Figure 10. Increasing temperature decreases oxygen concentration and decreasing oxygen content decreases neuronal excitability.

A. Oxygen levels (mm Hg), as measured at the upper surface of the slice, at different temperatures. Increasing temperature can dramatically decrease oxygen levels. B. Response of layer 2/3 pyramidal cells (n = 5) to the intracellular injection of a depolarizing current pulse (200 pA, 500 ms) at different temperatures (same experiments as in A). C. Plot of response of individual cells to the current pulse at different temperatures. D–F. Decreasing oxygen levels (mm Hg) at a constant temperature of 30°C does not have a significant effect on the duration of action potentials (D), but does decrease average firing rate (E), as seen in individual recordings (F; n = 8 cells).