Study on toxicokinetics of paraquat by gavage in rabbits

  Objective  To study the toxicokinetics of paraquat by gavage in rabbits.

  Methods  Rabbits were administrated by gavage at the doses of 100 mg/kg and 200 mg/kg respectively. Blood samples were collected at different times after gavage. The content of paraquat in each sample was determined by liquid chromatography-mass spectrometry, the concentration time curve was drawn, and the toxicokinetic parameters were calculated by Das 3.0 software.

  Results  In low dose group (100 mg/kg), the T_max was (1.96 ± 2.41) h, then the paraquat concentration rapidly decreased. The main toxicokinetics parameters were: C_max(2.53 ± 0.84)mg/L; t_1/2z (8.41 ± 1.89)h; AUC (14.10 ± 3.21)mg/(L·h). In high dose group(200 mg/kg), the T_max was(1.76 ± 1.10)h and then the paraquat concentration rapidly decreased. The main toxicokinetics parameters were: C_max (9.21 ± 4.43)mg/L; t_1/2z (15.47 ± 12.11)h; AUC 76.05 ± 34.30)mg/(L·h). There was no significant difference in the peak time and average retention time of paraquat in plasma between these two groups(P > 0.05).

  Conclusions  The results show that the paraquat is consistent with three-compartment model for oral exposure. Toxicokinetics parameters of paraquat by oral exposure in rabbits were obtained.