Functional characterization of Na+-independent choline transport in primary cultures of neurons from mouse cerebral cortex.

Abstract

We report here the functional characteristics of Na+-independent choline transport system in primary cultures of neurons from mouse cerebral cortex. Na+-independent choline transport was saturable with a Michaelis constant (Kt) of 26.7+/-1.2 microM and a maximal velocity (Vmax) of 1.04+/-0.02 nmol/mg protein/10 min. Choline uptake was significantly influenced by extracellular pH and by membrane depolarization. This uptake system was inhibited by various organic cations including unlabeled choline, guanidine, diphenhydramine and the choline analog hemicholinium-3. However, the prototypical organic cation tetraethylammonium and cimetidine showed very little affinity for the Na+-independent choline uptake system in neurons. These results indicate that mouse cerebrocortical neurons express a Na+-independent, high-affinity choline transport system. RT-PCR revealed that choline transporter-like protein 1 (CTL1) and its spliced variant CTL1a, which have been reported to be novel Na+-independent choline transporter, are expressed in mouse cerebrocortical neurons. The Na+-independent transport properties of choline in mouse neurons is similar or identical to that of CTL1 and/or CTL1a. This choline transport system seems to have relevance not only for neuronal physiology but also for the uptake of pharmacologically important organic cation drugs.

Statistics

050100'06'07'08'09'10'11'12'13'14'15'16'17
Citations per Year

129 Citations

Semantic Scholar estimates that this publication has 129 citations based on the available data.

See our FAQ for additional information.

Cite this paper

@article{Fujita2006FunctionalCO, title={Functional characterization of Na+-independent choline transport in primary cultures of neurons from mouse cerebral cortex.}, author={Takuya Fujita and Ayumi Shimada and Naoki Okada and Akira Yamamoto}, journal={Neuroscience letters}, year={2006}, volume={393 2-3}, pages={216-21} }