Exogenous aluminum accumulates in the lysosomes of cultured rat cortical neurons

In order to study the intracellular localization of aluminum, 0.01% AlCl 3 was added to rat cerebral organotypic cultures following 14 days incubation in a standard medium. The cultures were maintained in the aluminum (Al)-containing medium for 1 or 3 days. Subsequently, electron probe X-ray micro-analysis (EPXMA), was used to localize aluminum in the neurons. The Al was found in the cells as early as after 1 day of AlCl 3 exposure. The Al was detected exclusively in the neuronal lysosomes, in 66% (1 day exposure) and 97% (3 days) of the measured lysosomes. This localization was confirmed by laser microprobe mass analysis (LAMMA) measurements. Our results demonstrate an Al localization in the neurons, exposed to exogenous Al, different from that in the brains of patients with Alzheimer's disease.