Impaired control of information transfer at an isolated synapse treated by aluminum: is it related to dementia?

Information transfer across an isolated cholinergic synapse exposed to aluminum was investigated using conventional electrophysiological techniques and computer-assisted analysis. Spontaneous and stimulation-induced release of neurotransmitter from frog motor nerve endings was augmented in the presence of aluminum (6–200 μg/ml). The release-enhancing effect of aluminum was dose-dependent and it was independent of the concentration of calcium ions in the extracellular solution. These results indicate that aluminum at concentrations similar to those found in the diseased brain of demented patients modulates synaptic transmission.