摘要
目的观察正常大鼠气道Toll样受体4(TLR4)的分布及脂多糖(LPS)对大鼠气道TLR4分布的影响,以及吸入不同浓度NO对TLR4表达的影响。方法气管内滴注LPS复制大鼠急性肺损伤模型,观察6h后的病理变化,免疫组化法观察气道内TLR4的变化,以及分别吸入10×10-6,20×10-6,40×10-6,100×10-6mg/L的NO对大鼠气道内TLR4mRNA表达的影响。结果免疫组化和实时荧光定量PCR结果显示TLR4在正常组大鼠气道内有广泛分布和表达。LPS急性肺损伤组大鼠病理检查显示支气管、肺内炎症程度均明显高于正常组,免疫组化及荧光定量PCR结果显示主支气管和肺内细支气管上皮细胞内TLR4表达明显升高。NO20×10-6mg/L组病理检查结果显示气管和主支气管的炎症程度明显减轻,免疫组化及荧光定量PCR结果提示肺内细支气管上皮细胞内TLR4的表达量较LPS损伤组明显降低。结论TLR4在大鼠气道内广泛分布,LPS刺激可使TLR4的表达增加,吸入适当浓度NO可降低由LPS引起的肺内细支气管上皮细胞内TLR4表达的升高。
Objective To observe the distribution of toll-like receptor 4 （TLR4） in respiratory tract of rats and study the influence of lipopolysaccharide （LPS） and inhaling nitric oxide on the distribution of TLR4. Methods The Sprague-Dawley rats were intratracheally instilled with LPS （5 mg/kg） to induce acute lung injury （ALI）. At 6 h after LPS instillation and inhalation of different doses of nitric oxide （NO）, lung morphological changes were studied. The expression of TLR4 was detected by immunohistochemistry and fluorescent quantitative PCR （FQ-PCR）. Results The results of immunohistochemistry and FQ-PCR showed that TLR4 distributed widely in respiratory tract of normal rats. In the group of ALI, the inflammation in bronchus and bronchioles was more apparent than in the control group in morphology, and the expression of TLR4 was increased in main bronchus and bronchioles. In the inhalation group of 20 ×106^-6 mg/L NO, the inflammation was lessened and the expression of TLR4 decreased as compared with the group of ALI model. Conclusion TLR4 distributes widely in respiratory tract of rats. The stimulation of LPS can increase the expression of TLR4. Inhaling low level of NO （20 ×106^-6 mg/L） can reduce the increase of TLR4 induced by LPS in bronchioles.
出处
《华中科技大学学报（医学版）》
CAS
CSCD
北大核心
2008年第5期583-586,701,共5页
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
基金
湖北省自然科学基金资助项目(No.2006ABA145)
