摘要： 目的 观察微小RNA（miRNA）-29a在小鼠神经系统内的表达特征。方法 实时定量聚合酶链反应检测经原代培养第3、7、15、21 天星形胶质细胞、神经元和出生后相应时间点小鼠大脑皮质miRNA-29a 表达变化。结果 随着小鼠生长发育，miRNA-29a 在神经系统内的表达逐渐增强，与体外原代培养第3 天相比，第7、15、21 天时神经元和星形胶质细胞miRNA-29a 相对表达量均升高（P < 0.05 或P < 0.01）；与饲养第3 天小鼠相比，饲养第7、15、21 天小鼠大脑皮质miRNA-29a 相对表达量亦升高（P <0.05 或P < 0.01）；同一观察时间点星形胶质细胞miRNA-29a 相对表达量是神经元的20 ~ 40 倍（P = 0.000），而大脑皮质miRNA-29a 相对表达量仅为星形胶质细胞的1/3（P = 0.000）。结论 miRNA-29a 在小鼠大脑皮质发育过程中呈现的高丰度特异性表达，主要表现为星形胶质细胞miRNA-29a表达上调。

关键词: 微RNAs, 星形细胞, 神经元, 大脑皮质, 聚合酶链反应, 细胞, 培养的

Abstract: Objective  To investigate the expression profile of microRNA (miRNA)-29a in mice neural cells.  Methods  Quantitative real-time polymerase chain reaction (qRT-PCR) was used to analyze miRNA-29a expression changes of neurons and astrocytes after 3, 7, 15, 21 d of primary culture in vitro, and cortex tissue of 3, 7, 15, 21 d old mice.  Results  miRNA-29a expression increased in nervous system with the growth of mice. Compared with the 3th day, miRNA-29a relative expression on the 7th, 15th, 21th days in neurons, astrocytes and cortex tissue were obviously higher (P < 0.05 or P < 0.01). At each time point, the relative expression levels of miRNA-29a in cultured astrocytes were 20-40 times higher than in cultured neurons (P = 0.000), and levels in cortex tissue were about 1/3 that seen in cultured astrocytes (P = 0.000).  Conclusions  With the growth and development of brain cortex of mice, miRNA-29a is highly expressed in astrocytes, reflecting its abundant and specific expression.

Key words: MicroRNAs, Astrocytes, Neurons, Cerebral cortex, Polymerase chain reaction, Cells, cultured