Ethanol predominantly alters sodium influx in human leucocytes.

1. Although ethanol appears to alter cellular sodium transport, the exact nature of its effects has not been clearly defined. We have studied the effects of different concentrations of ethanol on human leucocyte sodium content, and on the rise in leucocyte sodium content which occurs during sodium pump blockade with ouabain. 2. Sodium content was significantly reduced after a 20 min incubation with ethanol at concentrations between 17 and 170 mmol/l. 3. The rise in sodium content during a 20 min incubation with ouabain was significantly less in the presence of 170 mmol/l ethanol as compared with 17 mmol/l ethanol. 4. These results suggest that the effect of ethanol on intracellular sodium content is independent of sodium pump activity, i.e. it is mediated through reduced sodium influx.