Neuronal excitation by angiotensin II in the rostral ventrolateral medulla of the rat in vitro.
Neuronal excitation by angiotensin II in the rostral ventrolateral medulla of the rat in vitro.
复制标题
体外大鼠延髓头端腹外侧区血管紧张素 II 的神经元兴奋。
DOI：
10.1152/ajpregu.1995.268.1.r272
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Guyenet,PG
中科院分区：
文献类型：
--
作者：
Li,YW;Guyenet,PG
我们研究了血管紧张素II（ANG II）对大鼠延髓头端腹外侧（RVLM）切片自发单位活动的影响。ANG II（1-3 μ M）兴奋了61%的缓慢和不规则放电的RVLM神经元（给药前，1.2 +/- 0.1峰/s;给药后，4.6 +/- 0.3峰/s; n = 52）。ANG II对起搏器样快速放电神经元没有影响（前药，8.6 +/- 0.4峰/s; n = 33）。ANG II对缓慢放电细胞的作用是可重复的，并且通过3 μ M氯沙坦降低75%（基线，1.7 +/- 0.4个尖峰/s; ANG II，5.3 +/- 0.7个尖峰/s; ANG II+氯沙坦，2.4 +/- 0.6个尖峰/s; n = 12）。缓慢放电神经元的持续活动不受0.5-1 mM犬尿烯酸（离子型兴奋性氨基酸受体拮抗剂）的影响。大多数ANG II反应神经元（10/11）被α 2-肾上腺素能受体激动剂UK-14，304抑制，但起搏器样神经元没有。总之，RVLM含有由AT 1受体激动剂兴奋的神经元。这些神经元不同于先前描述的起搏器非肾上腺素能前交感细胞。它们可能是在体RVLM内注射ANG Ⅱ产生升压效应的原因。
We examined the effects of angiotensin II (ANG II) on spontaneous unit activity in slices of the rat rostral ventrolateral medulla (RVLM), ANG II (1-3 microM) excited 61% of a population of slowly and irregularly firing RVLM neurons (predrug, 1.2 +/- 0.1 spikes/s; postdrug, 4.6 +/- 0.3 spikes/s; n = 52). ANG II had no effect on pacemaker-like rapidly firing neurons (predrug, 8.6 +/- 0.4 spikes/s; n = 33). The effect of ANG II on slowly firing cells was repeatable and was reduced 75% by 3 microM losartan (baseline, 1.7 +/- 0.4 spikes/s; ANG II, 5.3 +/- 0.7 spikes/s; ANG II+losartan, 2.4 +/- 0.6 spikes/s; n = 12). The ongoing activity of slowly firing neurons was unaffected by 0.5-1 mM kynurenic acid (an ionotropic excitatory amino acid receptor antagonist). Most ANG II-responsive neurons (10 of 11) were inhibited by the alpha 2-adrenergic receptor agonist UK-14,304, but pacemaker-like neurons were not. In conclusion, the RVLM contains neurons excited by AT1 receptor agonists. These neurons are distinct from the previously described pacemaker nonadrenergic presympathetic cells. They may be responsible for the pressor effects produced by injecting ANG II into the RVLM in vivo.