Phases of the cutaneous angiogenesis process in experimental third-degree skin burns: histological and immunohistochemical study

摘要

Skin burns represent a major problem of public health because of their frequency and because of their seriousness, too. The healing process of the burnt wound is extremely complex, as it requires a well-coordinated collaboration among different tissues and cellular strings. From the morphological point of view, the stages of the repairing process of the skin wounds include processes of inflammation, proliferation and tissular remodeling. Angiogenesis has a role of extreme importance within the healing process of third-degree skin burns. That is because the vascularization remake is necessary for feeding the tissue of granulation with nutritive substances and oxygen. The angiogenesis started relatively fast. Three days after the producing of the burn, there could be identified strings of CD34+ endothelial precursor cells at the edges and deep into the wound, all these having contact with the normal blood vessels or with those lees affected by the thermal aggression. After the lumenization of the newly-formed capillary vessels, there appeared the pericytes within their membrane. The CD34+ endothelial precursor cells (EPc), as well as the pericytes, participate at the synthesis of the base membrane of the angiogenesis vessels. The density of the angiogenesis vessels on the surface unit within the tissue of granulation grew from three to 12 days. After that, they reduced progressively while the tissue of granulation was becoming mature. The angiogenesis vessels go through a process of reshuffling and maturation at the same time with the maturation of the tissue of granulation, but these processes did not appear to be finished when the skin was completely healed, and the epidermis was totally recovered.