RESUMEN
The levels of the free amino acids of the mouse brain were studied after convulsions induced by Metrazol; a decrease of level of taurine and a significant increase of level of alanine, phenylalanine and isoleucine were found. The net uptake of L-histidine by the mouse brain in vivo was similar under normal conditions and after Metrazol-induced generalized convulsions; that of L-methionine was much higher after convulsions and there was no uptake of L-aspartic acid, either under physiological conditions or after convulsions. The net uptake of L-histidine by various regions of the rabbit brain in vivo after convulsions was significantly higher than control values in the cortical areas, while that of L-methionine was significantly higher in the subcortical ones; there was no uptake of L-aspartic acid by the rabbit brain in normal condition, whereas after convulsions a small entry seemed to occur in the subcortical areas. These results indicate that cerebral permeability processes of amino acids are somewhat altered during convulsive phenomena, as already described elsewhere for ions andproteins.