Department of Botany, University of British Columbia, V6T 1W5, Vancouver, B.C., Canada.
Planta. 1979 Jan;145(4):395-7. doi: 10.1007/BF00388368.
The electrochemical potential differences [Formula: see text] for potassium, between excised barley (Hordeum vulgare L.) roots and external media containing 0.05 mM KCl+0.5 mM CaSO4, were determined over a 4-h period during which initially low-K(+) roots accumulated K(+) by pretreatment in 50 mM KCl plus 0.5 mM CaCl2. This pretreatment resulted in increased internal [K(+)], decreased K(+) influx (as measured from 0.05 mM KCl+0.5 mM CaSO4) and decreased values of [Formula: see text]. These observations indicate that the decline of K(+) influx associated with increased internal K(+) concentration cannot be accounted for by passive adjustment to the electrochemical gradient for this ion.
在 4 小时期间，测定了离体大麦（Hordeum vulgare L.）根和含有 0.05 mM KCl+0.5 mM CaSO4 的外部介质之间钾的电化学势差 [Formula: see text]，在此期间，低钾（+）根通过在 50 mM KCl+0.5 mM CaCl2 中的预处理积累钾（+）。这种预处理导致内部 [K(+)]增加，K(+)流入减少（从 0.05 mM KCl+0.5 mM CaSO4 测量），并且 [Formula: see text] 值降低。这些观察结果表明，与内部 K(+)浓度增加相关的 K(+)流入的下降不能用这种离子的电化学梯度的被动调节来解释。
