家兔细菌性脑膜炎模型的建立

Establishment of Rabbit Model of Bacterial Meningitis

目的:探讨细菌性脑膜炎(BM)模型制作方法。方法:将24只家兔随机分为实验组和对照组,实验组经小脑延髓池穿刺采集脑脊液0.5 m l,之后于小脑延髓池内接种具有K1抗原的大肠埃希菌(EC)悬液0.2 m l(8×107CFU/m l),对照组小脑延髓池注射灭菌生理盐水0.2 m。l分别于注射悬液/生理盐水前及注射后6、12和24小时经小脑延髓池穿刺采集脑脊液0.5 m l测定有关指标,之后处死取脑分别测定脑组织含水量及观察组织形态学改变。结果:实验组接种前脑脊液无细菌生长,接种后12小时脑脊液培养出与接种同株的EC;对照组注射生理盐水前后脑脊液培养均无菌生长。实验组脑组织含水量明显增加,肉眼可见脑实质水肿,脑室和脑池有脓性渗出物,光镜下可见蛛网膜下腔增宽,其中有大量中性粒细胞浸润;对照组未见上述病理改变。小脑延髓池穿刺术简单易行。结论:经小脑延髓池接种具有K1抗原的EC建立家兔BM模型简单、可靠。

Objectlve：To explore the method for establishing animal model of bacterial meningitis. Methods：24 rabbits were randomly divided to meningitis group and control group. 0.5 ml cerebrospinal fluid （CSF） was collected from each rabbit in meningitis group via verebellomedullary cistern puncture. And then 0. 2 ml suspension containing Escherichia coli with K1 antigen （8 × 10^7 CFU/ml）was injected into the cistern slowly,while 0. 2 ml normal saline was injected into the cistern in controls. At the 6th, 12th and 24th hour after the injections,0. 5 ml CSF was collected from each animal in the two groups and bacterial culture was performed. Then the rabbits were killed and their brain tissue was removed for determining brain water content and morphological changes observation. Results： No bacterium in CSF was found before inoculation of E coli in meningitis group, but the same E coli strain in CSF as the inoculated E coli was cultured at the 12th hour of the inoculation; there was no bacterium in CSF from controls before and after injecting normal saline. In meningitis group, water content in brain tissue was increased markedly with macroscopical brain parenehyma edema. Purulent exudate was encountered in cerebral ventricles and cisterns;microscopically,broadened subarachnoid space with neutrophil infiltration was revealed. No such morphological changes were demonstrated in control group. Cerebellomedullary cistern puncture was simply and easy performed. Conelusion：Cerebellomedullary cistern injection was an easy and reliable method for establishing rabbit model of bacterial meningitis.