Archives of Toxicology

, Volume 66, Issue 3, pp 216–219 | Cite as

Efficacy of HLö-7 and pyrimidoxime as antidotes of nerve agent poisoning in mice

  • John G. Clement
  • Arnold S. Hansen
  • Camille A. Boulet
Short Communication


The toxicity and efficacy of two oximes, HLö-7 and pyrimidoxime, were evaluated in mice and compared to those obtained with HI-6. HLö-7 and pyrimidoxime produced 24 h LD50 values of 356 and 291 mg/kg (i.p.), respectively. In combination with atropine (17.4 mg/kg, i.p.), HLö-7 was a very efficient therapy against poisoning by 3×LD50 dose of soman, sarin and GF and 2×LD50 dose of tabun with ED50 values of 12.4, 0.31, 0.32 and 25.2 mg/kg, respectively. In contrast, pyrimidoxime was a relatively poor therapy which resulted in ED50 values of >150, 5.88, 100 and 71 mg/kg against poisoning by soman, sarin, GF and tabun, respectively. HLö-7 produced significant (p <0.05) reactivation of phosphorylated acetylcholinesterase, in vivo, resulting in 47, 38, 27 and 10% reactivation of sarin, GF, soman and tabun inhibited mouse diaphragm acetylcholinesterase, respectively. HLö-7 also antagonized sarin-induced hypothermia in mice suggesting that it reactivated central acetylcholinesterase. The potential of HLö-7 as a replacement oxime for the treatment of nerve agent poisoning is discussed.

Key words

HI-6 HLö-7 Pyrimidoxime Reactivation Organophosphate Acetylcholinesterase Inhibition Toxicity Efficacy Therapy 


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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • John G. Clement
    • 1
  • Arnold S. Hansen
    • 2
  • Camille A. Boulet
    • 2
  1. 1.Biomedical DefenceDefence Research Establishment SuffieldRalstonCanada
  2. 2.Chemical/Biological Defence SectionsDefence Research Establishment SuffieldRalstonCanada

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