Figure 8.

Effect of carbon monoxide on Kv4.2+β currents. (A) Peak current amplitude obtained by depolarizing steps to +60 (○) and +80 (•) mV from a holding potential of −60 mV in a cell transfected with Kv4.2+β is plotted against time. During the marked periods, the cell was superfused with solutions equilibrated with 100% N₂ or 80% N₂/20% CO as indicated in the figure. In this cell, the inhibition observed with hypoxia amounted to 15%, whereas in the presence of CO it was 4.5%; i.e., CO reversed by ∼70% the effect of low pO₂. (B) Averaged values (mean ± SEM) of current inhibition by hypoxia (100% N₂, open bar) and CO (20% CO in N₂, crosshatched bar) obtained in paired data from 11 cells, and expressed as in Fig. 4. *P < 0.001.