PLASMA AND MEMBRANE MG-PREGNANCY AND IN PREECLAMPSIA AS COMPARED TO HEALTHY FEMALE SUBJECTS - A PLASMALEMMAL MEMBRANE MODEL(+ CONCENTRATIONS IN NORMAL)

Decreased cellular Mg++ concentrations seem to be involved in the path ogenesis of preeclampsia. To investigate the changes in Mg++ metabolis m in normal pregnancy and preeclampsia plasma and membrane, Mg++ conce ntrations were determined in a clinical study as compared to healthy s ubjects. Subjects and methods: 25 healthy female subjects, 22 healthy pregnant, and 20 preeclamptic women were investigated. In each patient plasma and membrane Mg++ content were measured. In the preeclamptic g roup plasma Mg++ content was determined before and after an Mg++ suppl ementation, additionally. Plasma Mg++ concentrations were significantl y lowered in the healthy pregnant group (0.63 +/- 0.11 mmol/l) and the preeclamptic group (0.70 +/- 0.12 mmol/l) as compared to controls (0. 93 +/- 0.06 mmol/l) (p < 0.0001). After an Mg++ supplementation in the preeclamptic group, plasma Mg++ concentrations normalized (0.88 +/- 0 .18 mmol/l) (p < 0.0001). In erythrocyte membranes Mg++ content was fo und significantly decreased in the preeclamptic women (0.28 +/- 0.09 m mol/g membrane protein) as compared to healthy subjects (0.55 +/- 0.13 mmol/g membrane protein) (p < 0.001). In conclusion, lowered plasma a nd membrane Mg++ concentrations in preeclampsia may contribute to the development in hypertension in pregnancy.