SD大鼠烫伤铜绿假单胞菌感染模型的建立

Establishment of Pseudomonas aeruginosa infected model on burn wound SD rats

目的以新型台式超级控温烫伤仪建立SD大鼠烫伤铜绿假单胞菌感染模型,并采用磺胺嘧啶银乳膏验证其用于外用烫伤感染制剂的评价效果。方法采用台式超级控温烫伤仪建立SD大鼠接触性烫伤模型(单纯烫伤组),烫伤20 min后,以1×109 CFU/ml铜绿假单胞菌涂抹于大鼠创面(0.1 ml/只),建立烫伤感染模型(烫伤感染组)。在烫伤感染组基础上,给予磺胺嘧啶银乳膏,一日1次,涂抹于创面,厚度约为1.5 mm(磺胺嘧啶银组)。记录或检测大鼠创面起痂时间、愈合面积、痂下铜绿假单胞菌数量及病理组织学等指标评价模型。结果与单纯烫伤组相比,烫伤感染组大鼠创面起痂时间显著延长,创面愈合缓慢,创面收痂面积明显减小,创面组织上铜绿假单胞菌数显著增多,差异均具有统计学意义(P<0.05)。与烫伤感染组相比,磺胺嘧啶银组上述各项指标均明显改善,差异均具有统计学意义(P<0.05,P<0.01)。HE染色结果表明,烫伤感染组血管扩张,皮肤表皮坏死,炎症细胞浸润明显,而磺胺嘧啶银组上述症状均有明显改善。结论本研究建立的烫伤铜绿假单胞菌感染模型具有一定的敏感性和有效性,可用于外用烫伤感染制剂的评价。

Objective To establish a burn wound Pseudomonas aeruginosa infected SD rats model by electrical scald instrument, and to verify the model by silver sulfadiazine for evaluate of topical scald preparations. Methods The rats were injured by the electrical scald instrument as simple burn wound group.The wounds were infected with 1 x 10^9 CFU/ml Pseudomonas aeruginosa bacterial solution as bum wotmd infection group. The burn wound infection group was given silver sulfadiazine cream once a day, and the thickness was 1.5 mm （silver sulfadiazine group）. Scar formation, wound healing, the number of bacteria and histology were evaluated. Results In burn wound infection group, the time of scar formation was longer, wound healing area was smaller, the numbers of bacteria were more than those in simple burn wound group, the differences were significant （P〈0.05）. Compared with burn wound infection group, all of those symptoms were improved in silver sulfadiazine group, the differences were significant （P〈0.05, P〈0.01）. The HE staining in burn wound infection group showed the vasodilation, skin epidermal necrosis and inflammatory cell infiltration significantly, which were improved insilver sulfadiazine group. Conclusion The bum wound infection model is sensitive and effective. It is an available model to evaluate the topical scald preparations.