The exocrine pancreas has ducts which are arranged in clusters called acini (singular acinus). Pancreatic secretions are secreted into the lumen of the acinus, and then accumulate in intralobular ducts that drain to the main pancreatic duct, which drains directly into the duodenum. Exocrine gland refers to glands that secrete their products via a duct. ... For the song by Weird Al Yankovic, see Pancreas (song) The pancreas is an organ in the digestive and endocrine system that serves two major functions: exocrine (producing pancreatic juice containing digestive enzymes) and endocrine (producing several important hormones, including insulin). ... A acinus (adjective: acinar, plural acini) refers to the berry-shaped termination of an exocrine gland, where the secretion is produced. ... Lumen can mean: Lumen (unit), the SI unit of luminous flux Lumen (anatomy), the cavity or channel within a tubular structure Thylakoid lumen, the inner membrane space of the chloroplast 141 Lumen, an asteroid discovered by the French astronomer Paul Henry in 1875 Lumen (band), an American post-rock band... An intralobular duct is the portion of an exocrine gland inside a lobule, leading directly from intercalated duct to an interlobular duct. ... A duct joining the pancreas to the bile duct to supply pancreatic juice which aid in digestion provided by the exocrine pancreas. ... In anatomy of the digestive system, the duodenum is a hollow jointed tube connecting the stomach to the jejunum. ...

Control of the exocrine function of the pancreas are via the hormones gastrin, cholecystokinin and secretin, which are hormones secreted by cells in the stomach and duodenum, in response to distension and/or food and which cause secretion of pancreatic juices. In humans, gastrin is a hormone that stimulates secretion of gastric acid by the stomach. ... Cholecystokinin (from Greek chole, bile; cysto, sac; kinin, move; hence, move the bile-sac (gall bladder)) is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. ... Secretin is a peptide hormone produced in the S cells of the duodenum. ... A hormone (from Greek horman - to set in motion) is a chemical messenger from one cell (or group of cells) to another. ... In anatomy, the stomach (in ancient Greek στόμαχος) is an organ of the gastrointestinal tract involved in the second phase of digestion, following mastication. ... In anatomy of the digestive system, the duodenum is a hollow jointed tube connecting the stomach to the jejunum. ...

There are two main classes of exocrine pancreatic secretions:

Pancreatic secretions from ductal cells contain bicarbonate ions and are alkaline in order to neutralize the acidic chyme that the stomach churns out. In inorganic chemistry, a bicarbonate (IUPAC-recommended nomenclature: hydrogencarbonate) is an intermediate form in the deprotonation of carbonic acid. ... In some animals spindle-shaped cells occupy the center of the alveolus of the pancreas and are known as the centroacinar cells of Langerhans. ... Secretin is a peptide hormone produced in the S cells of the duodenum. ... Neuraminidase ribbon diagram An enzyme (in Greek en = in and zyme = blend) is a protein, or protein complex, that catalyzes a chemical reaction and also controls the 3D orientation of the catalyzed substrates. ... Cholecystokinin (from Greek chole, bile; cysto, sac; kinin, move; hence, move the bile-sac (gall bladder)) is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. ... In inorganic chemistry, a bicarbonate (IUPAC-recommended nomenclature: hydrogencarbonate) is an intermediate form in the deprotonation of carbonic acid. ... The common (Arrhenius) definition of a base is a chemical compound that either donates hydroxide ions or absorbs hydrogen ions when dissolved in water. ... Chyme is the liquid substance found in the stomach before passing the Pyloric valve and entering the duodenum. ...

The pancreas is also the main source of enzymes for digesting fats (lipids) and proteins. (The enzymes that digest polysaccharides, by contrast, are primarly produced by the walls of the intestines.) Fats is the plural for fat, a generic term for a class of lipids in biochemistry. ... Figure 1: Basic lipid structure. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... Polysaccharides (sometimes called glycans) are relatively complex carbohydrates. ... In anatomy, the intestine is the portion of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine (or colon). ...

The cells are filled with secretory granules containing the precursor digestive enzymes. The major proteases which the pancreas secretes are trypsinogen and chymotrypsinogen. Secreted to a lesser degree are pancreatic lipase and pancreatic amylase). Peptidases (proteases [pronounced pro-tea-aces] and proteolytic enzymes are also commonly used) are enzymes which break peptide bonds of proteins. ... Trypsinogen (EC 3. ... Chymotrypsinogen is a precursor of the digestive enzyme chymotrypsin (zymogen). ... Pancreatic lipase is an enzyme (more specifically, a lipase) secreted from the pancreas that uses hydrolysis to break apart fat molecules. ... α-Amylase Amylase (EC 3. ...

It is important to synthesize inactive enzymes in the pancreas to avoid autodegradation, which can lead to pancreatitis. These granules are termed zymogen granules (the term "zymogen" referring to the inactive precursor enzymes). Trypsinogen is an inactivated forms of trypsin, and chymotrypsinogen is an inactivated form of chymotrypsin. Pancreatitis is inflammation of the pancreas. ... A zymogen or a proenzyme, is an inactive enzyme precursor. ... Trypsin (EC 3. ... Chymotrypsin Chymotrypsin (bovine γ chymotrypsin: PDB 1AB9, EC 3. ...

Once released in the intestine, the enzyme enterokinase present in the intestinal mucosa activates trypsinogen by cleaving it to form trypsin. The free trypsin then cleaves the rest of the trypsinogen and chymotrypsinogen to their active forms. Enterokinase is used to activate the zymogen, trypsinogen, to trypsin. ... The mucous membranes (or mucosa) are linings of ectodermic origin, covered in epithelium, that line various body cavities and internal organs. ...

External links

• MeSH Exocrine+pancreas
• Dorlands/Elsevier p_02/12608706
• Histology at BU 10404loa
• Histology at anhb.uwa.edu.au
• Histology at pathguy.com
• Histology at ucsf.edu
• Diagram at gastroresource.com