STUDIES ON THE THERAPEUTIC EFFECT OF 2-PYRIDINE ALDOXIME METHIODIDE (2-PAM) IN MAMMALS FOLLOWING ORGANOPHOSPHORUS COMPOUND (OP)-POISONING (REPORT II) : AGING OF OP-INHIBITED MAMMALIAN CHOLINESTERASE

We studied the ability of 2-PAM to reactivate cholinesterase (ChE) inhibited by organophosphorus compounds (OPs) and aging. We estimated the reactivation rate with 2-PAM following inhibition of ChE by fenitrothion, methylparathion or ethylparathion using erythrocytes of rat and rabbit and rat brain. The period of time during which inhibited ChE could be reactivated was shorter in the case of inhibition by fenitrothion or methylparathion than in the case of inhibition by ethylparathion. This results suggest that aging is related to the presence of the alkyl group in OPs, and occurs faster in the case of inhibition by OPs with an O, O-dimethyl moiety than in the case of inhibition by OPs with an O, O-diethyl moiety.