The PCR reactions contained a final concentra tion of 1 SYBR Green PCR Master Mix (Applied Biosystems, Warrington, UK), 10 mM specific primers, and 2.5 ng of cDNA. Each gene expression were calculated according to the threshold cycle (CT) value, normalized using the value of the sample
with the lowest level of each product, and the data
were corrected according to the level of GAPDH.