Figure 3.

Expression and negative regulation of CCN3 in MCs by TGF-β. A: RT-PCR results for the indicated mRNA species run from the same set of three MC cultures in the presence or absence of TGF-β1 (2 ng/ml). Molecular weight markers are shown in the left lane. B: CCN3 protein secretion per cell in control and TGF-β-treated cultures after 96 hours. Shown are average ± SEM. *P < 0.05 versus control. Untreated MCs in culture gave low levels of CCN2 and COL1 mRNA and protein and high levels of CCN3 mRNA and protein. Exposure to TGF-β increased CCN2 and COL1 activity while simultaneously decreasing CCN3 activity. The experiment was repeated with similar results.