Ion Channel Modulators

Crotamine is a Na⁺ channel modulator. Crotamine is a 42 amino acid toxin cross-linked by three disulfide bridges. Crotamine has analgesic activity. Crotamine also interacts with lipid membranes and shows myonecrotic activity. Crotamine can be isolated from Crotalus durissus terrificus venom.

ω-Hexatoxin-Hv1a (ω-ACTX-Hv1; ω-Atracotoxin-HV1) is an orally active insecticidal neurotoxin containing an inhibitor cystine knot motif and a selective calcium channel inhibitor. ω-Hexatoxin-Hv1a blocks L-type voltage-dependent Ca²⁺ channels and reduces intracellular calcium ion concentration, thereby decreasing apoptosis, necroptosis and oxidative stress, and promoting cell recovery and energy level elevation. ω-Hexatoxin-Hv1a causes larval paralysis and death by impairing neurotransmission in the central nervous system of insects. It shows high injectable toxicity against insects of multiple orders, but exhibits weak oral toxicity. ω-Hexatoxin-Hv1a is widely applicable to studies related to ischemia-reperfusion injury, atopic dermatitis, and ischemic injury of cardiomyocytes and neurons.

AmmTX3 is a peptide toxin identified from the venom of the scorpion Androctonus mauretanicus. AmmTX3 is a highly specific blocker of K_v4 channels, which selectively and almost completely blocks transient A-type K⁺ currents with a K_i of 131 nM. AmmTX3 induces epileptiform behaviors and causes death in mice receiving intracerebroventricular injection. AmmTX3 increases the excitability of dentate gyrus granule cells, reduces GABAergic inhibition, enhances and stabilizes the EPSP-spike component of long-term potentiation, and impairs reference memory. AmmTX3 can be used in research related to pain, epilepsy, and autism spectrum disorder.

ProTx-III is a selective and potent inhibitor of voltage-gated sodium channel Na_v1.7, with an IC₅₀ of 2.1 nM. ProTx-III is a spider venom peptide isolated from the venom of the Peruvian green velvet tarantella. ProTx-III has a typical inhibitor cystine knot motif (ICK). ProTx-III is able to reverse the pain response. ProTx-III can be used to study diseases such as chronic pain, epilepsy, and arrhythmia.

GrTx1 is a peptide toxin originally isolated from the venom of the spider Grammostola rosea. GrTx1 blocks sodium channel, with IC₅₀s of 0.63 μM, 0.23 μM, 0.77 μM, 1.29 μM, 0.63 μM and 0.37 μM for Nav1.1, Nav1.2, Nav1.3, Nav1.4, Nav1.6 and Nav1.7, repectively. GrTx1 can be used for neurological disease research.

Jingzhaotoxin-III is a potent and selective blocker of Nav1.5 channels, with an IC₅₀ of 348 nM, and shows no effect on other sodium channel isoforms. Jingzhaotoxin-III can selectively inhibit the activation of cardiac sodium channel but not neuronal subtypes, and hopefully represents an important ligand for discriminating cardiac VGSC subtype.

6-FAM-AEEAc-Stichodactyla helianthus Neurotoxin (ShK) (6-FAM-AEEAC-SHK) is a polypeptide that can be used as a Biochemical Assay Reagents.

Agelenin is a polypeptide composed of 35 amino acids. Agelenin could be isolated from the Agelenidae spider Agelena opulenta. Agelenin has structural similarity to insect-specific calcium channel inhibitor.

Kaliotoxin (1-37) is a toxin from the scorpion Artdroctonus mauretanicus mauretanicus. Kaliotoxin (1-37) is a potent calcium-dependent potassium channel blocker.

Kaliotoxin is a peptidyl inhibitor of neuronal BK-Type. Kaliotoxin can specific inhibit Kv channels and calcium-activated potassium channels. Kaliotoxin can be used for the research of the regulation of membrane potential and neuron excitability.

Scyllatoxin (Leiurotoxin I) is a peptide toxin, it can be isolated from the venom of the scorpion (Leiurus quinquestriatus hebraeus). Scyllatoxin is a blocker of small-conductance K_Ca (SK) channel. Scyllatoxin enhances both norepinephrine (NE) and epinephrine (Epi) release in vivo.

Dendrotoxin K is a Kv1.1 channel blocker. Dendrotoxin K determines glutamate release in CA3 neurons in a time-dependent manner through the control of the presynaptic spike waveform.

OSK-1 is a potent K_v channel blocker with IC₅₀s of of 0.6 nM, 5.4 nM, 0.014 nM for K_v1.1, K_v1.2 and K_v1.3, respectively. OSK1 is a moderate blocker of Ca²⁺-activated K_Ca3.1 channel with an IC₅₀ of 225 nM. OSK-1 belongs to α-KTx3 toxins and is used as a immunosuppressive agent.

Mambalgin-1 is a toxin isolated from black mamba venom. Mambalgin-1 is a disulfide-rich polypeptide consisting of 57 amino acids and belongs to the family of three-finger toxins. Mambalgin-1 can bind to and stabilize ASICs (acid-sensing ion channels) in a physiologically relevant closed-channel conformation.

Lei-Dab7 is a potent and selective SK2 (KCa2.2) channels blocker with a K_d of 3.8 nM. Lei-Dab7 shows low or no activity on KCa1, KCa3, Kv and Kir2.1 channels.

Phrixotoxin 3 is a potent blocker of voltage-gated sodium channels, with IC₅₀s of 0.6, 42, 72, 288, 610 nM for NaV1.2, NaV1.3, NaV1.4, NaV1.1 and NaV1.5, respectively. Phrixotoxin 3 modulates voltage-gated sodium channels with properties similar to those of typical gating-modifier toxins, both by causing a depolarizing shift in gating kinetics and by blocking the inward component of the sodium current.

BeKm-1 TFA is a potent and selective KV11.1 (hERG) channel blocker. BeKm-1 TFA is selective for KV11.1 over a panel of 14 other potassium channels. BeKm-1 TFA dose-dependently prolongs QTc interval in isolated rabbit heart.

CALP3 TFA, a Ca²⁺-like peptide, is a potent Ca²⁺ channel blocker that activates EF hand motifs of Ca²⁺-binding proteins. CALP3 TFA can functionally mimic increased [Ca²⁺]_i by modulating the activity of Calmodulin (CaM), Ca²⁺ channels and pumps. CALP3 TFA has the potential in controlling apoptosis in diseases such as AIDS or neuronal loss due to ischemia.

Phrixotoxin 3 TFA is a potent blocker of voltage-gated sodium channels, with IC₅₀s of 0.6, 42, 72, 288, 610 nM for NaV1.2, NaV1.3, NaV1.4, NaV1.1 and NaV1.5, respectively. Phrixotoxin 3 TFA modulates voltage-gated sodium channels with properties similar to those of typical gating-modifier toxins, both by causing a depolarizing shift in gating kinetics and by blocking the inward component of the sodium current.

Agitoxin-2 TFA is a K+ channel inhibitor, with IC₅₀ values of 201 pM and 144 pM for mK_V1.3 and mK_V1.1, respectively).