关键词: 内毒素类, 副作用, 中耳炎, 伴渗出液, 代谢, 肿瘤坏死因子, 分析, 白细胞介素6, 分析, 疾病模型, 动物

Abstract: Objective To study the effect and significance of bactericidal/permeability increasing protein (BPI) on the TNF-α and IL-6 mRNA expressions and protein levels in the middle ear mucosa of the rat models of otitis media with effusion (OME). Methods Rats were subjected to OME by injecting lipopolysaccharide (LPS) into middle ear cavity, and animals were divided into LPS group and BPI group. TNF-α and IL-6 mRNA expressions and their protein levels in middle ear mucosa were measured at various intervals with ELISA and RT-PCR. Results IL-6 mRNA expressions and protein levels peaked at the 1st and 2nd day in LPS group and BPI group. However, IL-6 mRNA in BPI group as well as protein levels were significantly reduced compared with LPS group（P<0.05）.There were no expressions of IL-6 mRNA and protein in the LPS group and BPI can group after 7 days. However, TNF-α mRNA expressions and protein levels persisted in LPS group and BPI group. TNF-α mRNA in BPI group as well as protein levels were significantly reduced compared with LPS group（P<0.05）. Conclusion IL-6 and TNF-α have an important role in the development of OME; BPI can prevent the expression and secretion of cytokines, reduce inflammatory activities of cytokines; BPI is a potential drug for preventing the occurrence of chronic OME.

Key words: permeability increasing protein, endotoxins, adverse effects, otitis media with effusion, metabolism, tumor necrosis factor, analysis, interleukin-6, analysis, disease models, animal