Figure 3. Membrane potential during chemically induced hypoxia-reoxygenation in rat ventricular myocytes.

Representative whole cell (perforated patch) recordings from right ventricular myocytes at 5 mm [K⁺]_o in control conditions, during 8 min chemically induced hypoxia (CIH), and following 8 min reoxygenation. Traces from three cells (A, B and C) indicate the range of responses observed. Note the 5 to 10 mV depolarization that occurred in all cells. The ‘two stable membrane potential’ behaviour of these ventricular myocytes was seen in most cases and is characteristic of cells expressing a strong inwardly rectifying K⁺ current. Bursts of spontaneous action potentials were seen in 4 out of 8 recordings.