The murine excisional wound model: Contraction revisited.

Rodent models of healing are considered limited because of the perception that rodent wounds heal by contraction while humans heal by reepithelialization The purpose of this report is to present evidence that simple murine excisional wounds provide a valid and reproducible wound model that heals by both contraction and reepithelialization. Previous studies have shown that, although rodent wounds contract by up to 80%, much of this contraction occurs only after epithelial closure. To confirm these previous findings, we measured re-epithelialization and contraction in three separate mouse strains, (BALB/c, db/+, and db/db); reepithelialization and contraction each accounted for ∼40 to 60% of the initial closure of full thickness excisional wounds. After closure, the wound continues to contract and this provides the impression of dominant closure by contraction. In conclusion, the simple excisional rodent wound model produces a well defined and readily identifiable wound bed over which the process of reepithelialization is clearly measurable.