Introduction 1 l l 2+ 2 3 4 5 6 7 8 9 10 3 11 B 12 13 2+ 14 15 In the present study, we hypothesized that iNOS has a role in the regulation of renal ABC transporters during nephrotoxicity in vivo. An endotoxemia model was used in which rats were exposed to lipopolysaccharide (LPS), and the gene expression of 20 ABC transporters was evaluated. In addition, we examined the effect of the iNOS inhibitor, aminoguanidine, to determine whether the change in expression of the renal efflux transporters is caused directly by NO generated by iNOS. Materials and methods Animals and experimental design 16 + Escherichia coli + n − n 17 + + n + − Isolated kidney perfusion 18 Determination of mRNA expression 19 n Western blotting 20 21 2 22 Nitrate and nitrite determination 23 Histology and immunohistology 24 21 24 2 2 Isolated kidney perfusion + n − n 25 25 Statistical analysis P Results Signs of inflammation + t t 1 + t t + iNOS induction after LPS treatment − C T C T n C T n + 1 + + + 1 + − 1 1 Fig. 1 a + closed bars n gray bars n C T n C T − − double asterisks P triple asterisks P quadruple asterisks P n + b c  + 2 + 2 Fig. 2 − open bars n + closed bars n + gray bars n a b + − single asterisks P double asterisks P triple asterisks P + double sharp signs P triple sharp signs P  26 − + + 3 + 3 3 Fig. 3 a c green staining red + d e + f g G asterisks P D d f a c e g  Aminoguanidine restores the slightly impaired kidney function and loss of brush border membrane + 1 Table 1 Renal functional parameters Kidney function Time (h) − + + Total urine volume (ml) 3 1.6 ± 0.24 1.7 ± 0.27  6 2.4 ± 0.65 4.45 ± 0.98 7.3 ± 0.76 12 3.2 ± 0.57 a a 24 11.5 ± 0.25 13.7 ± 2.11  48 23.5 ± 3.47 18.0 ± 1.57  BUN (mmol/l) 3 6.6 ± 0.20 9.9 ± 0.74  6 4.6 ± 0.72 b b 12 6.3 ± 0.24 a b 24 7.0 ± 0.58 10.6 ± 0.58  48 6.5 ± 0.10 9.1 ± 0.38  Blood creatinine (mmol/l) 3 0.035 ± 0.002 b  6 0.039 ± 0.002 b d 12 0.037 ± 0.002 c e 24 0.038 ± 0.001 a  48 0.042 ± 0.001 0.052 ± 0.001  Glucose excretion (μmol/h) 3 0.290 ± 0.045 0.481 ± 0.341  6 0.333 ± 0.086 0.420 ± 0.100 0.478 ± 0.051 12 0.425 ± 0.106 0.537 ± 0.054 0.332 ± 0.080 24 0.254 ± 0.006 c  48 0.325 ± 0.037 0.606 ± 0.128  Creatinine clearance (ml/min) 3 1.33 ± 0.12 0.78 ± 0.19  6 1.06 ± 0.15 0.87 ± 0.09 0.93 ± 0.35 12 1.01 ± 0.05 0.90 ± 0.03 1.01 ± 0.13 24 1.19 ± 0.02 0.91 ± 0.20  48 1.00 ± 0.07 1.08 ± 0.37  Na 3 0.816 ± 0.004 0.365 ± 0.073  6 1.046 ± 0.145 b e 12 1.094 ± 0.097 a e 24 1.070 ± 0.024 c  48 1.033 ± 0.077 a  n + + n −  FE Na a b c d + e + + − 4 + 4 + 4 27 + 1 1 4 1 Fig. 4 + − a − b + c + + arrows a c d + closed bars n open bars n gray bars n − double asterisks P + sharp sign P  28 2 29 30 + 1 + B 13 31 + 1 + Abcb1a Abcb1b 32 2 C T + 5 + 5 2 + Table 2 Gene expression of efflux transporters during endotoxemia Gene symbol Protein synonym Assay IDs C T a − + t + t + t + t + t + t + t Abca1 Abca 1 Rn00710172_m1 7.1 ± 0.31 5.1 ± 0.16 5.8 ± 0.22 7.3 ± 0.55 7.3 ± 0.35 6.8 ± 0.23 6.1 ± 0.23 8.0 ± 0.12 Abca2 Abca 2 Rn00577821_m1 3.5 ± 0.40 3.5 ± 0.35 4.1 ± 0.15 4.5 ± 0.38 4.3 ± 0.35 3.6 ± 0.06 4.4 ± 0.38 4.4 ± 0.12 Abca5 Abca 5 Rn00597824_m1 9.8 ± 0.06 9.8 ± 0.35 9.8 ± 0.10 9.5 ± 0.12 10.0 ± 0.23 10.2 ± 0.21 9.5 ± 0.25 9.7 ± 0.35 Abcb1a P_gp Rn00591394_m1 8.4 ± 0.01 5       Abcb1b P_gp Rn00561753_m1 10.8 ± 0.04 5       Abcb4 Abcb 4 Rn00562185_m1 10.7 ± 0.62 12.3 ± 0.16 12.5 ± 0.21 12.8 ± 0.15 10.9 ± 0.15 7.3 ± 0.42 13.2 ± 0.46 12.4 ± 0.24 Abcb6 Abcb 6 Rn00589801_m1 5.5 ± 0.35 5.9 ± 0.26 6.4 ± 0.25 6.5 ± 0.52 5.9 ± 0.38 5.4 ± 0.14 6.4 ± 0.25 6.2 ± 0.32 Abcb9 Abcb 9 Rn00573757_m1 8.1 ± 0.20 8.5 ± 0.38 9.3 ± 0.29 8.8 ± 0.17 8.6 ± 0.10 8.7 ± 0.17 9.2 ± 0.42 8.9 ± 0.15 Abcb11 Bsep Rn00582179_m1 10.5 ± 0.40 8.6 ± 0.37 10.3 ± 0.24 11.9 ± 0.21 8.7 ± 0.17 5.4 ± 0.49 9.9 ± 0.21 9.7 ± 0.21 Abcc1 Mrp1 Rn00574093_m1 5.9 ± 0.25 6.2 ± 0.26 6.1 ± 0.25 6.1 ± 0.25 6.3 ± 0.21 5.9 ± 0.23 6.4 ± 0.40 6.2 ± 0.15 Abcc2 Mrp2 Rn00563231_m1 6.7 ± 0.31 5       Abcc3 Mrp3 Rn00589786_m1 8.4 ± 0.15 8.7 ± 0.12 8.8 ± 0.508 8.6 ± 0.06 8.0 ± 0.35 8.2 ± 0.12 8.8 ± 0.32 8.7 ± 0.23 Abcc4 Mrp4 Rn01465699_q1 6.6 ± 0.06 5       Abcc5 Mrp5 Rn00588341_m1 7.1 ± 0.01 7.9 ± 0.03 7.6 ± 0.15 6.4 ± 0.06 6.5 ± 0.50 6.5 ± 0.38 7.6 ± 0.45 6.4 ± 0.36 Abcc6 Mrp6 Rn00578778_m1 7.0 ± 0.14 7.0 ± 0.01 8.4 ± 0.21 8.4 ± 0.12 7.8 ± 0.05 6.8 ± 0.35 8.6 ± 0.07 8.3 ± 0.14 Abcc8 Sur1 Rn00564778_m1 11.5 ± 0.40 11.4 ± 0.21 11.4 ± 0.26 13.4 ± 0.15 14.8 ± 0.15 13.2 ± 0.25 11.7 ± 0.23 13.7 ± 0.31 Abcc9 Sur2 Rn00564842_m1 6.8 ± 0.01 7.7 ± 0.26 8.4 ± 0.31 8.1 ± 0.15 7.2 ± 0.32 6.8 ± 0.40 8.0 ± 0.35 8.2 ± 0.32 Abcg1 Abcg1 Rn00585262_m1 6.8 ± 0.15 7.8 ± 0.25 6.8 ± 0.25 7.1 ± 0.40 6.8 ± 0.31 6.7 ± 0.21 6.4 ± 0.31 7.3 ± 0.36 Abcg2 Abcg2 Rn00710585_m1 4.1 ± 0.24 4.5 ± 0.07 4.6 ± 0.21 5.0 ± 0.06 4.5 ± 0.14 4.5 ± 0.07 4.9 ± 0.42 5.2 ± 0.07 Abcg5 Abcg5 Rn00587092_m1 18.8 ± 0.29 b       a b C T Fig. 5 a b c d − open bars n + closed bars n + gray bars n C T − 2 − single asterisks  P double asterisks  P triple asterisks  P + sharp signs  P  5 + 6 + 2 Fig. 6 a b c d e f g n + a b + c + d e f g  + + 6 24 + 6 33 + 7 Fig. 7 a b arrows G asterisks P D a b  + 6 6 + − + 8 25 + 3 Fig. 8 closed squares n − open squares n + triangles n − asterisk  P  Table 3 − + Parameter n − n + n GFR (μl/min) 350 ± 25 380 ± 17 a Diuresis (μl/min) 18.6 ± 1.8 21.1 ± 1.3 17.4 ± 1.0 water 94.7 ± 0.2 94.5 ± 0.3 a b 88.4 ± 1.5 84.5 ± 1.7 88.7 ± 1.0 Materials and methods a b FR RPP Discussion + 34 35 20 24 36 + 37 24 36 38 40 41 42 39 34 35 43 44 45 46 44 47 48 24 49 + 50 51 + Electronic supplementary material Below is the link to the electronic supplementary material. 
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