甘露醇诱导大鼠血脑屏障开放的影响因素分析

Analysis of factors influencing mannitol to induce blood-brain-barrier opening

目的 :研究动脉内输入甘露醇诱导血脑屏障(blood brainbarrier ,BBB)开放的影响因素。方法 :经大鼠颈外动脉插管将不同浓度甘露醇 (2 0 %和 2 5% )以不同速度和不同时间用微量输液泵输入大鼠的颈内动脉 ,考察在输入 2 5 %甘露醇后不同保留时间 (0、2、4、6、8min)注入伊文思蓝时显示的BBB开放最佳时间点 ;考察输入甘露醇的浓度、输入速度和时间变化对甘露醇诱导BBB开放的影响 ;并按性别和体重分别统计死亡率 ,观察性别和体重对大鼠输入甘露醇耐受性的影响。结果 :以 0 .12ml·s-1,30s输入 2 5 %甘露醇 3.6ml后 2min时BBB开放程度最好 ,2 0 %甘露醇几乎无开放BBB的作用 ,输入2 5 %甘露醇的速度减慢或输入时间缩短将降低BBB的开放程度。体重影响大鼠对甘露醇的耐受性 ,体重较大时耐受性较高。结论 :影响甘露醇诱导BBB开放的因素有 :甘露醇的浓度、输入甘露醇的速度和时间及输入甘露醇后的保留时间。

AIM: To study factors influencing mannitol to induce blood brain barrier (BBB) opening. METHODS: By constant flow pump, mannitol with different concentration (20% and 25%) was infused into left internal carotid artery of adult Wistar rats via their left external carotid artery at different speed and time. Firstly, after mannitol with a concentration of 25% was transfused, the optimal open time of BBB was investigated using Evans blue as an indicator by injection at different time (0, 2, 4, 6, and 8 min). Then influences of concentration of mannitol, speed of infusion, and change of time on mannitol to induce BBB opening were studied. Finally, death rate was counted according to sex and body weight in order to observe the influence of sex and body weight on tolerance of rats. RESULTS: The open degree of BBB was optimal after 2 min when 3.6 ml mannitol with a concentration of 25% was infused in 30 s at a speed of 0.12 ml·s -1 . However, mannitol with a concentration of 20 % did not almost have any effect on opening of BBB. Slowing of infusion speed or shortening of infusion time of mannitol reduced opening degree of BBB. Body weight affected rat tolerance to mannitol, and the tolerance of the rat was higher in those with higher weight. CONCLUSION: The factors influencing mannitol to induce BBB opening are as follows: concentration, infusion speed, and keeping time of mannitol. And the tolerance to mannitol is not concerned with the sex of the rats, but the body weight of the rats.