Fig. 4.

Induction of LHβ gene expression by GnRH is mediated by the PKC signaling system. LβT4 cells were transiently transfected with 15 μg –1800LHβ-Luc reporter plasmid and 5 μg TK-CAT plasmid as an internal control. Sixteen hours after transfection, cells were treated with BMM I (100 nM) with or without GnRH agonist at 10 nM (A) or 1 nM (B), ionomycin (500 nM), or TPA (100 nM) for 6 h (A) or 24 h (B) before harvest. The value of the untreated sample for each time point was set to 100 to allow direct comparison of the magnitude of the GnRH induction. Results are the mean ± SEM of three independent experiments, each performed in duplicate. Asterisks (*) indicate a significant difference compared with the untreated cells. Groups marked with # are significantly different between the groups treated with the given reagent alone (GnRH, ionomycin, or TPA only) vs. treated with the combination of a reagent and BMM I.