【摘要】 目的 比较吡嗪酰胺（PZA）耐药的耐多药结核分枝杆菌在PZA药物刺激前后PZA耐药基因pncA的表达，探讨pncA基因表达与结核分枝杆菌PZA耐药的关系。方法 培养PZA耐药的耐多药结核分枝杆菌，检测其利福平和PZA最小抑菌浓度（MIC）；以PZA浓度为0和50μg/mL的培养基培养菌株，实时荧光定量PCR检测菌株pncA的表达水平。结果 21株结核分枝杆菌PZA的MIC≥1 600μg/mL、12株为400～800μg/mL、5株为100～200μg/mL；分别定义相应PZA耐药水平为高、中、低，其利福平的MIC中位数分别为128、128、64μg/mL，任意2组利福平的MIC比较差异均无统计学意义（P均> 0.05）；以相对定量2^-ΔΔCt法计算PZA高、中、低水平耐药结核分枝杆菌pncA表达水平，无药组分别为0.904（0.202,2.653）、1.157（0.658,1.511）、1.147（0.372,1.347）,PZA浓度为50μg/mL处理组分别为1.544（0.611,3.191）、0.846（0.421,1.237）、0.726（0.225,3.017）；以无药组为对照，PZA含药培养组与其对比，pncA基因表达差异无统计学意义（P> 0.05）。结论 PZA耐药的耐多药结核分枝杆菌在PZA药物刺激前后pncA表达无明显变化。更多还原

【Abstract】 Objective To compare the expression levels of pncA gene in pyrazinamide(PZA)-resistant and multidrugresistant Mycobacterium tuberculosis before and after PZA drug stimulation, and to explore the relationship between PZA-resistant Mycobacterium tuberculosis and pncA gene expression. Methods PZA-resistant and multidrug-resistant Mycobacterium tuberculosis was cultured, and the minimal inhibitory concentration(MIC) of rifampicin and PZA was detected. The strains were cultured in medium containing 0 and 50 μg/mL PZA, and the expression level of pncA was detected by real-time fluorescence quantitative PCR.Results The MIC of PZA of 21 strains of Mycobacterium tuberculosis was ≥ 1 600 μg/mL,400-800 μg/mL for 12 strains, and 100-200 μg/mL in 5 strains,and their corresponding PZA resistance levels were defined as high,medium and low,respectively. The median MIC of rifampicin was 128, 128 and 64μg/mL, respectively. Chi-square test showed that there was no significant difference between any two groups(all P > 0.05). According to the relative quantitative 2-ΔΔCt method, the expression levels of pncA in the high,medium and low levels of PZA drug-resistant Mycobacterium tuberculosis was 0.904(0.202, 2.653), 1.157(0.658, 1.511) and 1.147(0.372, 1.347), and 1.544(0.611, 3.191), 0.846(0.421, 1.237) and 0.726(0.225, 3.017) in the 50 μg/mL treatment group,respectively. There was no significant difference in pncA gene expression between the control and PZA drug-containing culture groups(P > 0.05). Conclusion No significant changes are observed in the expression levels of pncA in multidrug-resistant and PZAresistant Mycobacterium tuberculosis before and after PZA drug stimulation.更多还原