Vigilance states and cerebral monoamine metabolism in experimental magnesium deficiency

Correlations between cerebral monoamine metabolism and electrophysiological parameters were compared in 18 male Wistar rats subjected to a magnesium-restricted diet and in 14 normal rats. During the 40-day experimental period, plasma and erythrocyte Mg2+ levels and plasma Ca2+ and phosphorus levels were measured, and electroencephalographic tracings as well as clinical data were recorded at regular intervals. At the end of the study, the animals were killed and cerebral concentrations of monoamines and their metabolites were determined. Cerebral monoamine disorders characterized by a rise of dopamine and 5-hydroxyindole-3-acetic acid levels were observed in the magnesium-deficient group. This rise was accompanied by an increase in wakefulness and a decrease in sleep percent. The role played by magnesium in cerebral monoamine metabolism and sleep cycles is discussed.