Fig. 2

Effect of BI-9740 (BI) on myocardial morphology in grafts after heart transplantation (HTX). A Representative images of hematoxylin and eosin (HE) staining (× 200, scale bar: 200 µm) on cardiac tissue samples from the control group (41 pictures from 7 rats), HTX group (66 pictures from 11 rats) and HTX + BI group (44 pictures from 8 rats). In the HE staining images, nuclei are stained blue, cytoplasm is stained red, and collagen fibers display varying shades of red. B The degree of histopathological changes was assessed by examiners who were blinded to the experimental groups. The evaluation was conducted across 3–8 randomly selected, non-overlapping fields within each rat’s myocardial tissue. A indicates no changes; + , mild changes; +  + , moderate changes; and +  +  + , marked changes