Figure 6.

Immunofluorescence micrographs displaying the gap junctions between cardiac myocytes surviving within 2-week-old (A) and 4-week-old (B) transmural post-MI scars. The viable cardiac myocytes are outlined using an antibody against laminin (green color), whereas the locations of gap junctions are visualized with an anti-connexin 43 antibody (red color). In both micrographs, nuclei are counterstained with DAPI (blue color). (A) High-power view showing surviving cardiac myocytes beneath the endocardium (arrows). (B) High-power view demonstrating surviving cardiac myocytes in close proximity to a large venous vessel (V) beneath the epicardium (white dotted line). Note that in A and B, the connexin 43 is accumulated on the lateral sides of viable cardiac myocytes displaying the typical gap junction arrangement along the interfacing surfaces of adjacent myocytes (arrowheads). Scale bars are 50 µm. Abbreviations: MI, myocardial infarction; DAPI, 4′,6-diamidino-2-phenylindole.