RESINIFERATOXIN

Description

Resiniferatoxin (57444-62-9) is an ultrapotent TRPV1 activator (Ki=43 pM).1 Resiniferatoxin is 100-10,000 fold more potent than capsaicin for most responses yet displays a spectrum of activity distinct from capsaicin.2 A potent sensory neuron excitotoxin.3 Induces a long lasting analgesia in a rodent model of burn pain.4 SEVERE IRRITANT – HANDLE WITH CARE

Chemical Properties

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Uses

Resiniferatoxin has been used as an agonist to transient receptor potential vanilloid 2 (TRPV2):

• for complex preparation for cryo-electron microscopy structural studies
• to test its effect towards immune responses to?P.?aeruginosa in sensory neurons associated with the cornea
• to study its effects in the denervation of the peripheral sensory nerves in psoriatic mice

Definition

ChEBI: Resiniferatoxin is a heteropentacyclic compound found in Euphorbia poissonii with molecular formula C37H40O9. It is an agonist of the transient receptor potential cation channel subfamily V member 1 (TrpV1). It has a role as a TRPV1 agonist, a plant metabolite, a neurotoxin and an analgesic. It is a diterpenoid, an ortho ester, a tertiary alpha-hydroxy ketone, a member of phenols, a monomethoxybenzene, an organic heteropentacyclic compound, a carboxylic ester and an enone.

Hazard

A poison.

Biological Activity

Ultrapotent analog of capsaicin that is an agonist at vanilloid receptors (K i = 43 pM). Like capsaicin, it acts as a selective modulator of primary afferent neurons. Also available as part of the Vanilloid TRPV1 Receptor Tocriset™ .

Biochem/physiol Actions

Resiniferatoxin (RTX) is an analog of capsaicin. It effectively ablates corneal sensory neurons by activating transient receptor potential vanilloid 1 (TRPV1) channels. RTX facilitates corneal bacterial clearance. It also elicits protective functionality towards cardiac function in a rat model with congestive heart failure (CHF).

References

1) Szolcsanyi et al. (1990), Resiniferatoxin: an ultrapotent selective modulator of capsaicin-sensitive primary afferent neurons; J. Pharmacol. Exp. Ther., 255 923 2) Szallasi and Blumberg (1998), Resiniferatoxin and its analogs provide novel insights into the pharmacology of the vanilloid (capsaicin) receptor; Life Sci. 47 1399 3) Winter et al. (1990) Cellular mechanism of action of resiniferatoxin: a potent sensory neuron excitotoxin; Brain Res. 520 131 4) Salas et al. (2017) Local Resiniferatoxin Induces Long-Lasting Analgesia in a Rat Model of Full Thickness Thermal Injury; Pain Med. 18 2453