The effect of acute ethanol administration on phosphorylethanolamine uptake and metabolism in rat liver slices.

Double-labelled phosphorylethanolamine with a [32P]//[14IA1 ratio of 1 was incubated in vitro with rat liver slices prepared from control and ethanol-intoxicated rats, and the radioactivity measured at given time intervals in liver ethanolamine, phosphorylethanolamine, phosphatidylethanolamine and phosphatidylcholine. Evidence is presented that after 10 and 15 minutes phosphorylethanolamine enters the slices as an intact molecule, which is directly converted into lipid forms by the Kennedy's pathways. At longer times a hydrolysis of the ester occurs which lowers considerably the theoretical [32P]/[14C]ratio. Fatty liver slices produced by acute ethanol intoxication uptake from the medium more phosphorylethanolamine than controls, and hydrolyze less efficiently than controls the phosphoric ester to ethanolamine and inorganic phosphate.

The effect of silybin on liver phospholipid synthesis in the rat in vivo.

Female Wistar rats have been injected intravenously for seven days with various different doses of silybin, the main component of the drug silymarin, and the in vitro synthesis of phosphatidylethanolamine and phosphatidylcholine from their respective precursors, CDP-ethanolamine and CDP-choline has been examined in liver microsomal membranes. Appreciable inhibition of the incorporation rates of precursors into lipids has been noticed at dosage of 15-20 mg/100 g body wt., daily. No evident effect is exerted by similar silybin treatment on choline and ethanolamine incorporation respectively into liver phosphatidylcholine and phosphatidylethanolamine in vivo.