碱性成纤维细胞生长因子对受照后大鼠血脑屏障的影响

Quantitative analysis of the effect of basic fibroblast growth factor on radiation induced blood brain barrier disruption

目的评价定量检测放射性血脑屏障（BBB）破坏的不同方法，探讨碱性成纤维细胞生长因子（bFGF）对放射性BBB破坏的保护作用。方法60只急性放射性脑损伤模型大鼠（直线加速器6MeV电子束单次照射25Gy）分为单纯照射组和照射前尾静脉注射bFGF组（250ng／kg），并设未照射对照组；分别于照射后2、7和30d采用脑干-湿重法检测脑含水量，并用单次静脉注射3mg／kg伊文氏蓝（EB）后脑组织的EB含量法评估BBB破坏情况。结果照射后脑组织含水量和EB含量均较对照组明显增高，注射bFGF组脑组织含水量和EB含量均低于单纯照射组（P〈0．05）。受照后不同日期的脑组织EB含量差异有统计学意义（P〈0．05），而脑含水量差异没有统计学意义。结论注射EB后检测脑组织，浓度法较干湿重法测脑含水量能更好地反映BBB的破坏情况；bFGF对受照后BBB破坏有保护作用。

Objective To evaluate the different detection methods of blood brain barrier （BBB） disruption, and to explore the protection effect of basic fibroblast growth factor（bFGF） on the BBB disruption. Methods 60 rats were classified into radiation group, bFGF intravenous injection group and contol group. The water content of brain was measured by wet-dry weight formula and Evans blue（EB） concentration was detected after intravenous injection（3 mg/kg） after 2,7 and 30 days post irradiation in each group. The data were collected and analysed to evaluate the degree of BBB disruption. Results Both of EB concentration and water content in brain increased after irradiation, which were lower in bFGF injection group than those in radiation group （ P 〈 0.05）. Statistic difference （ P 〈 0.05） was found at different days following exposure for EB concentration but not for water content in brain. Conclusions It＇s more effective of EB concentration to represent the BBB disruption than of water content. Intravenous injection of bFGF may have some protective effects on BBB disruption induced by radiation.