Reduced Brain Somatostatin Levels in Alzheimer's Disease

To the Editor: Pharmacologic attempts to reverse symptoms of Alzheimer's dementia have thus far lacked conspicuous success. Most recent therapeutic strategies have been designed to correct a cholinergic loss arising from degeneration of acetylcholine-containing neuronal projections to the cerebral cortex. However, the widespread distribution of cholinergic depletion in Alzheimer's dementia¹ does not correlate with the focal distribution of functional brain abnormalities in this disorder, as determined by positron emission tomography with fluorodeoxyglucose (PET/FDG).² Thus, there is reason to suspect that stimulation of cholinergic transmission might not reverse a functionally relevant defect in the dementia. Imaging studies with PET/FDG suggest a.