Phrixotoxin-3

Phrixotoxin-3 (PaurTx3 or Beta-theraphotoxin-Ps1a) is a valuable pharmacological tool to study voltage-gated sodium channels. Phrixotoxin-3, originally issued from the venom of the tarantula phrixotrichus auratus, has been shown to inhibit Nav1.1, Nav1.2, Nav1.3, Nav1.4 and Nav1.5 with respective IC50 values of 610 nM, 0.6 nM, 42 nM, 288 nM and 72 nM. It is thus considered as one of the most potent and almost selective modulator of Nav1.2.