Short-term diabetes increases triacylglycerol arachidonic acid content in the rat liver.

Fatty acid compositions of liver phospholipid, cholesterol ester and triacylglycerol fractions obtained from streptozotocin-induced diabetic rats were compared to those from control or from simple-acidotic rats. Significant reductions of arachidonic acid proportions in phospholipid and cholesterol ester were found on the 3rd day after the streptozotocin treatment. In triacylglycerol, arachidonic acid and the other desaturation and elongation products of linoleic acid except for gamma-linolenic acid were increased in the diabetic rats.

Reduced levels of prostaglandin precursors in the blood of atopic patients: defective delta-6-desaturase function as a biochemical basis for atopy.

In the plasma phospholipids of a group of 50 young adults with atopic eczema, there was an elevation of cis-linoleic acid associated with a deficit of gamma-linolenic acid and of the prostaglandin precursors, dihomogammalinolenic acid and arachidonic acid. This suggests that atopics have a deficit in the function of the delta-6-desaturase enzyme which converts linoleic acid to gamma-linolenic acid. Carriers of cystic fibrosis tend to be phenotypically atopic, supporting previous suggestions that in homozygote cystic fibrosis patients the key defect may be in the delta-6-desaturase enzyme.