摘要
目的 研究体外培养神经元机械损伤后不同亚型Homer蛋白表达的变化规律,进一步阐明Homer与神经元损伤的关系。方法 胎鼠脑皮质神经元体外培养7d,以微量移液器塑料滴头划割培养的神经元,横、竖各划8道,划伤宽度约1mm,造成机械性损伤。在伤后不同时间(10、30min,1、3、6、12、24、72h),采用链酶亲合素过氧化物酶复合物法(SABC法)行免疫组化染色。对照组不进行机械性划割,其它处理同损伤组。结果 对照组神经元在各时间点Homer1a免疫组化染色呈弱阳性。机械性损伤后从伤后10min持续至24hHomer1a表达量增加,免疫组化染色呈阳性。阳性染色呈颗粒状分布于胞浆、胞膜及突起。Homer1b/c,Homer2a/b和Homer3在对照组神经元中即有一定程度表达,机械性损伤后,其表达量无明显变化。结论 神经元机械性损伤后Homer1a表达明显升高,而Homer1b/c、2a/b和3表达无明显变化。Homer1a对第1组代谢型谷氨酸受体(mGluR)的功能具有负反馈作用,Homer1b/c、2a/b和3则调节mGluR在细胞表面的分布,提高其稳定性。据此推测,增加Homer1a表达或减少Homer1b/c、2a/b和3的表达可能改变mGluR受体信号的传递效率,对神经元具有保护作用。
Objective To study the expression and significance of Homer in mechanically injured cortical neuron in vitro in order to elucidate the relationship between Homer and neuronal injury.Methods The mouse fetus cortical neurons were divided into injury and control groups after 7 days in vitro cultivation. Mechanical injury was performed by plastic tip on cortical neuronal culture in injury group. Then immunohistochemical examination was made on these neurons at different times after injury (10 min, 30 min,1, 3, 6, 12, 24, 72 h). The control group underwent all the same management except for the tip-caused mechanical injury.Results There were widespread expressions of Homer 1a positive neurons in injury group from 10 min to 24 h after injury. The positive particles were found in the neuronal cytoplasm, cyto-membrane and dendrites. While in control group, there were only weak expressions of Homer 1a in neurons. Homer 1b/c, Homer 2a/b and Homer 3 were obviously expressed in neurons of control groups, but did not increase significantly after mechanical injury. Conclusion Because Homer modulates the distribution and function of metabotropic glutamate receptor (mGluR), increasing the expression of Homer 1a or decreasing that of Homer 1b/c, Homer 2a/b and Homer 3 may change the efficacy of signal transduction of mGluR, which protects neurons from secondary insults.
出处
《中华神经外科疾病研究杂志》
CAS
2005年第2期133-136,共4页
Chinese Journal of Neurosurgical Disease Research
基金
国家自然科学基金资助项目 (30270534 )
高等学校骨干教师资助项目
