The pharmacokinetics of (14C)-edrophonium in normal wistar rats and homozygous Gunn rats with ligated renal pedicles.

1 The distribution kinetics of [(14)C]-edrophonium were studied in both normal Wistar and homozygous Gunn rats with ligated renal pedicles.2 After intravenous injection the plasma concentration-time curve of [(14)C]-edrophonium was adequately fitted by a triexponential function in both species of rat and interpreted in terms of a three compartment model.3 The influence of the route of administration (i.e., systemic venous versus hepatic portal) of [(14)C]-edrophonium on its concentration in plasma was studied in normal Wistar rats with ligated renal pedicles. There was a marked difference in the area under the plasma concentration-time curve depending on the route of administration.4 The parameters of the model were determined and compared.5 The value of the metabolism rate constant was approximately the same in both species of rat. This suggests that the rate of conjugation of [(14)C]-edrophonium is unaltered in the homozygous Gunn rat despite the genetic lesion in UDP-glucuronyltransferase.