Figure 3.

1,25D ₃ and testosterone-induced 17β-estradiol secretion was mediated by calcium accumulation. (A) Granulosa cells were divided into vehicle, testosterone, testosterone plus 1,25D₃, L-type calcium channel blocker NIF (10 μM) or intracellular calcium chelator BAPTA-AM (10 μM) pre-treatment groups (n = 4–5 in each group). The individual levels of 17β-estradiol were also assayed using a radioimmunoassay. (B) Testosterone-induced 17β-estradiol released by granulosa cells cultured with or without NIF or BAPTA-AM in the absence of 1,25D₃ was measured (n = 9 in each group). (C) After NIF or BAPTA-AM treatment for 24 h, cells were subjected to the MTT reduction assay to measure cell viability. MTT reduction data are expressed as the percentage of values relative to the control group. The measurements were performed in triplicate, and each cytotoxicity experiment was repeated four times. The values represent the means ± SEM. #, p < 0.05; ##, p < 0.005 for comparison of two drug groups; a, p < 0.001 for comparison of 0.1 μg/mL and 0.01 μg/mL testosterone; b, p < 0.05 for comparison of 1 μg/mL and 0.1 μg/mL testosterone. The values listed within column indicate the means.