Rapeseed oil and magnesium manipulations affect the seizure threshold to kainate in mice

We have previously shown that the drop in N-methyl-D-aspartate (NMDA)-induced seizure threshold caused by nutritional magnesium deprivation responded well to the w-3 polyunsaturated fatty acid (PUFA) alpha-linolenate (ALA) (5% rapeseed oil) diet when compared to w-6 PUFA diet. In the present work, kainate-induced seizures are shown to be also exacerbated by magnesium deprivation. ALA diet better attenuates this seizure exacerbation when compared to the non-ALA diet. The reversion of the drop in kainate seizure threshold induced in these conditions by magnesium administration was, however, better under the non-ALA diet in comparison with the ALA diet. Taken as a whole, present data indicate that kainate like NMDA brain injury is attenuated by ALA diet. On the other hand, the relative failure of ALA diet to potentiate reversion induced by magnesium might suggest that magnesium and ALA protections are not additive.