Apoptosis at wound sites. (a) TUNEL staining of wound sections were used for apoptosis detection (green), and DAPI staining was performed to visualize the total cell number (blue). Scale bars, 75μm for × 20 images. Cell counting was performed at × 20 magnification. Quantification of apoptosis ratio was achieved by plotting the number of TUNEL-positive cell against that of DAPI-positive cells (b). Wound cellularity was quantified by counting the number of DAPI-positive cells (c). Data are represented as means±s.e.m. (n=3 per genotype). *P<0.05 tested by one-way ANOVA with Bonferroni’s post hoc test, performed on Acta2+/+ vs Acta2−/−, respectively. ANOVA, analysis of variance; DAPI, 4',6-diamidino-2-phenylindole; TUNEL, terminal deoxynucleotidyltransferase (TdT) dUTP nick-end labeling.