免疫荧光电镜技术观察ChAT在脊髓前角运动神经元中超微结构水平上的分布

胆碱乙酰转移酶（choline acetyltransferase, CHAT）是催化乙酰胆碱（acetylcholine，Ach）合成的特异性酶，是监测中枢和周围神经系统中胆碱能神经元功能状态的最特异性指标。本实验应用激光扫描公共聚焦显微镜、免疫荧光纳米金标记技术和包埋前免疫标记电镜技术，观察ChAT在脊髓前角运动神经元中超微结构水平上的分布。包埋前免疫标记降低了电镜制样对抗原性的破坏；激光扫描共聚焦显微镜荧光图像为透射电镜超薄切片提供了精确定位支持，有利于选择免疫标记效果更好的细胞进行超薄切片；振动切片有利于结构及抗原的保存使纳米金颗粒更易渗透入细胞，提高了免疫标记阳性率。

Observation on ultrastructurai level distribution of ChAT in anterior horn motor neuron of spinal cord

Choline acetyltransferase （CHAT） is a specific enzyme synthesised with acetylcholine （Ach） and the most specific indicator to monitor functional status of cholinergic neurons in the central and peripheral nervous system. In this study, we observed the subcellular distribution of ChAT in the anterior horn motor neurons of spinal cord by laser scanning confocal microscopy, immunofluorescence nanogold labeling technique, and pre-embedding immunolabeling electron microscopic technique. The pre-embedding immu- nolabeling reduced the destruction of antigenicity of ChAT in the process of sample preparation. Fluorescence image of eonfocal microscopy provided precise location of ChaT for selecting cells to be sliced to ultrathin section. Vibration slicing was beneficial to the preservation of antigen and ChAT structure, so the nanogold particles could more easily penetrate into cells.