Alberty Jürgen, August Christian, Stoll Wolfgang, Rudack Claudia
Department of Otorhinolaryngology, University of Münster, Münster, Germany.
Laryngoscope. 2004 Sep;114(9):1642-7. doi: 10.1097/00005537-200409000-00026.
OBJECTIVES/HYPOTHESIS: Endogenous nitric oxide (NO) production by inducible nitric oxide synthase is enhanced in the nasal ciliated respiratory tract epithelium of patients with allergic rhinitis. Recent experimental data have suggested endogenous NO to be strongly involved in the complex regulation of ciliary activity, the driving force of the mucociliary transport system. The authors investigated the effect of endogenous NO on acetylcholine-stimulated ciliary activity of human nasal mucosa.
In vitro study.
Cultures of human nasal mucosa explants were incubated with tumor necrosis factor-alpha and bacterial lipopolysaccharides to enhance endogenous NO production. Expression of inducible NO synthase was morphologically demonstrated by immunohistochemistry. Ciliary beat frequency was determined by phase-contrast microscopy of ciliated epithelium, using a computerized photoelectric technique. Stimulation experiments were performed in vitro with acetylcholine and N(G)-nitro-l-arginine methyl ester (L-NAME), a NO synthase inhibitor.
Upregulation of inducible NO synthase in the respiratory tract epithelium after stimulation with tumor necrosis factor-alpha and lipopolysaccharide was visualized by immunohistochemical analysis. Experimental inhibition of enhanced endogenous NO production by 10 mol/L L-NAME significantly reduced baseline ciliary beat frequency from 8.6 +/- 0.2 to 7.8 +/- 0.2 Hz (P < .05). Cholinergic ciliary stimulation above baseline by 10 mol/L acetylcholine was not significantly different before (11.5%) or after (10.8%) blocking of endogenous NO production.
Taken together, the study results suggest that baseline ciliary activity depends on endogenous NO production but that the extent of cholinergic ciliary stimulation is independent of endogenous NO production. The combination of the two effects may improve nasal mucociliary clearance of inhaled allergens in patients with allergic rhinitis.
目的/假设：变应性鼻炎患者鼻纤毛呼吸道上皮中，诱导型一氧化氮合酶产生的内源性一氧化氮（NO）生成增加。近期实验数据表明，内源性NO在纤毛活动的复杂调节中起重要作用，而纤毛活动是黏液纤毛转运系统的驱动力。作者研究了内源性NO对人鼻黏膜乙酰胆碱刺激的纤毛活动的影响。
体外研究。
将人鼻黏膜外植体培养物与肿瘤坏死因子-α和细菌脂多糖一起孵育，以增强内源性NO生成。通过免疫组织化学在形态学上证实诱导型NO合酶的表达。使用计算机化光电技术，通过纤毛上皮的相差显微镜确定纤毛摆动频率。体外使用乙酰胆碱和NO合酶抑制剂N(G)-硝基-L-精氨酸甲酯（L-NAME）进行刺激实验。
免疫组织化学分析显示，用肿瘤坏死因子-α和脂多糖刺激后，呼吸道上皮中诱导型NO合酶上调。10 μmol/L L-NAME对增强的内源性NO生成的实验性抑制使基线纤毛摆动频率从8.6±0.2显著降低至7.8±0.2 Hz（P<.05）。在阻断内源性NO生成之前（11.5%）或之后（10.8%），10 μmol/L乙酰胆碱引起的高于基线的胆碱能纤毛刺激无显著差异。
综上所述，研究结果表明基线纤毛活动依赖于内源性NO生成，但胆碱能纤毛刺激的程度与内源性NO生成无关。这两种作用的结合可能改善变应性鼻炎患者吸入变应原的鼻黏液纤毛清除。
