两种不同开放血脑屏障方法的比较

目的 比较超声波诱导微泡破坏和甘露醇渗透性开放两种方法对大鼠血脑屏障通透性的影响.方法 大鼠分为2个实验组和1个对照组,1个实验组大鼠经股静脉注入微泡造影剂后,采用频率43 kHz、声强1.2 W/cm2的超声波经大鼠颅骨照射3 min;另1个实验组大鼠经颈内动脉注入20%甘露醇.干湿重法测定脑水含量,荧光显微镜观察伊文思蓝的渗出.结果 两种方法都可以可逆开放血脑屏障,利用超声波诱导微泡破坏法开放血脑屏障较甘露醇渗透性开放法局限且持久.结论 超声波诱导微泡造影剂破坏是一种无创和具靶向性开放血脑屏障的新方法.

Permeability of blood-brain barrier by ultrasound-induced microbubble destruction or mannitol osmotic opening in rats

Objective To compare the permeability of blood-brain barrier (BBB) by 2 different opening methods, ultrasound-induced microbubble destruction and mannitol osmotic opening in rats. Methods Totally 80 Wistar rats were divided into ultrasound group (A, n=35), mannitol group (B, n=35) and saline group (C, n=10). The rats of group A were sonicated by ultrasound(43 kHz, 1.2 W/cm2)for 3 min after microbubbles injected through femoral vein, and those from group B received an injection of 20% mannitol into the internal carotid artery, those of group C got saline injection into femoral vern. Brain water content was determined by dry-wet weight method. Evans blue dye exudation in the brain was observed with fluorescence microscopy. Results Two methods opened BBB reversibly, and the effects of ultrasound-induced microbubble destruction in opening BBB were more localized and durable than mannitol osmotic opening. Conclusion Ultrasound-induced microbubble destruction is a promising method for noninvasively and targeted opening BBB.