局部亚低温治疗胆红素脑病仔兔脑组织的病理变化

Pathologic Changes of Brain in Newborn Rabbits with Bilirubin Encephalopathy Treated by Local Mild Hypothermia

目的:观察胆红素脑病仔兔在贴敷式局部亚低温不同时间窗内脑组织的病理变化。方法:56只出生2～5d的新西兰仔兔腹腔注射胆红素200μg/g,成功建立胆红素脑病模型,随机分为A、B2组各28只,A组仔兔造模后即给贴敷式局部亚低温治疗,B组不予处理。在造模后0、6、12及24h各点2组分别取7只用光学显微镜观察脑组织病理变化和检测脑组织胆红素的浓度。结果:B组造模6h点可见神经元体积增大,肿胀,核略偏位,细胞核变化不明显;12h时神经元体积明显缩小,略呈三角形,细胞核浓缩,核形不规则;24h神经细胞数量明显减少,空泡出现。A组12及24h点神经元形态结构异常改变和胆红素浓度均显著低于B组(P<0.01)。结论:贴敷式局部亚低温可明显减轻胆红素脑病脑组织的病理变化,对脑组织具有治疗及保护作用。

Objective：To evaluate the effects of local mild hypothermia in different time windows on the pathologic changes of brain in newborn rabbits with bilirubin encephalopathy.Methods：Fifty-six newborn New Zealand rabbits（2-5 days postnatal）were injected with bilirubin intraperitoneally（200 μg/g）to establish the model of bilirubin encephalopathy.The rabbits were divided randomly into the group A（n=28）and group B（n=28）.The animals in group A received local mild hypothermia treatment after modeling,and those in group B received no treatment.The pathologic changes in brain tissue were observed under a light microscope and bilirubin levels of newborn rabbits were determined at 0,6,12 and 24 h after modeling.Results：The animals with established bilirubin encephalopathy showed significantly pathologic changes.The abnormality of neuronal morphology and levels of bilirubin were significantly decreased in group A as compared with group B at 12 and 24 h（P0.01）.Conclusion：The local mild hypothermia has protective and therapeutic effects on brain tissue and it could significantly alleviate the pathologic changes of brain in newborn rabbits with bilirubin encephalopathy.