Figure 9.

Proposed role of glial-expressed CLH-1 in intracellular and extracellular pH buffering. A, At neutral steady-state baseline pH, AMsh maintain intracellular buffering capacity via HCO₃⁻ leak (thin arrow) through CLH-1 down the HCO₃⁻ concentration gradient. B, Acidification of the extracellular space would shift the HCO₃⁻-buffering reaction to the right, resulting in depletion of extracellular HCO₃⁻. The excess protons in the extracellular space then activate CLH-1, which opens to allow the accumulated intracellular HCO₃⁻ to flow into the extracellular space down the reversed concentration gradient (thick arrow).