Dietary changes in membrane lipids and leucocyte calcium.

It has been postulated that changes in the fatty acid component of cell membrane phospholipids play an important role in cell membrane ion handling. To test this hypothesis, we have administered the polyunsaturated fatty acid linoleic acid (as 4 g daily of safflower oil) to 25 normotensive volunteers in a double-blind crossover trial for 4 weeks. There was a significant decrease in leucocyte ionised calcium at the end of active treatment compared with the end of placebo period. There was no difference in subjects with and without a family history of hypertension and there was no significant effect upon blood pressure. It is concluded that cell membrane fatty acids play a role in the regulation of intracellular calcium in the leucocyte, and perhaps therefore in other tissues.