@article {Pritchard9, author = {J B Pritchard}, title = {Kinetic analysis of the renal handling of 2,2-bis(p-chlorophenyl) acetic acid by the rat.}, volume = {205}, number = {1}, pages = {9--18}, year = {1978}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {The kinetics of uptake and efflux of organic acids in rat renal cortical slices were used to examine the affinity of 2,2-bis(p-chlorophenyl)acetic acid (DDA) for the organic acid transport system and to assess intracellular binding of this polar 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) metabolite. As judged by its ability to inhibit p-aminohippuric acid transport, DDA was a potent competitive inhibitor, almost as strong as probenecid, the classical inhibitor of this system. Efflux of DDA from slices demonstrated that the bulk (85\%) of the DDA within the slice was reversibly bound to proteins or other macromolecules. Cortical slices incubated 60 minutes with 10 micron DDA contained a total concentration of 160 micron DDA within the tubular cells, but the actual free concentration in the cells was only 20 to 30 micron. Thus, although DDA was accumulated against a concentration gradient by the kidney, the gradient was much smaller than the measured tissue/medium ratio. Potential consequences of DDA exposure through its interaction with the organic acid system and roles of DDA binding sites in the toxicity and transport of DDA are discussed.}, issn = {0022-3565}, URL = {https://jpet.aspetjournals.org/content/205/1/9}, eprint = {https://jpet.aspetjournals.org/content/205/1/9.full.pdf}, journal = {Journal of Pharmacology and Experimental Therapeutics} }