Biosynthesis of the cerebroside odd-numbered fatty acids*

• Main Authors: Amiya K. Hajra, Norman S. Radin
• Format: Article
• Language: English
• Published: Elsevier 1962-07-01
• Series: Journal of Lipid Research
• Online Access: http://www.sciencedirect.com/science/article/pii/S0022227520404055

Rats were injected with radioactive acetate or propionate and, after four days, the saturated fatty acids were isolated from the brains and the brain cerebrosides. The amounts and specific activities of the individual normal and hydroxy acids were determined. In the rats given propionate, the odd-numbered acids (15:0 to 25:0) had much higher specific activities. In the rats given acetate, the differences were much smaller, with the even-numbered acids (16:0 to 26:0) showing higher specific activities. These data are consistent with earlier work, which indicated that the odd-numbered acids of other organs are derived from propionate and acetate. Comparison of the very long odd-numbered cerebroside acids with the more common ones (15:0 and 17:0) indicated that these are made by a similar synthetic route. Improved techniques are described for the isolation of the fatty acids. Comparison of the cerebroside acids and total brain fatty acids showed that most of the hydroxy acids are present in the cerebrosides. Hydroxystearic acid is a minor component of the hydroxy acid fraction; most of it is not in the cerebrosides. Degradation of the unsaturated acids from cerebrosides of rats given labeled propionate showed that propionate is a specific precursor of these acids also.