Macroscopic membrane
current was recorded 48–72 h after injection as described previously.8 (link) The tested compounds were applied at pH 5.5 at
various concentrations when the inward current reaches maximum. The
compounds were applied for 2 min, and residual membrane current was
compared with the membrane current before the application of compounds.
Membrane currents were analyzed with pCLAMP 10.0 software package
(Axon Instruments, Sunnyvale, CA).