Fig. 7

The regeneration of the injured adult X. tropicalis heart is nearly scar-free manner. a1 Longitudinal section of an adult heart from a sham control. Bar = 400 μm (scale bar for a1–k1). a2 High magnification of the rectangle with a dotted line from a1. Bar = 100 μm (scale bar for a2–k2). a3 High magnification of rectangle with the dotted line from a2. Bar = 20 μm (scale bar for a3–k3). Longitudinal sections from amputated heart at 0 daar (b1–b3), 1 daar (c1–c3), 2 daar (d1–d3), 4 daar (e1–e3), 8 daar (F1–f3), 16 daar (g1–g3), 30 daar (h1–h3; an amputated heart regenerated with a perfect morphology), 30 daar (i1–i3; an amputated heart regenerated with a nearly perfect morphology), 60 daar (j1–j3; an amputated heart regenerated with a perfect morphology) and 60 daar (k1–k3; an amputated heart regenerated with a nearly perfect morphology). Fibrosis-like structures were stained in blue. In the hearts that were regenerated with a nearly perfect morphology, fibrosis-like structures was only observed in adhesion tissue, but not in the regenerated myocardium between 30 and 60 daar. B border area. R regenerated area. Six frogs were inspected for 30 and 60 daar, while three frogs were inspected for other time points respectively