Synthesis of Lecithin in the Animal Organism.*

The generally accepted view that the hydrolysis products of the fats in their transport across the intestinal wall recombine with the formation of triglycerides has led to the question as to the mechanism whereby such water-insoluble products as the neutral fats are transported in the circulating fluid to the tissues. A det,ailed study of this question has recently led Bloor (1) to postulate the view that the formation of lecithin, a substance quite miscible with water, might facilitate the transport of fat within the body. The similarity between the conventional structural formula of a lecithin and a triglyceride favors the view that the former may be synthesized from the latter. Lecithin synthesis within the organism is not unknown. McCollum, Halpin, and Drescher (2) proved it to take place in the growth of chickens; while Drosdoff (3) found that the blood as it passes through the liver gains in organic and loses in inorganic phosphorus, indicating that a synthesis of the former had taken place at the expense of the latter. Furthermore, Meigs, Blatherwick, and Carey (4) demonstrated the reversibility of the reaction in their observations that all of the milk fat produced by the dairy cow can be accounted for by the differences in the lipoid phosphorus coming t.o and leaving the mammary gland. In studying the question further Bloor (1) found in dogs that an increase in the total fatty acid and lecithin content of the whole blood takes place after fat