Incorporation of ( 14 C)choline into phospholipids in the isolated phrenic nerve-diaphragm preparation of the rat

Abstract— The metabolism of ¹⁴C]choline has been studied in the isolated perfused phrenic nerve-diaphragm of the rat. We obtained no evidence that acetylcholine was synthesized from labelled choline in this system. There was extensive incorporation of the choline into phosphatidylcholine and its precursors, cytidinediphosphocholine (CDP-choline) and phosphocholine. Autoradiographic studies indicated that the lipids of myelin sheaths and nerve endings were the primary sites labelled.