Renal hemodynamic effects of activation of specific renal sympathetic nerve fiber groups
Renal hemodynamic effects of activation of specific renal sympathetic nerve fiber groups
复制标题
DOI：
10.1152/ajpregu.1999.276.2.r539
复制
发表时间：
1999-02-01
影响因子：
2.8
通讯作者：
Sawin, LL
中科院分区：
文献类型：
--
作者：
DiBona, GF;Sawin, LL
为了研究激活一个独特的群体的肾交感神经纤维对肾血流（RBF）动力学的影响，麻醉大鼠与肾交感神经活动（RSNA）记录电极和电磁流量探头对同侧肾动脉。外周热感受器刺激（外部热）被用来激活一个独特的群体的肾交感神经纤维，并增加总RSNA。总RSNA反射性增加到与躯体受体刺激（尾部压缩）相同的程度。两种刺激均使动脉压和心率增加。总RSNA增加到相同的程度，由两种刺激，但外部热产生了更大的肾血管收缩反应比尾部压缩，而这两种刺激增加频谱密度功率的RSNA在心脏和呼吸频率，调制RBF变异性的波动RSNA是小的，在这些频率，与值的归一化传输增益是类似的0.1在>0.5 Hz。在尾部压缩过程中，发现RSNA和RBF的相干振荡在0.3-0.4 Hz，归一化传递增益为0.33 +/- 0.02。在外部加热期间，在0.2和0.3-0.4 Hz下均发现RSNA和RBF的相干振荡，其中0.2 Hz下的归一化传递增益为0.63 +/- 0.05，0.3-0.4 Hz下的归一化传递增益为0.53 +/- 0.04至0.36 +/- 0.02。肾去神经消除了0.2和0.3-0.4 Hz的RBF振荡。这些发现表明，尽管总RSNA增加相似，但由于激活了具有不同肾血管频率响应特性的独特肾交感神经纤维群，外部加热导致比尾部压缩更大的肾血管收缩反应。
To examine the effect of activation of a unique population of renal sympathetic nerve fibers on renal blood flow (RBF) dynamics, anesthetized rats were instrumented with a renal sympathetic nerve activity (RSNA) recording electrode and an electromagnetic flow probe on the ipsilateral renal artery. Peripheral thermal receptor stimulation (external heat) was used to activate a unique population of renal sympathetic nerve fibers and to increase total RSNA. Total RSNA was reflexly increased to the same degree with somatic receptor stimulation (tail compression). Arterial pressure and heart rate were increased by both stimuli. Total RSNA was increased to the same degree by both stimuli but external heat produced a greater renal vasoconstrictor response than tail compression Whereas both stimuli increased spectral density power of RSNA at both cardiac and respiratory frequencies, modulation of RBF variability by fluctuations of RSNA was small at these frequencies, with values for the normalized transfer gain being similar to 0.1 at >0.5 Hz. During tail compression coherent oscillations of RSNA and RBF were found at 0.3-0.4 Hz with normalized transfer gain of 0.33 +/- 0.02. During external heat coherent oscillations of RSNA and RBF were found at both 0.2 and 0.3-0.4 Hz with normalized transfer gains of 0.63 +/- 0.05 at 0.2 Hz and 0.53 +/- 0.04 to 0.36 +/- 0.02 at 0.3-0.4:Hz. Renal denervation eliminated the oscillations in RBF at both 0.2 and 0.3-0.4 Hz. These findings indicate that despite similar increases in total RSNA, external heat results in a greater renal vasoconstrictor response than tail compression due to the activation of a unique population of renal sympathetic nerve fibers with different frequency-response characteristics of the renal vasculature.