Carmeliet E E, Lieberman M
Pflugers Arch. 1975 Jul 28;358(3):243-57. doi: 10.1007/BF00587221.
The effect of different concentrations of the antibiotic valinomycin, was determined on 42K efflux and Na, K content of embryonic chick hearts. Valinomycin produces an increase of K efflux which is progressive in time and markedly dependent on the concentration of external K (0-5 mM) and valinomycin (10(-8) to 10(-5) M). The changes in K efflux is not due to a reversal of the Na-K pump mechanism, secondary to ATP depletion: i) the increase of K efflux by valinomycin persists in the absence of external Na ions. ii) analysis of Na and K content and 42K influx measurements with and without valinomycin indicate that active K influx is not inhibited in a solution containing 0.5 mM K and only slightly decreased in a solution containing 5 mM K. Valinomycin, acting as a K carrier, presumably increases K conductance of the cell membrane resulting in a rise in K efflux.
测定了不同浓度的抗生素缬氨霉素对鸡胚心脏42K外流以及钠、钾含量的影响。缬氨霉素可使钾外流增加，这种增加随时间逐渐上升，并且明显依赖于细胞外钾（0 - 5 mM）和缬氨霉素（10(-8)至10(-5) M）的浓度。钾外流的变化并非由于ATP耗竭继发的钠钾泵机制逆转所致：i）在无细胞外钠离子的情况下，缬氨霉素引起的钾外流增加依然存在。ii）对有和没有缬氨霉素时钠、钾含量以及42K内流的测量分析表明，在含有0.5 mM钾的溶液中，主动钾内流未受抑制，而在含有5 mM钾的溶液中仅略有下降。缬氨霉素作为钾载体，可能增加了细胞膜的钾电导，从而导致钾外流增加。
