核黄疸模型大鼠脑细胞损伤及行为学后遗症的研究

摘要

Objective To study the brain cell injuries and behavioral changes of newborn rats with kernicterus. Methods Twenty-five 5-day-old Sprague-Dawley rats were divided into control group (n=11) and model group (n=14) radomly. The model group was injected with bilirubin solution 10μg/g in the cisterna magna, while the control group was injected with equal volume of normal saline. The neurobe-havioral changes were observed and the body mass were recorded. TUNEL staining was used to check the apoptosis of striatal nerve cells of basal ganglia in the model group (n=3) on the first day after modeling. The remaining rats were assessed by gait analysis and beam-walking test 19 days after birth, and Morris water maze test was performed 30 days after birth. Results The model group showed apparently abnor-mal neurobehavioral changes, such as clenched fists, opisthotonos and the body mass were significantly lower in the model group than in the control group (F>27.707, P<0.001). TUNEL staining showed striatal nerve cells apoptosis in the model group. For the gait analysis, the step lengths of both hind legs were shorter (t>4.129, P<0.01), and the difference of step length was longer (t=-4.415, P<0.001) in the model group than in the control group, however, there was no significantly difference in the step width between two groups (t=0.462, P=0.649). For the beam-walking test, the score was lower in the model group than in the control group (t=-3.644, P=0.004). For the Morris water maze test, the escape latency was longer (F>6.206, P<0.05), and the number of crossing platform was less (t=3.297, P=0.004) in the model group than in the control group. Conclusion The newborn rats' model of kernicterus showed deficits in multiple motor functions and learn-ing and memory ability, which could be assessed by gait analysis, beam-walk test and Morris water maze test, respectively.%目的：探讨核黄疸模型大鼠脑细胞损伤及行为学改变情况。方法25只5日龄Sprague-Dawley大鼠随机分为对照组(n=11)和模型组(n=14)。模型组予小脑延髓池内注射胆红素溶液10μg/g，对照组注射等量生理盐水。观察注射后大鼠的神经行为变化，并记录其体质量；建模后第1天予TUNEL法观察模型组(n=3)脑基底节纹状体神经细胞凋亡情况；余下大鼠均在生后19 d行步态分析及横木行走测试，30 d行水迷宫实验。结果模型组出现明显神经行为异常，如握拳、角弓反张，且体质量显著低于对照组(F>27.707, P<0.001)。TUNEL染色示模型组基底节纹状体神经细胞凋亡。步态分析中，模型组左右后肢步长均短于对照组(t>4.129, P<0.01)，步长差值显著大于对照组(t=-4.415, P<0.001)，但步宽与对照组无显著性差异(t=0.462, P=0.649)。横木行走测试中，模型组得分明显低于对照组(t=-3.644, P=0.004)。Morris水迷宫实验中，模型组各时间点逃避潜伏期均长于对照组(F>6.206, P<0.05)；穿越平台次数少于对照组(t=3.297, P=0.004)。结论核黄疸模型大鼠具有多项运动功能异常和学习记忆障碍，可分别使用步态分析、横木行走测试及水迷宫实验进行评价。