Evidence for active transport of alkali metal cations by calf lens

摘要: Additional experimental support is presented for an active transport of sodium and potassium across the surface calf lens. Since energy required can be derived from anaerobic glycolysis, since ouabain a relatively specific inhibitor cationic transport, amount needed calculated in rather simple manner. The inhibitory effects 10 −6 M were measured with respect to amounts lenticular potassium, lactate produced. Because each equivalent labile phosphate hexose as source energy, ratio changes cations could evaluated. ratios found 3 4 when mannose or fructose used. With glucose, it appeared necessary correct direct inhibition by this sugar. Application correction increased 2·0 – 2·5 3·5 − 4·5. There was no evidence experiments 22 Na that altered rates passive diffusion diffusional exchange, leading conclusion net change equalled actively transported sodium.