Oral magnesium supplementation in patients with essential hypertension.

Abstract

To elucidate the effects of magnesium on high blood pressure, a 4-week study of oral magnesium supplementation (MgO 1 g/day) was conducted in 21 outpatients with uncomplicated essential hypertension. During the study, blood pressure and intraerythrocyte sodium concentration decreased significantly, and the erythrocyte ouabain-sensitive Na efflux rate constant (K^ and intraerythrocyte magnesium concentration both increased. Serum triglyceride and free fatty add concentrations were reduced. Furthermore, the elevation in K m significantly and positively correlated with both the increase in intraerythrocyte magnesium concentration and the decrease in mean blood pressure. There was a significant inverse correlation between the prestudy K m and the decrease in mean blood pressure. In addition, when patients were divided according to their overall decrease in mean blood pressure, the prestudy intraerythrocyte sodium concentration was significantly higher in patients with a mean blood pressure decrease of more than 7 mm Hg than that of patients whose mean blood pressure decrease was less than 7 mm Hg. These results suggest that oral magnesium supplementation may lower blood pressure through the activation of a cell membrane sodium pump and may reduce serum lipid concentration. It also suggests that the lower the prestudy K m or the higher the prestudy intraerythrocyte sodium concentration, the more effective the oral magnesium treatment is in lowering blood pressure. Therefore, we concluded that appropriate oral magnesium intake might be effective as a nonpharmacological treatment for essential hypertension. (Hypertension 1989;13:227-232) E pidemiological surveys, clinical investigations, and experimental studies have currently reported '-^ that magnesium may play an important role in the pathogenesis of hypertension and atherogenesis. A recently proposed hypothesis 37 suggests that an impairment of the cell membrane sodium transport system is responsible for the increased total peripheral resistance found in essential hypertension. Magnesium controls cell membrane sodium pump activity, which in turn plays a major role in sodium-potassium transport across cell membranes, thereby affecting vascular tone and reactivity and blood pressure by influencing a Na + -Ca 2+ exchange mechanism. '-8 Furthermore, the atherogenic plasma lipid profile has been improved by magnesium supplementation. -10Thus, this study was designed to evaluate the effects of oral magnesium supplementation on blood pressure and on serum lipid profiles in patients with essential hypertension and to elucidate the From the First Department of Internal Medicine, Kobe University School of Medicine, Kobe, Japan.Address for correspondence: Takaaki Motoyama, MD, First Department of Internal Medicine, Kobe University School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe 650, Japan.Received August 1, 1987; accepted October 14, 1988. role of magnesium in controlling the cell membrane sodium pump. Patients and MethodsTwenty-one male outpatients with uncomplicate...

The effect of magnesium supplementation on biochemical markers of bone metabolism or blood pressure in healthy young adult females

“…Erythrocyte Mg content, expressed as nga10 6 cells and as mmolal, but not mgag Hb, was signi®cantly increased by Mg supplementation for 28 d. This accumulation of Mg in erythrocytes is in agreement with other studies that found increases in erythrocyte Mg content with Mg supplementation (Motoyama et al, 1989;Golf et al, 1990;Borella et al, 1993). Increases in Mg in both lymphocytes and muscle biopsies have also been documented after Mg a Direct treatment effect (namely, Mg supplementation) was analysed for each biochemical index by two sample t-tests of within group differences after testing for carry-over effects.…”

“…However, intervention studies with Mg therapy in hypertensives and normotensives have led to con¯icting results. Several studies in hypertensives and normotensives have shown a blood pressure lowering effect of Mg supplements (in hypertensives, Dyckner & Wester, 1983;Saito et al, 1988;Motoyama et al, 1989;Geleijnse et al, 1994;Witteman et al, 1994;in normotensives, Itoh et al, 1997), while others have not (in hypertensives, Cohen et al, 1984;Cappuccio et al, 1985;Henderson et al, 1986;Zemel et al, 1990;Durlach et al, 1992;Haga, 1992;Kisters et al, 1993;Plum-Wirell et al, 1994;Sacks et al, 1995;in normotensives, Haga, 1992;Yamamote et al, 1995;Sacks et al, 1998). Therefore, the effect of oral Mg supplementation on blood pressure remains controversial and especially, in normotensives where data is limited.…”

Decreased Platelet Free Magnesium with Increased Free Calcium in Mild Essential Hypertension.

“…The activity of membrane bound Na+-K+ATPase also depends on magnesium (8) . As we have reported previously (18,19), decreased intracellular magnesium availability would decrease Na+-K+ATPase activity and raise intracellular sodium, which in turn may lead to a rise in intracellular calcium due to augmented Na-Ca exchange (26). Because a decrease in intracellular magnesium (12) as well as an increase in intracellular calcium (1) are known to augment the contractility of vascular smooth muscle, the decreased intracellular free magnesium concentration and its inverse relationship to increased intracellular free calcium shown in the present study may account for the pathophysiology of the blood pressure elevation in essential hypertensive patients.…”

“…Blood pressure and pulse rate were measured after the subjects rested in the supine position for 30 min, and peripheral venous blood was then drawn for analysis of serum concentrations of electrolytes (sodium, potassium, calcium and magnesium) and creatinine, which were performed by autoanalyzer, as well as intraerythrocyte magnesium concentration, and the intracellular free magnesium and calcium concentrations of platelets. Intraerythrocyte magnesium concentration was determined as described previously (18,19) with a Hitachi atomic absorption spectrophotometer (HITACHI 207, Tokyo, Japan).…”

Dietary calcium and magnesium supplements in spontaneously hypertensive rats and isolated arterial reactivity

“…Oral magnesium supplementation has also been reported to British Journal of Phamacology (1995Phamacology ( ) 115, 1455Phamacology ( -1462 -ME funct-on iSH lower blood pressure in patients with essential hypertension (Motoyama et al, 1989), and intravenous Mg2" infusion to dilate coronary arteries in man (Vigorito et al, 1991). Since the long-term effects of magnesium supplementation on blood pressure during increased calcium intake are unknown, the present investigation was undertaken; we also examined the associated effects on arterial function and electrolyte balance in SHR and their normotensive control strain Wistar-Kyoto (WKY) rats.…”