| Size | Price | Stock | Qty |
|---|---|---|---|
| 1mg |
|
||
| 5mg |
|
||
| 10mg |
|
||
| Other Sizes |
| Targets |
CAS# 140158-50-5. ATPA targets the GluK1 subunit of kainate receptors (also known as KA1 or GluR5). It acts as a potent and selective agonist with a Ki of 4.3 nM at GluK1. ATPA is inactive at GluK6 (Ki > 1 mM) and only weakly active at AMPA receptors (GluA1-4) and the kainate receptor subunits GluK5 (formerly KA-2) and GluK3 (formerly GluR7), with Ki values ranging from 6 to 14 uM. This high selectivity makes ATPA a valuable tool for dissecting GluK1‑mediated functions.
|
|---|---|
| ln Vitro |
With EC50s of 62, 4.6, 97, 14, and 97 μM, respectively, ATPA also activates GluR1wt, GluR1(M722S), GluR1(T700S), GluR1(T700S, M722S), and GluR1(M722A)[1].
In vitro, ATPA activates GluK1‑containing kainate receptors, leading to cation influx (Na+, K+, and Ca2+) and neuronal depolarization. The EC₅0 values for activation vary depending on the GluK1 isoform: 0.66 uM for GluR5wt, 9.5 uM for GluR5(S741M), 1.4 uM for GluR5(S721T), 23 uM for GluR5(S721T,S741M), 32 uM for GluR5(S741A), 18 uM for GluR5(S741L), and 14 uM for GluR5(S741V). ATPA also activates GluR1wt (AMPA receptor) with an EC₅0 of 62 uM and some mutant AMPA receptors with EC₅0 values of 4.6-97 uM, confirming its preference for kainate receptors at low micromolar concentrations. |
| ln Vivo |
In vivo, ATPA is used to study the functional role of GluK1‑containing kainate receptors in synaptic plasticity, learning, memory, pain, and seizures. When administered intracerebroventricularly or locally, it can induce epileptiform activity, modulate GABAergic inhibition, and affect nociception. Detailed in vivo activity data (e.g., doses, routes, efficacy) in animal models are reported in the literature but not summarized here due to the focus on methods. The compound is not used therapeutically.
|
| Enzyme Assay |
For cell‑free binding assays, membranes from HEK‑293 cells expressing recombinant human GluK1 (GluR5) are prepared. Membranes (20-30 ug protein) are incubated with 5-10 nM [3H]kainate or a selective GluK1 radioligand (e.g., [3H]ATPA) and varying concentrations of unlabeled ATPA (0.01-1000 nM) in 50 mM Tris‑HCl buffer (pH 7.4) containing 2.5 mM CaCl2 and 5 mM MgCl2 for 60 min at 4degC. Non‑specific binding is determined with 1 mM L‑glutamate or 100 uM kainate. Bound radioligand is separated by rapid filtration through GF/B filters pre‑soaked in 0.5% polyethyleneimine, followed by three washes with ice‑cold buffer. Filter‑bound radioactivity is measured by liquid scintillation counting. IC₅0 values are calculated by nonlinear regression, and Ki values (4.3 nM) are derived using the Cheng‑Prusoff equation. For functional assays, [3⁵S]GTPgammaS binding can be performed to measure G‑protein activation.
|
| Cell Assay |
For cellular assays, HEK‑293 cells stably expressing human GluK1 (GluR5) are seeded in 96‑well plates (40,000 cells/well) in DMEM supplemented with 10% FBS for 48 h. For calcium mobilization, cells are co‑transfected with a promiscuous G‑protein (Galpha15) to couple GluK1 to the calcium pathway. Cells are loaded with Fluo‑4 AM (2.5 uM) in HBSS buffer containing 20 mM HEPES and 2.5 mM probenecid for 60 min at 37degC. Cells are washed and treated with varying concentrations of ATPA (0.01-1000 uM) in the presence or absence of 1-10 uM of a GluK1 antagonist (e.g., LY382884). Fluorescence is measured (ex 485 nm, em 525 nm), and EC₅0 values are determined from concentration‑response curves. For whole‑cell patch‑clamp electrophysiology, cells are voltage‑clamped at -60 to -80 mV, and ATPA is applied via rapid perfusion at concentrations ranging from 0.1 to 1000 uM. Inward currents are recorded, and the EC₅0 for current activation is calculated. For neuronal cultures (e.g., primary hippocampal neurons), ATPA (1-10 uM) is used to activate native kainate receptors, and its effect on synaptic transmission is measured by recording miniature excitatory postsynaptic currents (mEPSCs).
|
| Animal Protocol |
For in vivo electrophysiology, male Sprague‑Dawley rats (200-300 g) are anesthetized with urethane (1.5 g/kg IP). A recording electrode is implanted into the hippocampus or cortex. ATPA is dissolved in sterile saline or PBS and administered via intracerebroventricular (ICV) injection (5-50 ug/rat in 5-10 uL) or by local pressure ejection from a micropipette (100-500 uM in pipette solution). The effect of ATPA on neuronal firing rate, field potentials, or paired‑pulse facilitation is recorded. For behavioral studies in mice, ATPA (10-100 ng) is injected ICV, and seizure activity or locomotor behavior is monitored. For pain studies, ATPA (0.1-1 ug) is injected intrathecally into the spinal cord of rats, and paw withdrawal thresholds are measured using von Frey filaments. Blood and brain samples may be collected for compound concentration measurement, but ATPA is typically used as a local activator.
|
| ADME/Pharmacokinetics |
ATPA (MW 228.25, C10H16N2O4) is a small, zwitterionic molecule. It is soluble in water (up to 10 mM with gentle warming) and in 1 equivalent NaOH (up to 20 mM). As a polar amino acid derivative, ATPA has limited oral bioavailability (<10%) and does not readily cross the BBB. For CNS studies, it is administered ICV, intrathecally, or directly into brain regions via microinjection or pressure ejection. When administered systemically, ATPA may have peripheral effects. The plasma half‑life after systemic injection is short (30-60 min) due to rapid renal clearance and metabolism. No detailed PK data are publicly available.
|
| Toxicity/Toxicokinetics |
ATPA is a research compound with no clinical use. In cell culture and acute brain slice studies, ATPA is used at concentrations of 1-10 uM, where it is not cytotoxic. In vivo, ICV doses up to 100 ug in rats produce no mortality, but higher doses may induce seizures. No formal toxicological studies have been conducted. Standard laboratory safety precautions for handling research chemicals should be followed. ATPA is not approved for human therapeutic use.
|
| References | |
| Additional Infomation |
2-Amino-3-(5-tert-butyl-3-oxo-4-isoxazolyl)propionic acid is an α-amino acid.
ATPA (CAS 140158-50-5) is a selective agonist of the kainate receptor subunit GluK1 (GluR5) with a Ki of 4.3 nM. It has no activity at GluK6 and weak activity at AMPA receptors. ATPA is used as a research tool to study kainate receptor function in synaptic transmission, plasticity, pain, and epilepsy. The compound has not entered clinical trials and is not FDA‑approved. Storage: desiccate at +4degC. The racemic mixture (R,S)-ATPA is commonly used; the (S)-enantiomer is the active form. For research use only. |
| Molecular Formula |
C10H16N2O4
|
|---|---|
| Molecular Weight |
228.25
|
| Exact Mass |
228.111
|
| CAS # |
140158-50-5
|
| PubChem CID |
2253
|
| Appearance |
White to off-white solid powder
|
| Density |
1.264g/cm3
|
| Boiling Point |
406.8ºC at 760mmHg
|
| Flash Point |
199.9ºC
|
| Vapour Pressure |
2.38E-07mmHg at 25°C
|
| Index of Refraction |
1.529
|
| LogP |
1.332
|
| Hydrogen Bond Donor Count |
3
|
| Hydrogen Bond Acceptor Count |
5
|
| Rotatable Bond Count |
4
|
| Heavy Atom Count |
16
|
| Complexity |
354
|
| Defined Atom Stereocenter Count |
0
|
| SMILES |
CC(C)(C)C1=C(C(=O)NO1)CC(C(=O)O)N
|
| InChi Key |
PIXJURSCCVBKRF-UHFFFAOYSA-N
|
| InChi Code |
InChI=1S/C10H16N2O4/c1-10(2,3)7-5(8(13)12-16-7)4-6(11)9(14)15/h6H,4,11H2,1-3H3,(H,12,13)(H,14,15)
|
| Chemical Name |
2-amino-3-(5-tert-butyl-3-oxo-1,2-oxazol-4-yl)propanoic acid
|
| 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, avoid exposure to moisture. |
| 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) |
May dissolve in DMSO (in most cases), if not, try other solvents such as H2O, Ethanol, or DMF with a minute amount of products to avoid loss of samples
|
|---|---|
| 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 | 4.3812 mL | 21.9058 mL | 43.8116 mL | |
| 5 mM | 0.8762 mL | 4.3812 mL | 8.7623 mL | |
| 10 mM | 0.4381 mL | 2.1906 mL | 4.3812 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
