*2*.*8*. *Measurement of Total AA Level*

Total AA (AA + DHA) levels in the plasma and cortex have been determined by spectrophotometric method using Vitamin C Assay kit (ROIK02, Shima Laboratories, Tokyo, Japan) which is based on 2,4-dinitrophenylhydrazine method [33]. Briefly, plasma was mixed with an equal volume of 10% metaphosphoric acid solution. Cortex tissue was mixed with 14 times volume of 5.4% metaphosphoric acid solution and homogenized. After centrifugation of the solutions at 10,000× *g* for 15 min at 4 °C, the supernatants were used to the assay.
