In vitro comparison of two most promising H-oximes (HI-6 and HLo-7) and currently commercially available reactivators pralidoxime and obidoxime in reactivation of cyclosarin-inhibited human cholinesterases

This study describes the evaluation of the in vitro ability of two acetylcholinesterase (EC 3.1.1.7) reactivators, HI-6 and HLo-7, very promising at present, to reactivate human brain cholinesterases inhibited by the nerve agent cyclosarin. The results obtained (percentage of reactivation and appropriate constants characterizing the whole reactivation process) were compared with two currently available reactivators on the market: pralidoxime and obidoxime. It is clear that both promising oximes surpassed the potency of standard reactivators, especially at human relevant concentrations (10(-4) M and lower). Because of the prohibition of such experiments on humans, data obtained in this study could be used as input data for prediction of in vivo action of these drugs in future.