Abstract
Synthesis of [3H]acetylcholine from [3H]acetyl-l-carnitine was demonstrated in vitro by coupling the enzyme systems choline acetyltransferase and carnitine acetyltransferase. Likewise, both [3H] and [14C] labeled acetylcholine were produced when [3H]acetyl-l-carnitine andd-[U-14C] glucose were incubated with synaptosomal membrane preparations from rat brain. Transfer of the acetyl moiety from acetyl-l-carnitine to acetylcholine was dependent on concentration of acetyl-l-carnitine and required the presence of coenzyme A, which is normally produced as an inhibitory product of choline acetyltransferase. These results provide further evidence for a role of mitochondrial carnitine acetyltransferase in facilitating transfer of acetyl groups across mitochondrial membranes, thus regulating the availability in the cytoplasm of acetyl-CoA, a substrate of choline acetyltransferase. They are also consistent with a possible utility of acetyl-l-carnitine in the treatment of age-related cholinergic deficits.
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White, H.L., Scates, P.W. Acetyl-l-carnitine as a precursor of acetylcholine. Neurochem Res 15, 597–601 (1990). https://doi.org/10.1007/BF00973749
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DOI: https://doi.org/10.1007/BF00973749
Key Words
- Choline acetyltransferase
- carnitine acetyltransferase
- acetylcholine synthesis
- synaptosomes