All points histograms from cell attached patch recordings shown in figure 3. The x-axis represents the current amplitude (pA) in 50 fA bins, and the y-axis is the number of recorded data points in each bin (from 0 to 1,800). (A) A typical/characteristic recording as was observed in most patches. The control (pink) data show a single peak at approximately 2.6 pA, representing the predominant TASK 1/3 heterodimer channel found in rat glomus type-1 cells. Isoflurane 2.5% (purple) modestly increased the activity of this channel, whereas halothane 2.5% (red) markedly increased the activity. A mixture of 2.5% halothane and 2.5% isoflurane (green) resulted in reduced (not increased) channel activity compared with 2.5% halothane alone. (B) A more unusual recording where the control (pink) histogram shows two peaks, one probably representing a TASK-1 homodimeric channel (at approximately 1.2 pA) and the other a heterodimeric TASK 1/3 channel (at approximately 2.5 pA). Isoflurane 2.5% (purple) increased the activity of the heterodimer but had minimal effect on the TASK-1 channel. However, halothane 2.5% (red) markedly increased the activity of both channels. The concentration mix (green) of agents, 2.5% halothane and 2.5% isoflurane, resulted in reduced (not increased) channel activity compared with that of 2.5% halothane alone for both TASK-1 and TASK 1/3 channels.