经鼻给予酸性成纤维细胞生长因子对脑梗死大鼠的血管和神经再生作用

Angiogenesis and neurogenesis effects of by acidic fibroblast growth factor delivered intranasally in rats with cerebral infarction

目的研究经鼻给予酸性成纤维细胞生长因子(acidic fibroblast growth factor,aFGF)对脑梗死后神经和血管再生及神经功能恢复的影响。方法健康雄性SD大鼠30只,随机分为aFGF组(n=12)、对照组(n=12)和假手术组(n=6);aFGF组和对照组大鼠建立大脑中动脉闭塞模型,脑缺血再灌注24h后经鼻分别给予10μg aFGF(200μl)和等容积生理盐水,1次/d,连续7d;同时腹腔注射5-溴脱氧尿核苷(Bromode-oxyuridine,BrdU)50mg/kg,1次/d,连续13d;假手术组操作过程和给药与对照组相同,但不用线栓阻塞大脑中动脉;分别在术前和术后第1、7、14d采用改良神经功能评分评价大鼠神经功能改变情况,并于术后第14d经尾静脉注入异硫氰酸荧光素右旋糖酐(FITC-dextran),采用免疫组化及激光共聚焦方法分别检测梗死灶周、室管膜下区和纹状体BrdU阳性细胞及微血管的数量。结果术后第7及14d aFGF组神经功能评分显著低于对照组;术后第14d aFGF组缺血侧室管膜下区和纹状体BrdU阳性细胞数与对照组相比均显著增高(P<0.01),假手术组仅见少量BrdU阳性细胞;激光共聚焦显示aFGF组梗死灶周微血管数较对照组显著增加(P<0.05);同时,与对照组相比经鼻给予aFGF能增加BrdU阳性细胞在血管内皮细胞中的百分比,且有统计学意义(P<0.05)。结论经鼻给予aFGF能有效促进神经和血管再生,改善脑缺血后神经功能评分,对于治疗脑梗死具有潜在的应用前景。

Objective To investigate the effects of aFGF on angiogenesis and neurogenesis after intranasal administration. Methods Adult male Sprague-Dawley rats were randomized into aFGF（n = 12）, control （n = 12） and sham groups （n = 6）. aFGF and control groups were intranasal administrated with aFGF or saline respectively,once daily for 7 days, starting 24 hours after middle cerebral artery occlusion （MCAO）. BrdU （50 mg/kg） was intraperitoneally injected daily for 13 days. Modified neurological severity scores （mNSS） tests were performed at 0, 1,7 and 14th day after MCAO. BrdU positive cells and microvessels were detected by immunohistochemistry and three-dimensional image respectively. Results At 7^th and 14^th day after MCAO, mNSS were significantly lower in aFGF group than that in control group. Treatment with aFGF significantly increased the number of proliferated endothelial cell compared with saline treatment at 14^th day （P〈0.05）. As evaluated by three-dimensional laser scanning confocal microscopy, treatment with aFGF increased the number of the microvessel in ischemic boundary zone. Compared with control rats, the number of BrdU positive cells in subventricular zone （SVZ） and striatum were significantly increased in aFGF group（P〈0.05）. Conclusions Our data indicates intranasal administration of aFGF may enhance angiogenesis and neurogenesis in CNS, which may contribute to neurological functional recovery after cerebral infarction.