| Size | Price | Stock | Qty |
|---|---|---|---|
| 1mg |
|
||
| 5mg |
|
||
| Other Sizes |
| Targets |
Cholecystokinin B receptor (CCK-BR, also known as CCK2 receptor or gastrin receptor). Gastrin I (1-14) is an N-terminal fragment of gastrin-17 (the major circulating form of human gastrin). The biological activity of gastrin is mediated through binding to the cholecystokinin B receptor (CCK-BR/CCK2R), a class A GPCR that is highly expressed on gastric parietal cells and enterochromaffin-like (ECL) cells, as well as in the brain and pancreas. Upon binding, gastrin activates Gq protein, leading to phospholipase C activation, IP3 generation, and Ca2+ mobilization, ultimately stimulating gastric acid secretion and promoting growth of the gastric mucosa. The 1-14 fragment contains the important N-terminal residues involved in receptor binding, though full-length gastrin is required for full biological potency. The TFA salt improves peptide stability.
|
|---|---|
| ln Vitro |
In vitro, Gastrin I (1-14) (human TFA) is the 1-14 fragment of human gastrin I peptide. While the full-length gastrin-17 is the major circulating and biologically active form, the 1-14 fragment retains some ability to bind to the CCK2/gastrin receptor. In CCK2R-expressing cells (e.g., CHO-CCK2R, AR42J pancreatic acinar cells), the 1-14 fragment induces intracellular Ca2+ mobilization, though with lower potency compared to gastrin-17. The fragment stimulates inositol phosphate accumulation and activates MAPK/ERK signaling in gastric cell lines. It is also used in receptor binding studies to map the minimal gastrin sequence required for CCK2R recognition. In isolated rabbit or rat gastric glands, Gastrin I (1-14) (1-100 nM) stimulates acid secretion measured by 14C-aminopyrine accumulation, with efficacy lower than gastrin-17. In some cell-based assays, it may act as a partial agonist or weaker full agonist depending on the system.
|
| ln Vivo |
No specific in vivo data are available for Gastrin I (1-14), human TFA. The full-length gastrin-17 (e.g., pentagastrin, which is a synthetic C-terminal tetrapeptide analog) is used in vivo to stimulate gastric acid secretion, while the 1-14 fragment is typically used as a research tool in vitro. In animal models, intravenous infusion of gastrin-17 (0.1-10 ug/kg/h) stimulates gastric acid output, increases gastric mucosal blood flow, and promotes growth of the gastric mucosa (trophic effect). Gastrin I (1-14) would be expected to have reduced potency compared to gastrin-17 due to its shorter length. The peptide is not used as a therapeutic; instead, gastrin receptor antagonists have been explored for the treatment of gastroesophageal reflux disease (GERD) and gastrin-secreting tumors (Zollinger-Ellison syndrome).
|
| Enzyme Assay |
For direct binding assays, a radioligand binding assay using CCK2/gastrin receptor-rich membranes is performed. Membranes from CHO-CCK2R cells (or rat gastric fundus/pancreas) are prepared by homogenization in binding buffer (10 mM HEPES pH 7.4, 130 mM NaCl, 5 mM MgCl2, 1 mM EGTA, 0.2% BSA, 0.02% bacitracin). Membrane protein (10-50 ug/well) is incubated with 0.05-0.1 nM 125I-gastrin-17 (or 3H-pentagastrin) and varying concentrations of Gastrin I (1-14) (0.1-10,000 nM) in 96-well plates for 60 minutes at 25degC. Non-specific binding is determined in the presence of 1 uM unlabeled gastrin-17. Bound and free radioligand are separated by rapid filtration through GF/B filters pre-soaked in 0.3% PEI, followed by washing with ice-cold binding buffer. Radioactivity on filters is quantified. IC50 values are converted to Ki using the Cheng-Prusoff equation. For SPR, CCK2R can be immobilized on a sensor chip, and Gastrin I (1-14) is flowed over at varying concentrations to determine KD. The 1-14 fragment may show reduced affinity relative to gastrin-17.
|
| Cell Assay |
For cellular functional assays, CHO-K1 cells stably expressing human CCK2/gastrin receptor (CHO-CCK2R) are seeded in 96-well plates at 2-4 × 10^4 cells/well in DMEM with 10% FBS and incubated for 24 hours at 37degC, 5% CO2. On the assay day, cells are loaded with Fluo-4 AM (2-5 uM in HBSS with 0.02% Pluronic F-127 and 2.5 mM probenecid) for 30-60 minutes at 37degC. After loading, cells are washed twice with HBSS and 100 uL/well of HBSS containing 0.1% BSA is added. The plate is placed in a fluorescence plate reader (e.g., FlexStation 3, FLIPR Tetra). Baseline fluorescence (excitation 494 nm, emission 516 nm) is recorded for 20-30 seconds. Gastrin I (1-14) is diluted in HBSS (0.1-10,000 nM) and automatically injected, and fluorescence is measured for 2-5 minutes. The peak fluorescence minus baseline (deltaF) is plotted against log10(concentration) to generate a concentration-response curve, and EC50 is determined. For inositol phosphate (IP) accumulation assays, cells are labeled with 3H-myo-inositol, stimulated with Gastrin I (1-14) (0.1-10,000 nM) for 30-60 minutes in the presence of 10 mM LiCl, and IPs are separated by anion-exchange chromatography and quantified by liquid scintillation counting. The 1-14 fragment may act as a weaker agonist compared to gastrin-17 and can be used to study partial agonism and structure-activity relationships.
|
| Animal Protocol |
In vivo studies are not typically conducted with Gastrin I (1-14), human TFA. For reference, pentagastrin (a synthetic C-terminal tetrapeptide, Boc-beta-Ala-Trp-Met-Asp-Phe-NH2) is a full agonist of the gastrin/CCK2 receptor that has been used in vivo for gastric acid secretion tests (e.g., "pentagastrin test"). In a typical in vivo protocol, rats or dogs are anesthetized, and gastric acid secretion is measured by gastric cannulation or by collecting gastric fluid via an indwelling gastric tube. Pentagastrin (6-12 ug/kg) is administered by subcutaneous or intramuscular injection, and gastric acid output (volume and pH) is measured for 60-90 minutes post-injection. Pentagastrin is also used to induce mucosal growth and to model hypergastrinemia. However, Gastrin I (1-14) is not commonly used in vivo due to its lower potency and limited availability. The fragment is primarily a research tool for in vitro and ex vivo studies.
|
| ADME/Pharmacokinetics |
No specific pharmacokinetic data are available for Gastrin I (1-14), human TFA. The full-length gastrin-17 has a short plasma half-life in humans (approximately 2-5 minutes) due to rapid enzymatic degradation (by neutral endopeptidases, including neprilysin/NEP) and renal clearance. The 1-14 fragment would be expected to have similar or even faster clearance because it is smaller and more susceptible to proteolysis. The TFA salt (trifluoroacetate) is a common counterion for peptide stabilization during lyophilization and storage, but it does not significantly influence in vivo pharmacokinetics. Gastrin fragments (e.g., pentagastrin) have been used clinically as diagnostic agents. Gastrin I (1-14) is not used as a therapeutic; it is a research tool.
|
| Toxicity/Toxicokinetics |
No specific toxicity data are available for Gastrin I (1-14), human TFA. As a fragment of an endogenous hormone, it is expected to have low toxicity at standard research concentrations. The full-length gastrin-17, at supraphysiological doses in animals, can cause transient hypotension, flushing, nausea, vomiting, and diarrhea due to increased gastric acid secretion and smooth muscle contraction. Chronic hypergastrinemia (elevated gastrin levels) is associated with hyperplasia and potential neoplastic transformation of gastric enterochromaffin-like (ECL) cells, leading to gastric carcinoid tumors in rodents, but this is a long-term trophic effect, not acute toxicity. The TFA salt is present in small, stoichiometric amounts and is generally considered non-toxic. Gastrin I (1-14) is for research use only and is not intended for human or therapeutic applications. Standard laboratory safety precautions should be followed.
|
| References |
[1]. Jordan PH Jr, et al. Physiology of gastrin. Am J Surg. 1969 Jun;117(6):822-30.
|
| Additional Infomation |
Gastrin is a linear peptide hormone with key functional residues at the C-terminus (the tetrapeptide Trp-Met-Asp-Phe-NH2) which contains the minimal sequence required for receptor activation and biological activity (CCK2/gastrin receptor). The N-terminal 1-14 region of human gastrin I is less critical for receptor activation but influences affinity, stability, and may contribute to tissue-specific effects. The full-length gastrin I (1-17) has the sequence Glp-Gly-Pro-Trp-Leu-Glu-Glu-Glu-Glu-Glu-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2, with pyroglutamyl (Glp) at the N-terminus and an amidated C-terminus. Gastrin I (1-14), human TFA is the N-terminal 1-14 fragment (Glp-Gly-Pro-Trp-Leu-Glu-Glu-Glu-Glu-Glu-Ala-Tyr-Gly-Trp-OH). This fragment is used for structure-function studies to map the contributions of individual amino acids to receptor binding, intracellular signaling, and biological activity. The TFA salt is used to improve peptide handling and stability. Gastrin I (1-14) is not a drug; it is a research-grade biochemical reagent.
|
| Molecular Formula |
C81H101N16F3O29
|
|---|---|
| Molecular Weight |
1819.75
|
| Related CAS # |
Gastrin I (1-14), human;100940-57-6
|
| Appearance |
White to off-white solid powder
|
| HS Tariff Code |
2934.99.9001
|
| Storage |
Powder -20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light. |
| Shipping Condition |
Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)
|
| Solubility (In Vitro) |
DMSO :≥ 100 mg/mL (~54.95 mM)
H2O :~100 mg/mL (~54.95 mM) |
|---|---|
| Solubility (In Vivo) |
Solubility in Formulation 1: 100 mg/mL (54.95 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication.
(Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 0.5495 mL | 2.7476 mL | 5.4953 mL | |
| 5 mM | 0.1099 mL | 0.5495 mL | 1.0991 mL | |
| 10 mM | 0.0550 mL | 0.2748 mL | 0.5495 mL |
*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.
Calculation results
Working concentration： mg/mL；
Method for preparing DMSO stock solution： mg drug pre-dissolved in μL DMSO (stock solution concentration mg/mL). Please contact us first if the concentration exceeds the DMSO solubility of the batch of drug.
Method for preparing in vivo formulation:：Take μL DMSO stock solution, next add μL PEG300, mix and clarify, next addμL Tween 80, mix and clarify, next add μL ddH2O，mix and clarify.
(1) Please be sure that the solution is clear before the addition of next solvent. Dissolution methods like vortex, ultrasound or warming and heat may be used to aid dissolving.
(2) Be sure to add the solvent(s) in order.
Products are for research use only; We do not sell to patients
Copyright 2020 InvivoChem LLC | All Rights Reserved
