Interaction of the Neurotransmitter Acetylcholine with Aluminium, Calcium and Sodium

Binding of aluminium to acetylcholine has important biological implications particularly in Alzheimer's disease. An electrochemical technique, adsorptive cathodic stripping voltammetry, has been employed in this study to investigate the in-situ formation of a complex between aluminium and acetylcholine. The stability of the resulting complex was compared with that of the in-situ complexes formed between acetylcholine and sodium or calcium. From the shifts in the reduction potential of the metals on addition of acetylcholine it is concluded that a strong complex is formed between acetylcholine and aluminium. Much weaker complexes are formed between calcium or sodium and acetylcholine. These results have important implications in the aetiology of Alzheimer's disease-in which brain aluminium concentrations are known to be high and brain cholinergic function is lower than normal.