实验性脑挫伤后 Fos蛋白和 NGFR变化与损伤时间关系的研究

目的 检测分析不同损伤时间组实验大鼠脑挫伤灶周围神经细胞中 NGFR阳性染色强度变化与损伤后经过时间之间的关系,对其在脑挫伤时间推断中的作用作出评价。方法 运用免疫组织化学技术（ SABC法）,结合计算机彩色图像分析技术观察大鼠实验性脑挫伤后原癌基因 c－ fos的表达产物 Fos蛋白和神经生长因子受体（ NGFR）的染色变化。结果 （ 1）伤后 0.5h组在挫伤灶周围可见 Fos阳性染色细胞出现。伤后 3h组阳性表达数量和强度达峰值,且分布广泛。后表达逐渐降低。 1d后各组未见 Fos阳性染色强度增加的细胞。对照组染色为阴性。（ 2）伤后 1d组在挫伤灶周围可见少量 NGFR阳性染色细胞,以神经细胞表达为主。伤后 3d组,阳性细胞表达与 1d组相比有显著性增强 (P< 0.01), 数 量 和 着 色 强 度 达 到 高 峰 , 量 多 且 染 色 深 。 之 后 逐 渐 缓 慢 减 弱 。 对 照 组 染 色 为 阴 性 。 可 见 脑 挫 伤 后 Fos和 NGFR在 损 伤 局 部 的 阳 性 染 色 分 别 在 伤 后 早 期 及 随 后 较 晚 时 段 里 出 现 。 前 者 表 达 时 间 短 暂 , 而 后 者 则 持 续 时 间 较 长 , 但 都 有 一 定 的 规 律 性 。 结 论 Fos蛋 白 和 NGFR变 化 可 用 于 脑 挫 伤 后 不 同 时 段 的 损 伤 时 间 推 断 。

A study of the relation between interval of the injury and the reaction of neurons,glial cells after experimental brain contusion

OBJECTIVE: To observe the change of c-fos protein(Fos) and nerve growth factor receptor (NGFR) staining in the brain of rat after experimental brain contusion. METHODS: Immunohistochemistry of c-fos and NGFR were applied to investigate the brain contusion. RESULTS: (1) The expression of Fos protein could be observed at 0.5 h after injury and then increased with the prolonging of time. By 3 h after injury, the positive staining cells could be detected massively not only in and round the wound site but also in other areas of the whole ipsilateral cortex. The stains decreased 6-12 h later and could hardly be detected 1 d after the brain contusion. The control-experiment is negative. (2) NGFR positive staining cells could be found round the wound area 1 d postlesion. At 3 d following injury, a peak of massive positively stained cells appeared both in number and in intensity, showing significant differences compare with that of 1 d after damage (P < 0.01). 5 d later the positive express declined slowly. The express in the control-rat is negative. CONCLUSION: There is a rule that the expression of Fos and NGFR positive staining changes with time going after brain contusion, which will be of great value in estimation of brain injury time. Detection of Fos can be used for time deduction in earlier period after injury, while NGFR in later period. They are also very important for distinguishing between antemortem or postmortem injury.