生物波调控因子对脑梗死大鼠脑组织TNF-α表达的影响

Effects of Bio-wave Regulation Factor on Tumor Necrosis Factor-α Expression in Rats after Middle Cerebral Artery Occlusion

目的探讨生物波调控因子(Bio-wave regulation factor,BRF)对大鼠局灶性脑缺血损伤后行为学及脑组织内肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)表达的影响。方法成年健康雄性SD大鼠90只随机分为3组,即假手术组、生理盐水组、BRF治疗组,每组分为6、24、48、72h、7d,5个亚组,每亚组6只大鼠。参照Longa等的线栓法制成大脑中动脉闭塞(middle cerebral artery occlusion,MCAO)模型,术后1h以1ml/100g体重的剂量分别腹腔注射1.25%BRF溶液和生理盐水,此后1次/d重复注射,至相应时间点处死动物。采用Longa等4种方法进行行为学评分、干湿重法测定脑组织含水量、HE染色观察组织病理学改变、免疫组织化学方法观察脑组织TNF-α的动态变化。结果1.行为学评分:MCAO大鼠对侧肢体存在不同程度瘫痪,在术后48h和72h神经功能缺损最为明显,7d基本恢复正常;2.脑组织含水量测定:脑梗死组脑组织含水量在各时间段均增加,其中术后48hBRF组低于同期的生理盐水组(P<0.05);3.脑组织HE染色观察:除假手术组外,其余各组在脑梗死后6h局部可见炎性细胞浸润,48h明显增多,并持续到7d;4.脑组织TNF-α的表达:与假手术组相比,脑梗死组TNF-α阳性细胞在各时间段均增加,术后48h、72hBRF组低于同期的生理盐水组(P<0.05)。结论BRF通过减轻脑水肿,降低脑内肿瘤坏死因子-α的表达,对大鼠缺血脑组织产生保护作用。

Objective To investigate the effects of Bio-wave regulation factor (BRF) on tumor necrosis factor-α(TNF-α) expression in rats after middle cerebral artery occlusion (MCAO).Methods A total of 90 adult male Sprague-Dawley rats were randomly divided into sham operation group, normal saline group and BRF treatment group. Each group consisted of five subgroups (6h, 24h, 48h, 72h and 7d), according to different time points post-ischemia. Rats in BRF treatment group and normal saline group were subjected to MCAO and administrated intraperitoneally with 1.25% BRF solution (1ml/100g) and normal saline (1ml/100g) respectively sixty minutes after operation, then once a day till they were sacrif iced. Four different methods were used for assessing neurological deficit score (NDS) , the wet-dry method for measuring brain water content, hematoxylin and eosin(HE) staining technique for observing histopathological changes, immunohistochemistry method for detecting TNF-α expression.Results 1. Behavioral evaluation: the behavioral outcomes were most serious at 48h, 72h and back to normal at 7d after MCAO. The NDS was lower in BRF treatment group than that of normal saline group at 48h. 2. Brain water content: Brain water contents both in normal saline group and BRF treatment group increased obviously at any points. Compared with normal saline group, brain edema in BRF treatment group was attenuated apparently, especially at 48h (P<0.05). 3. HE staining: histopathologic damages were alleviated with BRF administration, the inflammatory cell infiltration increased at 6h, peaked at 48h, and continued to 7d. 4. The expression of TNF-α: compared with normal saline group, the expression of TNF-α in BRF treatment group attenuated obviously at 48h and 72h (P<0.05).Conclusion The results suggest that BRF may produce neuroprotective effects against infarction damage by reducing brain edema and inhibiting the expression of TNF-α.