Raven J A
J Gen Physiol. 1967 Jul;50(6):1607-25. doi: 10.1085/jgp.50.6.1607.
The concentrations of K, Na, and Cl in the cytoplasm and vacuole, the tracer fluxes of these ions into and out of the cenocyte, and the electrical potential difference between bathing solution and vacuole and cytoplasm, have been measured in Hydrodictyon africanum. If the ions were acted on solely by passive electrochemical forces, a net efflux of K and Cl and a net influx of Na would be expected. Tracer fluxes indicate a net influx of K and Cl and efflux of Na in the light; these net fluxes are consequently active, with an obligate link to metabolism. The effects of darkness and low temperature indicate that most of the tracer K and Cl influx and Na efflux are linked to metabolism, while the corresponding tracer fluxes in the direction of the free energy gradient are not. Ouabain specifically inhibits the metabolically linked portions of tracer K influx and Na efflux. Alterations in the external K concentration have similar effects on metabolically mediated K influx and Na efflux. It would appear that K influx and Na efflux are linked, at least in the light.
已经对非洲水网藻中细胞质和液泡内K、Na和Cl的浓度、这些离子进出中心细胞的示踪通量，以及外部溶液与液泡和细胞质之间的电势差进行了测量。如果离子仅受被动电化学力的作用，预计会出现K和Cl的净外流以及Na的净内流。示踪通量表明，在光照条件下K和Cl为净内流，Na为净外流；因此，这些净通量是主动的，与代谢有着必然联系。黑暗和低温的影响表明，大部分示踪K和Cl的内流以及Na的外流与代谢有关，而沿自由能梯度方向的相应示踪通量则不然。哇巴因特异性抑制示踪K内流和Na外流中与代谢相关的部分。外部K浓度的变化对代谢介导的K内流和Na外流有类似影响。至少在光照条件下，K的内流和Na的外流似乎是相关的。
