title: Acetylcholinesterase prophylaxis against organophosphate toxicity.
abstract: Fetal bovine serum acetylcholinesterase (FBS-AChE) protected mice from multiple LD50 doses of organophosphorus (OP) nerve agents. Mice were injected intraperitoneally (ip) with up to 3.3 mg (11,000 U) of FBS-AChE which exhibited a relatively long serum half-life and appeared well tolerated. The enzyme protected mice from the OP ethyl-S-2-diisopropylamino-ethylmethylphosphonothiolate (VX) with a stoichiometry equal to approximately 2 moles of enzyme active site per mole of VX. FBS-AChE, at a lower enzyme OP ratio, protected mice from 2 LD50s of the nerve agent methylphosphonofluoridic acid 1,2,2,-trimethylpropyl ester (soman) when used in conjunction with atropine and 2[(hydroxyimino)methyl]-1-methylpyridinium chloride. It is concluded that sequestration of highly toxic OPs by administration of AChE occurs in mice and suggests a new approach to treatment of OP intoxication.
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood / Q000627:therapeutic use*; D000818:Animals; D005260:Female; D007928:Lethal Dose 50; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009943:Organophosphorus Compounds / Q000037:antagonists & inhibitors / Q000633:toxicity*; D009946:Organothiophosphorus Compounds / Q000037:antagonists & inhibitors / Q000633:toxicity; D012999:Soman / Q000037:antagonists & inhibitors / Q000633:toxicity; D013045:Species Specificity
chemical_list: D000110:Acetylcholinesterase; D009943:Organophosphorus Compounds; D009946:Organothiophosphorus Compounds; D012999:Soman; C009680:VX-agent