Brain edema: induction in cortical slices by polyunsaturated fatty acids

The presence of polyunsaturated and saturated fatty acids in leukocytic membranes prompted study of their possible role in the induction of brain edema. Polyunsaturated fatty acids including sodium arachidonate, sodium linoleate, sodium linolenate, and docasahexaenoic acids induced edma in slices of rat brain cortex. This cellular edema was specific, since neither saturated fatty acids nor a fatty acid containing a single double bond had such effect.

An improved preparative method for D-erythrose 4-phosphate

The oxidation of 1 mmole of D-glucose 6-phosphate with 1.7 mmoles of lead tetraacetate admixed with 1.8 mmoles of sulfuric acid yields a preparation containing 0.77 mmole of D-erythrose 4-phosphate and 0.20 mmole of unoxidized glucose 6-phosphate. The D-erythrose 4-phosphate is separated from the D-glucose 6-phosphate by chromatography on Dowex 1-formate, and recovered as the barium salt of the hydrazone in 50% yield. Evidence is presented that erythrose 4-phosphate may exist in monomeric and dimeric forms. Glucose 6-phosphate and erythrose 4-phosphate produce different colors in the phenol – sulfuric acid reaction. This can be used for the qualitative identification and quantitative determination of these sugar phosphates.