Table 2

Pharmacokinetic parameters of probenecid

ProbenecidCLtotalCpssfpChssfh
μmol/min/kg ml/min/kg μM μM
  1.14.11  ± 0.07243  ± 40.243  ± 0.005205  ± 120.204  ± 0.011
  2.23.48  ± 0.04633  ± 190.214  ± 0.008420  ± 400.185  ± 0.040
  3.34.69  ± 0.08704  ± 120.258  ± 0.005541  ± 230.230  ± 0.009
  4.44.86  ± 0.15905  ± 120.286  ± 0.005831  ± 1690.159  ± 0.035

Both methotrexate (0.164 μmol/min/kg) and probenecid were infused intravenously at the indicated infusion rates. The steady-state probenecid concentrations in plasma and liver were determined, and pharmacokinetic parameters (mean ± S.E. of four rats) were calculated.