Operational calixarene-based fluorescent sensing systems for choline and acetylcholine and their application to enzymatic reactions

Necropsy brain tissue from normal (control) patients and patients with depression and dementia was examined for activities of various cholinergic components, and these related to the degree of senile plaque formation and extent of intellectual impairment. Choline acetyltransferase and acetylcholinesterase activities decreased significantly as the mean plaque count rose, and in depressed and demented subjects the reduction in choline acetyltransferase activity correlated with the extent of intellectual impairment as measured by a memory information test; muscarinic cholinergic receptor binding activity remained unchanged with increasing senile plaque formation but butyrylcholinesterase activity increased. The results suggest a close relation between changes in the cholinergic system and Alzheimer's dementia, but the precise role of the system in this disease remains to be elucidated.

Life's Journey If life is indeed a journey, then poetry must be the map that reveals all its topographic possibilitiesellipsis while science is the compass that keeps us from getting lost. -R. T. Bartus, Simple Words for Complex Lives, (c) 1998 In the nearly 20 years since the cholinergic hypothesis was initially formulated, significant progress has been achieved. Initial palliative treatments for Alzheimer's disease (AD) have proven beneficial and have gained FDA approval, the use of animal models for studying AD and other neurodegenerative diseases has achieved wider acceptance, and important insight into the potential causes and pathogenic variables associated with various neurodegenerative diseases continues to increase. This paper reviews the current status of the cholinergic hypothesis in the context of continuing efforts to improve upon existing treatments for AD and explores the role that animal models might continue to play. Using the benefit of hindsight, particular emphasis is placed on an analysis of the approaches, strategies, and assumptions regarding animal models that proved useful in developing the initial treatments and those that did not. Additionally, contemporary issues of AD are discussed within the context of the cholinergic hypothesis, with particular attention given to how they may impact the further refinement of animal models, and the development of even more effective treatments. Finally, arguments are presented that, despite the deserved enthusiasm and optimism for identifying means of halting the pathogenesis of AD, a clear need for more effective palliative treatments will continue, long after successful pathogenic treatments are available. This review, therefore, focuses on issues and experiences intended to: (a) facilitate further development and use of animal models for AD and other neurodegenerative diseases, and (b) accelerate the identification of newer, even more effective treatments. Copyright 2000 Academic Press.