Forman D S, Padjen A L, Siggins G R
Brain Res. 1977 Nov 11;136(2):197-213. doi: 10.1016/0006-8993(77)90798-3.
Rapid movements of intra-axonal organelles in acutely isolated single myelinated fibers from bullfrog sciatic nerve were visualized by dark-field microscopy. The movements were recorded by cinemicrography, and analyzed by computer-based methods. The movements are saltatory and bidirectional, but each particle moves mainly in a single direction. For more than 90% of the particles, the predominant movement direction is retrograde, i.e. toward the cell body. Quantitative measurements on a variety of parameters of the organelle movements are presented. Different particles in the same axon show a broad range of mean speeds. The average mean speed of movement in the retrograde direction at 28 degrees C was 1.08 micrometer/sec (S.D. - 0.41), equivalent to an axonal transport rate of 93 mm/day. Disperse distributions were also found for other parameters such as the instantaneous velocities of individual particles. Quantal velocities, periodic movement patterns, and specific 'channels' were not detected. When the data from a population of particles is treated statistically, the average mean speed, the distribution of velocities, and other statistical parameters are found to be similar in different axons studied at the same temperature. Direct microscopical observation of axonal organelle movement is a technique which provides information about axonal transport which is different from and complementary to that obtained from enzyme accumulation of radioactive tracer methods.
通过暗视野显微镜观察了从牛蛙坐骨神经急性分离的单根有髓纤维中轴突内细胞器的快速移动。这些移动通过电影显微镜记录，并采用基于计算机的方法进行分析。移动是跳跃式的且双向，但每个颗粒主要沿单一方向移动。超过90%的颗粒，其主要移动方向是逆行的，即朝向细胞体。给出了对细胞器移动的各种参数的定量测量。同一轴突中的不同颗粒显示出广泛的平均速度范围。在28摄氏度时逆行方向的平均移动速度为1.08微米/秒（标准差 - 0.41），相当于93毫米/天的轴突运输速率。对于其他参数，如单个颗粒的瞬时速度，也发现了分散分布。未检测到量子速度、周期性移动模式和特定的“通道”。当对一群颗粒的数据进行统计处理时，发现在相同温度下研究的不同轴突中，平均平均速度、速度分布和其他统计参数相似。轴突细胞器移动的直接显微镜观察是一种提供有关轴突运输信息的技术，该信息与从酶积累或放射性示踪方法获得的信息不同且互补。
