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PubMed · 5086398

Choline: high-affinity uptake by rat brain synaptosomes.

H I Yamamura·S H Snyder
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Abstract

Synaptosomes from rat brain accumulate choline by two kinetically distinct processes, a high-affinity uptake system [Michaelis constant (K(m)) = 1 x 10(-6)M], and a low-affinity system (K(m) = 9 x 10(-5)M). The high-affinity uptake system requires sodium, and is associated with considerable formation of acetylcholine. The low-affinity uptake system is less dependent on sodium, and does not appear to be associated with a marked degree of acetylcholine formation. The high-affinity choline uptake appears to represent selective choline accumulation by cholinergic neurons.

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AcetylcholineAnimalsBasal GangliaBetaineBrain ChemistryCholineCorpus StriatumIn Vitro TechniquesKineticsMaleNerve EndingsOuabainPhosphorusRatsSodiumSynaptic VesiclesSynaptosomesTritiumJournal Article

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BibTeXRIS

H I Yamamura, S H Snyder. 1972-11-10. Choline: high-affinity uptake by rat brain synaptosomes.. https://doi.org/10.1126/science.178.4061.626

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