Sympathetic neural activation: an ordered affair
Sympathetic neural activation: an ordered affair
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DOI：
10.1113/jphysiol.2010.195941
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发表时间：
2010-12-01
影响因子：
5.5
通讯作者：
Shoemaker, J. Kevin
中科院分区：
文献类型：
--
作者：
Steinback, Craig D.;Salmanpour, Aryan;Shoemaker, J. Kevin
节后交感神经元的募集是否有规律可循？使用新的多单位动作电位检测和分析技术，我们试图确定应激期间交感血管运动神经元的激活是否受招募大小原则的支配。多单位节后交感神经活动(腓神经)采集自5名男性受试者在安静和交感神经应激升高期间(吸气末呼吸暂停；178+/-37 S，平均值+/-S.D.)。与基线(0.24+/-0.04 V)相比，应激期交感神经爆发量增大(1.34+/-0.38 V，P<0.05)。阵发性大小的增加与节后交感神经活动多单位阵发的动作电位数目(r=0.88+/-0.04，P<；0.001)和检测到的动作电位的幅度(r=0.88+/-0.06，P<；0.001)直接相关。较大的、原本沉默的神经元的招募约占所检测到的不同大小的动作电位增加的74%。此外，动作电位传导速度(潜伏期的倒数)随着动作电位大小的增加而增加(R2=0.936，P=0.001)。由于轴突直径与动作电位大小和传导速度呈正相关，这些数据表明基于神经元大小的有序募集原则适用于节后交感血管运动神经元。这一信息可能与我们对节后交感神经反射特异性募集策略、应激期间血管运动控制模式、交感神经元特性的可塑性以及健康和疾病中的募集的理解有关。
Is there an ordered pattern in the recruitment of postganglionic sympathetic neurones? Using new multi-unit action potential detection and analysis techniques we sought to determine whether the activation of sympathetic vasomotor neurones during stress is governed by the size principle of recruitment. Multi-unit postganglionic sympathetic activity (fibular nerve) was collected from five male subjects at rest and during periods of elevated sympathetic stress (end-inspiratory apnoeas; 178 +/- 37 s(mean +/- S.D.)). Compared to baseline (0.24 +/- 0.04 V), periods of elevated stress resulted in augmented sympathetic burst size (1.34 +/- 0.38 V, P < 0.05). Increased burst size was directly related to both the number of action potentials within a multi-unit burst of postganglionic sympathetic activity (r = 0.88 +/- 0.04, P < 0.001 in all subjects), and the amplitude of detected action potentials (r = 0.88 +/- 0.06, P < 0.001 in all subjects). The recruitment of larger, otherwise silent, neurons accounted for approximately 74% of the increase in detected action potentials across burst sizes. Further, action potential conduction velocities (inverse of latencies) were increased as a function of action potential size (R2 = 0.936, P = 0.001). As axon diameter is positively correlated with action potential size and conduction velocity, these data suggest that the principle of ordered recruitment based on neuronal size applies to postganglionic sympathetic vasomotor neurones. This information may be pertinent to our understanding of reflex-specific recruitment strategies in postganglionic sympathetic nerves, patterns of vasomotor control during stress, and the malleability of sympathetic neuronal properties and recruitment in health and disease.