Pancreatic Cholecystokinin

HERZIG K H, BARDOCZ s, GRANT G, NUSTEDE R, FOLSCH u R, PUSZTAi A (1997) Red kidney bean lectin is a potent cholecystokinin releasing stimulus in the rat inducing pancreatic growth. Gut. 41 333-8. 

JAKOB S, MOSENTHIN R, THAELA M J, WESTROM B R, REHFELD J F, OLSEN O, KARLSSON S, AHREN B, OHLSSON A, KARLSSON B w, PIERZYNOWSKI s G (2000) The influence of potato fibre on exocrine pancreatic secretions and on plasma levels of insulin, secretin and cholecystokinin in growing pigs. Arch Tierernahr. 53 273-91. 

Most pancreatic secretion takes place during the intestinal phase. The intestinal hormone secretin stimulates release of a large volume of pancreatic juice with a high concentration of bicarbonate ion. Secretin is released in response to acidic chyme in the duodenum (maximal release at pH < 3.0). The intestinal hormone cholecystokinin is released in response to the presence of the products of protein and lipid digestion. Cholecystokinin then stimulates the release of digestive enzymes from the pancreas. 

Bile is secreted by the liver, stored in the gallbladder, and used in the small intestine. It is transported toward the small intestine by the hepatic duct (from the liver) and the cystic duct (from the gallbladder), which join to form the common bile duct. Pancreatic juice is transported toward the small intestine by the pancreatic duct. The common bile duct and the pancreatic duct join to form the hepatopancreatic ampulla, which empties into the duodenum. The entrance to the duodenum is surrounded by the Sphincter of Oddi. This sphincter is closed between meals in order to prevent bile and pancreatic juice from entering the small intestine it relaxes in response to the intestinal hormone cholecystokinin, thus allowing biliary and pancreatic secretions to flow into the duodenum. 

Cholecystokinin CCKa (CCKj) Human cDNA Anorexia, gastrointestinal disorders, pancreatitis, satiety, diabetes, obesity, nociception, schizophrenia, Parkinson s disease, addiction, cancer Pancreatic enzyme secretion, potentiation of opiate analgesia, gallbladder contraction, gut motility, growth promoting effects on some tumors, dopamine release... 

Specific hormones Insulin, glucagon, somatostatin, gastrin, pancreatic polypeptide, serotonin, vasoactive intestinal peptide, cholecystokinin... 

Malhotra R, Singh L, Eng J, Raufman J-P. (1992) Exendin-4, a new peptide from Heloderma suspectum venom, potentiates cholecystokinin-induced amylase release from rat pancreatic acini. Regul Pept 41 149-156. 

Pancreatic enemies (B) from slaughtered animals are used to relieve excretory insufficiency of the pancreas ( disrupted digestion of fats steatorrhea, inter alia). Normally, secretion of pancreatic enzymes is activated by cholecystokinin ancreozymin, the en-terohormone that is released into blood from the duodenal mucosa upon contact with chyme. With oral administration of pancreatic enzymes, allowance must be made for their partial inactivation by gastric acid (the lipases, particularly). Therefore, they are administered in acid-resistant dosage forms. 

Pandya PK, Huang SC, Talkad VD, et al Biochemical regulation of the three different states of the cholecystokinin (CCK) receptor in pancreatic acini. Biochim Biophys Acta 1224 117-126, 1994... 

It inhibits the secretion of numerous hormones and transmitters, including gastrin, cholecystokinin, glucagon, growth hormone, insulin, secretin, pancreatic polypeptide, vasoactive intestinal peptide, and 5-HT. 

Sundaram S, Dayan AD. Effects of a cholecystokinin receptor antagonist on rat exocrine pancreatic response to raw soya flour. Human Exp Toxicol 1991 10 179. 

Release of zymogens The release and activation of the pancreatic zymogens is mediated by the secretion of cholecystokinin and secretin, two polypeptide hormones of the digestive tract (see p. 174). 

In the duodenum, dietary lipids are degraded by pancreatic enzymes triacylglycerol by pancreatic lipase, phospholipids by phospholipase A2 and lysophospholipase, and cholesteryl esters by cholesterol esterase. Enzyme release from the pancreas is controlled by cholecystokinin, produced by cells in the intestinal mucosa. 

When cholecystokinin interacts with its receptors on pancreatic cell surface, the... 

Cholecystokinin (CCK) PhLC stimulation Gpic pancreatic acini... 

In principle, pancreatic function can be tested by quantifying exocrine secretory output directly by duodenal intubation, juice aspiration, and measurement of enzymes under defined stimulatory conditions, usually by intravenous application of cholecystokinin and/or secretin. ERCP-guided direct cannulation and collection of pure pancreatic juice is, however, not a routine procedure due to its substantial inherent risk of iatrogenic pancreatitis. Pancreatic enzymes can also be quantified indirectly by measuring a representative enzyme in a stool sample. 

The secretion after injection of the test compound is compared with the pre-test values. Secretin or cholecystokinin (CCK) increases pancreatic secretion volume in a dose-dependent manner and can be used as a positive standard. 

Ito et al. (1994) studied the inhibition of CCK-8-induced pancreatic amylase secretion by a cholecystokinin type-A receptor antagonist in rats. 

Tachibana I Kanagawa K, Yamamoto Y, Otsuki M (1996) Pharmacological profile of a new serine derivative cholecystokinin receptor antagonist TP-680 on pancreatic, biliary and gastric function. J Pharmacol Exp Ther 279 1404-1412... 

Ninomiya et al. (1998) studied the effects of a cholecystokinin A receptor antagonist on pancreatic exocrine secretion stimulated by exogenously administered CCK-8 in conscious dogs with chronic pancreatic fistula. 

Niebergall-Roth E, Teyssen S, Singer MV (1997) Pancreatic exocrine studies in intact animals history and current methods. Lab Animal Science 47 606-615 Ninomiya K, Saito T, Wakatsuki K et al. (1998) Effects of loxiglumide on pancreatic exocrine secretion stimulated by cholecystokinin-8 in conscious dogs. Arzneim Forsch/Drug Res 48 52-54... 

Cholecystokinin receptors are the GPCRs CCK-A and CCK-B. The C-terminal sulfated octapeptide CCK fragment (CCK8) is a major neuropeptide. CCK is involved in anorexia, cardiovascular tonus, central respiratory control, nociception, pancreatic exocrine secretion, gastric emptying, memory, vigilance and emotional states such as anxiety and panic. 

Cholecystokinin (= Pancreozymin)] (4kDa protein) Animals brain GI tract CCK-R agonist ianorexigenic, nociception, T pancreatic exocrine secretion, J- gastric emptying]... 

Q10 Normally, pancreatic secretion is stimulated by eating. The factors involved are both nervous and hormonal. Pancreatic secretion is increased by vagal (parasympathetic) stimulation and inhibited by sympathetic stimulation. Cholecystokinin (CCK), released from the wall of the duodenum, stimulates pancreatic juice, which is rich in enzymes. Secretin (the first hormone to be discovered, by Bayliss and Starling), which is also produced in the duodenum, stimulates a pancreatic fluid with a high bicarbonate content. 

---