Total body γ-irradiation decreases wound breaking strength during wound healing in rats

Abstract

Objective To investigate the influence of total body irradiation with different doses of 60Coγ on wound breakingstrength during wound healing in rats. Methods Rats were exposed to 60Coγ radiation at dosages of 4,6,and 8 Gy. Within 30 min afterirradiation,full thickness skin wounds were made on the shaved back of rats to establish animal models of irradiated-trauma injury plusskin wounds ( n =20) ,and non-irradiated rats with pure incision injury were used as controls ( n =10) . The rats were sacrificed at day 10after treatment,and the full thickness skin wounds were harvested. Bio-mechanics method and histopathology examination were used toevaluate the wound breaking strength and histological features after healing. Results The wound breaking strength of model groups weregreatly retarded with the increase of irradiation doses. Statistical results showed that on day 10 the wound breaking strength values weresignificantly different between 4 Gy group ( [114. 26 ± 0. 29] g) and control group ( [117. 12 ± 1. 86] g,P 0. 05) ,and the woundbreaking strength values of 6 Gy group ( [91. 87 ±1. 96]g) and 8 Gy group ( [55. 26 ±2. 64]g) were significantly lower than that of thecontrol group ( P 0.05) . H-E staining showed that the wounds in the irradiation trauma groups had looser and disorder collagenous fiber andless fibroblast proliferation than control group. Conclusion Radiation injury may result in delayed wound healing,and the wound breakingstrength decreases with the increase of irradiation dose in model of irradiation injury plus full thickness skin wounds.