Madison R, Davis J N
Exp Neurol. 1983 Apr;80(1):167-77. doi: 10.1016/0014-4886(83)90013-4.
The neuronal sprouting of noradrenergic fibers was studied in the hippocampal formation. The extent and time course of lesion-induced plasticity of both central and peripheral noradrenergic neurons was determined by assaying norepinephrine (NE) concentrations and high-affinity [3H]NE uptake in the dentate gyrus at 2 to 16 weeks after medial septal lesions. Two weeks after a medial septal lesion there was a dramatic decrease in dentate NE. During the subsequent weeks normal concentrations of dentate NE were reestablished. The recovery or increase of NE with time reflected a contribution from both central and peripheral noradrenergic systems. Although both central and peripheral noradrenergic systems contributed to this recovery, they did so in very different ways. The time course of the central noradrenergic response was slower than that of the peripheral system and the final NE concentrations were quite different for the two systems. The central adrenergic system's sprouting response apparently stabilized when normal NE concentrations were attained, whereas the ingrowth of peripheral sympathetic fibers continued to concentrations that were well above normal unoperated levels. The findings have implications in relationship to the different possible controlling mechanisms governing neuronal plasticity of the central and peripheral noradrenergic systems.
研究了海马结构中去甲肾上腺素能纤维的神经元发芽情况。通过在中隔损伤后2至16周测定齿状回中去甲肾上腺素（NE）浓度和高亲和力[3H]NE摄取量，确定了中枢和外周去甲肾上腺素能神经元损伤诱导可塑性的程度和时间进程。中隔损伤后两周，齿状回NE显著降低。在随后的几周内，齿状回NE浓度恢复正常。NE随时间的恢复或增加反映了中枢和外周去甲肾上腺素能系统的共同作用。虽然中枢和外周去甲肾上腺素能系统都促成了这种恢复，但方式截然不同。中枢去甲肾上腺素能反应的时间进程比外周系统慢，且两个系统最终的NE浓度差异很大。当达到正常NE浓度时，中枢肾上腺素能系统的发芽反应显然稳定下来，而外周交感神经纤维的长入持续到远高于正常未手术水平的浓度。这些发现对于控制中枢和外周去甲肾上腺素能系统神经元可塑性的不同可能机制具有启示意义。
