家蝇幼虫分泌型抗菌肽对细菌感染小鼠的影响

目的:探讨家蝇幼虫分泌型抗菌肽对细菌感染小鼠的影响.方法:选用BALB/c小鼠,随机分为3组:抗菌肽预防性干预组(小鼠感染前3d预防性给抗菌肽10 mg·kg-1·d-1)、治疗性干预组(感染后予抗菌肽10 mg·kg-1)和模型组(感染后予生理盐水),小鼠细菌感染方式为ip大肠杆菌液,给抗菌肽方式亦为ip给药,设正常小鼠为对照.分别检测以下指标:感染后4,12 h各组小鼠腹腔液细菌数量；感染后4,8,12,24 h小鼠外周血内毒素、一氧化氮(NO)含量及鼠肿瘤坏死因子-α(TNF-α),白细胞介素-6(IL-6)等细胞因子水平.结果:预防性给抗菌肽能明显减少小鼠腹腔液的细菌数量,同时小鼠外周血TNF-α,IL-6,NO及内毒素含量均明显低于模型组；治疗性给抗菌肽组小鼠腹腔液细菌数及外周血内毒素含量亦明显低于模型组,但对其他指标的干预作用较预防性给抗菌肽组弱.结论:家蝇幼虫分泌型抗菌肽ip给药对大肠杆菌ip感染小鼠具有一定的抑制作用.

Effect of Secreting Type Antibacterial Peptides from Musca domestica in Mice with Abdominal Infection

Objective:To study the effect of secreting type antibacterial peptides from Musca domestica Larvae in mice with abdominal infection.Method: Thirty-two BALB/c mice were selected and divided randomly into four groups.Experiment group 1(prophylactic intervention of antibacterial peptide): 10 mg·kg-1·d-1 antibacterial peptide was administered prophylactic before bacterial infection for 3 days.Experiment group 2(remedial intervention of antibacterial peptide): 10 mg·kg-1 antibacterial peptide was administered after bacterial infection.Model group: normal sodium was administered after bacterial infection.Normal mice were control.The number of bacteria in ascitic fluid was examined in 4 h and 12 h after bacterial administration.These contents were measured of plasma Tumor nercosis factor-alpha(TNF-α),interleukin-6(IL-6),nitric oxide(NO) and endotoxin in 4,8,12 h,and 24 h after bacterial infection.Result: There was a distinct content decrease of plasma TNF-α,IL-6,NO and endotoxin in antibacterial peptide pretreatment group compared with those in model group.In remedial intervention group,bacterial number in ascitic fluid and endotoxin content in peripheral blood were obviously lower than those in model group,while changes of other indexes were not as obvious as those in pretreatment group.Conclusion: The secreting type antibacterial peptides from M.domestica could show the immunoregulation in bacterial infection mice.