title: Metabolism of acetylcholine in the nervous system of Aplysia californica. II. Reginal localization and characterization of choline uptake.
abstract: The choline required for synthesis of acetylcholine is derived exogenously by  Aplysia ganglia. Under physiological conditions choline was taken up primarlily by neuropile and nerves and not by cholinergic cell bodies. In addition, compared with their contents of choline acetyltransferase, those components of nervous tissue which contain nerve terminals and axons synthesized acetylcholine far more efficiently. Choline was accumulated by high and low affinity uptake processes; the high affinity process appeared to be characteristic of cholinergic nuerons (Swartz, J. H., M. L. Eisenstadt, and H. Cedar.1975. J. Gen. Physiol. 65:255).  The two uptake processes were similarly affected by  temperature with a  Q10 of 2.8. Both were dependent on a variety of ions in a complicated manner. High affinity uptake seemed to be more dependent on Na+, showed greater inhibition by ouabain, and was selectively inhibited by oxotremorine. We found that the functional state  of neurons did not alter uptake of radioactive choline by either process, nor did it change the conversion to radioactive acetylcholine.
mesh_terms: D000109:Acetylcholine / Q000378:metabolism*; D000123:Acetyltransferases / Q000378:metabolism; D000818:Animals; D001369:Axons / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002458:Cell Fractionation; D002794:Choline / Q000378:metabolism*; D003712:Dendrites / Q000378:metabolism; D004558:Electric Stimulation; D005724:Ganglia / Q000378:metabolism / Q000648:ultrastructure; D066298:In Vitro Techniques; D008274:Magnesium / Q000378:metabolism; D008974:Mollusca / Q000378:metabolism*; D009411:Nerve Endings / Q000378:metabolism; D009417:Nerve Tissue / Q000201:enzymology / Q000378:metabolism; D009420:Nervous System / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology; D010095:Oxotremorine / Q000494:pharmacology; D010275:Parasympathetic Nervous System / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism; D013696:Temperature
chemical_list: D013395:Sucrose; D010042:Ouabain; D010095:Oxotremorine; D012964:Sodium; D000123:Acetyltransferases; D008274:Magnesium; D002794:Choline; D000109:Acetylcholine; D011188:Potassium; D002118:Calcium