Ion transport in the giant celled marine alga, Valonia ventricosa, was studied during internal perfusion and short-circuiting of the vacuole potential. The perfusing and bathing solutions were similar to natural Valonia sap and contained the following concentrations of major ions: Na 51, K 618, and Cl 652 mM. The average short-circuit current (I sc) was 97 pEq/cm2 sec (inward positive current), and the average open-circuit potential difference (PD) was 74 mv (vacuole positive to external solution). Perfused and short-circuited cells showed a small net influx of Na (2.0 pEq/cm2 sec) and large net influxes of K (80 pEq/cm2 sec) and Cl (50 pEq/cm2 sec). Unidirectional K influx was proportional to I sc, but more than one-half of the I sc remained unaccounted for. Both the I sc and PD were partly light-dependent, declining rapidly during the first 1–2 min of darkness. Ouabain (5 x 10-4 M) had little effect on the influx of Na or K and had no effect on I inf or PD. Fluid was absorbed at a rate of about 93 pliter/cm2 sec. Reversing the direction of fluid movement by adding mannitol to the outside solution had little effect on ion movements. The ionic and electrical properties of normal and perfused cells of Valonia are compared.
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机译：在内部灌流和液泡电位短路期间研究了巨大细胞海藻Valonia ventricosa中的离子运输。灌注和沐浴溶液类似于天然的Valonia汁液，并包含以下主要离子浓度：Na 51，K 618和Cl 652 mM。平均短路电流（I sc）为97 pEq / cm 2 sec（向内正电流），平均开路电势差（PD）为74 mv（对外部溶液为正真空） ）。灌注和短路的细胞显示出少量的Na净流入（2.0 pEq / cm 2 秒）和大量的K净流入（80 pEq / cm 2 秒）和Cl（50 pEq / cm 2 秒）。单向K流入与I sc成正比，但仍占I SC的一半以上。 Isc和PD都部分依赖于光，在黑暗的前1-2分钟内迅速下降。哇巴因（5 x 10 -4 M）对Na或K的流入几乎没有影响，对I inf或PD没有影响。流体以约93升/ cm 2 秒的速度被吸收。通过将甘露醇添加到外部溶液中来改变流体运动的方向对离子运动几乎没有影响。比较了Valonia正常细胞和灌注细胞的离子和电学性质。
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