Willis J S, Golden M H
Department of Physiology and Biophysics, University of Illinois, Urbana 61801.
Eur J Clin Nutr. 1988 Aug;42(8):635-45.
Erythrocytes of normal and malnourished children, both marasmic and oedematous (kwashiorkor), were equilibrated in standard incubation medium and their ion transport via the Na/K pump and the pathways of passive permeation were measured as unidirectional fluxes of 86Rb (as a congener of K) and 22Na. Cells of children with kwashiorkor exhibited a 65 per cent higher ouabain-sensitive K(Rb) influx ('pump rate') than those of normal or marasmic children. When allowance was made for cytoplasmic Na concentration, the pump rate was slower in younger (12 months and under) normal children than in older children. Judged by the same criterion, cells of older marasmic children also had slower steady-state pump activity. The passive permeation of K through the residual 'leak' pathway (ie, ouabain-and-bumetanide-insensitive influx) and Na permeation (ouabain-and-bumetanide-insensitive Na efflux) were greater in malnourished children than in normal children by a factor of two or more. During treatment for malnutrition, both Na-pump activity and ouabain binding increased rapidly in marasmic children. Passive permeation did not return to normal levels in malnourished children during the period of hospitalization.
将正常儿童以及患消瘦型和水肿型（夸希奥科病）营养不良的儿童的红细胞，在标准培养介质中进行平衡处理，并通过钠钾泵和被动渗透途径测量其离子转运，测量指标为86Rb（作为钾的同类物）和22Na的单向通量。患夸希奥科病儿童的细胞对哇巴因敏感的钾（铷）内流（“泵速率”）比正常或消瘦型儿童的细胞高65%。当考虑到细胞质钠浓度时，年龄较小（12个月及以下）的正常儿童的泵速率比年龄较大的儿童慢。按照相同标准判断，年龄较大的消瘦型儿童的细胞的稳态泵活性也较低。营养不良儿童中，钾通过残余“渗漏”途径的被动渗透（即对哇巴因和布美他尼不敏感的内流）以及钠的渗透（对哇巴因和布美他尼不敏感的钠外流）比正常儿童高两倍或更多。在营养不良治疗期间，消瘦型儿童的钠泵活性和哇巴因结合均迅速增加。在住院期间，营养不良儿童的被动渗透未恢复到正常水平。
