The expression of inducible and endothelial nitric oxide synthase mRNA (iNOS and eNOS) using real-time RT-PCR. GAPDH serves as internal contrast. PMA upregulated iNOS significantly and eNOS modestly. NAC treatment reduced the iNOS and eNOS expression. To avoid redundance, only the effects of NAC 100 and 400 mg/g on PMA 4 μg/g are shown. PMA 0 serves as control.