FIG. 4.

Electrophysiological recordings from retinal explant cultures. (A) Differential interference contrast and fluorescent images of the CCE-RX/E-derived cells in the retinal explant culture under the whole-cell voltage-clamped condition. Representative recordings of whole-cell currents from CCE-RX/E-derived cells (B), CCE-E-derived cells (E), and nonfluorescent host retinal cells (F) in the presence or absence of the ionotropic glutamate receptor antagonists CNQX (10 μM) and D-AP5 (25 μM). (C) Ten consecutive spontaneous responses recorded in CCE-RX/E-derived cells are superimposed (superimpose) and averaged (average). (D) A voltage step from −80 to −30 mV evoked an inward current (asterisk) in CCE-RX/E-derived cells, and the current was completely blocked by the sodium channel blocker TTX (1 μM). For the electrophysiological study, five CCE-RX/E derived cells, five CCE-E-derived cells, and six nonfluorescent cells were examined.