Dealkylation and Loss of Capacity for Reactivation of Cholinesterase Inhibited by Sarin

Science  21 Oct 1966:
Vol. 154, Issue 3747, pp. 404-407
DOI: 10.1126/science.154.3747.404


Inhibition of rat brain acetylcholinesterase by 32P-sarin in vivo results initially in 32P-isopropylmethylphosphonylated enzyme. The percentage of inhibited enzyme that could not be reactivated by pyridinium aldoxime methochloride (aged enzyme) approximated the amount of radioactivity identified as 32P-methylphosphonate. The 32P-isopropyl methylphosphonate not released fromthe inhibited enzyme by the oxime accounted for 51 ± 10 percent ( standard deviation) of the radioactivity fixed to brain tissue. It showed no correlation with aging and was probably bound to sites other than acetylcholinesterase.