Table 4.
Effect of various inhibitors on the ATP-induced change in basolateral membrane potential
| +ATP (100 μmol l−1) | |||||
|---|---|---|---|---|---|
| Low Cl− condition | |||||
| Experimental series | n | Control Vm | Vm | Vm | (ΔVm) |
| No inhibitor | 14 | -67.5 ± 1.9 | -74.3 ± 2.1 | -57.3 ± 3.0 *** | (17.4 ± 1.7) |
| DPC (500 μmol l−1) | 11 | -59.1 ± 2.3 | -63.8 ± 3.5 | -48.4 ± 3.8 ** | (12.7 ± 2.1) |
| Niflumic acid (100 μmol l−1) | 4 | -62.5 ± 3.4 | -70.0 ± 3.8 | -46.5 ± 3.3 ** | (21.0 ± 4.1) |
| NPPB (100 μmol l−1) | 5 | -57.8 ± 2.5 | -61.8 ± 3.1 | -44.2 ± 3.4 *** | (17.2 ± 1.1) |
| Calix-4-arene (100 nmol l−1) | 4 | -63.7 ± 3.8 | -70.7 ± 3.4 | -42.5 ± 2.6 ** | (26.5 ± 4.1) |
| SITS (1 mmol l−1) | 7 | -70.7 ± 3.0 | -79.3 ± 3.4 | -79.0 ± 3.3 n.s. | (-0.3 ± 0.5) |
Basolateral membrane potential values (Vm, mV) of proximal tubular cells measured in a control condition (peritubular perfusate with normal Cl− concentration), in a low Cl− condition (peritubular perfusate in which sodium gluconate replaces NaCl) and in the low Cl− condition supplemented with 100 μmol l−1 ATP. The changes in Vm (ΔVm) induced by the presence of ATP to the low Cl− solution are indicated in parentheses. The experimental series indicates when an inhibitor was present in the perfusates.
**
P < 0.01
***
P < 0.001; n.s., not significant compared with the low Cl− condition.