Studies on the phosphorylcholine of rat liver

Abstract

Specific radioactivities of liver phosphorylcholine and lecithin were measured at various times after the injection of radioactive phosphate into the rat. Results indicate that phosphorylcholine is not formed in the liver by the breakdown of lecithin, nor does it appear to obey the Zilversmit el al. (1943) radioactive criteria for the sole immediate P precursor of liver lecithin. Chromatographic recovery of phosphorylcholine in the liver is increased after the injection of choline but not after starvation. Conversely, the recovery of liver glycerylphosphorylcholine is increased after starvation but is unaltered by choline administration. Chromatographic recoveries of both liver phosphorylcholine and glycerylphosphor; choline are markedly increased during insulin hypoglycemia.