Mice were weighed once a week, and food intake was recorded
3 times/wk. The diets were frozen in batches at 220C and defrosted and
replaced every other day to ensure minimal oxidation of the FAs. At the
end of the 10-wk intervention, food was removed for 16 h. The mice
were anesthetized by using 4% isoflurane in medical oxygen, and blood
was drawn by cardiac puncture into serum separation tubes (Becton
Dickinson). Glucose concentrations were measured in whole blood by
using an AlphaTRAK 2 glucose meter (Abbott Laboratories Ltd.).Blood samples were then allowed to clot for 30 min at room temperature before serum was separated by centrifugation (10 min, 1300 3 g at room temperature). Mice were transcardially perfused with an ice-cold saline solution containing sodium heparin (10 U/mL).Livers
were removed, rinsed with ice-cold 150 mmol NaCl/L, blotted, and
weighed. The right lobes were stored in RNALater (Sigma-Aldrich)
for gene expression analysis. The remainder of the liver, muscle
(gastrocnemius), and brain samples were snap-frozen, and all samples
were stored at 280C for further analysis. These tissues were chosen
due to their central role in EPA and DHA biosynthesis (liver), FA
utilization (muscle), and high n–3 PUFA, and in particular DHA,
content (brain).