Figure 4.

Effect of at-RA on hemi-gap-junctional channels. (A) Hemi-gap-junctional current was induced by Ca²⁺-free solution at a membrane potential of 30 mV in an H2-type horizontal cell. The current was reduced from 797 pA to 257 pA by 1 μM at-RA. (B) Macroscopic patch-current induced by Ca²⁺-free solution in an outside-out membrane patch excised from an H2-type horizontal cell at the pipette voltage of 30 mV. The amplitude of this current was reduced by 1 μM at-RA. The current was filtered at 1 kHz and sampled at 3 kHz.