Figure 1.

[Na]_i and pH_i in X. laevis oocytes expressing various P-ATPase subunits. Oocytes were injected with various P-ATPase subunit cRNAs, as indicated below the bars. After a 2-day incubation of the oocytes in amphibian Ringer’s solution, [Na]_i was measured by using intracellular Na⁺-selective microelectrodes: results are expressed as mean ± SE; n = 6–25 oocytes, from 2–6 independent experiments. Under the same experimental conditions, pH_i was measured by using intracellular pH-selective microelectrodes: results are expressed as mean ± SE; n = 4–7 oocytes, from 2–3 independent experiments. Statistics were performed compared with control (β₁ or β_g expressing-oocytes) [Na]_i value or pH_i value. Statistical significance: NS, not significant; ∗∗∗, P < 0.001.