Table 3.
Effects of dopamine and PKA inhibitors and bafilomycin on sodium absorption under low and high perfusion rates in mouse proximal tubules
| 5 nl/min |
20 nl/min |
|||||
|---|---|---|---|---|---|---|
| Group | n | JNaa, pmol·min−1·mm−1 | n | JNab, pmol·min−1·mm−1 | ΔJNa (JNab − JNaa) | ΔJNa/JNaa * 100 |
| Control | 14 | 128.51 ± 3.99 | 15 | 198.31 ± 5.27b | 69.80 ± 6.64 | 54.31 ± 4.10 |
| Dopamine | 9 | 124.73 ± 11.66NS | 12 | 134.33 ± 9.39ns,e | 9.60 ± 14.74e | 7.69 ± 7.53e |
| DA + bafilomycin | 7 | 123.55 ± 6.63NS | 8 | 140.91 ± 6.57ns,e | 17.36 ± 9.33e | 14.05 ± 5.31e |
| DA + SCH | 11 | 141.64 ± 5.96NS | 13 | 254.29 ± 7.37b,e | 112.65 ± 9.56e | 79.53 ± 5.20e |
| DA + Sul | 10 | 122.31 ± 8.61NS | 12 | 163.75 ± 5.23b,e | 41.44 ± 9.86c | 33.88 ± 4.28d |
| DA + SCH + Sul | 7 | 163.97 ± 18.59c | 13 | 243.51 ± 20.01a,c | 79.53 ± 27.61NS | 48.50 ± 12.20NS |
| 8-Bromo-cAMP | 7 | 101.89 ± 5.04e | 10 | 149.74 ± 5.36b,e | 47.85 ± 7.40c | 46.96 ± 5.26NS |
| DA + H89 | 10 | 120.57 ± 13.18NS | 13 | 211.15 ± 8.21b,NS | 90.58 ± 15.07NS | 75.12 ± 6.81d |
| SCH2 | 6 | 115.88 ± 5.57NS | 8 | 199.7 ± 4.12b,NS | 83.83 ± 6.78NS | 72.34 ± 3.56d |
Values are means ± SE; n = number of perfused tubules. JNa, rate of sodium reabsorption; ΔJNa: the differences of JNa between low (JNaa) and high (JNab) perfusion rates (5 and 20 nl/min); ΔJNa/JNaa * 100, percent changes in sodium reabsorption from low flow rate. ns: not significant different from low flow rate in the same group; a,bsignificant difference from low flow rate in the same group (aP < 0.05; bP < 0.001). NS: not significant different compared with control at the similar flow rate; c,d,esignificant difference compared with control at the similar flow rate (cP < 0.05; dP < 0.01; eP < 0.001).