GrTx1

GrTx1 toxin is a peptide originally isolated from the venom of the spider Grammostola rosea. GrTx1 preferentially blocks voltage-gated sodium channels. GrTx1 toxin is in the same cluster than other famous sodium channel blockers such as ProTx-II, GsAF-1 and GsAF-2. GrTx1 potently and selectively blocks tetrodotoxin-sensivite channels. IC50 values for Nav1.1, Nav1.2, Nav1.3, Nav1.4, Nav1.6 and Nav1.7 have respectively been described to be of 0.63 µM, 0.23 µM, 0.77 µM, 1.29 µM, 0.63 µM and 0.37 µM.