RESUMO
[Summary] The activities of 17α-hydroxylase and 17,20 lyase of cytochrome P450c17 were evaluated by ELISA in NCI-H295R cells after treatment with palmitate and oleate. The results showed that 0. 75 mmol/L plamitate did not influence the activity of 17α-hydroxylase, but increased the activity of 17, 20 lyase by 74. 3% ( P<0. 05). Oleate at the same concentration did not change the activity of 17,20 lyase. There were no significant changes in the protein expressions of P450c17, P450 oxidoreductase, and cytochrome b5 after treatment with palmitate and oleate. However,reactive oxygen species in cells were elevated by palmitate. The results suggest that exposure to palmitate may increase androgen production by inducing 17, 20 lyase activity of P450c17 in NCI-H295R cells, which is related with oxidative stress-mediated post-translational regulation of the enzyme.