Spastin促进海马神经元树突野的形成

目的　探讨微管切割蛋白Spastin对海马神经元树突野形成的作用。 方法　把目的基因转染入原代海马神经元，用免疫荧光显示树突α-氨基-3-羟基-5-甲基-4-异恶唑丙酸（AMPA）受体，全细胞膜片钳检测微小兴奋性突触后电流（mEPSCs）。 结果　过表达Spastin促进树突生长以及分支形成，敲减Spastin抑制树突的生长和新的分支形成，与对照细胞差异有统计学意义（P<0.05）；Sholl分析结果显示Spastin提高树突野的复杂性（P<0.05）；免疫荧光结果显示，过表达Spastin促进AMPA受体GluA2亚基在树突的表达，与对照组差异有统计学意义（P<0.05）；而敲减Spastin则抑制树突GluA2的表达（P<0.05）；全细胞膜片钳检测显示，过表达Spastin神经元的mEPSCs振幅和频率均增加，敲减Spastin则使mEPSC的幅度和频率降低（P<0.05）。 结论　Spastin促进神经元树突野的形成，而且形成的树突是功能性树突。

Spastin promotes the formation of dendritic field in hippocampal neurons

Objective To investigate the effect of microtubule-severing protein Spastin on the formation of dendritic field in hippocampal neurons.Methods Spastin was transfected into hippocampal neurons and theα-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid(AMPA)receptors on dendrites were detected by immunofluorescence.Whole-cell patch clamp was used to detect miniature excitatory postsynaptic currents(mEPSCs).Results Overexpression of Spastin promoted dendritic outgrowth and branch formation,while knockdown of Spastin inhibited dendritic outgrowth and formation of new branches.The results showed that Spastin significantly promoted the formation of and complexity of dendritic field compared with the control group(P<0.05).Sholl analysis results showed that Spastin increased the complexity of dendrites(P<0.05).Immunofluorescence results showed that overexpression of Spastin promoted the expression of AMPA receptor GluA2 subunit in dendrites,which was significantly different from the control group(P<0.05),while knockdown of Spastin inhibited the expression of GluA2 in dendrites(P<0.05).Whole-cell patch clamp detection showed that overexpression of Spastin increased the amplitude and frequency of m EPSCs,however,knockdown of Spastin significantly decreased the amplitude and frequency of mEPSC(P<0.05).Conclusions Spastin promotes the formation of neuronal dendrites that are the functional dendrites.