Beta-amyloid levels predict cholinesterase activity in human cerebrospinal fluid.

There is increasing evidence suggesting that beta-amyloid (Abeta) has a direct influence on cholinergic activity. In particular, Abeta has been shown to induce the expression of acetylcholinesterase in the brains of CT-100-expressing transgenic mice and in cell culture experiments. These data indicate a link exists between Abeta production and acetylcholinesterase expression in the human CNS. To test this hypothesis, Abeta levels and cholinesterase activity were measured in 110 human CSF samples. Abeta levels were found to have a significant and positive correlation with cholinesterase activity. This correlation was particularly strong in individuals > 50 years of age. These data support the hypothesis that Abeta can effect cholinergic activity and that this effect may be enhanced in the elderly.