Brevetoxin-3 (PbTx-3) is a potent allosteric voltage-gated Na+ channel activator with multiple active centers (A ring lactone, R side chain C-42). Brevetoxin-3 (PbTx-3) has high affinity for site 5 of voltage-sensitive Na+ channels, inhibiting the inactivation of Na+ channels and prolonging the mean open time of these channels. Brevetoxin-3 (PbTx-3) causes prolonged airway hyperresponsiveness (AHR) and lung inflammation.

Physicochemical Properties

Molecular Formula	C₅₀H₇₂O₁₄
Molecular Weight	897.10
Exact Mass	896.492
CAS #	85079-48-7
PubChem CID	5353448
Appearance	White to off-white solid powder
Density	1.187g/cm3
Index of Refraction	1.52
LogP	5.265
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	14
Rotatable Bond Count	3
Heavy Atom Count	64
Complexity	1910
Defined Atom Stereocenter Count	0
SMILES	CC1CC2C(CC3(C(O2)CC4C(O3)C(=CC(=O)O4)C)C)OC5C1OC6CC7C(CC8C(O7)(C/C=C\C9C(O8)CC1C(O9)CC2C(O1)(C(CC(O2)CC(=C)CO)O)C)C)(OC6(CC5)C)C
InChi Key	BKMHDYJRAAJTAD-KTKRTIGZSA-N
InChi Code	InChI=1S/C50H72O14/c1-25(24-51)14-28-17-37(52)50(8)41(54-28)19-33-34(61-50)18-32-29(55-33)10-9-12-46(4)42(58-32)23-49(7)40(62-46)21-39-47(5,64-49)13-11-30-44(60-39)26(2)15-31-36(56-30)22-48(6)38(57-31)20-35-45(63-48)27(3)16-43(53)59-35/h9-10,16,26,28-42,44-45,51-52H,1,11-15,17-24H2,2-8H3/b10-9-
Chemical Name	(21Z)-12-hydroxy-14-[2-(hydroxymethyl)prop-2-enyl]-1,3,11,24,31,41,44-heptamethyl-2,6,10,15,19,25,29,34,38,43,47-undecaoxaundecacyclo[26.22.0.03,26.05,24.07,20.09,18.011,16.030,48.033,46.035,44.037,42]pentaconta-21,40-dien-39-one
Synonyms	Brevetoxin3; Brevetoxin 3
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

ln Vitro	Single channel activity is detected under steady-state circumstances (maintaining depolarization at -50 mV) due to a shift in activation to a more negative membrane potential caused by brevetoxin-3 (PbTx-3) (30-500 nM) [1].
ln Vivo	Brevetoxin-3 (PbTx-3) (2.8 μg/kg intratracheal instillation; gestation days 15–18) Within an hour, radioactivity was found in the fetus and placenta. The estimated fetal dose of 19 ng/gh was determined by measuring the fetal equivalent concentration of brachytoxin 48 hours after injection, which was roughly 0.3 ng/g. The fetus has an equivalent brachytoxin concentration of 0.1 ng/g following brachytoxin infusion, which is less than the concentration in the majority of maternal tissues [3].
Animal Protocol	Animal/Disease Models: Pregnant CD-1 mice [3] Doses: 2.8 μg/kg Route of Administration: Intratracheal instillation; 2.8 μg/kg; Pregnancy days 15-18 Experimental Results: Confirmed placental transmission of short-term infection after acute maternal exposure tail toxin or its metabolites.
References	[1]. Brevetoxin-3 (PbTx-3) and its derivatives modulate single tetrodotoxin-sensitive sodium channels in rat sensory neurons.J Pharmacol Exp Ther. 1998 Feb;284(2):516-25. [2]. Repeated exposure to aerosolized brevetoxin-3 induces prolonged airway hyperresponsiveness and lung inflammation in sheep.Inhal Toxicol. 2011 Mar;23(4):205-11. [3]. Placental transport of brevetoxin-3 in CD-1 mice.Toxicon. 2006 Dec 15;48(8):1018-26. Epub 2006 Aug 18.
Additional Infomation	Brevetoxin 3 has been reported in Karenia brevis with data available.

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	1.1147 mL	5.5735 mL	11.1470 mL
	5 mM	0.2229 mL	1.1147 mL	2.2294 mL
	10 mM	0.1115 mL	0.5574 mL	1.1147 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.