Fatty Acid Analysis. Subcutaneous adipose tissue
(100 mg) was extracted (in duplicate) according to
the method of Folch et al. (1957), and the extracted
lipids were methylated according to the Morrison and
Smith (1964) procedure, modified as described by
Sturdivant et al. (1992). Subsequently, the fatty acid
methyl esters were analyzed with a Packard Chrompack
gas chromatograph (model 437a, Chrompack,
Claritan, NJ) equipped with a stainless steel column
(3 mm ´ 10 m) packed with Chromasorb W-Aw 80/
100. Injector and detector temperatures were 225°C
and 215°C, respectively. Oven temperature was
180°C. The flow rate of the carrier gas (nitrogen) was
22 mL/min. To each sample, a known amount of an
internal standard (methyl laurate) was added. A
standard of known composition was analyzed to verify
the identity of the fatty acids in the samples. Fatty
acid peaks determined by gas chromatography were
then used to calculate amounts of fatty acids according
to calculations described by Slover and Lanza (1979).