强功率UVA1照射对增生性瘢痕动物模型瘢痕形成的影响  

Effects of UVA1 radiation on the formation of hypertrophic scar in rabbits

作　　者：张彤[1] 夏群力[1] 郑捷[1] 

机构地区：[1]上海交通大学医学院附属瑞金医院皮肤科,200025

出　　处：《中华皮肤科杂志》2008年第6期367-370,共4页Chinese Journal of Dermatology

基　　金：上海市教育发展基金会产学研基金（2005）

摘　　要：目的探讨不同剂量UVA1对全层皮肤缺损诱导的兔耳增生性瘢痕模型的影响情况。方法18只新西兰白兔双耳腹面手术切除2cm×5cm全层皮肤至筋膜，建立兔耳增生性瘢痕模型后，随机分成3组，每组6只兔，将每只兔左耳分别于伤后即刻、1个月、2个月开始用不同剂量大功率UVA1照射，右耳为非照射组。各照射组又分为两个剂量照射组，兔耳分别每次照射UVA1 60J／cm^2、110J／cm^2，连续30次。结果创伤建模1个月、2个月后开始照射UVA1组，与照射前比较，高剂量组照射后瘢痕处真表皮厚度（282．32±58．60；336．50±98．34）和真皮胶原含量（24．91±16．88；34．47±8．90）均显著降低（P〈0．05）；照射组与非照射组在UVA1照射前后差值的比较，高剂量组照射后瘢痕处表真皮厚度差值（-143．52±42．91；-142．44±49．96）和真皮胶原含量差值（-56．39±15．04；-48．35±10．44）的差异有统计学意义（P〈0．05）；各照射组UVA1对瘢痕皮肤厚度（811．68±79．03；659．08±178．98）和胶原含量（67．80±9．06；61．35±12．91）的影响均存在剂量依赖性（P〈0．05）。而创伤建模的同时照射UVA1组，两种剂量的UVA1照射后瘢痕处皮肤厚度和胶原含量较非照射耳均显著增加（P〈0．05）。结论上皮化后开始UVA1照射可使瘢痕变软，皮肤变薄，胶原含量降低。创伤同时照射UVA1不仅不能阻止瘢痕模型的建立，反而加重瘢痕。Objective To study the effects of different doses of UVA1 on the development of hypertrophic scar in rabbit ears induced by excision of full-thickness skin. Methods A hypertrophic scar model was established by excision of full-thickness skin （2 cm × 5 cm） on the ventral surface of rabbit ears. A total of 18 New Zealand rabbits were randomly divided into 3 equal groups to receive UVAI radiation on the left ears immediately, 1 month, and 2 months after the excision, respectively, and every group were classified into two subgroups to be irradiated with 60 and 110 J/cm^2 of UVAI, respectively, for 30 sessions. The right ears served as control without irradiation. HE staining and Masson staining were used to examine the dermal thickness and collagen content in scar, respectively. Results Compared with pre-irradiation, the dermal thickness （ t = 5.85, 4.94, respectively, both P 〈 0.05） and collagen content （ t = 6.50, 8.02, respectively, both P 〈 0.05 ） significantly decreased in scar irradiated with UVAI of 110 J/cm^2 one and two months after the excision. The difference value in dermal thickness and collagen content at the beginning and at the end of the study significantly differed between irradiated and non-irradiated ears in the rabbits treated with UVAI of 110 J/cm^2 （P 〈 0.05 ）. The effects of UVAI on dermal thickness and collagen content were dose-dependent （P 〈 0.05 ）. On the contrary, the dermal thickness and collagen content markedly increased in scars of rabbits irradiated with UVAI immediately after the excision （P 〈 0.05）. Conclusions To begin UVAI exposure of hypertropic scar in rabbits after epithelialization may lead to the softening of scar, thinning of skin, and decrease of collagen content. However, immediate irradiation with UVA 1 after wound could not prevent the development of hypertrophic scar in rabbits, in contrast, it exacerbated the severity of scar.

关 键 词：瘢痕 紫外线 疾病模型 动物 

分 类 号：R622[医药卫生—整形外科]