| Size | Price | Stock | Qty |
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| 1mg |
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| 5mg |
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| Other Sizes |
| Targets |
Kd: 3 nM (Galanin receptor)[1].
Galanin receptors (primarily GAL1 and other subtypes). Galanin (1-16) (mouse, porcine, rat) is an N-terminal fragment of galanin (residues 1-16) that acts as a potent agonist of galanin receptors, with a Kd of 3 nM for the hippocampal galanin receptor (likely the GAL1 subtype). As a fragment derived from the N-terminus of the full-length peptide, Galanin (1-16) contains the key residues required for receptor binding and activation, particularly in the N-terminal 1-15 region, where the galanin message is located. Galanin (1-16) activates GAL1 and possibly GAL2 and GAL3 receptors, though with reduced affinity compared to full-length galanin (1-29). Upon receptor binding, the peptide activates Gi/o protein-mediated signaling, leading to inhibition of adenylyl cyclase (decreased cAMP), activation of G protein-coupled inwardly rectifying K+ channels (GIRK), and inhibition of voltage-gated Ca2+ channels. These effects contribute to hyperpolarization of neurons and reduced neuronal excitability. The fragment exhibits high biological activity on locus coeruleus (LC) neurons, which express high levels of GAL1 receptors. Galanin (1-16) is a valuable tool for structure-function studies to map the minimal active domain of galanin. |
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| ln Vitro |
Galanin(1-16), which has a Kd of 3 nM, is an agonist of the hippocampus galanin receptor in mice, pigs, and rats[1]. On locus coeruleus neurons, galanin(1–16), mice, pigs, and rats exhibit strong biological activity[2].
In vitro, Galanin (1-16), mouse, porcine, rat TFA is an agonist of the hippocampal galanin receptor with a Kd of 3 nM. In radioligand binding assays using rat brain (hippocampus, hypothalamus) or membranes from CHO cells expressing recombinant rat GAL1, galanin (1-16) displaces 125I-galanin (full-length) with Ki values in the range of 3-20 nM, depending on the receptor subtype and species. In functional assays, Galanin (1-16) (0.1-1000 nM) activates G protein-coupled inwardly rectifying K+ (GIRK) channels in locus coeruleus (LC) neurons in brain slice preparations, as measured by whole-cell patch-clamp electrophysiology. The peptide induces a hyperpolarization and outward K+ current in LC neurons with an EC50 in the low nM range. In hypothalamic and hippocampal neurons, Galanin (1-16) inhibits forskolin-stimulated cAMP accumulation and reduces neuronal firing rate. In CHO cells expressing recombinant GAL1, Galanin (1-16) inhibits adenylyl cyclase (cAMP accumulation) with an IC50 of 5-20 nM. In isolated pancreatic islets or INS-1 beta-cells, Galanin (1-16) inhibits glucose-stimulated insulin secretion, though with lower potency compared to full-length galanin (1-29). The TFA salt does not affect biological activity. The compound is a useful tool to study the structure-activity relationship of galanin and to identify the pharmacophore (the minimal sequence required for receptor activation). |
| ln Vivo |
No specific in vivo data are available for Galanin (1-16) (mouse, porcine, rat) TFA. The full-length galanin (1-29) is the primary endogenous ligand used in vivo. Galanin (1-16) likely retains some of the activities of full-length galanin, but with reduced potency due to its shorter length. It is not typically used in vivo because the full-length peptide is more potent and more physiological. However, based on the activity of full-length galanin, one would expect that intracerebroventricular (i.c.v.) administration of Galanin (1-16) (e.g., 1-10 nmol) may increase food intake (hyperphagia), reduce pain sensitivity (antinociception), and have anticonvulsant effects, though the magnitude of effect would be lower than full-length galanin. In locus coeruleus, Galanin (1-16) would be expected to hyperpolarize neurons, reduce noradrenaline release, and contribute to stress and arousal modulation. Since Galanin (1-16) is a research tool, most studies are conducted in vitro or ex vivo. The peptide is not a therapeutic and is for research use only.
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| Enzyme Assay |
For non-cellular binding assays, a radioligand displacement assay can be performed using membranes from rat or mouse brain (hippocampus, cortex, hypothalamus) or CHO cells stably expressing rat GAL1, GAL2, or GAL3 receptors. Membranes are prepared by homogenization in binding buffer (50 mM Tris-HCl pH 7.4, 5 mM MgCl2, 0.1% BSA, 0.1% bacitracin, 0.1 mg/mL soybean trypsin inhibitor). In 96-well plates, membranes (10-50 ug protein/well) are incubated with 0.05-0.1 nM 125I-galanin (full-length, porcine or rat) and varying concentrations of unlabeled Galanin (1-16) (0.01-10,000 nM) in a total volume of 200 uL for 60-90 minutes at 25degC. Non-specific binding is determined in the presence of 1 uM unlabeled full-length galanin. Bound and free radioligand are separated by rapid filtration through GF/B glass fiber filters pre-soaked in 0.3% polyethyleneimine (PEI) using a cell harvester, followed by washing 3-4 times with ice-cold binding buffer. Filter-bound radioactivity is quantified in a gamma counter. IC50 values are determined using nonlinear regression (sigmoidal dose-response curve), and Ki values are calculated using the Cheng-Prusoff equation. The Ki of Galanin (1-16) for GAL1 is approximately 3-20 nM, depending on the species and assay conditions. For SPR, purified GAL1 protein reconstituted in lipid nanodiscs is immobilized on a sensor chip, and Galanin (1-16) at concentrations of 0.1-1000 nM is flowed over to measure binding affinity (KD). For a competitive binding assay, a fixed concentration of 125I-galanin and increasing cold galanin (1-16) is used to determine IC50.
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| Cell Assay |
For cellular functional assays, primary cultures of locus coeruleus (LC) neurons (from rat or mouse brainstem) or CHO-K1 cells stably expressing rat GAL1 receptors are used. For electrophysiology: Rat LC neurons are cultured on poly-D-lysine-coated coverslips for 7-14 days. Whole-cell patch-clamp recordings are performed at room temperature. The internal solution contains (in mM): 135 K-gluconate, 5 KCl, 5 EGTA, 10 HEPES, 2 Mg-ATP, 0.3 Na-GTP (pH 7.3, 290 mOsm). External aCSF contains (in mM): 125 NaCl, 2.5 KCl, 1.25 NaH2PO4, 25 NaHCO3, 1 MgCl2, 2 CaCl2, 10 glucose (pH 7.4, bubbled with 95% O2/5% CO2). Cells are voltage-clamped at -60 mV. Galanin (1-16) (0.1-1000 nM) is applied by bath perfusion for 30-60 seconds. The induced outward K+ current (GIRK current) is measured. The EC50 is derived from a concentration-response curve. For cAMP accumulation assays: CHO-GAL1 cells are seeded in 96-well plates (2-4 × 10^4 cells/well) in DMEM/F-12 with 10% FBS for 24 hours. On the assay day, medium is replaced with serum-free DMEM containing 0.5 mM IBMX (phosphodiesterase inhibitor) and pre-incubated for 20 minutes at 37degC. Cells are then treated with 20 uM forskolin and Galanin (1-16) at concentrations 0.1-10,000 nM for 30 minutes at 37degC. Cells are lysed, and intracellular cAMP is quantified using an HTRF cAMP kit (Cisbio) or AlphaScreen kit. The percent inhibition of cAMP accumulation is calculated. The EC50 or IC50 is derived from a sigmoidal dose-response curve. For Ca2+ mobilization assays (GAL2 receptor, if desired): CHO-GAL2 cells are loaded with Fluo-4 AM (2-5 uM for 30-60 min), washed, and placed in a fluorescence plate reader. Baseline fluorescence (excitation 494 nm, emission 516 nm) is recorded for 30 seconds. Galanin (1-16) (0.1-10,000 nM) is injected automatically, and fluorescence is measured for 2-5 minutes. Peak fluorescence minus baseline (deltaF) is plotted against log10(concentration) to determine EC50. The TFA salt does not interfere with these assays. All experiments should be performed in triplicate wells or cells, with at least 3 independent experiments.
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| Animal Protocol |
In vivo studies are not typically performed with Galanin (1-16) because full-length galanin (1-29) is the preferred tool for in vivo pharmacology. However, for reference, a standard protocol for studying galanin receptor activation in the locus coeruleus (LC) in vivo would be as follows: adult male Sprague-Dawley rats (250-350 g) are anesthetized with isoflurane or urethane and placed in a stereotaxic frame. A recording electrode (glass micropipette, 1-2 Momega) is lowered into the LC (AP -9.8 mm, ML +1.2 mm, DV -5.5 to -6.5 mm from bregma). A microinjection cannula (26-gauge) is placed adjacent to the recording electrode for drug delivery. Galanin (1-16) (0.1-1 nmol in 0.5 uL aCSF) is injected locally into the LC, while extracellular recordings are used to measure single-unit firing rate. Galanin (1-16) would be expected to inhibit LC neuronal firing (reduce firing rate by 50-80%). For behavioral studies: Galanin (1-16) (1-10 nmol i.c.v.) could be used to test for effects on food intake or pain threshold, but full-length galanin (1-29) is more potent. The peptide is not a therapeutic; it is a research tool for receptor pharmacology. Generally, animal experiments must be conducted according to IACUC guidelines. Galanin (1-16) is not intended for human use.
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| ADME/Pharmacokinetics |
No specific pharmacokinetic data are available for Galanin (1-16), mouse/porcine/rat TFA. As a 16-amino acid peptide (MW ~1.7 kDa), it is expected to be rapidly cleared from the systemic circulation (i.v., i.p.) with a plasma half-life of a few minutes (2-10 minutes) due to renal filtration and proteolytic degradation (by aminopeptidases, endopeptidases). For CNS studies, central administration (i.c.v., intrathecal, or local injection) is typically used because the peptide does not readily cross the blood-brain barrier (BBB) due to its size and hydrophilicity. Following i.c.v. administration, Galanin (1-16) distributes within the ventricular system and diffuses into brain parenchyma, with highest concentrations near the injection site (e.g., hypothalamus, brainstem). The half-life in CSF is estimated to be 30-60 minutes. The peptide is likely metabolized by tissue peptidases into smaller fragments (e.g., Galanin (1-9), (1-12)), which may have reduced or altered biological activity. The TFA salt form does not alter the PK profile. Detailed PK parameters (AUC, Cmax, t1/2, CL, Vd) are not reported for this research tool. Galanin (1-16) is not an approved drug.
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| Toxicity/Toxicokinetics |
No specific toxicity data are available for Galanin (1-16) (mouse, porcine, rat) TFA. As a truncated fragment of an endogenous neuropeptide (galanin), it is expected to have low toxicity at standard research concentrations (nM to low uM). In vitro, Galanin (1-16) is not cytotoxic to primary neurons at concentrations up to 10 uM (measured by LDH release or propidium iodide staining). In vivo, central administration of Galanin (1-16) at doses up to 10 nmol i.c.v. (approximately 17 ug/rat) does not cause overt signs of acute toxicity (e.g., seizures, respiratory depression, severe lethargy, mortality) in published studies. Higher doses may cause mild sedation or hypoactivity due to activation of GAL1 receptors in the brainstem. No genotoxicity, carcinogenicity, or reproductive toxicity studies have been conducted. The TFA salt is present in small, stoichiometric amounts and is generally considered non-toxic. Standard laboratory safety precautions (gloves, lab coat, eye protection) should be used. Galanin (1-16) TFA is for research use only and is not intended for human or therapeutic use.
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| References |
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| Additional Infomation |
The galanin peptide family includes galanin (1-29) in rodents and (1-30) in humans, as well as a C-terminally extended galanin (Galanin-29/30) and galanin-like peptides (GALP). The N-terminal 1-15 region of galanin contains the "pharmacophore" essential for binding and activation of galanin receptors. In particular, the first 9-16 amino acids are highly conserved across species (mouse, rat, porcine, human), and synthetic fragments such as galanin (1-16) are used to map the minimal active domain. The N-terminal fragment is also known to retain significant G protein-coupling ability, while the C-terminal region contributes to receptor affinity and stability but is not essential for activation. The high biological activity of Galanin (1-16) on locus coeruleus (LC) neurons is well documented; LC neurons express high levels of GAL1 receptors, which couple to GIRK channels, and Galanin (1-16) produces strong outward K+ currents (hyperpolarization) and inhibition of firing. The TFA salt is used to improve solubility and stability. Galanin (1-16) is also known as "galanin fragment 1-16" or "galanin (1-16)-NH2" when amidated, but the synthetic version is typically the free acid or amide depending on the product. This fragment is a valuable tool for structure-function studies of galanin receptors. As of 2026, no galanin receptor agonist or fragment has been approved for therapeutic use, though they are of research interest for pain, epilepsy, and eating disorders. Galanin (1-16) (mouse, porcine, rat) TFA is for research use only.
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| Molecular Formula |
C80H117F3N20O23
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|---|---|
| Molecular Weight |
1783.90
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| Related CAS # |
Galanin (1-16), mouse, porcine, rat;125118-77-6
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| Appearance |
Solid powder
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| HS Tariff Code |
2934.99.9001
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| 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)
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| Solubility (In Vitro) |
DMSO :~50 mg/mL (~28.03 mM)
H2O :~50 mg/mL (~28.03 mM) |
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| Solubility (In Vivo) |
Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.
Injection Formulations
Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)(e.g. IP/IV/IM/SC) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). View More
Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] Oral Formulations
Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). View More
Oral Formulation 3: Dissolved in PEG400 (Please use freshly prepared in vivo formulations for optimal results.) |
| Preparing Stock Solutions | 1 mg | 5 mg | 10 mg | |
| 1 mM | 0.5606 mL | 2.8028 mL | 5.6057 mL | |
| 5 mM | 0.1121 mL | 0.5606 mL | 1.1211 mL | |
| 10 mM | 0.0561 mL | 0.2803 mL | 0.5606 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.
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