METABOLISM OF ARACHIDONIC ACID IN PHOSPHOLIPID

After albino rats were starved or fed with the fat and pyridoxine deficient diet, linoleic, linolenic and arachidonic acids and pyridoxine were administered. The amount of polyunsaturated fatty acids in phospholipid of the liver and muscle was then determined and the following results were obtained.1) Even if rats were fed on the fat deficient diet or starved, there were hardly any decreases of linolenic and arachidonic acids despite the decreases of linoleic acid in phospholipid.2) Under the existence of pyridoxine, linoleic, linolenic and arachidonic acids changed each other in phospholipid. In pyridoxine deficiency, linoleic acid failed to change into arachidonic acid, but arachidonic acid was changed in to linoleic acid.3) From the above mentioned results, it was suggested that arachidonic acid was metabolized into linoleic acid in phospholipid of white rats suggesting a possibility of a cycle formation between these two acids.