Action of Organophosphate Anticholinesterases on the Three Conformational States of Nicotinic Receptor

  • Mugen Chi
  • Manji Sun
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 363)


Organophosphate and other ligands were examined for binding on the membrane-bond nicotinic receptor at three conformational states. Soman (pinacolyl methylphosphonofluoridate), sarin (isopropyl methylphosphonofluoridate, tabun (ethyl N-dimethylphosphoramidocyanidate) and phencyclidine did not show any effect on the binding of [25I]α-cobrotoxin to the nicotinic receptor. However, VX, O-ethyl-S-(2-diisopropylaminoethyl) methylphosphonothiolate, at concentrations higher than 10 umol/L exhibited profound inhibition on the equilibrium binding rates in a concentration-dependent manner. Agonist nicotine and antagonist d-tubocurarine also showed significant inhibitions.


Nicotinic Receptor Conformational State Total Binding Electric Organ Binding Rate 
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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Mugen Chi
    • 1
  • Manji Sun
    • 1
  1. 1.Institute of Pharmacology and ToxicologyBeijingChina

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