Chronic magnesium administration enhances oxidative glucose metabolism in thiazide treated hypertensive patients.
In newly-diagnosed untreated (n = 24) and thiazide treated (n = 18) hypertensive patients erythrocyte ion content and plasma ion and metabolite levels were determined. Thiazide treated patients had lower arterial blood pressure, plasma ion levels, erythrocyte magnesium and potassium content but higher fasting plasma insulin (66 +/- 7 v 87 +/- 8 pmol/L P < .02), triglycerides (1.88 +/- 0.24 v 2.34 +/- 0.44 mmol/L P < .05), free fatty acids (0.68 +/- 0.11 v 0.81 +/- 0.18 mmol/L P < .05). Subsequently, in a double-blind fashion and in random order thiazide diuretic treated patients were assigned to two groups: the first (n = 9) taking magnesium (15.8 mmol/day) and the other (n = 9) a placebo. Each treatment period lasted 8 weeks. At the end of each treatment period, each patient underwent blood sampling for determination of erythrocyte ion content and plasma ion and metabolite levels and was submitted to an euglycemic hyperinsulinemic (1 mU/kg/min for 120 min) glucose clamp. In this latter test D-3-H glucose infusion and indirect calorimetry allowed determination of glucose turnover parameters and substrate oxidation respectively. Chronic magnesium administration (CMA) raised fasting plasma (0.79 +/- 0.03 v 0.83 +/- 0.02 mmol/L, P < .05) and erythrocyte (1.98 +/- 0.08 v 2.35 +/- 0.03 mmol/L, P < .01) magnesium content. Along with insulin infusion, CMA improved glucose uptake, glucose metabolic clearance rate, and oxidative glucose metabolism. In the multiple linear regression analysis of the pooled basal data (n = 42), erythrocyte magnesium content displayed an independent correlation with basal plasma insulin levels (t = -2.08, P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)
Paolisso
G
G
Department of Geriatric Medicine and Metabolic Diseases, 1st Medical School, University of Naples, Italy.
Di Maro
G
G
Cozzolino
D
D
Salvatore
T
T
D'Amore
A
A
Lama
D
D
Varricchio
M
M
D'Onofrio
F
F
D000368:Aged; D001581:Benzothiadiazines; D001794:Blood Pressure / Q000187:drug effects; D004232:Diuretics; D005260:Female; D005947:Glucose / Q000378:metabolism*; D006801:Humans; D006973:Hypertension / Q000188:drug therapy* / Q000378:metabolism; D008274:Magnesium / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction / Q000187:drug effects; D049993:Sodium Chloride Symporter Inhibitors / Q000627:therapeutic use*; D013997:Time Factors
D001581:Benzothiadiazines; D004232:Diuretics; D049993:Sodium Chloride Symporter Inhibitors; D008274:Magnesium; D005947:Glucose