Magnesium levels in plasma, erythrocyte, and platelet in hypertensive and normotensive patients with type II diabetes mellitus.

The authors, by means of a recently introduced method, evaluated the intraplatelet concentrations of magnesium in 45 normotensive patients with type II diabetes mellitus, in 45 hypertensive diabetics and in 15 healthy controls. They also evaluated plasma and erythrocyte concentrations of the cation through direct current plasma spectrometer. Both normotensive and hypertensive diabetics showed a reduction in plasma, erythrocyte, and platelet concentrations of magnesium compared to controls. On the contrary, no significant difference was found between hypertensive and normotensive diabetics with regard to plasma and erythrocyte magnesium, whereas intraplatelet assay of the ion pointed out significantly lower concentrations of magnesium in hypertensive compared to normotensive patients (56.4 +/- 9.0 vs 60.7 +/- 10.2 micrograms/10(8) cells--p < 0.05). The authors believe that intraplatelet assay of magnesium may be the most reliable method for the evaluation of the cation in hypertensive diabetics, probably because platelets share common features with smooth muscle cells, including the alpha-2-adrenoceptor cyclase system and a coupling mechanism concerning the calcium-dependent contraction.