SUBCELLULAR LOCALIZATION OF N‐ACETYL‐ASPARTYL‐GLUTAMATE, N‐ACETYL‐GLUTAMATE AND GLUTATHIONE IN BRAIN

Abstract

Abstract— The subcellular distribution of N‐acetyl‐aspartate, N‐acetyl‐aspartyl‐glutamate, N‐acetyl‐glutamate and glutathione (reduced) was investigated. Lactate dehydrogenase, potassium, glutamate and aspartate were employed as markers of the cytoplasmatic compartments. Fumarate hydratase and choline acetyltransferase were used as mitochondrial and synaptosomal markers respectively. Our data show that the highest concentrations of NAA, NAGA, NAAGA and glutathione were localized in the supernatant with a smaller peak in the crude mitochondrial (P 2 ) fraction. On subfractionating P 2 , NAA was distributed similarly to aspartate and K + with a peak in the synaptosome (B) fraction, while glutathione and NAAGA were localized in the mitochondrial fraction. NAA, aspartate and K + were more readily released than glutathione and NAAGA from their particulate form on exposure to hypo‐osmotic conditions.