Figure 3.

Senktide-mediated repression of GnRH transcription is specific to activation of the neurokinin 3 receptor. A, GT1-7 cells without endogenous NK3R expression were transiently transfected with rat NK3R, rat NK1R or pcDNA3.1 control vector and a –5 Kb GnRH Luc reporter and treated for 10 hours with either 30 nM senktide (gray) or vehicle (white). B, GT1-7 cells were transiently transfected with rat NK3R and a –5 Kb GnRH luciferase reporter. Cells were pretreated for 30 minutes with 2 μM SB 222200, a NK3R-specific inhibitor, and then cotreated with vehicle (0.1% DMSO) or 0.4 nM senktide for 8 hours. Luciferase values were internally normalized using a cotransfected β-galactosidase reporter to control for transfection efficiency and normalized to an external control. Data are represented as mean fold luciferase/β-galactosidase ± SEM for n = 3 independent experiments. Statistical analysis was performed using ANOVA with least squares means Tukey HSD (α = .05). *Significantly different from vehicle control.