Fibrosis mechanisms assessment in OSA and Sham rats. (A) ACE, (B) MMP-2 and (C) IL-6 mRNA expression (ng-equ) in the four cardiac chambers of Sham (n = 14) and OSA (n = 16) rats (Mean ± SEM, *P < 0.05). D. Plasmatic concentration (pg/mL) of IL-1β in Sham and OSA (Mean ± SEM, *P < 0.05). E. MMP-2 protein levels quantification. Representative MMP-2 blots (upper panel), Ponceau-stained membranes (middle panel) and normalized quantification (lower panel) (Mean ± SEM, *P < 0.05). n = 4-6/group. Left lane is a molecular-weight marker lane; the picture was obtained with visible light. Dashed line means non-contiguous lane. A.U.: Arbitrary Units.