目的建立大鼠导管相关性黏液型铜绿假单胞茵生物被膜感染模型,探讨氨溴索对黏液型铜绿假单胞茵生物被膜的体内干预作用。方法建立铜绿假单胞茵临床分离株BF体外模型,培养7d后得到成熟BF。将BF植入大鼠气管建立大鼠导管相关性黏液型铜绿假单胞菌生物被膜感染模型,分为BF感染组,BF氨溴索干预组,空白导管对照组和正常对照组。分别在植入后第4天和第7天处死大鼠,取出导管通过扫描电镜观察导管上BF的结构改变,检测导管上细菌及藻酸盐的含量;并检测肺组织匀浆和血浆中藻酸盐抗体含量。结果成功建立大鼠导管相关性黏液型铜绿假单胞菌生物被膜感染模型。在术后4d和7d两个时间点BF感染氨溴索干预组大鼠气管导管上的BF结构被破坏,在术后4d和7dBF感染氨溴索干预组和BF感染组茵落计数分别为(8.3494±0.025)IgCFUVS(8.5669-t-O.11)lgCFU和(8.15274-0.015)lgCFUVS(8.5009±0.013)lgCFU(F=87.6和F=507.5,P〈0.05)。BF藻酸盐的含量也减少,术后4d和7dBF感染氨溴索干预组和BF感染组藻酸盐含量分别为(55.3776±0.842)mg/gVS(83.4886±0.538)mg/g和(42.3721.4-0.505)mg/gVS(74.6215±0.215)mg/g(F=791.7和F=3450.9,P〈0.05)。BF感染氨溴索干预组和BF感染组的血浆抗藻酸盐抗体含量在两个时间段分别为(0.7721±0.006)VS(1.0005±0.006)和(0.79174-0.007)VS(1.0195±0.007)(F=351.9和844.5,P〈0.05)。结论氨溴索可破坏大鼠气管导管上的BF结构,减少导管上BF内的细菌和BF藻酸盐的含量。氨溴索可降低抗藻酸盐抗体的表达,战轻肺部免疫损伤。
Objective To establish murine model of tube - associated lung infection caused by Pseudomonas aeruginosa with biofilms (BF) formation, further to explore the effect of ambroxol on the mucoid Pseudomonas aeruginosa biofilms in vivo. Methods Plate culture method was used to establish BF model of Pseudomonas aeruginosa in vitro. Tube with BF formation was planted into trachea and murine model of tube - associated lung infection caused by Pseudomonas aeruginosa with biofilms formation was established. Rats were allocated into 4 groups ran- domly:Group 1 ,rats with biofilm-covered tube intubation were given ambroxol;Group 2, rats with biofilm-covered tube intubation were given saline as control ; Greup 3, rats with sterile tube intabation were given saline as control ; Group 4, rats without any operation as normal control. The rats were sacrifced on the 4th and 7th day after intubation respectively. Tubes were drawn out to investigate the structure of BF with scanning electron microscopy and detect the content of alginate and bacterial count. Meantime anti-alginate IgG was determined using enzyme- linked immunosorbent assay (ELISA). Results Murine model of tube associated lung infection caused by Pseudomonas aeruginosa with BF formation was successfully established. The structure of BF was destroyed. Bacterial count in BF of Group 1 and Group 2 were 8. 349 4 ± 0. 025 lgCFU vs 8. 566 9 ±0. 11 lgCFU and 8. 152 7 ±0. 015 IgCFU vs 8. 500 9 ±0. 013 lgCFU on day 4 and day 7 after infection respectively ( F = 87.6 and F = 507.5, P 〈 0. 05 ). The contents of alginate in Group I and Group 2 were 55. 377 6 ± 0. 842 mg/g vs 83. 488 6 ±0. 538 mg/g and 42. 372 1 ± 0. 505 mg/g vs 74. 621 5 ± 0. 215 mg/g on day 4 and day 7 respectively, ( F = 791.7 and F = 3 450.9, P 〈 0.05). Anti-alginate IgG level in Group 1 and Group 2 were 0. 772 1 ±0. 006 vs 1. 000 5 ±0. 006 on day 4 after infection and 0. 791 7± 0. 007 vs 1. 019 5 ± 0. 007 on day 7 after infection ( F = 351.9 and 844.5, P 〈 0. 05. Conclusi