Fig. 2
![Fig. 2](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12872-018-0773-9/MediaObjects/12872_2018_773_Fig2_HTML.gif)
Upper panel: representative photomicrographs of left ventricle tissue with Masson staining (400× magnification). The AAC-model group showed the increased tissue interstitium and collagen protein expression (shown in blue color), while the LHRS and HHRS groups showed significantly less collagen protein expression. Low panel: quantitative calculation of collagen protein expression based on blue color volume