title: Inhibition of human erythrocyte and plasma cholinesterases by methamidophos.
abstract: Methamidophos (O, S-dimethyl phosphoramidothioate) inhibition of human erythrocyte and plasma cholinesterase was studied in vitro. The pseudo-biomolecular rate constant of inhibition was 3.14 +/- 0.22 X 10(3) M-1 min-1 for erythrocyte cholinesterase and 1.85 +/- 0.01 X 10(3) M-1 min-1 for plasma cholinesterase. Thus methamidophos, although quite toxic to mammals, is a slow, rather non-selective inhibitor of human cholinesterases, as was also observed previously in rats.
mesh_terms: D000328:Adult; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007306:Insecticides / Q000633:toxicity*; D008297:Male; D009946:Organothiophosphorus Compounds / Q000633:toxicity*
chemical_list: D002800:Cholinesterase Inhibitors; D007306:Insecticides; D009946:Organothiophosphorus Compounds; C014655:methamidophos