LONG-LASTING EFFECTS OF AUDIOGENIC-SEIZURES ON SYNAPTOSOMAL NEUROTRANSMITTER AMINO-ACIDS IN RB MICE

Long lasting alterations of synaptosomal amino acid neurotransmitters following a single or several audiogenic seizures and/or acoustic stim ulations were investigated in six brain areas -olfactory bulbs (OB), a mygdala (A), hippocampus (Hi), cerebellum (C), inferior colliculus (IC ), ponsmedulla (P)- of three sublines of Rb mice: audiogenic seizure-p rone Rb1 and Rb2, seizure-resistant Rb3. Changes in the synaptosomal l evels of aspartate (Asp), glutamate (Glu), taurine (Tau), 4-amino buty rate (GABA), glycine (Gly) and some closely related precursors, serine (Ser) and glutamine (Gln), were recorded 15-18 hours after a single o r multiple acoustic stimulations. Changes were more frequent, or large r, after polystimulation. Some alterations appeared to be attributable to an effect of the acoustic stress. In both seizure-prone sublines, after a single or repeated seizures, an increase in synaptosomal Asp w as observed in IC. Decreases in Asp and Tau in OB and Ser in A, an inc rease in Gln in IC were only observed after repeated seizures, in Rb1 and Rb2 mice.