RESUMEN
In 28 porcine partial thickness excisional wounds, the presence of several growth factors was first studied by enzyme-linked immunoadsorbent assay on wound fluid collected in sealed wound chambers. Basic fibroblast growth factor (bFGF) peaked on day 1 at 31.4 pg/ml; platelet derived growth factor (PDGF)-AB on day 3 reached 45.2 pg/ml, and transforming growth factor-beta (TGF-beta) on day 7 was 726.1 pg/ml. The same chamber system was used in 48 partial thickness excisional wounds for delivery of nanogram doses of bFGF, PDGF-AB, insulin-like growth factor (IGF)-1, epidermal growth factor (EGF), and cholera toxin. PDGF and EGF accelerated healing (1.1 days and 0.3 days, respectively), whereas bFGF and IGF-1 had no effect. Cholera toxin retarded healing by 1.9 days. Furthermore, in 100 excisional wounds EGF in the concentration range of 10 to 1,000 ng/ml had the same stimulating effect on healing. EGF at 10,000 ng/ml significantly delayed healing. The wound chamber model is useful for detecting of endogenous growth factors as well as for delivering exogenous factors.
Asunto(s)
Procedimientos Quirúrgicos Dermatologicos , Sustancias de Crecimiento/farmacología , Cicatrización de Heridas , Animales , Toxina del Cólera/farmacología , Relación Dosis-Respuesta a Droga , Ensayo de Inmunoadsorción Enzimática , Factor de Crecimiento Epidérmico/farmacología , Exudados y Transudados/química , Factor 2 de Crecimiento de Fibroblastos/análisis , Factor 2 de Crecimiento de Fibroblastos/farmacología , Sustancias de Crecimiento/análisis , Factor I del Crecimiento Similar a la Insulina/farmacología , Factor de Crecimiento Derivado de Plaquetas/análisis , Factor de Crecimiento Derivado de Plaquetas/farmacología , Proteínas Recombinantes/farmacología , Regeneración , Piel/patología , Fenómenos Fisiológicos de la Piel , Porcinos , Factor de Crecimiento Transformador beta/análisisRESUMEN
Effects of wet (saline in a vinyl chamber), moist (hydrocolloid dressing), and dry (sterile gauze dressing) environments on wound repair were studied in a porcine partial-thickness wound model. Chambers were exchanged and refilled daily with normal saline containing penicillin G (100 U/ml) and streptomycin (100 micrograms/ml). Hydrocolloid and gauze dressings were kept in place until biopsy of the wound site. Wounds in wet, moist, and dry environments were completely epithelialized on days 6, 7, and 8, respectively. Thickness of the epidermis in wet, moist, and dry wounds was 204 +/- 23, 141 +/- 12, and 129 +/- 18 (mean +/- SEM), respectively. Moist wounds had more subepidermal inflammatory cells than wet wounds. In comparison to dry wounds, the moist or the wet healing environment resulted in less necrosis and faster and better quality of healing in the formation of the newly regenerated epidermis.