犬颅脑枪弹伤后血脑屏障的改变及意义

目的　探讨犬脑枪弹伤后血脑屏障 (BBB)通透性改变及意义。方法　杂种犬 12只 ,随机分成正常对照、脑贯通伤 (PCI)15min、1h、6h组 (n=3) ,采用德国小口径步枪 (子弹型号 5 5 6mm ,弹头质量 2 5 7g)按上述分组要求致伤。硝酸镧心内灌注法固定犬脑 ,透射电镜下观察BBB改变。结果　犬脑枪弹伤后 15min、1h组均出现BBB改变 ,紧密连接开放 ,血管基膜外以至组织间隙内存在硝酸镧颗粒 ,后者更明显 ;至 6h组BBB改变愈加严重 ,可见大量硝酸镧颗粒经BBB进入组织间隙 ,与 15min、1h组比较差异有统计学意义 (P <0 0 5 )。结论　BBB的开放是造成颅脑火器伤后早期脑水肿的原因之一。

Change in blood-brain barrier permeability after craniocerebral gunshot injury in dog

Objective To study the change in blood-brain barrier (BBB) permeability in dog with craniocerebral gunshot injury and its significance. Methods Twelve dogs were randomly divided into control group, 15min ofter penetrating craniocerebral injury (PCI) group, 1h after PCI group and 6h after PCI group (n=3). The injury was produced by a small-calibre rifle made in Germany (type 5.56mm, weight of bullet 2.57g). Lanthanum nitrate was infused through the heart. The changes in BBB permeability were observed under electronic microscope. Results In 15min PCI group and 1h PCI group, changes in BBB permeability was observed, with manifestation of opening of tight junctions, with lanthanum nitrate particles passing through BBB into the brain tissues. These changes were more marked in 1h PCI group. Comparing with the above two groups, even more lanthanum nitrate particles were found in the brain tissue in the 6h group (P<0.05). Conclusion Impairment of BBB function is one of the reasons for early occurrence of brain edema after craniocerebral gunshot injury.