硝酸甘油对哮喘患者一氧化氮内皮素的影响及机制

Effects of nitroglycerin on nitric oxide and endothelin derived from bronchial epithelial cells and alveolar macrophages in asthma

目的 了解哮喘患者肺泡巨噬细胞（ＡＭ） 、支气管上皮细胞（ＢＥＣ） 源性一氧化氮（ＮＯ）、内皮素（ＥＴ）的分泌状态及硝酸甘油（ＮＴＧ）对哮喘患者ＡＭ、ＢＥＣ产生ＮＯ、ＥＴ的影响及机制。方法 分离纯化了１５ 例轻、中度哮喘发作期患者、７ 名健康受试者ＡＭ、ＢＥＣ，并分为哮喘未干预组、哮喘ＮＴＧ干预组和健康对照组，用放射免疫法和镀铜镉还原法分别测定ＡＭ、ＢＥＣ培养４８ 小时上清液中ＥＴ、ＮＯ·２／ＮＯ·３ 浓度，用原位杂交的方法检测ＡＭ、ＢＥＣｉＮＯＳｍＲＮＡ、ＥＴｍＲＮＡ 的表达。结果 （１） 健康受试者ＡＭ、ＢＥＣ分泌少量ＮＯ和ＥＴ及少量ｉＮＯＳｍＲＮＡ 、ＥＴｍＲＮＡ表达；（２）哮喘患者ＡＭ、ＢＥＣ源性ＮＯ、ＥＴ水平及ＡＭ、ＢＥＣｉＮＯＳｍＲＮＡ、ＥＴｍＲＮＡ表达与各组比较差异有显著性（ Ｐ均＜ ０－０５）；（３）ＮＴＧ 促进哮喘患者ＡＭ、ＢＥＣ源性ＮＯ产生（ Ｐ均＜０－０５），明显抑制ＥＴ产生和ＥＴｍＲＮＡ 的表达，与对照组比较差异均无显著性（ Ｐ均＞ ０－０５） ，ＮＴＧ同时抑制哮喘患者ＡＭ、ＢＥＣｉＮＯＳｍＲＮＡ的表达，与健康对照组、哮喘未干预组比较差异有显著性（Ｐ均＜０－０５） ；（４）

Objective To investigate the changes of nitric oxide(NO) and endothelin(ET) derived from alveolar macrophages(AM) and bronchial epithelial cells (BEC), and the influences of nitroglycerin (NTG) on ET and NO in asthma Methods BEC and AM from 15 patients with asthma exacerbation and 7 healthy control subjects were isolated and cultured for 48 hours NO and ET levels in supernatants and expressions of iNOS mRNA and ET mRNA from cultured BEC and AM were examined by copper coated cadmiunm reduction, radioimmunoassay and in situ hybridization Results The NO level and the ET level in supernatants, and expressions of iNOS mRNA and ET mRNA from BEC and AM of the untreated group were higher than those of other groups ( P <0 05, respectively); The NO level from BEC and AM in supernatants of NTG pretreated group were elevated significantly and the ET level and the expression of iNOS mRNA and ET mRNA were lower than those of asthma untreated group ( P <0 05, respectively) ; The NO, ET levels and expressions of iNOS mRNA, ET mRNA derived from AM were higher than those derived from BEC in patients with asthma ( P <0 05 , respectively); expression of iNOS mRNA from BEC and AM were negatively correlated with the NO level in supernatants of cultured BEC and AM from the group pretreated by NTG in asthma ( r =-0 60, r =-0 59; P <0 01). While the expression of iNOS mRNA and ET mRNA by BEC and AM from other groups were positively correlated with the NO level and the ET level in supernatants of BEC and AM in asthma (all r ≥0 902; P < 0 01, respectively) Conclusions BEC and AM from patients with asthma exacerbation secreted a large quantity of NO and ET because of the increased expressions of iNOS mRNA and ET mRNA; AM was the main source of elevated NO and ET in airways of patients with asthma exacerbation NTG directly enhanced the production of NO and significantly inhibited the expression of ET mRNA, and therefore decreased the production of ET