Rajakumar N, Elisevich K, Flumerfelt B A
Department of Anatomy, University of Western Ontario, London, Canada.
Brain Res. 1993 Apr 2;607(1-2):47-53. doi: 10.1016/0006-8993(93)91488-e.
A powerful and versatile axonal tracing method using biotinylated dextran, a novel analogue of biotin, is described. Pressure injection of varying volumes of 5% biotinylated dextran into various parts of the brain and spinal cord resulted in Golgi-like retrograde labeling and PHA-L-like anterograde labeling. The tracer filled the finest processes, revealing terminal axonal ramifications, distal dendrites and dendritic spines and excrescences. Extensive anterograde and retrograde labeling occurred in all pathways studied and in animals of all ages. Labeling appeared as early as 48 h and remained unchanged up to 14 days following injection. Biotinylated dextran can be detected easily with any avidin-conjugated marker for light and electron microscopic study. The resultant labeling can be combined readily with other morphological methods, such as tract tracing and/or immunocytochemical demonstration of endogenous substances. Biotinylated dextran is thus an efficient anterograde and retrograde tracer that can be combined with other neuroanatomical techniques to study details of synaptic interaction at all levels of dendritic organization.
本文描述了一种使用生物素化葡聚糖（一种新型生物素类似物）的强大且通用的轴突追踪方法。将不同体积的5%生物素化葡聚糖压力注射到脑和脊髓的各个部位，可产生类似高尔基染色的逆行标记和类似PHA-L的顺行标记。示踪剂填充了最细微的突起，显示出轴突终末分支、远端树突、树突棘和赘生物。在所研究的所有通路以及所有年龄段的动物中均出现了广泛的顺行和逆行标记。注射后最早48小时出现标记，直至14天保持不变。生物素化葡聚糖可使用任何抗生物素蛋白偶联标记物轻松检测，用于光学显微镜和电子显微镜研究。所得标记可轻松与其他形态学方法相结合，如束路追踪和/或内源性物质的免疫细胞化学显示。因此，生物素化葡聚糖是一种高效的顺行和逆行示踪剂，可与其他神经解剖学技术相结合，以研究树突组织各个层面的突触相互作用细节。
