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Cholecystokinin Antagonist
A cholecystokinin receptor antagonist is a specific type of receptor antagonist which blocks the receptor sites for the peptide hormone cholecystokinin ( CCK). There are two subtypes of this receptor known at present, defined as CCKA and CCKB (also called CCK-1 and CCK-2). The CCKA receptor is mainly expressed in the small intestine, and is involved in the regulation of enzyme secretion by the pancreas, secretion of gastric acid in the stomach, intestinal motility and signaling of satiety (fullness). The CCKB receptor is expressed mainly in the central nervous system, and has functions relating to anxiety and the perception of pain. Antagonists for the CCK receptors can thus have multiple functions in both the gut and brain. The best known CCK receptor antagonist is the non-selective antagonist proglumide, which blocks both CCKA and CCKB receptors, and was originally developed for the treatment of stomach ulcers. This action derived from its blockade of CCKA receptor in the gut an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Receptor Antagonist
A receptor antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist. Antagonist drugs interfere in the natural operation of receptor proteins.Pharmacology Guide: In vitro pharmacology: concentration-response curves " '' GlaxoWellcome.'' Retrieved on December 6, 2007. They are sometimes called blockers; examples include alpha blockers, |
Peptide
Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A polypeptide is a longer, continuous, unbranched peptide chain. Hence, peptides fall under the broad chemical classes of biological polymers and oligomers, alongside nucleic acids, oligosaccharides, polysaccharides, and others. A polypeptide that contains more than approximately 50 amino acids is known as a protein. Proteins consist of one or more polypeptides arranged in a biologically functional way, often bound to ligands such as coenzymes and cofactors, or to another protein or other macromolecule such as DNA or RNA, or to complex macromolecular assemblies. Amino acids that have been incorporated into peptides are termed residues. A water molecule is released during formation of each amide bond.. All peptides except cyclic pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hormone
A hormone (from the Greek participle , "setting in motion") is a class of signaling molecules in multicellular organisms that are sent to distant organs by complex biological processes to regulate physiology and behavior. Hormones are required for the correct development of animals, plants and fungi. Due to the broad definition of a hormone (as a signaling molecule that exerts its effects far from its site of production), numerous kinds of molecules can be classified as hormones. Among the substances that can be considered hormones, are eicosanoids (e.g. prostaglandins and thromboxanes), steroids (e.g. oestrogen and brassinosteroid), amino acid derivatives (e.g. epinephrine and auxin), protein or peptides (e.g. insulin and CLE peptides), and gases (e.g. ethylene and nitric oxide). Hormones are used to communicate between organs and tissues. In vertebrates, hormones are responsible for regulating a variety of physiological processes and behavioral activities such as diges ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholecystokinin
Cholecystokinin (CCK or CCK-PZ; from Greek ''chole'', "bile"; ''cysto'', "sac"; ''kinin'', "move"; hence, ''move the bile-sac (gallbladder)'') is a peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and protein. Cholecystokinin, formerly called pancreozymin, is synthesized and secreted by enteroendocrine cells in the duodenum, the first segment of the small intestine. Its presence causes the release of digestive enzymes and bile from the pancreas and gallbladder, respectively, and also acts as a hunger suppressant. History Evidence that the small intestine controls the release of bile was uncovered as early as 1856, when French physiologist Claude Bernard showed that when dilute acetic acid was applied to the orifice of the bile duct, the duct released bile into the duodenum. In 1903 the French physiologist showed that this reflex was not mediated by the nervous system. In 1904 the French physiologist Charles Fleig showed that the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholecystokinin Receptor
Cholecystokinin receptors or CCK receptors are a group of G-protein coupled receptors which bind the peptide hormones cholecystokinin (CCK) and gastrin. There are two different subtypes CCKA and CCKB which are ~50% homologous: Various cholecystokinin antagonists have been developed and are used in research, although the only drug of this class that has been widely marketed to date is the anti-ulcer drug proglumide Proglumide (Milid) is a drug that inhibits gastrointestinal motility and reduces gastric secretions. It acts as a cholecystokinin antagonist, which blocks both the CCKA and CCKB subtypes. It was used mainly in the treatment of stomach ulcers, .... References External links * G protein-coupled receptors {{Cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholecystokinin A Receptor
The Cholecystokinin A receptor is a human protein, also known as CCKAR or CCK1, with CCK1 now being the IUPHAR-recommended name. Function This gene encodes a G-protein coupled receptor that binds sulfated members of the cholecystokinin (CCK) family of peptide hormones. This receptor is a major physiologic mediator of pancreatic enzyme secretion and smooth muscle contraction of the gallbladder and stomach. In the central and peripheral nervous system this receptor regulates satiety and the release of beta-endorphin and dopamine. The extracellular, N-terminal, domain of this protein adopts a tertiary structure consisting of a few helical turns and a disulfide-cross linked loop. It is required for interaction of the cholecystokinin A receptor with its corresponding hormonal ligand. Selective Ligands Agonists * Cholecystokinin Cholecystokinin (CCK or CCK-PZ; from Greek ''chole'', "bile"; ''cysto'', "sac"; ''kinin'', "move"; hence, ''move the bile-sac (gallbladder)'') is a pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cholecystokinin B Receptor
The cholecystokinin B receptor also known as CCKBR or CCK2 is a protein that in humans is encoded by the ''CCKBR'' gene. This gene encodes a G protein-coupled receptor for gastrin and cholecystokinin (CCK), regulatory peptides of the brain and gastrointestinal tract. This protein is a type B gastrin receptor, which has a high affinity for both sulfated and nonsulfated CCK analogs and is found principally in the central nervous system and the gastrointestinal tract. A misspliced transcript variant including an intron has been observed in cells from colorectal and pancreatic tumors. CNS effects CCK receptors significantly influence neurotransmission in the brain, regulating anxiety, feeding, and locomotion. CCK-B expression may correlate parallel to anxiety and depression phenotypes in humans. CCK-B receptors possess a complex regulation of dopamine activity in the brain. CCK-B activation appears to possess a general inhibitory action on dopamine activity in the brain, opposing t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proglumide
Proglumide (Milid) is a drug that inhibits gastrointestinal motility and reduces gastric secretions. It acts as a cholecystokinin antagonist, which blocks both the CCKA and CCKB subtypes. It was used mainly in the treatment of stomach ulcers, although it has now been largely replaced by newer drugs for this application. An interesting side effect of proglumide is that it enhances the analgesia produced by opioid drugs, and can prevent or even reverse the development of tolerance to opioid drugs. This can make it a useful adjuvant treatment to use alongside opioid drugs in the treatment of chronic pain conditions such as cancer, where opioid analgesics may be required for long periods and development of tolerance reduces clinical efficacy of these drugs. Proglumide has also been shown to act as a δ-opioid agonist, which may contribute to its analgesic effects. Proglumide also works as a placebo effect amplifier for pain conditions. When injected visibly to a subject, its a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lorglumide
Lorglumide (CR-1409) is a drug which inhibits gastrointestinal motility and reduces gastric secretions, acting as a cholecystokinin antagonist, with fairly high selectivity for the CCKA subtype. It has been suggested as a potential treatment for a variety of gastrointestinal problems including stomach ulcers, irritable bowel syndrome, dyspepsia, constipation and pancreatitis, as well as some forms of cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ..., but animal and human testing has produced inconsistent results and no clear therapeutic role has been established, although it is widely used in scientific research. References {{Drugs for peptic ulcer and GORD Cholecystokinin antagonists Chloroarenes Benzamides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devazepide
Devazepide (L-364,718, MK-329) is benzodiazepine drug, but with quite different actions from most benzodiazepines, lacking affinity for GABAA receptors and instead acting as an CCKA receptor antagonist. It increases appetite and accelerates gastric emptying, and has been suggested as a potential treatment for a variety of gastrointestinal problems including dyspepsia, gastroparesis and gastric reflux. It is also widely used in scientific research into the CCKA receptor. Synthesis Devazepide is synthesised in a similar manner to other benzodiazepines. See also *Benzodiazepine *Cholecystokinin antagonist A cholecystokinin receptor antagonist is a specific type of receptor antagonist which blocks the receptor sites for the peptide hormone cholecystokinin ( CCK). There are two subtypes of this receptor known at present, defined as CCKA and CCKB (al ... References {{Benzodiazepines Benzodiazepines Cholecystokinin antagonists Indoles ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CI-988
CI-988 (PD-134,308) is a drug which acts as a cholecystokinin antagonist, selective for the CCKB subtype. In animal studies it showed anxiolytic effects and potentiated the analgesic action of both morphine Morphine is a strong opiate that is found naturally in opium, a dark brown resin in poppies (''Papaver somniferum''). It is mainly used as a analgesic, pain medication, and is also commonly used recreational drug, recreationally, or to make ... and endogenous opioid peptides, as well as preventing the development of tolerance to opioids and reducing symptoms of withdrawal. Consequently, it was hoped that it might have clinical applications for the treatment of pain and anxiety in humans, but trial results were disappointing with only minimal therapeutic effects observed even at high doses. The reason for the failure of CI-988 and other CCKB antagonists in humans despite their apparent promise in pre-clinical animal studies is unclear, although poor pharmacokinetic prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
British Journal Of Pharmacology
The ''British Journal of Pharmacology'' is a biweekly peer-reviewed medical journal covering all aspects of experimental pharmacology. It is published for the British Pharmacological Society by Wiley-Blackwell. It was established in 1946 as the ''British Journal of Pharmacology and Chemotherapy''. The journal obtained its current title in 1968. The current editor-in-chief is Amrita Ahluwalia. Previous editors-in-chief include Ian McGrath, Humphrey Rang, Alan North, Phil Moore, Bill Large, and Tony Birmingham. A sister journal, also published for the British Pharmacological Society by Wiley-Blackwell is the '' British Journal of Clinical Pharmacology''. The journal publishes research papers, review articles, commentaries and correspondence in all fields of pharmacology. It also publishes themed issues, as well as supplements. ''The Concise Guide to PHARMACOLOGY'' The ''Concise Guide to PHARMACOLOGY'' is a supplement of the ''British Journal of Pharmacology'', replacing the "Guide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
