2.9. Biochemical analyses
2.9.1. Lipid peroxidation by thiobarbituric acid reactive substances
(TBARS) assay
TBARS determinations were done in liver and serum according to
Ohkawa, Ohishi, and Yagi (1979), with adaptations. The organ samples
were macerated in liquid nitrogen. Samples (organs or serum) were
mixed with 8.1% sodium dodecyl sulfate (SDS) and working reagent
(2-thiobarbituric acid — TBA, 5% acetic acid and 20% sodium hydroxide).
After heating at 95 °C for 60 min, the samples remained in ice bath for
10 min and centrifuged at 10,000 g, 10 min. The supernatant was
read at 532 nm, using a clear 96-well microplate. Standard curve
(0.625–50 nmol MDA mL−1
) was obtained using malondialdehyde
standard (MDA). Results were expressed in nmol MDA mg−1 tissue
(or nmol MDA mL−1 serum).