The peptide toxin δ-hexatoxin-MrIX inhibits fast inactivation of Na V s in mouse cerebellar granule cells.

•δ-hexatoxin-MrIX is a peptide toxin isolated from the venom of spider Macrothele raveni.•δ-hexatoxin-MrIX inhibited the inactivation of voltage-gated sodium channels in cerebellar granule cell.•δ-hexatoxin-MrIX could be used as a pharmacological tool to investigate the role of voltage-gated sodium channels in granule cell maturation.