The Cholecystokinin A receptor is a human

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, respo ...

, also known as CCKAR or CCK₁, with CCK₁ now being the

IUPHAR The International Union of Basic and Clinical Pharmacology (IUPHAR) is a voluntary, non-profit association representing the interests of scientists in pharmacology-related fields to facilitate ''Better Medicines through Global Education and Resear ...

-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 Domain may refer to: Mathematics *Domain of a function, the set of input values for which the (total) function is defined **Domain of definition of a partial function **Natural domain of a partial function **Domain of holomorphy of a function * Do ...

of this protein adopts a

tertiary structure Protein tertiary structure is the three dimensional shape of a protein. The tertiary structure will have a single polypeptide chain "backbone" with one or more protein secondary structures, the protein domains. Amino acid side chains may i ...

consisting of a few

helical Helical may refer to: * Helix, the mathematical concept for the shape * Helical engine, a proposed spacecraft propulsion drive * Helical spring, a coilspring * Helical plc, a British property company, once a maker of steel bar stock * Helicoil A t ...

turns and a

disulfide In biochemistry, a disulfide (or disulphide in British English) refers to a functional group with the structure . The linkage is also called an SS-bond or sometimes a disulfide bridge and is usually derived by the coupling of two thiol groups. In ...

-cross linked loop. It is required for interaction of the cholecystokinin A receptor with its corresponding

hormonal 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 f ...

ligand In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's elec ...

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 peptide hormone of the gastrointestinal system responsible for stimulating the digestion of fat and ...

CCK-4 Cholecystokinin tetrapeptide (CCK-4, Trp- Met- Asp- Phe-NH2) is a peptide fragment derived from the larger peptide hormone cholecystokinin. Unlike cholecystokin which has a variety of roles in the gastrointestinal system as well as central nervou ...

* SR-146,131 * A-71623 - modified tetrapeptide, potent and selective CCK_A agonist, IC₅₀ 3.7nM, 1200x selectivity over CCK_B, CAS# 130408-77-4

Antagonists

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, ...

* Lorglumide *

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 ga ...

Dexloxiglumide Dexloxiglumide is a drug which acts as a cholecystokinin antagonist, selective for the CCKA subtype. It inhibits gastrointestinal motility and reduces gastric secretions, and despite older selective CCKA antagonists such as lorglumide and deva ...

Asperlicin Asperlicin is a mycotoxin, derived from the fungus '' Aspergillus alliaceus''. It acts as a selective antagonist for the cholecystokinin receptor CCKA, and has been used as a lead compound A lead compound (, i.e. a "leading" compound, not to be ...

* SR-27897 * IQM-95333 * JNJ-17156516

Function

Selective Ligands

Agonists

Antagonists

See also

References

External links

Further reading