Omega-conotoxins act at presynaptic membranes, they bind and block voltage-gated calcium channels. This toxin blocks Cav2.2/CACNA1B calcium channels (IC(50)=0.67-208 nM) (PubMed:7826361, PubMed:26344359, PubMed:34589389). It acts by neutralizing the outer electronegativity and sterically hindering the ion access path to the entrance of the channel selectivity filter (PubMed:34234349). In vivo, is lethal to fish (PubMed:26344359, PubMed:34589389). In vivo, injection into mammals induces adverse effects, such as tremor, diminution of spontaneous locomotor activity and bad coordinated locomotion (PubMed:26344359). Expressed by the venom duct. The presence of a 'disulfide through disulfide knot' structurally defines this protein as a knottin. The cysteine framework is VI/VII (C-C-CC-C-C). LD(50) is 0.10 mg/kg by intramuscular injection into goldfish. LD(50) is 0.21 (0.18-0.24) mg/kg by intramuscular injection into goldfish (after 4 hours). Is available under the names Prialt by Neurex. It blocks acute pain in patients who no longer obtain relief from opiate drugs. It is 100 to 1000 times more potent than morphine. By blocking calcium channels it disable nerves that transmit pain signals. Belongs to the conotoxin O1 superfamily. Web site on ziconotide