Target type: molecularfunction
Combining with gastrin and transmitting the signal across the membrane by activating an associated G-protein to initiate a change in cell activity. [GOC:ai, GOC:signaling]
Gastrin receptor activity is a molecular function associated with the G protein-coupled receptor known as the cholecystokinin receptor type B (CCKBR), also referred to as the gastrin receptor. This receptor plays a crucial role in regulating digestive processes, particularly in the stomach and the small intestine. Upon binding of gastrin, a peptide hormone, to the gastrin receptor, a signaling cascade is initiated. This cascade involves the activation of heterotrimeric G proteins, specifically Gαq/11 proteins, which in turn activate phospholipase C (PLC). PLC hydrolyzes phosphatidylinositol 4,5-bisphosphate (PIP2) into diacylglycerol (DAG) and inositol trisphosphate (IP3). DAG activates protein kinase C (PKC), while IP3 triggers the release of calcium ions (Ca2+) from intracellular stores. The combined effects of PKC activation and Ca2+ mobilization lead to a multitude of downstream cellular responses, including:
- Stimulation of gastric acid secretion by parietal cells, a key process in digestion.
- Stimulation of gastrin release from G cells in the stomach, which acts in an autocrine and paracrine manner to amplify the gastrin signaling pathway.
- Stimulation of smooth muscle contraction in the stomach and gallbladder, facilitating food movement and bile release.
- Stimulation of pancreatic enzyme secretion, which aids in digestion.
- Modulation of neuronal signaling in the gastrointestinal tract, contributing to the regulation of appetite and satiety.
Gastrin receptor activity is tightly regulated to ensure proper digestion and prevent detrimental effects such as ulcers and gastrointestinal disorders. Dysregulation of gastrin signaling can lead to various pathological conditions, emphasizing the importance of understanding the molecular mechanisms involved in this receptor activity.'
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| Protein | Definition | Taxonomy |
|---|---|---|
| Gastrin/cholecystokinin type B receptor | A cholecystokinin receptor 2 that is encoded in the genome of cow. [OMA:P79266, PRO:DNx] | Bos taurus (cattle) |
| Gastrin/cholecystokinin type B receptor | A cholecystokinin receptor 2 that is encoded in the genome of dog. [OMA:P30552, PRO:DNx] | Canis lupus familiaris (dog) |
| Gastrin/cholecystokinin type B receptor | A cholecystokinin receptor 2 that is encoded in the genome of human. [PRO:WCB, UniProtKB:P32239] | Homo sapiens (human) |
| Compound | Definition | Classes | Roles |
|---|---|---|---|
| 5-methoxytryptamine | 5-methoxytryptamine : A member of the class of tryptamines that is the methyl ether derivative of serotonin. 5-Methoxytryptamine: Serotonin derivative proposed as potentiator for hypnotics and sedatives. | aromatic ether; primary amino compound; tryptamines | 5-hydroxytryptamine 2A receptor agonist; 5-hydroxytryptamine 2B receptor agonist; 5-hydroxytryptamine 2C receptor agonist; antioxidant; cardioprotective agent; human metabolite; mouse metabolite; neuroprotective agent; radiation protective agent; serotonergic agonist |
| fluoxetine | fluoxetine : A racemate comprising equimolar amounts of (R)- and (S)-fluoxetine. A selective serotonin reuptake inhibitor (SSRI), it is used (generally as the hydrochloride salt) for the treatment of depression (and the depressive phase of bipolar disorder), bullimia nervosa, and obsessive-compulsive disorder. Fluoxetine: The first highly specific serotonin uptake inhibitor. It is used as an antidepressant and often has a more acceptable side-effects profile than traditional antidepressants. N-methyl-3-phenyl-3-[4-(trifluoromethyl)phenoxy]propan-1-amine : An aromatic ether consisting of 4-trifluoromethylphenol in which the hydrogen of the phenolic hydroxy group is replaced by a 3-(methylamino)-1-phenylpropyl group. | (trifluoromethyl)benzenes; aromatic ether; secondary amino compound | |
| indopan | alpha-methyltryptamine : A tryptamine derivative having a methyl substituent at the alpha-position. indopan: RN given refers to parent cpd without isomeric designation | tryptamines | |
| 5-methoxy-alpha-methyltryptamine | 5-methoxy-alpha-methyltryptamine: RN given refers to parent cpd without isomeric designation | tryptamines | |
| spiroglumide | spiroglumide: a CCK receptor antagonist; antigastrin; structure given in first source | ||
| Pyrrolidine-1-carbonitrile | pyrrolidines | ||
| enkephalin, d-penicillamine (2,5)- | DPDPE : A heterodetic cyclic peptide that is a cyclic enkephalin analogue, having D-penicillaminyl residues located at positions 2 and 5, which form the heterocycle via a disulfide bond. Enkephalin, D-Penicillamine (2,5)-: A disulfide opioid pentapeptide that selectively binds to the DELTA OPIOID RECEPTOR. It possesses antinociceptive activity. | heterodetic cyclic peptide | delta-opioid receptor agonist |
| ci 988 | PD 134308: selective cholecystokinin type B receptor antagonist; inhibits growth of LoVo, a human colon cancer cell line; structure given in first source | ||
| l 740093 | L 740093: a CCK-B receptor antagonist; structure in first source | ||
| cholecystokinin 9 | cholecystokinin 9: nonapeptide | ||
| devazepide | devazepide : An indolecarboxamide obtained by formal condensation of the carboxy group of indole-2-carboxylic acid with the exocyclic amino group of (3S)-3-amino-1-methyl-5-phenyl-1,3-dihydro-1,4-benzodiazepin-2-one. A cholecystokinin antagonist used for treatment of gastrointestinal disorders. Devazepide: A derivative of benzodiazepine that acts on the cholecystokinin A (CCKA) receptor to antagonize CCK-8's (SINCALIDE) physiological and behavioral effects, such as pancreatic stimulation and inhibition of feeding. | 1,4-benzodiazepinone; indolecarboxamide | antineoplastic agent; apoptosis inducer; cholecystokinin antagonist; gastrointestinal drug |
| tetragastrin | tetragastrin : A tetrapeptide composed of L-tryptophan, L-methione, L-aspartic acid and L-phenylalaninamide residues joined in sequence. Tetragastrin: L-Tryptophyl-L-methionyl-L-aspartyl-L-phenylalaninamide. The C-terminal tetrapeptide of gastrin. It is the smallest peptide fragment of gastrin which has the same physiological and pharmacological activity as gastrin. | peptidyl amide; tetrapeptide | anxiogenic; human metabolite |
| cholecystokinin (26-33) | cholecystokinin (26-33): cholecystokinin receptor antagonists | ||
| cholecystokinin (27-33), tert-butyloxycarbonyl-nle(28,31)- | cholecystokinin (27-33), tert-butyloxycarbonyl-Nle(28,31)-: cholecystokinin agonist | ||
| 2-(2-(5-bromo-1h-indol-3-yl)ethyl)-3-(1-methylethoxyphenyl)-4-(3h)-quinazolinone | 2-(2-(5-bromo-1H-indol-3-yl)ethyl)-3-(1-methylethoxyphenyl)-4-(3H)-quinazolinone: CCK2 receptor antagonist | quinazolines | |
| l 365260 | L 365260: a CCK-B antagonist; structure given in first source; potent & selective CCK-B & gastrin receptor ligand; L 365260 and L 365346 are (R)- and (S)-stereoisomers, respectively | benzodiazepine | |
| enkephalin, ala(2)-mephe(4)-gly(5)- | peptide | ||
| sincalide | Sincalide: An octapeptide hormone present in the intestine and brain. When secreted from the gastric mucosa, it stimulates the release of bile from the gallbladder and digestive enzymes from the pancreas. | oligopeptide | |
| pentagastrin | Pentagastrin: A synthetic pentapeptide that has effects like gastrin when given parenterally. It stimulates the secretion of gastric acid, pepsin, and intrinsic factor, and has been used as a diagnostic aid. | organic molecular entity | |
| yf 476 | YF 476: gastrin and CCK-B receptor antagonist; structure in first source | ||
| l 365260 | |||
| mart-1 antigen | MART-1 Antigen: A melanosome-specific protein that plays a role in the expression, stability, trafficking, and processing of GP100 MELANOMA ANTIGEN, which is critical to the formation of Stage II MELANOSOMES. The protein is used as an antigen marker for MELANOMA cells. | ||
| 4-n-butyl-1-(4-(2-methylphenyl)-4-oxo-1-butyl)-piperidine hydrogen chloride | |||
| naluzotan | naluzotan: an antidepressant and anti-anxiety agent; structure in first source | ||
| butyloxycarbonyl-tryptophyl-methionyl-aspartyl-phenylalaninamide | |||
| gastrin 17 | gastrin-17 : One of the primary forms of gastrin that is a 17-membered peptide consisting of Glp, Gly, Pro, Trp, Leu, Glu, Glu, Glu, Glu, Glu, Ala, Tyr, Gly, Trp, Met, Asp and Phe-NH2 residues joined in sequence. | gastrin | antineoplastic agent |
| nitd 609 | NITD 609: an antimalarial and coccidiostat; structure in first source |