摘要
目的研究细胞因子[白细胞介素-4(IL-4),肿瘤坏死因子-α(TNF-α)]和支气管哮喘治疗药物(地塞米松,氨茶碱,沙丁胺醇)对气管上皮细胞内组胺N-甲基转移酶(HMT)活性的影响。方法培养永生化人支气管上皮细胞株BEAS-2B细胞,至细胞接近融合时分别加入不同浓度的TNF-α、IL-4、地塞米松、沙丁胺醇和氨茶碱培养24h后,用高效液相色谱法检测细胞内HMT的活性。结果气管上皮细胞内HMT的活性为(50±7)pmol.min-1.mgpro-1。TNF-α和IL-4分别在1ng/mL和5ng/mL及以上浓度时明显减低HMT的活性,10ng/mL时达到最大抑制效果。地塞米松和氨茶碱可明显抑制TNF-α所致HMT活性的降低,沙丁胺醇则无明显抑制作用。结论IL-4和TNF-α导致的HMT活性降低,可能是气道高反应性的重要原因之一;糖皮质激素和茶碱类药物抑制TNF-α所致的HMT活性降低可能是其治疗哮喘的又一作用机制。
Objective To investigate the impacts of cytokines （interleukin-4, IL-4; tumor necrosis factor-α,TNF-α） and medications of bronchial asthma （dexamethasonc, aminophylline, salbutamol） on the activity of histamine N-methyltransferase （HMT） in tracheal epithelial ceils. Methods BEAS-2B bronchial epithelial ceils were cultured and treated with different concentration of TNF-α, RM, dexamethasone, salbutamol and anfinophylline respectively. The activity of HMT in BEAS-2B cells was determined by high performance liquid chromatography. Results The activity of HMT in tracheal epithelial ceils was （50 ± 7） pmol· min^-1. mg pro^-1. TNF-α and IL-4 lowered the activity of HMT significantly at the concentration equal to or higher than 1 ng/mL and 5 ng/mL respectively,and reached the maximum inhibitory effect at the level of 10 ng/mL. Dexamethasone and aminophyllinc could meliorate distinctly the inhibitory effect of TNF-α on the activity of HMT, while saltmtamol had no significant inhibitory effect. Conclusions TNF-α and RM exert the lowering effect on the activity of HMT, which would be one important cause of airway hyperreactivity. Glueocorticoids and theophyUincs are administered to treat asthma partly due to its relieving mechanism of TNF-α negative effects on HMT.
出处
《中国呼吸与危重监护杂志》
CAS
2007年第1期19-22,共4页
Chinese Journal of Respiratory and Critical Care Medicine
