Renal transport and renal metabolism of 2, 4, 5-trichlorophenoxyacetate by the chicken.
In vitro and in vivo renal tubular transport of 2,4,5-trichlorophenoxyacetate (2,4,5-T), a hormone-type herbicide, was studied in the chicken. Renal cortical slices incubated with 14C-labeled 2,4,5-T demonstrated a slice-to-medium ratio of the 14C-label of 26 after 2 hr of incubation. This accumulation was inhibited significantly by probenecid, phenol red, dinitrophenol and iodoacetamide. In vitro metabolism of 2,4,5-T was apparent in the renal slice studies; at least two metabolites were found by electrophoretic analysis. Even though chicken liver slices were able to accumulate 2,4,5-T, the accumulated herbicide was not metabolized. In addition, chicken kidney slices metabolized 2,4,5-T to a  much greater extent than did rat or rabbit kidney slices, which produced only negligible amounts of metabolites. When [14C]-2,4,5-T was infused into the renal portal system of the chicken, the 14C-label originally associated with 2,4,5-T was shown to be secreted by the renal tubule. Probenecid inhibited the transport of the 14C-label without affecting the simultaneous transport of tetra-ethylammonium, an organic cation transported by the renal proximal tubule. At the present infusion rate of 2,4,5-T (2.9 X 10(-10) mol/min), the excreted label was associated primarily with an  acidic metabolite(s). It can be concluded that the chicken transports 2,4,5-T by a probenecid sensitive mechanism; however, this transport appears to be associated with the metabolism of the herbicide.
D015085:2,4,5-Trichlorophenoxyacetic Acid / Q000378:metabolism*; D000818:Animals; D000963:Antimetabolites / Q000494:pharmacology; D001692:Biological Transport; D002645:Chickens; D004590:Electrophoresis, Paper; D005260:Female; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D008099:Liver / Q000378:metabolism
D000963:Antimetabolites; D015085:2,4,5-Trichlorophenoxyacetic Acid