BACKGROUND: The aim of our study was to compare the ability of two combinations of oximes (HI-6 + trimedoxime and HI-6 + K203) with atropine to counteract acute sarin-induced brain damage with the efficacy of antidotal treatment involving single oxime (HI-6) and atropin using in vivo methods. METHODS: Brain damage and neuroprotective effects of antidotal treatment were evaluated in rats poisoned with sarin at a sublethal dose (108 μg/kg i.m.; 90% LD50) using histopathological, Fluoro-Jade B and Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis 24 h after sarin administration. RESULTS: Both combinations of oximes reduce the number of rats that died before the end of experiment compared to non-treated sarin poisoning and sarin poisoning treated with HI-6 and atropine. In the case of treatment of sarin poisoning with HI-6 in combination with K203, all rats survived till the end of experiment. HI-6 with atropine was able to reduce sarin-induced brain damage, however, both combinations were slightly more effective. CONCLUSIONS: The oxime HI-6 in combination with K203 and atropine seems to be the most effective. Thus, both tested oxime combinations bring a small benefit in elimination of acute sarin-induced brain damage compared to single oxime antidotal therapy.

• Klíčová slova
• FluoraJadeB, HI-6, Histopathology, K203, Rats, Sarin, TUNEL, Trimedoxime,
• MeSH
• antidota terapeutické užití   MeSH
• kombinovaná farmakoterapie MeSH
• neurotoxické syndromy farmakoterapie   MeSH
• oximy terapeutické užití   MeSH
• potkani Wistar MeSH
• sarin otrava   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antidota MeSH
• oximy MeSH
• sarin MeSH

The ability of two newly developed oximes (K305, K307) to protect tabun-poisoned rats from tabun-induced inhibition of brain acetylcholinesterase, acute neurotoxic signs and symptoms and brain damage was compared with that of the oxime K203 and trimedoxime. The reactivating and neuroprotective effects of the oximes studied combined with atropine on rats poisoned with tabun at a sublethal dose were evaluated. The reactivating efficacy of a newly developed oxime K305 is lower compared to the reactivating efficacy of the oxime K203 and trimedoxime while the ability of the oxime K307 to reactivate tabun-inhibited acetylcholinesterase (AChE) in the brain roughly corresponds to the reactivating efficacy of the oxime K203 and it is slightly lower compared to trimedoxime. In addition, only one newly developed oxime (K307) combined with atropine was able to markedly decrease tabun-induced neurotoxicity although it did not eliminate all tabun-induced acute neurotoxic signs and symptoms. These results correspond to the histopathological evaluation of tabun-induced brain damage. Therefore, the newly developed oximes are not suitable for the replacement of commonly used oximes (especially trimedoxime) in the treatment of acute tabun poisonings.

• Klíčová slova
• acetylcholinesterase, functional observational battery, histopathology, neurotoxicity, oximes, rats, tabun,
• MeSH
• acetylcholinesterasa metabolismus   MeSH
• atropin terapeutické užití   MeSH
• chemické bojové látky otrava   MeSH
• lidé MeSH
• mozek účinky léků   enzymologie   MeSH
• neuroprotektivní látky terapeutické užití   MeSH
• neurotoxické syndromy farmakoterapie   MeSH
• organofosfáty toxicita   MeSH
• otrava organofosfáty farmakoterapie   MeSH
• oximy terapeutické užití   MeSH
• potkani Wistar MeSH
• pyridinové sloučeniny terapeutické užití   MeSH
• reaktivátory cholinesterasy terapeutické užití   MeSH
• trimedoxim terapeutické užití   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• acetylcholinesterasa MeSH
• atropin MeSH
• chemické bojové látky MeSH
• neuroprotektivní látky MeSH
• organofosfáty MeSH
• oximy MeSH
• pyridinové sloučeniny MeSH
• reaktivátory cholinesterasy MeSH
• tabun MeSH Prohlížeč
• trimedoxim MeSH

Acetylcholinesterase (AChE) reactivators were developed for the treatment of organophosphate intoxication. Standard care involves the use of anticonvulsants (e.g., diazepam), parasympatolytics (e.g., atropine) and oximes that restore AChE activity. However, oximes also bind to the active site of AChE, simultaneously acting as reversible inhibitors. The goal of the present study is to determine how oxime structure influences the inhibition of human recombinant AChE (hrAChE). Therefore, 24 structurally different oximes were tested and the results compared to the previous eel AChE (EeAChE) experiments. Structural factors that were tested included the number of pyridinium rings, the length and structural features of the linker, and the number and position of the oxime group on the pyridinium ring.

• MeSH
• acetylcholinesterasa chemie   MeSH
• cholinesterasové inhibitory chemie   MeSH
• katalytická doména MeSH
• lidé MeSH
• oximy chemie   MeSH
• simulace molekulového dockingu MeSH
• vazba proteinů MeSH
• vodíková vazba MeSH
• vztahy mezi strukturou a aktivitou MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Názvy látek
• acetylcholinesterasa MeSH
• cholinesterasové inhibitory MeSH
• oximy MeSH