Influence of PRCP on skin wound healing. (A) Full-thickness wounds from WT and PRCPgt/gt mice were imaged at D0, D2, D4, D6, and D8. Each unit on the ruler equals 1 mm in length. External wound images were obtained using a Nikon SMZ-U dissecting microscope (original magnification ×1). (B) Wound lengths are expressed relative to D0 length (n = 10 in both groups). On 2-way analysis of variance, the PRCPgt/gt wounds closed significantly slower (P < .047). (C) Hematoxylin and eosin–stained slides from D5 wounds of WT and PRCPgt/gt (gt/gt) mice that were untreated or treated with ramipril (T) were analyzed for their extent of reepithelialization. The red line demarcates the total length of the original wound; the white line represents the “wound gap.” The white arrows indicate the end of the epithelial tongues of a closing wound. In photographs in which no white line is seen, the wound gap is 0 and the wound has completely reepithelialized. (D) The percent reepithelialization is shown for WT (n = 21), gt/gt (n = 6), WT-T (n = 16), and gt/gt-T (n = 13) mice. (E) Frozen sections of D2 wounds were stained with anti–Gr-1 to assess neutrophil infiltration. (F) Mean number of neutrophils as pixels/HPF, 20× on microscopy (n = 6 in both groups). (G) Frozen sections from D5 skin wounds were stained for F4/80 to assess macrophage infiltration. (H) Mean number of macrophages as pixels/HPF on microscopy (n > 8 in both groups). (I) CD31 staining on frozen sections from D5 wounds in WT, gt/gt, WT-T, and gt/gt-T were obtained. (J) The area of CD31 staining in the 4 groups of animals was compared by morphometric analysis using the National Institutes of Health’s ImageJ software (n ≥ 5 in all groups). Fluorescent wound images were obtained using a Nikon TE200 microscope with a 20×/0.45 for Matrigel plug images. The following in the figure indicate group paired Student t-test P values: *P < .05, ***P < .001.
