Rhythmicity in single fiber postganglionic activity supplying the rat tail
Rhythmicity in single fiber postganglionic activity supplying the rat tail
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DOI：
10.1152/jn.1999.81.5.2026
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发表时间：
1999-05-01
影响因子：
2.5
通讯作者：
Jänig, W
中科院分区：
文献类型：
--
作者：
Häbler, HJ;Bartsch, T;Jänig, W
持续交感缩血管活性的时间模式可能在神经血管传递中起重要作用。在这里，我们分析了活动的节后纤维投射到腹侧收集神经的麻醉和人工通气vagotomized Wistar大鼠在normocapnic条件下的节律性放电的存在。大多数研究的纤维可能是血管收缩和参与体温调节。与心电图同步产生交感神经活动的累积直方图以检测心律，与膈神经活动同步产生交感神经活动的累积直方图以检测与中枢呼吸周期的调制，并且与气管压力同步产生交感神经活动的累积直方图以揭示与人工通气相关的反射调制。交感神经活动，膈神经活动和气管压力也进行了检查，频谱分析和自相关检测节奏不同于呼吸。分析了27根含有2至7根具有自发活动的纤维和51根单纤维的细丝。持续活动为1.12 ± 0.65 imp/s（平均值± SD，n = 51）;传导速度为0.62 ± 0.06 m/s（n = 30）。交感神经活动的心律性较弱（46.2 ± 16.4%）。19/27例少纤维标本和37/51例单纤维标本的主节律与中枢呼吸周期一致。该模式由吸气时的抑制和呼气时的激活组成。在该组的10/19个少纤维制剂和21/37个单纤维制剂中，也存在与人工通气相关的伴随的不太显著的节律。相比之下，8/27少纤维制剂和11/51单纤维表现出占主导地位的泵相关的调制，而膈相关的节律是从属的。两条单纤维活动的主导节律与中枢呼吸和人工通气均无关。我们的结论是，大多数节后神经元供应的大鼠尾巴正在进行的活动调制的中央呼吸节律发生器，这表明呼吸驱动的变化可能会改变灌注的尾巴，因此散热。与人工通气并行的反射调制，独立于迷走神经传入，可能是由于压力感受器活动的抑制性变化，也是这些神经元节律性的重要来源。
The temporal pattern of ongoing sympathetic vasoconstrictor activity may play an important role for neurovascular transmission. Here we analyzed the activity of postganglionic fibers projecting into the ventral collector nerve of anesthetized and artificially ventilated vagotomized Wistar rats with respect to the presence of rhythmic firing under normocapnic conditions. Most of the fibers studied were likely vasoconstrictor and involved in thermoregulation. Accumulate histograms of sympathetic activity were produced synchronized with the,electrocardiogram to detect cardiac rhythmicity, with phrenic nerve activity to detect modulation with the central respiratory cycle, and with tracheal pressure to uncover a reflex modulation associated with artificial ventilation. Sympathetic activity, phrenic activity, and tracheal pressure also were examined by spectral analysis and autocorrelation to detect rhythmicities distinct from respiration. Twenty-seven filaments containing two to seven fibers with spontaneous activity and 51 single fibers were analyzed. Ongoing activity was 1.12 0.65 imp/s (mean +/- SD, n = 51); conduction velocity was 0.62 +/- 0.06 m/s (n = 30). Cardiac rhythmicity in sympathetic activity was weak (46.2 +/- 16.4%). The dominant rhythm in the activity of 19/27 few-fiber preparations and 37/51 single fibers corresponded to the central respiratory cycle. The pattern consisted of an inhibition during inspiration and an activation in expiration. In 10/19 few-fiber preparations and 21/37 single fibers of this group, there was also a concomitant, less prominent rhythm related to artificial ventilation. By contrast, 8/27 few-fiber preparations and 11/51 single fibers exhibited a dominant pump-related modulation, whereas phrenic-related rhythmicity was subordinate. The dominant rhythm in the activity of two single fibers was related to neither central respiration nor artificial ventilation. We conclude that the ongoing activity of most postganglionic neurons supplying the rat tail is modulated by the central respiratory rhythm generator, suggesting that changes in respiratory drive may alter perfusion of the tail and therefore heat dissipation. Reflex modulation in parallel with artificial ventilation, independent of vagal afferents and possibly due to ventilatory changes of baroreceptor activity, is also an important source of rhythmicity in these neurons.