Magnesium has been called "nature's physiological calcium channel blocker" - “...Magnesium sulfate is widely used to prevent eclamptic seizures in pregnant women with hypertension. Vasospasm in preeclampsia is thought to be a consequence of endothelial dysfunction. Magnesium has been found, both in vitro and in vivo, to increase production of the vasodilator prostacyclin. Magnesium may also protect against damage to the endothelium by reactive oxygen species. The action of magnesium sulfate in the treatment of eclampsia can be accounted for by the release of endothelial prostaglandin by magnesium, its protection against reactive oxygen species damage to the endothelium and by its possible inhibition of platelet aggregation. It may act as an anticonvulsant via neuronal calcium-channel blockade and antagonism of the glutamate N-methyl-D-aspartate (NMDA) receptor...”
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