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1. A pulmonary tuberculosis mouse model was used to assess the pharmacodynamic and pharmacokinetic characteristics of tuberculosis therapeutics. While membrane transporters play important roles in drug disposition and physiological homeostasis, their expressional changes and contribution have never been analysed in a tuberculosis animal model. 2. The mRNA expression level of 20 Abc family transporters and 32 Slc family transporters in tuberculosisinfected mice were compared with those in naïve uninfected mice using real-time polymerase chain reaction (PCR). Mycobacterium tuberculosis infection induced many dramatic expression changes of families of both Abc transporters and Slc transporters at 4 and 8 weeks, as observed in the livers, kidneys, and intestines of test mice — and in a different mode, in the lungs and spleens as well. These changes were dependent on the tuberculosis progression with the tissue-specific manner, that is, in the lungs, the number of transporters of which the expression level changed due to M. tuberculosis infection had increased, and the magnitude of change also greater at 8 weeks, while in the spleen, the transcription of most transporters except Mrps had not changed or had recovered back to the same level of naïve transcription at 8 weeks. 3. Understanding the expression changes of transporters will assist in setting up rational preclinical dosing plans through the ability to predict the pharmacokinetics of new anti-tuberculosis chemotherapeutics and, furthermore, will assist in the design of safer and more efficient drug regimens. [ABSTRACT FROM AUTHOR]

1. The effects of folic acid-induced acute renal failure on the renal excretion of belotecan were investigated in rats after intravenous administration. 2. Both glomeruli and renal tubules were seriously damaged by folic acid-induced acute renal failure. The renal excretion clearance, CLr, of belotecan was significantly decreased by folic acid-induced acute renal failure. Furthermore, glomerular filtration rate and secretion clearance of the drug were dramatically decreased by folic acid-induced acute renal failure. 3. In vivo renal uptake of belotecan was inhibited by p-aminohippurate, whereas renal excretion was inhibited by GF120918, but not by verapamil and bromosulphalein. This indicates that Oat1/3 and Bcrp are involved in the renal uptake and urinary excretion of belotecan, respectively. 4. Both mRNA and protein levels of Oat1, Oat3 and Bcrp were significantly decreased in folic acid- induced acute renal failure rats. Based on the finding that belotecan is a substrate of OAT1 but not of OAT3, the decrease in CLr of belotecan in folic acid-induced acute renal failure could, therefore, mainly be attributed to the down-regulation of Oat1 and Bcrp, in addition to the decrease in glomerular filtration rate. [ABSTRACT FROM AUTHOR]