Figure 1.
Effect of HDL and LDL on progesterone secretion in SR-BI KD cells. A, HGL5 cells were seeded at 1.5 × 105 cells/well in a 12-well format. Scrambled (SCR, lanes 1 and 2) or SR-BI-specific siRNA was added (5 nm, lanes 3 and 4; 10 nm, lanes 5 and 6) for 24, 48, and 72 h to KD SR-BI protein expression. Levels of SR-BI protein were measured by Western blot and normalized to the loading control β-actin. B, Scrambled or SR-BI KD cells were incubated with DMSO or Fo ± HDL (50 μg protein/ml), ± LDL (50 μg protein/ml), ± serum (10%), or serum, HDL, and LDL alone for an additional 24 h. The data represent the mean ± se of three independent experiments, with each experiment performed using duplicate wells. *, P < 0.01 between scrambled and SR-BI KD cells.