Stearic acid, absorption phospholipid

The adsorption of ATP-14C to surface films of stearic acid and brain lipid was examined over an extended period of time under various conditions (Table I and Figure 6B). Table I shows the short-term results, where adsorption was studied during the first 30 minutes, and evaporation was not a factor. Upon adding stearic acid or brain lipid the measurable radioactivity decreased, probably as a result of displacement of ATP-14C from the surface layer and self-absorption of the beta particles by the lipid film. When PMCG was present, there was a slight but significant increase in the surface adsorption of ATP. The amount of ATP adsorbed was 4 X 10 10 moles/sq. cm. for stearic acid and 2.5 X 10"10 moles/sq. cm. for brain lipid. If the lipid concentration in the surface is assumed to be about 8 X 10 10M (as phospholipid in the case of brain lipid), the molar ratio of ATP to lipid would be about 0.5 for stearic acid and 0.3 for brain lipid. 

Bloch, R. (1974). Intestinal absorption of medimn-chain fatty acids. J. Nutr. Sci.,13,42-49. Bonanome, A., Bennet, M. Grundy, S. M. (1992). Metabolic effects of dietary stearic acid in mice changes in the fatty aeid composition of triglycerides and phospholipids in various tissues. Atherosclerosis., 94, 119-127. 

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