Aston-Jones G, Segal M, Bloom F E
Brain Res. 1980 Aug 11;195(1):215-22. doi: 10.1016/0006-8993(80)90880-x.
Impulses in rat locus coeruleus neurons exhibit pronounced conduction latency decreases, followed by even larger latency increases (of over 20 msec in some cases) during a single train of antidromic activation. The magnitude of latency fluctuation varies as a function of basal antidromic latency, frequency of stimulation, and number of stimuli in a train. These and additional data indicate that this variability in latency is a consequence of altered impulse conduction velocity along the axons, perhaps reflecting reduced ion concentration gradients resulting from impulse propagation. These latency changes may allow thin unmyelinated axons to influence target cells most effectively with short bursts of activity, and suggest that myelination and large axon diameter provide for high fidelity as well as for high velocity of impulse flow in nervous tissue.
在单次逆向激活序列中，大鼠蓝斑核神经元的冲动表现出传导潜伏期显著缩短，随后甚至出现更大幅度的潜伏期增加（某些情况下超过20毫秒）。潜伏期波动的幅度随基础逆向潜伏期、刺激频率以及序列中的刺激次数而变化。这些以及其他数据表明，潜伏期的这种变异性是轴突上冲动传导速度改变的结果，可能反映了冲动传播导致的离子浓度梯度降低。这些潜伏期变化可能使细的无髓鞘轴突能够通过短时间的活动爆发最有效地影响靶细胞，并表明髓鞘形成和大的轴突直径为神经组织中冲动流动的高保真度以及高速度提供了条件。
