title: Uptake of trimethoprim by renal cortex.
abstract: The purpose of this study was to examine the mechanisms involved in the uptake of the urinary antibacterial drug trimethoprim by incubated slices of rat renal cortex. Concentration-dependent studies of the uptake process demonstrated that a saturable component was involved. The results of inhibitor studies as well as the time-course pattern support the conclusion that at least two processes are involved in the uptake of trimethoprim. These include active transport via the organic cation system, accounting for about 40% of the total uptake, and a second component that continues to operate under conditions of inhibited cellular metabolism. Chromatographic examination of post-incubation bathing medium and slice extracts failed to demonstrate renal cortex metabolism of trimethoprim.
mesh_terms: D000818:Animals; D001693:Biological Transport, Active; D003080:Cold Temperature; D004140:Dinitrophenols / Q000494:pharmacology; D004734:Energy Metabolism; D005260:Female; D007672:Kidney Cortex / Q000378:metabolism*; D007700:Kinetics; D008297:Male; D009584:Nitrogen / Q000494:pharmacology; D011339:Probenecid / Q000494:pharmacology; D011803:Quinine / Q000494:pharmacology; D011806:Quinolinium Compounds / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D019789:Tetraethylammonium; D013757:Tetraethylammonium Compounds / Q000378:metabolism; D014295:Trimethoprim / Q000378:metabolism*; D014316:Tritium; D010130:p-Aminohippuric Acid / Q000378:metabolism
chemical_list: D004140:Dinitrophenols; D011806:Quinolinium Compounds; D013757:Tetraethylammonium Compounds; D014316:Tritium; C016855:cyanine 863; D019789:Tetraethylammonium; D011803:Quinine; D014295:Trimethoprim; D009584:Nitrogen; D011339:Probenecid; D010130:p-Aminohippuric Acid