Alpha toxins bind voltage-independently at site-3 of sodium channels (Nav) and inhibit the inactivation of the activated channels, thereby blocking neuronal transmission (By similarity). Shows analgesic activity when intraperitoneally injected into mice. Expressed by the venom gland. Has the structural arrangement of an alpha-helix connected to antiparallel beta-sheets by disulfide bonds (CS-alpha/beta). Exists only in one form, with a trans isomerization at 28-Asp-Arg-29. The cis isomere does not exist (PubMed:19932686). Belongs to the long (4 C-C) scorpion toxin superfamily. Sodium channel inhibitor family. Alpha subfamily.