Figure 8.

Saline conditions reduce FV currents in vacuoles from old quinoa leaves. Pipette and bath solutions contained 100 mm KCl. A and B, Whole vacuolar FV conductance was evaluated by taking the first derivative of the whole-vacuole I/V relation, measured immediately after achieving the whole-vacuole configuration. Vacuoles were isolated from either young or old quinoa leaves, grown in the presence of 50 mm NaCl (control) or saline (400 mm NaCl for 3 weeks; salt). Data are means ± se (n = 5–8 vacuoles). Solid lines are best fit to a three-state (open1-closed-open2) model (Pottosin and Martínez-Estévez, 2003). C, Same data as in A and B, but only the points within the physiological tonoplast potential range (±20 mV) are considered. O, Old leaves; Y, young leaves.