摘要
目的建立新生SD大鼠细菌性脑膜炎(BM)动物模型。方法11日龄新生SD大鼠分为实验组(n=30)、正常对照组(n=10)和生理盐水对照组(n=10)。实验组经小脑延髓池分别接种不同浓度B组链球菌Ⅲ(GBSⅢ)10μL,生理盐水对照组用生理盐水替代GBSⅢ,正常对照组不作处理。观察发绀、呼吸困难等临床症状及最早出现的症状和时间点。采用Loeffler的评分方法作行为评分。根据Racine的抽搐分级标准进行抽搐评价。脑脊液(CSF)作WBC计数、细菌培养,作心血细菌培养。观察脑组织病理学改变,作细胞凋亡检测。结果实验组出现所观察的全部临床症状,最早于感染后6h出现发绀;神经行为学评分低于对照组(P<0.01);多数出现抽搐(21/30),其分级均在Ⅳ级以上;CSF的WBC计数高于对照组(P<0.05);CSF和心血培养出的细菌与接种细菌相同;神经细胞出现坏死和凋亡,凋亡指数为15.92±5.36%。对照组均无临床症状,细菌培养阴性,脑组织病理学检查正常。结论11日龄SD新生大鼠经小脑延髓池接种GBSⅢ,可成功地制作BM动物模型。
[Objective] To induce an neonatal rat model of bacterial meningitis, in order to supply rehable experimental evidence for the pathogenesis of bacterial meningitis of neonate. [Methodsl Sprague-Dawley rats on postnatal day 11 were divided into experimental groups （n=30）, normal control （n=10） and normal saline control （n= 10） randomly. The experimental groups were infected by direct intracistornal injection different size of suspension of GBSⅢ10 μL, the normal saline controls group were injected NS instead of GBS Ⅲ, the normal controls weren＇t injected anything. The rats were observed the clinical manifestations （such as cyanosis,dyspnea and so on ） and the earliest symptom and the timepoint when clinical symptom happened. To score according to the method come from Loeffler＇s neuroethology score for the rat. The convulsive rats were evaluated by the standard of seizures for the rats come from Racine. Meanwhile white blood cell（WBC）count and bacterial culture in the cerebrospinal fluid （CSF） and bacterial culture in the heart-blood were assessed. Then observe the changes of brain tissue, do HE stain and Nissl stain in the brain pathological section, and check the apeptosis cell. [Results] The neonatal rats in the experiment groups showed all clinical nlanifestation. The earliest timepeint we observed cyanopathy in the neonatal rats is 6 h. The score of neuroethology is lower than control groups （P 〈0.01）. Most of the rats convulsive （26/30）, the grading is over IV; the white blood cell count in the CSF is higher than control groups （P 〈0.05）. The bacteria in the CSF and the heart-blood culture were the same as the one which was injected in the cerebellomedullary cistern. In the histopathologic studies, we observed congestion and edema in the brain, there were inflammatory ceils invading into the subarachnoid space, Neurons showed morphological characteristics of apeptosis and necrosis. The index number is （15.92±5.36） %. The control groups had no clinical symptom, bacteria culture were negative, the histopathologic studies of brain were nomlal. [Conclusions] Bacterial meningitis can be induced by direct intracistemal injection of a suspension of GBSⅢ on postnatal day 11 in neonatal SD rats.
出处
《中国现代医学杂志》
CAS
CSCD
北大核心
2006年第19期2891-2896,共6页
China Journal of Modern Medicine
基金
湖南省卫生厅科研基金(Y02-050)
