FIG. 2.

HDAC inhibitors diminish steroidogenesis through modulating SF-1 level. (A) Normal Y1 cells and stable clones (18 and 55) were treated for 24 h without (CTRL) or with 100 ng/ml TSA or 2 mM VPA. Levels of SF-1, SF-1-HA, CYP11A1, CYP21, and HSP70, as determined by immunoblotting analysis, are shown. The asterisk denotes nonspecific cross-reacting material (CRM). (B and C) The progesterone (B) and corticosterone (C) levels in the medium of panel A were determined by enzyme immunoassay or radioimmunoassay and normalized to the corresponding cell numbers. All values represent the results of at least three separate experiments, with error bars representing standard deviations. *, P < 0.05; **, P < 0.01; ***, P < 0.001 (compared to control cells in each Y1 clone). N.D., not detected.