کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8993153 1556030 2005 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Carrier-Mediated Uptake of Grepafloxacin, a Fluoroquinolone Antibiotic, by the Isolated Rat Lung Cells
موضوعات مرتبط
علوم پزشکی و سلامت داروسازی، سم شناسی و علوم دارویی اکتشاف دارویی
پیش نمایش صفحه اول مقاله
Carrier-Mediated Uptake of Grepafloxacin, a Fluoroquinolone Antibiotic, by the Isolated Rat Lung Cells
چکیده انگلیسی
Grepafloxacin (GPFX) is a new quinolone antibiotic (NQ) which is highly distributed to the lung and other tissues. In the present study, to characterize the distribution mechanism of GPFX to the lung, the uptake of GPFX by isolated rat lung cells was examined in vitro. GPFX was rapidly taken up by the cells, and the uptake reached a steady-state within 5 min. The cell-to-medium concentration ratio at equilibrium was 56.8 ± 1.9 μL/mg protein, which was much higher than the cellular volume. GPFX uptake consisted of a saturable component (Km: 264 ± 181 μM, Vmax: 2.94 ± 2.33 nmol/min/mg protein) and a nonsaturable component (Pdif: 7.04±2.17 μL/min/mg protein). The uptake of GPFX was reduced in the presence of ATP-depletors (FCCP and Rotenone) and by the replacement of sodium with choline in the medium, suggesting that GPFX uptake is at least partially mediated by an Na+- and energy-dependent process. GPFX uptake tended to be reduced in the presence of other NQs such as levofloxacin, lomefloxacin and sparfloxacin, but was only minimally affected by the substrates of several uptake mechanisms already identified in the liver and kidney such as taurocholate, p-aminohippurate, L-carni- tine and tetraethylammonium. These results suggested that GPFX is taken up by the lung partially via carrier-mediated transport system(s), distinct from the identified transporters, and such active transport systems may at least partially account for the efficient distribution of GPFX to the lung.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Drug Metabolism and Pharmacokinetics - Volume 20, Issue 6, 2005, Pages 491-495
نویسندگان
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