Relaxin Signals through a RXFP1-pERK-nNOS-NO-cGMP-Dependent Pathway to Up-Regulate Matrix Metalloproteinases: The Additional Involvement of iNOS
Figure 1
Relaxin positively regulates collagen-degrading associated MMPs in human and rat myofibroblasts.
(A) Representative gelatin zymographs of latent (L) and active (A) MMP-9, L-MMP-2 and L-MMP-1 from TGF-β1-treated ± H2 relaxin (10 ng/ml)-treated human dermal fibroblasts after 72 hours. (B) Representative zymographs of L-MMP-9, A-MMP-9, L-MMP-2, A-MMP-2 and Western blots of L-MMP-13 from rat renal myofibroblasts ± H2 relaxin (100 ng/ml)-treated rat renal myofibroblasts after 72 hours. Additional blots of α-tubulin (A,B) demonstrate the quality and equivalent loading of protein samples. Media from rat renal myofibroblasts was treated with APMA (5 mM) before being assessed by zymography. Also shown are the mean ± SE levels of each human (A) and rat (B) MMP studied (which was derived from the latent and active forms), as determined by densitometry scanning (from >10 separate experiments for each cell type studied), and expressed as relative values to those of the TGF-β1 alone-treated (A) or untreated (B) groups, which was expressed as 1 in each case. **p<0.01 vs TGF-β1 alone-treated cells (A) or untreated cells (B).