CPG15在大鼠脑弥漫性轴索损伤中的表达及意义

目的探讨大鼠脑弥漫性轴索损伤（diffuse axonal injury，DAI）中不同时间点脑额叶皮层组织中候选可塑性相关基因15（candidate plasticity related gene 15，CPG15）的表达及意义。方法雄性SD大鼠54只，随机分为正常对照组18只和DAI组36只；采用头颅侧向旋转致伤方法制作DAI模型，并按伤后大鼠处死时间分为第1d、4d、7d、10d、14d、21d组，每组6只。用免疫组化方法检测大鼠脑额叶皮层CPG15的表达，并分析其表达变化特点。CPG阳性结果判断标准以细胞浆内出现棕黄染色颗粒为阳性，反之为阴性。结果正常对照大鼠额叶皮质中无CPG15的表达；DAI后，CPG15表达于神经元细胞的胞浆内。DAI后1d，大鼠大脑皮层仅见少量CPG15表达；DAI后4d、7d、10dCPG15表达逐渐增强，至14d达到峰值；损伤后第21d仍维持在较高水平。DAI后不同时间，神经元数量逐渐增多。结论DAI后，随着脑内CPG15表达增强，神经元数量也逐渐增多，提示二者存在正相关；本文对有关机理进行了讨论。

The expression and significance of CPG15 in rat model of diffuse axonal injury

Objective To investigate the expression and significance of CPGl5 (candidate plasticity related gene 15) in frontal brain cortex of rat model of diffuse axonal injury (DAI) at different posttraumatic time point. Methods The 54 male SD rats were divided randomly into normal control group (n=18) and DAI group (n=36). The DAI group was subdivided into 1d、4d、7d、10d、14d、21d group with 6 in each. The DAI model was produced by lateral head rotation device. The expression of CPGl5 in the frontal cortex in rat brain was investigated by immnohistochemical method and its change was also analyzed. The occurrence of yellow-brown particles was considered as "positive", and lack of the stain as "negative". Results No expression was found in the frontal cortex in normal rat brain. The expression of CPGl5 existed in small amount in the frontal brain cortex in the rat 1 day post DAI, and at this time the number of neurons was significantly decreased. The expression became stronger gradually at 4,7 and 10 day, and reahed to the peak at 14 day. It maintained at higher level until 21 day post DAI. Meanwhile, the neurons increased in number with the time internal post DAI. Conclusion The expression of CPI15 and the number of neurons were much associated positively with each other post DAI. The underlying mechanism and significance were discussed.