Figure 4
From: Calcitriol affects hCG gene transcription in cultured human syncytiotrophoblasts
Calcitriol stimulatory effects on hCG involve cAMP. A) Dose-dependent effects of calcitriol upon intracellular cAMP. Quantification of intracellular cAMP was determined by RIA after 10 minutes incubation in the presence of increasing concentrations of calcitriol or the vehicle (-). Effects of H-89 (a selective PKA inhibitor) upon calcitriol-dependent stimulation of hCG secretion and gene expression are shown in B and C, respectively. B and C) Cells were incubated with calcitriol (1 × 10-9 M) in the presence or absence of H-89 (5 μM) during 6 hours. In panel B, calcitriol incubations in the absence of H-89 represent 100% stimulation. In panel C results were normalized against GAPDH mRNA, giving vehicle data an arbitrarily value of 1. Each bar represents the mean ± S.D. of triplicate experiments. *P < 0.05 vs. control.