Paraoxonase-1 Effect on Dichlorvos Toxicokinetics

Objective To investigate the effect of paraoxonase-1(PON1) on dichlorvos toxicokinetics,to prove that it is a promising scavenger on organophosphates intoxication.Methods Wistar rats were randomly divided to 4 groups:dichlorvos administration group(A group):dichlorvos dissolved in corn oil was injected by intraperitoneal in a dose of 10 mg/kg.Paraoxonase-1(PON1) pretreatment group(B group):PON1 was injected in the tail vein in a dose of 9 600 U/kg before 30 min of dichlorvos administration.Treatment group(C group):atropine 0.05 mg/kg and pyraloxime chloride(PAM-CI) 120 mg/kg were injected via tail vein within 2 min after dichlorvos administration.Co-treatment group(D group):PON1 was injected in the tail vein in a dose of 9 600 U/kg before 30 min of 10 mg/kg dichlorvos administration by intraperitoneal,atropine 0.05 mg/kg and pyraloxime chloride(PAM-CI) 120 mg/kg were injected via tail vein in 2 min after dichlorvos administration.Blood was collected,plasma dichlorvos concentration was detected by liquid chromatography-mass spectra(LC-MS) method.Dichlorvos concentration was detected,toxicokinetics parameters were calculated in a statistical moment model.Results AUC(0→∞) in group B was statistically different from that of group A and C(P 0.05),while it was not different from group D(P 0.05);there was no statistical difference between group A and group C(P 0.05).The statistical results of Cmax were the same as AUC(0→∞)(P 0.05).There were no difference of MRT among four groups(P 0.05).Conclusion PON1 could decrease the amount of dichlorvos that entered blood,lowed down the peak concentration,while atropine + PAM-CI did not affect metabolism of dichlorvos.