Acetylcarnitine as a contamination in the radiochemical assay of acetylcholine synthesis in salivary glands and urinary bladders

It was previously shown that in a radiochemical assay using anion exchange resin the capacity to synthesize acetylcholine in salivary glands was markedly overestimated unless suitable controls were introduced. By the use of paper electrophoresis of the incubation mixture it is shown that the labelled acetyl group is not only transferred from acetyl-Coenzyme A to choline but also to carnitine in both salivary glands and urinary bladders. The two enzymes responsible for these processes, choline acetyltransferase and carnitine acetyltransferase, are shown to behave differently following denervation of the glands and bladders. Further, the adequacy of the introduced controls is demonstrated.