 Magi-5 competes with the scorpion beta-toxin Css IV for binding to the sodium channelat neurotoxin receptor site 4.One other known property of Magi-5 is its binding to site 3 of the insect sodium channel, observed in lepidopteran larvae, which raises the possibility of homology between the molecular structures of the binding site 3 (in insects) and 4 (in mammals).Raventoxin-VI blocks neuromuscular transmission in a rat phrenic nerve preparation.