Platelet intracellular pH and glucose metabolism in hypertensive patients

Intracellular platelet pH was studied by the BCECF fluorescent pH-sensitive intracellular indicator method in 52 patients with essential hypertension and 42 control subjects of similar age and sex. In 40 hypertensive patients studied by oral glucose tolerance test (standard OGTT) 23 presented with pathological blood glucose and plasma insulin values. Intracellular pH was on average higher in hypertensives (7.415 +/- 0.114, mean +/- SD) than in controls (7.348 +/- 0.109, P < 0.05), although there was a considerable overlap in values. In the group of hypertensive patients, no difference was observed between those with normal and those with pathological OGTT. There was also no significant correlation between intracellular pH and blood glucose, plasma insulin after OGTT, plasma cholesterol and triglycerides, age, BP or body mass index. These data are consistent with an anomaly of intraplatelet pH, perhaps owing to alteration of Na+/H+ exchange in essential hypertension, but do not indicate that this is related to a condition of hyper-insulinaemia or insulin resistance.