依赖利福平结核分枝杆菌的动物实验研究

目的通过对依赖利福平结核分枝杆菌的豚鼠结核病模型研究,探讨依赖利福平结核分枝杆菌是否存在。方法豚鼠按随机数字法分成依赖利福平结核分枝杆菌(1130株、1219株、b858株)组、耐利福平结核分枝杆菌(1290株)组和对豚鼠强毒力致病株(ATCC 35810株)组,每株组再设实验组和对照组。建立豚鼠1130株、1219株、b858株、1290株和 ATCC 35810株攻毒模型,实验组用利福平治疗,对照组用生理盐水治疗,各组分别于4、7、10周观察豚鼠脏器(脾、肺、肝)致病指数、脏器重量指数(WI)、脏器(脾、肺)结核分枝杆菌培养的荷菌量及组织病理学检查。结果 1130株、1219株、1290株和 b858株攻毒豚鼠7周时,致病指数值:实验组分别为68.7±13.8、60.0±13.5、70.0±5.8和23.8±18.9,对照组分别为76.2±18.9、40.0±16.8、63.8±10.3和22.5±15.5,差异均无统计学意义(t 值分别为0.64、1.85、0.35和0.10,P 均>0.05);脾 WI 值:实验组分别为0.229±0.048、0.256±0.067、0.324±0.054和0.199±0.029,对照组分别为0.278±0.025、0.216±0.076、0.368±0.033和0.213±0.038,差异均无统计学意义(t 值分别为1.75、0.79、1.41和0.57,P 均>0.05);脾荷菌量的对数值:实验组分别为(4.98±0.30)、(4.68±1.26)、(5.07±0.47)和(3.85±0.45)CFU,对照组分别为(4.90±1.03)、(4.79±0.45)、(5.08±0.55)和(4.23±0.95)CFU,差异均无统计学意义(t 值分别为0.11、0.15、0.03和0.73,P 均>0.05),实验组和对照组的病理检查结果相似。结论依赖利福平结核分枝杆菌豚鼠结核病模型研究结果与耐利福平结核分枝杆菌株豚鼠结核病模型近似,未见明显依赖利福平现象。

The animal experimental study on rifampicin-dependent Mycobacterium tuberculosis

OBJECTIVE: To investigate the presence of rifampicin-dependent Mycobacterium tuberculosis strains by use of a guinea pig model of tuberculosis of rifampicin-dependent Mycobacterium tuberculosis. METHODS: Guinea pigs were randomly divided into groups of infection by rifampicin-dependent Mycobacterium tuberculosis strains (1130 strain, 1219 strain, b858 strain), rifampicin-resistant Mycobacterium tuberculosis strain (1290 strain) and ATCC 35810 strain and each group was further divided into an experimental group and a control group. The guinea pigs were challenged with 1130 strain, 1219 strain, b858 strain, 1290 strain and ATCC 35810 strain to establish the tuberculosis model. The experimental groups were treated with rifampicin. The parameters including macroscopic visceral pathological change index, visceral weight index (spleen, lungs and liver), the colony-forming units (CFU) quantity of visceral Mycobacterium tuberculosis culture (spleen, lungs) and tissue pathology of guinea pigs were observed. RESULTS: At the 7th week after challenged with 1130 strain, 1219 strain, 1290 strain and b858 strain, all animals were sacrificed. The macroscopic visceral pathological change indices of the experimental group were 68.7 +/- 13.8, 60.0 +/- 13.5, 70.0 +/- 5.8 and 23.8 +/- 18.9, whereas all those parameters of the control group were 76.2 +/- 18.9, 40.0 +/- 16.8, 63.8 +/- 10.3 and 22.5 +/- 15.5 respectively, and there was no significance between the experimental group and the control group (t = 0.64, 1.85, 0.35 and 0.10, all P > 0.05). The spleen weight indices of experimental group were 0.229 +/- 0.048, 0.256 +/- 0.067, 0.324 +/- 0.054 and 0.199 +/- 0.029, whereas all those parameters of control groups were 0.278 +/- 0.025, 0.216 +/- 0.076, 0.368 +/- 0.033 and 0.213 +/- 0.038 respectively, and there was no significance between the experimental group and the control group (t = 1.75, 0.79, 1.41 and 0.57, all P > 0.05). The CFU quantity of spleen Mycobacterium tuberculosis culture of the experimental group were 4.98 +/- 0.30, 4.68 +/- 1.26, 5.07 +/- 0.47 and 3.85 +/- 0.45, whereas all those parameters of control groups were 4.90 +/- 1.03, 4.79 +/- 0.45, 5.08 +/- 0.55 and 4.23 +/- 0.95 respectively, and there was no significance between the experimental group and the control group (t = 0.11, 0.15, 0.03 and 0.73, all P > 0.05); Moreover, the tissue pathology of both groups was similar. CONCLUSIONS: The tuberculosis model of rifampicin-dependent Mycobacterium tuberculosis strains was similar to the model of rifampicin-resistant Mycobacterium tuberculosis in guinea pigs. Rifampicin-dependency was not evident in this guinea pig tuberculosis model.