The Efflux of Choline from Nerve Cells: Mediation by Ionic Gradients and Functional Exchange of Choline from Glia to Neurons
The availability of the precursors choline and acetyl Coenzyme A has been considered as one of the essential components for regulation of acetylcholine metabolism (12). One of the main pathways for the supply of choline to neurons for cholinergic metabolism is its transport across the plasma membrane. Recently, however, it has been shown that: a) choline can be synthesized in nerve cells (neurons and glia) by stepwise methylation of ethanolamine, and acetylcholine may be synthesized via this methylation pathway (8); and b) choline may be released from nerve cells following a mechanism which can be stimulated by, and is dependent upon, ions in a manner which is the mirror image of its flow into the cell (13).
KeywordsGlial Cell Nerve Cell Incubation Medium Ionic Gradient Acetyl Coenzyme
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