Effect of endogenous vasoactive substances on airway ciliary motility

利用培养的大鼠气管上皮细胞，研究了一氧化氮(NO)在呼吸道上皮细胞纤毛搏动频率(CBF)调节中的作用。用相差显微镜拍摄纤毛细胞的图像。NOC-12和GSNO(NO供体)、NO前体L精氨酸、8-BrcGMP、cGMP特异性磷酸二酯酶抑制剂扎普司特、β受体激动剂异丙肾上腺素、8-BrcAMP、磷酸二酯酶III型抑制剂氨力农和cAMP特异性磷酸二酯酶抑制剂罗利普兰均能增加脑血流量。L精氨酸、8-BrcGMP、异丙肾上腺素和8-BrcAMP对脑血流的增强作用可被一氧化氮合酶抑制剂L、可溶性鸟苷环化酶抑制剂ODQ或蛋白激酶G选择性抑制剂KT5823所抑制。仅L-NMMA、ODQ或KT5823不改变脑血流量。蛋白激酶A(PKA)选择性抑制剂KT5720可抑制异丙肾上腺素和8-溴-cAMP对CBF的增强作用。利用二氨基氟…生产NO研究NO的指标--More resein(DAF)及其与CBF的关系。经DAF处理的纤毛细胞呈荧光，而未经DAF处理的纤毛细胞未检测到荧光。L-精氨酸可增强细胞的荧光强度，增加脑血流量，而D-精氨酸无此作用。L-精氨酸的增强作用几乎被L-NMMA取消，而不是D-NMMA。D-精氨酸、L-NMMA和D-NMMA单独作用不改变荧光强度和脑血流量。荧光强度的增加与脑血流量呈显著正相关。这些结果表明，大鼠气管集束上皮细胞产生NO，NO以自分泌/旁分泌方式刺激CBF，NO-sGC-PKG途径参与纤毛运动的调节，该途径通过β-肾上腺素受体-cAMP-PKA途径参与CBF刺激。观察静脉麻醉剂异丙酚对脑血流量的影响。异丙酚呈剂量依赖性刺激脑血流量。异丙酚对脑血流量的增强作用可被L、异丙酚或KT5823所抑制。这些结果表明，异丙酚通过NO-sGC-PKG途径刺激脑血流。较少

The role of nitric oxide (NO) in ciliary beat frequency (CBF) regulation in airway epithelial cells were studied using cultured rat tracheal epithelial cells. Images of ciliated cells were videotaped using a phase-contrast microscope. CBF was increased by NOC-12 and GSNO (NO donors), L-arginine (a NO precursor), 8-Br-cGMP, zaprinast (a cGMP-specific phosphodiesterase inhibitor), isoproterenol (a beta-receptor agonist), 8-Br-cAMP, amrinon (a phosphodiesterase type III inhibitor) and rolipram (a cAMP-specific phosphodiesterase inhibitor). The enhancement of CBF by L-arginine, 8-Br-cGMP, isoproterenol and 8-Br-cAMP was inhibited by L-NMMA (a NO synthase inhibitor), ODQ (a soluble guanylyl cyclase (sGC)-selective inhibitor) or KT5823 (a protein kinase G (PKG)-selective inhibitor). L-NMMA, ODQ or KT5823 alone did not change CBF. The enhancement of CBF by isoproterenol and 8-Br-cAMP was inhibited by KT5720 (a protein kinase A (PKA)-selective inhibitor). The production of NO using diaminofluo … More rescein (DAF, an indicator for NO) and its relationship with CBF were studied. The ciliated cells pretreated with DAF became fluorescent, but no fluorescence was detected in the cells without the pretreatment. The fluorescent intensity and CBF increased by L-arginine, not by D-arginine. The enhancements by L-arginine were nearly abolished by L-NMMA, not by D-NMMA. D-arginine, L-NMMA and D-NMMA alone did not change fluorescent intensity and CBF. There was a significant positive correlation between the increases of fluorescent intensity and CBF. These results demonstrate that rat tracheal clliated epithelial cells produce NO, NO stimulattes CBF in autocrine/paracrine manner, the NO-sGC-PKG pathway is involved in the regulation of ciliary motility, and that the pathway is involved in CBF stimulation via the beta-adrenoreceptor-cAMP-PKA pathway. The effect of propofol, an intravenous anesthetic, on CBF was investigated. Propofol stimulated CBF dose dependently. The enhancement of CBF by propofol was inhibited by L-NMMA, ODQ or KT5823. These results demonstrate that propofol stimulates CBF via the NO-sGC-PKG pathway. Less