Modulation of acetylcholine release in human cortical slices: Possible implications for Alzheimer's disease

Superfused slices of human neocortex, prepared from surgically removed tissue (to gain access to subcortical tumors) and prelabelled with [H-3]choline, were stimulated electrically to evoke action potential-induced, exocytotic [H-3]acetylcholine release. For comparison, rat cortex slices mere also used. [H-3]ACh release decreased with the age of the patients and was modulated by muscarinic autoreceptors and by 5-hydroxytryptamine(1F), neurokinin(1), and kappa-opioid receptors located on cholinergic terminals. In addition, 5-hydroxytryptamine(2) and delta-opioid receptors located on interneurons were also involved in the modulation of [H-3]ACh release. The present findings might help to explain pathological conditions in Alzheimer's disease. (C) 1997 Elsevier Science Inc.