Zhu Wei-Jing, He Bei, Xu Ming
Department of Respiratory Medicine, Peking University Third Hospital, Beijing 100083, China.
Zhonghua Yi Xue Za Zhi. 2008 Aug 5;88(30):2099-102.
To investigate the relationship between beta(2)-adrenoceptor (beta(2)-AR) expression in inflammatory cells and airflow limitation in patients with chronic obstructive pulmonary disease (COPD).
According to the severity of COPD, 37 patients with stable COPD were divided into three groups. Samples of peripheral blood and induced sputum were collected from 37 COPD patients, 11 of II grade, 12 of grade III, and 14 of grade IV. Counting and classification of white blood cells in the peripheral blood and induced sputum were made. Radioligand binding assay was used to detect the maximum binding capacity (Bmax) reflecting the density, and balance dissociation constant (Kd) reflecting the affinity of beta(2)-AR in the peripheral blood mononuclear cells (PBMC) from both kinds of specimens. Thirteen normal smokers were used as control group.
No significant differences were found in peripheral blood leukocyte count, classification and induced sputum cell count among the 3 COPD groups and control group, but the neutrophil cell count levels of induced sputum of the COPD groups were all significantly higher than that of the control group (all P = 0.00). For the control, and COPD grade II, III, and IV groups, the Bmax levels of PBMC beta(2)-AR were (106 +/- 52), (156 +/- 72), (135 +/- 57) and (123 +/- 58) fmol/mg respectively (F = 1.45, P = 0.24); the Kd levels of PBMC beta(2)-AR were (548 +/- 267), (343 +/- 144), (297 +/- 150), and (375 +/- 95) pmol/L respectively (F = 4.84, P = 0.01); the Bmax levels of beta(2)-AR of induced sputum cells were (126 +/- 46), (116 +/- 54), (106 +/- 36), and (76 +/- 30) respectively (F = 3.46, P = 0.02); and the Kd levels of beta(2)-AR of induced sputum cells were (570 +/- 290), (405 +/- 197), (404 +/- 139), and (347 +/- 123) respectively (F = 2.97, P = 0.04). There was a positive correlation between the forced expiratory volume in one second in percentage of predicted and density of beta(2)-AR in induced sputum cells from the COPD patients (r = 0.43, P = 0.01). There was a positive correlation between the Bmax of beta(2)-AR in PBMC and induced sputum cells (r = 0.40, P = 0.02).
The expression of beta(2)-AR in PBMC and induced sputum cells from COPD patients is down-regulated with progression of the disease. The expression of beta(2)-AR in the induced sputum cells changes more significantly than that in the PBMC. The expression of beta(2)-AR in inflammatory cells in the airway may play a more important role in the COPD progress.
探讨慢性阻塞性肺疾病（COPD）患者炎症细胞中β₂-肾上腺素能受体（β₂-AR）表达与气流受限之间的关系。
根据COPD的严重程度，将37例稳定期COPD患者分为三组。收集37例COPD患者（Ⅱ级11例、Ⅲ级12例、Ⅳ级14例）的外周血和诱导痰样本。对外周血和诱导痰中的白细胞进行计数和分类。采用放射性配体结合试验检测两种标本中外周血单个核细胞（PBMC）中反映β₂-AR密度的最大结合容量（Bmax）以及反映亲和力的平衡解离常数（Kd）。选取13名正常吸烟者作为对照组。
3个COPD组与对照组在外周血白细胞计数、分类及诱导痰细胞计数方面无显著差异，但COPD组诱导痰中的中性粒细胞计数水平均显著高于对照组（均P = 0.00）。对照组、COPDⅡ级、Ⅲ级和Ⅳ级组PBMC的β₂-AR的Bmax水平分别为（106±52）、（156±72）、（135±57）和（123±58）fmol/mg（F = 1.45，P = 0.24）；PBMC的β₂-AR的Kd水平分别为（548±267）、（343±144）、（297±150）和（375±95）pmol/L（F = 4.84，P = 0.01）；诱导痰细胞的β₂-AR的Bmax水平分别为（126±46）、（116±54）、（106±36）和（76±30）（F = 3.46，P = 0.02）；诱导痰细胞的β₂-AR的Kd水平分别为（570±290）、（405±197）、（404±139）和（347±123）（F = 2.97，P = 0.04）。COPD患者诱导痰细胞中β₂-AR密度与预计值百分比的一秒用力呼气容积之间存在正相关（r = 0.43，P = 0.01）。PBMC与诱导痰细胞中β₂-AR的Bmax之间存在正相关（r = 0.40，P = 0.02）。
COPD患者PBMC和诱导痰细胞中β₂-AR的表达随疾病进展而下调。诱导痰细胞中β₂-AR的表达变化比PBMC更显著。气道炎症细胞中β₂-AR的表达在COPD进展中可能起更重要的作用。
