FIGURE 9.

GRP170 overexpression reduces αENaC Na⁺ current in Xenopus oocytes. Oocytes were injected with αENaC cRNA (1 or 5 ng) and in the presence or absence of 5 ng GRP170 cRNA. Amiloride-sensitive currents were measured 48 h post-injection by two-electrode voltage clamp. Data represent the means of 21–25 oocytes from three frogs ±S.E.; *, p < 0.02. Amiloride-sensitive Na⁺ currents were normalized to the average amiloride-sensitive current of wild-type ENaC (1 ng) from the same batch of oocytes assayed on the same day. The average current in oocytes injected with wild-type ENaC (1 ng) varied between 30 and 100 nA.