G. Ozcan et al., ULTRAVIOLET-A INDUCED DELAYED WOUND CONTRACTION AND DECREASED COLLAGEN CONTENT IN HEALING WOUNDS AND IMPLANT CAPSULES, Plastic and reconstructive surgery, 92(3), 1993, pp. 480-484
Chronic exposure to ultraviolet-A radiation causes changes in the bioc
hemistry of dermal connective tissue. To investigate its effects on wo
und healing, we irradiated Sprague-Dawley rats for 4 months using a bl
ack ray ultraviolet-A radiation source (560 J/cm2). Full thickness ski
n wounds of 2 cm in diameter were then created on the back of each ani
mal and silicone cubes were implanted subcutaneously into the irradiat
ed area of the back. Wound contraction in the irradiated animals (n =
28) was significantly slower than that of the controls (n = 29) (p < 0
.001). Postoperatively, the hydroxyproline content of the contracted w
ounds and the implant capsules was assessed at 6 and 12 weeks, respect
ively. In the irradiated animals, it was found to be significantly les
s than that of the controls (p < 0.001). A delay in wound contraction
and a decrease in hydroxyproline content of healing wounds and implant
capsules, reflecting an alteration in collagen metabolism, are two ef
fects of prolonged intermittent ultraviolet-A radiation pretreatment.