Ng L L, Hockaday T D
Department of Clinical Pharmacology, Radcliffe Infirmary, Oxford.
Br J Nutr. 1989 Nov;62(3):639-45. doi: 10.1079/bjn19890064.
Cellular sodium transport via the Na+, K+-ATPase contributes significantly to daily energy expenditure. The effect of a meal on leucocyte Na+ transport and intracellular electrolytes was therefore investigated in lean normal subjects at room temperatures of 23 degrees and 33 degrees, to determine if the Na pump responds to the need for thermogenesis. In the fasting state, the ouabain-sensitive efflux rate which reflects active Na+ transport, and the intracellular electrolytes were similar. At 2 h after eating a 4.2 MJ (1000 kcal) meal, the ouabain-sensitive efflux rate constant rose when the room temperature was 23 degrees but not at 33 degrees. The ouabain-sensitive Na+ efflux rate, an index of active Na+ transport, rose post-prandially at 23 degrees only. The post-prandial activation of leucocyte active Na efflux in normal subjects was blunted at higher environmental temperatures, when the need for thermogenesis was reduced.
通过钠钾ATP酶进行的细胞钠转运对每日能量消耗有显著贡献。因此，在23摄氏度和33摄氏度的室温下，对瘦的正常受试者进食对白细胞钠转运和细胞内电解质的影响进行了研究，以确定钠泵是否对产热需求做出反应。在禁食状态下，反映主动钠转运的哇巴因敏感流出率和细胞内电解质相似。进食一顿4.2兆焦耳（1000千卡）的餐后2小时，当室温为23摄氏度时，哇巴因敏感流出率常数升高，但在33摄氏度时未升高。作为主动钠转运指标的哇巴因敏感钠流出率仅在23摄氏度时餐后升高。当产热需求降低时，正常受试者餐后白细胞主动钠流出的激活在较高环境温度下受到抑制。
