Fig. 5.
Uroguanylin inhibits Na+-independent pHi recovery and hydrogen flux (JH+) in MDCK C11 cells. MDCK-C11 cells were treated with control solution (135 mM Na), 0 Na solution, or 1 μM uroguanylin diluted in 0 Na solution. After intracellular acidification by means of the ammonium pulse technique in MDCK-C11 cells, the initial rates of pH recovery (pH U/min) were calculated from the curves by linear regression analysis (A). B: plotted rates of hydrogen extrusion, which were obtained from the product of dpHi/dt and intracellular buffer capacity βi of the average pHi of the experimental groups (pHi 6.5). UGN significantly inhibits Na+-independent pHi recovery and hydrogen extrusion in MDCK-C11. Number of experiments is indicated in the bars. *P < 0.05 vs. control, #P < 0.05 vs. 0 Na.