Dynorphin A TFA is an endogenous opioid peptide involved in inhibitory neurotransmission in the central nervous system/CNS. Dynorphin A TFA is a potent agonist of the kappa opioid receptor (KOR) and other opioid receptors such as mu (MOR) and delta (DOR). Dynorphin A TFA can induce neuronal death and may be utilized in research related to neurological diseases.

Physicochemical Properties

Molecular Formula	C101H156F3N31O25
Molecular Weight	2261.50
Related CAS #	Dynorphin A;80448-90-4
Appearance	Typically exists as solid at room temperature
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
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

Targets	Human Endogenous Metabolite Caspase-3 κ Opioid Receptor/KOR
ln Vitro	In mouse striatal neurons, dynorphin A TFA (10 μM, 4 h/72 h) increases the amount of cytochrome c released from mitochondria and caspase-3 activity, which results in neuronal death[3]. Neurons are significantly lost and [Ca2+]i is elevated at 33 μM for 4 hours when dynorphin A TFA is administered[4]. The release of vasopressin (VP) from the isolated neural lobe is inhibited by dynorphin A TFA (1 μM)[5].
ln Vivo	Male rats denied of water for 24 hours and are given 1 μg or 2 μL of dynorphin A TFA intracerebroventricular injection as a single dose, which decreases the release of vasopressin (VP)[5]. Intracerebroventricular injection of dynorphin A TFA (500 pmol/5 μL daily for 4 days) reduces behavioral deficits in ddY mice caused by stress, together with brain modulation of the 5-HTergic system[6].
Cell Assay	Cell Viability Assay[3] Cell Types: Mouse Striatal neurons Tested Concentrations: 10 μM Incubation Duration: 0, 24, 48, 72 h Experimental Results: Induced neuronal death (identified by the fragmentation and destruction of the cell body and neurites).
Animal Protocol	Animal/Disease Models: 24 h water-deprived male rats[5] Doses: 1 μg of 2 μL Route of Administration: Intracerebroventricular injection Experimental Results: Inhibited vasopressin (VP) release 30 min upon injection. Animal/Disease Models: Male ddY mice[6] Doses: 15, 150, 1500 pmol/5 μL per day for 4 days Route of Administration: Intracerebroventricular injection Experimental Results: Attenuated the repeated stress -induced escape failures from the shock.
References	[1]. Dynorphin A as a Potential Endogenous Ligand for Four Members of the Opioid Receptor Gene Family. J Pharmacol Exp Ther. 1998 Jul;286(1):136-41. [2]. Monoclonal antibodies as novel neurotherapeutic agents in CNS injury and repair. Int Rev Neurobiol. 2012;102:23-45. [3]. Dynorphin A (1–17) induces apoptosis in striatal neurons in vitro through AMPA/kainate receptor-mediated cytochrome c release and caspase-3 activation. Neuroscience. 2003;122(4):1013-23. [4]. Dynorphin-A and vasopressin release in the rat: a structure-activity study. Neuropeptides. 1994 Jun;26(6):371-8. [5]. Dynorphin a (1-13) alleviated stress-induced behavioral impairments in mice. Biol Pharm Bull. 2014;37(8):1269-73. [6]. Dynorphin A (1-13) neurotoxicity in vitro: opioid and non-opioid mechanisms in mouse spinal cord neurons. Exp Neurol. 1999 Dec;160(2):361-75.

Solubility Data

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 (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *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). 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)] *Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL 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). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	0.4422 mL	2.2109 mL	4.4218 mL
	5 mM	0.0884 mL	0.4422 mL	0.8844 mL
	10 mM	0.0442 mL	0.2211 mL	0.4422 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.