Sorbitol transport in rat renal inner medullary interstitial cells Jan B. Schüttert, G. Martin Fiedler, Clemens Grupp, Sabine Blaschke, R. Willi Grunewald  Kidney International  Volume 61, Issue 4, Pages 1407-1415 (April 2002) DOI: 10.1046/j.1523-1755.2002.00285.x Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 1 Time course of sorbitol uptake. The results represent the means from seven experiments ± SD. Cells were incubated in HEPES-Ringer buffer containing a sorbitol concentration of 10 mmol/L. Neither aldose reductase nor sorbitol dehydrogenase was used. Symbols are: (♦) 37°C; (▪) 4°C. (Inset) Difference between the 4°C and 37°C experiments. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 2 Concentration dependence. Sorbitol uptake in interstitial cells at different concentrations at with respect to sorbitol uptake at 80 mmol/L. Data are means ± SD. Cells were incubated at (♦) 37°C and (▪) 4°C in HEPES-Ringer buffer with aldose reductase inhibitor and sorbitol dehydrogenase inhibitor. (Inset) Difference between the 4°C and 37°C experiments after 15 minutes of incubation time. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 3 Trans-stimulation experiments. Cells were preincubated with 50 mmol/L sorbitol (trans-stimulation) or 50 mmol/L mannitol for five hours. The uptake was measured after the preincubation time. Cells were incubated in HEPES-Ringer buffer with 1 mmol/L sorbitol for 15 minutes. Data show the increase in %± SD of five duplicate experiments after trans-stimulation with sorbitol. There was a significant increase (P < 0.05). Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 4 (A) Effects of phlorizin, phloretin, and 4-(chloromercuri)benzoesulfonic acid (pCMBS) on sorbitol uptake. Cells were incubated in HEPES-Ringer buffer for 15 minutes at 37°C; phlorizin, phloretin, and pCMBS were added in the given concentrations. (B) Effects of cytochalasin A and B on sorbitol uptake. The means of three experiments ± SD are shown. Symbols are: (□) controls; () experimental conditions; *P < 0.05, **P < 0.01 vs. control. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 5 Uptake inhibition by cytochalasin B. Cells were incubated in 10 mmol/L sorbitol or 2-deoxy-D-glucose for 15 minutes. Cytochalasin B concentration was 0.01 mmol/L. The means of three experiments ± SD are shown; the difference of uptake inhibition was significant (P < 0.05). Symbols are: (□) controls; () experimental conditions. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 6 Inhibition of sorbitol uptake. Cells were incubated in HEPES-Ringer buffer for 10 minutes at 37°C. The extracellular sorbitol concentration was 1 mmol/L and the concentration of the sorbitol analogues was 5 mmol/L. The means of three experiments ± SD are shown; *P < 0.01 vs. control. Abbreviations are: Glu-6-P, glucose-6-phosphate; So-6-P, sorbitol-6-phosphate. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Figure 6 Inhibition of sorbitol uptake. Cells were incubated in HEPES-Ringer buffer for 10 minutes at 37°C. The extracellular sorbitol concentration was 1 mmol/L and the concentration of the sorbitol analogues was 5 mmol/L. The means of three experiments ± SD are shown; *P < 0.01 vs. control. Abbreviations are: Glu-6-P, glucose-6-phosphate; So-6-P, sorbitol-6-phosphate. Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Kidney International 2002 61, 1407-1415DOI: (10. 1046/j. 1523-1755 Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions

Kidney International 2002 61, 1407-1415DOI: (10. 1046/j. 1523-1755 Kidney International 2002 61, 1407-1415DOI: (10.1046/j.1523-1755.2002.00285.x) Copyright © 2002 International Society of Nephrology Terms and Conditions