Incorporation of 32P-labelled intermediates into the phospholipids of cell-free preparations of rat brain

Abstract

In previous papers (McMurray, Strickland, Berry & Rossiter, 1957b; McMurray, Berry & Rossiter, 1957a) two systems capable of supporting the incorporation of inorganic 32p into the phospholipids of rat-brain dispersions were described: (a) an anaerobic system (best demonstrated in hypotonic dispersions), which supported the labelling of lipid P under optimum conditions for glycolysis (McMurray etal. 1957 b), and (b) an aerobic system (best shown in mitochondria isolated from isotonic dispersions), which supported the labelling of lipid P under optimum conditions for oxidative phosphorylation (McMurray et al. 1957 a). The effects of metabolia inhibitors such as 2:4-dinitro- phenol (DNP) and fluoride on the specific radio- activity and concentration of adenosine triphosphate (ATP) in each of these two systems suggested thlat the labelling of phospholipid was dependent upon both the prior labelling of ATP and the main- tenance of adequate concentrations of this sub- stance (McMurray et al. 1957 a).