title: Pralidoxime--the gold standard of acetylcholinesterase reactivators--reactivation in vitro efficacy.
abstract: OBJECTIVE
  In this work, we aim to summarize the universality of this compound, its reactivation potential when different cholinesterase inhibitors are used.
  
  
  BACKGROUND
  Pralidoxime is considered as a gold standard of acetylcholinesterase reactivators--antidotes used in case of nerve agent poisonings. It has been commercially available for many years. However, several studies deem this oxime an old-fashion antidote.
  
  
  METHODS
  Pralidoxime was synthesized at our department. The reactivating efficacy was tested on 10% (w/v) rat brain homogenate that had been incubated with appropriate inhibitor for 30 minutes to reach 96% inhibition of AChE. Then, pralidoxime was added for 10 minutes. Measurements were performed at 25 degrees C, pH 8, and 10(-3) and 10(-5) M concentrations of AChE reactivators. The activities of brain AChE were measured by a potentiostatic method.
  
  
  RESULTS
  No sufficient reactivation was achieved at the concentration of 10(-5) M, which is a concentration that can be reached after administration of therapeutic doses. At a higher dose (10(-3) M), pralidoxime reactivated AChE inhibited by paraoxon, chlorpyrifos, Russian VX, VX and sarin.
  
  
  CONCLUSIONS
  From the obtained results, it is clear that pralidoxime seems to be a poor reactivator of AChE inhibited by organophosphorous AChE inhibitors and thus cannot be labeled as a universal reactivator (Tab. 1, Fig. 3, Ref. 31).
authors.affiliation: Centre of Advanced Studies, Faculty of Military Health Sciences, University of Defence, Hradec Kralove, Czech Republic. kucakam@pmfhk.cz
authors.forename: K
authors.initials: K
authors.lastname: Kuca
authors.forename: M
authors.initials: M
authors.lastname: Hrabinova
authors.forename: O
authors.initials: O
authors.lastname: Soukup
authors.forename: G
authors.initials: G
authors.lastname: Tobin
authors.forename: J
authors.initials: J
authors.lastname: Karasova
authors.forename: M
authors.initials: M
authors.lastname: Pohanka
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism*; D000818:Animals; D000931:Antidotes / Q000494:pharmacology*; D001921:Brain / Q000378:metabolism*; D002801:Cholinesterase Reactivators / Q000494:pharmacology*; D066298:In Vitro Techniques; D011220:Pralidoxime Compounds / Q000494:pharmacology*; D051381:Rats
chemical_list: D000931:Antidotes; D002801:Cholinesterase Reactivators; D011220:Pralidoxime Compounds; D000110:Acetylcholinesterase; C028797:pralidoxime