Fig. 3. Electrophysiological responses of ENC1 to hypoxia in an explant culture recorded under whole-cell current clamp. (A) Under normoxic conditions, the membrane potential of ENC1 was around –70 mV. Hypoxia (approximately 90% reduction in oxygen concentration) elicited membrane depolarization and a burst of action potentials, followed by sustained membrane depolarization. Restoration of normoxia partially repolarized the membrane potential. A second cycle of hypoxia again elicited membrane depolarization and an action potential. (B,C) Action potentials elicited by the first and second cycle of hypoxia viewed on an expanded time scale.