Intracellular and membranous Mg2+ contents in essential hypertension

We have studied intracellular Mg2+ in lymphocytes and erythrocyte membranes from 18 untreated normotensives and 19 untreated essential hypertensive pa tients. As a reference for total Mg2+ content, we measured lymphocytic and membrane protein, according to Bradford's method. Mg2+ was measured by atom ic absorption spectroscopy. In patients with essential hypertension the tot al intralymphocytic Mg2+ content was significantly lower (0.07 +/- 0.05 mmo l/g lymphocytic protein, means +/- SD) than in controls (0.11 +/- 0.03 mmol /g lymphocytic protein, means +/- SD, P < 0.05). In erythrocyte membranes t he total Mg2+ content was significantly lower in essential hypertensives th an in the control group (0.28 +/- 0.03 versus 0.52 +/- 0.22 mmol/g membrane protein, means +/- SD, P < 0.01). Free intracellular Mg2+ content (measure d in lymphocytes by the fluorescent indicator mag-fura-II) showed no signif icant difference between normotensives and hypertensives (0.30 +/- 0.16 ver sus 0.38 +/- 0.17 mmol/l). There was no significant difference in plasma Mg 2+ concentration in the normotensive and hypertensive group (0.92 +/- 0.07 versus 0.88 +/- 0.07 mmol/l). Lowered total cellular and membrane Mg2+ conc entrations in a sub-group of essential hypertensives may be involved in the development of hypertension. Med Sci Res 27:591-593 (C) 1999 Lippincott Wi lliams & Wilkins.