Effect of diets with different magnesium content in ischemic stroke rats.

Rats fed with low (0.015%), normal (0.08%) or high (0.32%) magnesium (Mg) diet for 5-6 weeks were subjected to photothrombosis-induced infarction. As compared to normal diet, Mg deprivation increased by 45% infarct volume at 24 h after photothrombosis but did not modify the lesion at 4 h after photothrombosis. Mg supplementation did not protect from infarction whatever the time point examined. No differences in pre-ischemic systolic blood pressure and glycemia as well as in post-ischemic kaliemia, calcemia and plasma antioxidant activity were observed between groups. However, plasma total Mg level correlated with plasma antioxidant activity at 4 h after photothrombosis. These results demonstrate that brains from Mg deficient rats are more susceptible to permanent focal ischemia than rats fed with normal or high Mg diet.