Figure 8.

Corneal endothelial plasma membrane transporters and channels. Locations have been previously discussed (9). This simplified scheme shows only elements relevant to transcellular ionic flows. Abbreviations: ch, channel; N3B, 3:1 HCO₃⁻-Na⁺ cotransporter; N2B, 2:1 HCO₃⁻-Na⁺ cotransporter; N, Na⁺; K, K⁺; B, HCO₃⁻; C, Cl⁻; H, H⁺. Electrogenic elements are in large lettering. The local (open circuit) recirculating current is also shown, with its direction marked by arrows. Na⁺ ions preferentially carry the current through the junctions.