STABILITY OF BRAIN CONTENT OF MAGNESIUM IN EXPERIMENTAL HYPOMAGNESEMIA

Magnesium is important in cerebral function. If there is a deficiency and neurological symptoms accrue, we hypothesised that Mg2+ deficiency causes neurological symptoms by decreasing the level of Mg2+ in cereb ral tissue. The content of magnesium was determined in 12 brain struct ures in magnesium-deficient rats. Experiments were carried out for 40 days in two groups of Wistar male rats made magnesium-deficient (MD) b y a well-controlled diet (50 mg of Mg2+/kg of food), and a control gro up (CG) rats fed normal diet (1 g of Mg2+/kg of food). At the end of t he 40 days, the clinical signs of hypomagnesemia were sought in the MD rats and Mg2+ concentration levels were measured in the blood and bra in. The results showed variable distribution of Mg2+ in the different brain structures, both in CG and MD rats; in the MD rats there is an i mportant stability of global Mg2+ content of the brain. Although the g lobal values for Mg2+ in the brain did not decline in MD rats, there w as a significant decrease in Mg2+ in the brainstem. We conclude that t he brain is able to maintain a stable concentration of Mg2+ during chr onic hypomagnesemia, but its topographic variations could account for some of neurological signs accompanying this condition. (C) 1997 Elsev ier Science B.V.