The Decrement of Muscarinic Receptor-Mediated Calcium Influx by Overexpression of APP in a Mouse Cholinergic Cell Line

Abstract

Kunishita, T., Ikeda, S., Araki, W. and Tabira, T. The Decrement of Muscarinic Recejptor-Mediated Calcium Influx by Overexpression of APP in a Mouse Cholinergic Cell Line. Tohoku J. Exp. Med., 1994, 174 (3), 225-239 The effects of β-amyloid precursor protein (APP) overexpressing on cell metabolisms of cholinergic neuronal hybridoma cell line (SN49) were examined. The cells stably overexpressing APP contained higher amount of GTP binding protein Go and cytosolic inactive protein kinase Cε, and showed less Ca2+influx through muscarinic acetylcholine receptor ml compared to original and mock cells which had been transfected with a vector alone. The contents of sn-1, 2-diacylglycerol and cycilc AMP were also reduced in the APP transfectants, although the similar changes were observed in the mock cells. These findings strongly suggest that the overexpression of APP affect the transient receptor-mediated ion channel and calcium-related cell metabolisms in neuronal cells. APP overexpression; cholinergic cell line; muscarinic receptor; protein kinase C; GTP binding protein. © 1994, Tohoku University Medical Press. All rights reserved.