【摘要】 目的观察大鲵皮肤分泌液中抗菌肽对铜绿假单胞菌感染小鼠创面的抗菌作用。方法用5%醋酸浸提和SephadexG-50、G-25凝胶过滤层析等方法分离抗菌肽;采用Tricine-SDS-PAGE电泳鉴定,抑菌圈法检测抗菌活性;切除30只ICR小鼠背部1 cm×1 cm全层皮肤,涂抹铜绿假单胞菌菌液制成感染模型,随机均分为对照组、磺胺米隆组和抗菌肽组,伤后3 h分别用生理盐水、100 g.L-1磺胺米隆、0.5 g.L-1抗菌肽的纱布湿敷。伤前和伤后3 d抽血观察白细胞的变化;伤后每天观察小鼠创面的感染情况、精神状态和体重变化;14 d后观察小鼠的存活情况。结果检测到大鲵皮肤分泌液中抗菌肽的相对分子质量约为4.3×103 Da,对铜绿假单胞菌的抗菌活性较强;术后3组小鼠的白细胞计数均减少;对照组小鼠相比其他两组活动减少,创面潮湿、分泌物较多,磺胺米隆组、抗菌肽组的创面结痂、干燥、无明显分泌物;对照组小鼠的体重在第6天开始下降,明显少于其他两组(P<0.05);而无菌对照组的小鼠无死亡,重量持续增加。14 d后对照组存活率明显少于磺胺米隆组和抗菌肽组(P<0.05)。结论大鲵皮肤分泌液中抗菌肽对铜绿假单胞菌感染的ICR小鼠创面有较强的抗感染作用,可明显降低其死亡率。更多还原

【Abstract】 OBJECTIVE To investigate the antibacterial effect of antimicrobial peptide from the skin secretions of the Andrias davidianus on the wound of Pseudomonas aeruginosa infection in mice.METHODS This antimicrobial peptide was purified by 5%acetic acid extraction and Sephadex G-50,G-25 gel filtration chromatography.The samples were characterized by Tricine-SDS-PAGE electrophoresis and the antimicrobial activity was determined.Thirty ICR mice were enrolled in the study,and the Pseudomonas aeruginosa infection model was reproduced by excision of the full layer of dorsal skin with an area of 1 cm×1 cm.Then they were randomly divided into three groups as folloews:group C[control,n=10,treated with wet compress of isotonic saline at 3 post-injury hours(PIH)],group M(treated with wet compress of 100 g·L-1 mafenide at 3 PIH) and group A(treated with wet compress of 0.5 g·L-1 antibacterial peptide at 3 PIH).The changes of leucocytes counts in each group were also determined before and 3 days after injury.The changes of wound,mental state and weight in each group were also determined after injury.The survival of the mice were observed 14 days later.RESULTS The electrophoresis results showed the molecule weight of the antimicrobial peptide from the skin secretions of the Andrias davidianus was about 4300.Additionally the pophile showed a strong ability inhibit Pseudomonas aeruginosa.The number of leucocytes in each group was decreased after operation.The activity of mice in group C was reduced compared to the other groups,the wounds were moist with much exudation in group C.In other groups,however,the wounds were dry without obvious exudation.In addition,the weight of mice in group C decreased significanthy from 6 days after operation(P<0.05).In contrast,there was no mortality in the group without bacterial inoculation and the weight increased with time 14 days later.The survival rate in C group was evidently lower than that in the other groups(P<0.05).CONCLUSION The antimicrobial peptide from the skin secretions of the Andrias davidianus possesses obvious antimicrobial effect on the Pseudomonas aeruginosa infected wounds of ICR mice,and it can reduce the mortality.更多还原