Neutralization of Saxitoxin by Anti-Saxitoxin Rabbit Serum

摘要

Saxitoxin is one of the most lethal non-protein toxins known (LD50 approx 11.6 micrograms/kg, i.p., mouse, personal observations). This toxin blocks the sodium channel of nerve and muscle membranes and thereby prevents action potential propagation necessary for nerve conduction and muscle contraction. Saxitoxin is produced by dinoflagellates of the genus Gonyaulax. This study examined the ability of anti-saxitoxin rabbit serum to neutralize saxitoxin binding to specific sites in rat brain membranes. The more potent of these sera, antiserum A, when combined with saxitoxin in vivo, as illustrated by the fact tha mice injected i.p. with antiserum A (1:4) survived a s.c. injection 1 hr later of 16.7 micrograms saxitoxin/kg (1 LD99). Finally, antiserum A prevented death when injected i.v. immediately after s.c. injection of 16.7 micrograms saxitoxin/kg, however, antiserum injected by the i.p. and i.m. routes caused no significant increase in survival. This study indicates that antiserum can neutralize saxitoxin both in vitro and in vivo.