Yoshioka I, Himi T, Kataura A
Department of Otolaryngology, Sapporo Medical University, School of Medicine, Japan.
Acta Otolaryngol. 1997 Sep;117(5):719-23. doi: 10.3109/00016489709113466.
Interleukin-8 possesses chemotactic-activating properties toward neutrophils, and may contribute to the pathogenesis of middle ear inflammation. GRO/CINC-1 is a rat chemokine with structural and functional homology to human interleukin-8, the induction and regulation of which in the middle ear cavity in vivo remains to be established. The production of GRO/CINC-1 in middle ear lavage and gene expression in the middle mucosa was investigated using topical inoculation with lipopolysaccharide (LPS) in the rat in vivo model. GRO/CINC-1 in middle ear lavage showed time- and dose-dependent production under LPS stimulation. The peak of the GRO/CINC-1 production was reached by 4 h after LPS 1 h exposure, whereas the level of production subsequently returned to the level without LPS stimulation at 8 h after LPS stimulation. The topical corticosteroid perfusion in the middle ear after LPS stimulation significantly reduced the production of GRO/CINC-1 in the middle ear cavity compared with that without corticosteroid. At the time of peak production, the expression of GRO/CINC-1 mRNA, evaluated using the polymerase chain reaction, was considerable in the middle ear mucosa. This investigation of the characteristics of interleukin-8-like cytokine in the middle ear cavity using a rat in vivo model has extended the functional concept of chemokines at the initial stage in otitis media.
白细胞介素-8对中性粒细胞具有趋化激活特性，可能参与中耳炎症的发病机制。GRO/CINC-1是一种大鼠趋化因子，与人类白细胞介素-8在结构和功能上具有同源性，其在体内中耳腔中的诱导和调节情况尚待确定。在大鼠体内模型中，通过局部接种脂多糖（LPS）来研究中耳灌洗中GRO/CINC-1的产生及中耳黏膜中的基因表达。在LPS刺激下，中耳灌洗中的GRO/CINC-1呈现出时间和剂量依赖性产生。在LPS暴露1小时后4小时达到GRO/CINC-1产生的峰值，而在LPS刺激后8小时，其产生水平随后恢复到无LPS刺激时的水平。与未使用皮质类固醇的情况相比，LPS刺激后中耳局部灌注皮质类固醇显著降低了中耳腔中GRO/CINC-1的产生。在产生峰值时，使用聚合酶链反应评估，中耳黏膜中GRO/CINC-1 mRNA的表达相当可观。使用大鼠体内模型对中耳腔中白细胞介素-8样细胞因子特性的这项研究扩展了中耳炎初始阶段趋化因子的功能概念。
