The lipids of whole blood. 2. The exchange of lipids between the cellular constituents and the lipoproteins of human blood.

In Part 1 (James, Lovelock & Webb, 1959) and in the earlier work of Altman, Watman & Solomon (1952), it was reported that the cellular constituents of the blood are able to incorporate activity from sodium [Me-14C]acetate into their lipid components. It was also shown that the radioactive lipids synthesized by the cells are transferred during the course of incubation in vitro to the plasma lipoproteins. From this earlier work little or no information is available on the contribution of the celLs to the lipid metabolism of the blood, or indeed to that of the whole animal. This paper reports experiments designed to determine quantitatively the turnover of the major lipid components, namely the phospholipids, the neutral fat and the unsaponifiable lipids, between the cells and the lipoproteins of the plasma.