Influence of pH of the medium on free fatty acid utilization by isolated mammalian cells

• Main Author: Arthur A. Spector
• Format: Article
• Language: English
• Published: Elsevier 1969-03-01
• Series: Journal of Lipid Research
• Subjects: uptake; oxidation; esterification; release; albumin; Ehrlich ascites tumor cells
• Online Access: http://www.sciencedirect.com/science/article/pii/S0022227520426707

Studies with Ehrlich ascites tumor cells showed that small decreases in the pH of the incubation medium from 7.4 increase the magnitude of incorporation of free fatty acid (FFA) into the cells from an albumin solution. A similar effect occurred when rabbit erythrocytes, rat heart slices, or rat liver slices were incubated with FFA-bovine albumin solutions and when tumor cells were incubated with FFA in media containing human albumin, β-lactoglobulin, or rat plasma. The effect was not seen when the medium contained no protein.When the pH of the albumin-containing medium was lowered from 7.4 to 6.6, oxidation of FFA to CO2 by the tumor cells increased, esterification of the FFA (mostly into phospholipids and triglycerides) increased, and less esterified radioactive fatty acid was depleted from the cells. Hence, more fatty acid accumulated in the cells in more acid media.These findings suggest that small changes in extracellular pH might regulate FFA utilization and lipid accumulation in mammalian tissues.