] [[lt:Skrandis]] [[ln:Líkundú]] [[hu:Gyomor]] [[mk:Желудник]] [[mr:जठर]] [[ms:Perut]] [[nl:Maag]] [[ja:胃]] [[ka:კუჭი]] [[no:Magesekken]] [[pag:Eges]] [[pl:Żołądek]] [[pt:Estômago]] [[qu:Hiq'i]] [[ru:Желудок человека]] [[scn:Stòmmacu]] [[simple:Stomach]] [[sk:Žalúdok]] [[sl:Želodec]] [[su:Burih]] [[fi:Mahalaukku]] [[sv:Magsäck]] [[tl:Sikmura]] [[te:జీర్ణకోశం]] [[th:กระเพาะอาหาร]] [[vi:Dạ dày]] [[tr:Mide]] [[uk:Шлунок]] [[fiu-vro:Mago]] [[yi:מאגען]] [[diq:Pize]] [[zh:胃]]