Contribution to sympathetic vasomotor tone of tonic glutamatergic inputs to neurons in the RVLM.

Contribution to sympathetic vasomotor tone of tonic glutamatergic inputs to neurons in the RVLM.
复制标题

RVLM 神经元强直性谷氨酸能输入对交感血管舒缩张力的贡献。

DOI:
10.1152/ajpregu.00255.2004
复制
发表时间:
2004
期刊:
American journal of physiology. Regulatory, integrative and comparative physiology
影响因子:
--
通讯作者:
R. Dampney
R. Dampney
中科院分区:
--
文献类型:
--
作者:
J. Horiuchi;S. Killinger;R. Dampney

文献摘要

参考文献

被引文献

相似文献

延髓头端腹外侧 (RVLM) 中的兴奋性氨基酸 (EAA) 受体在维持静息交感血管舒缩张力中的作用仍不清楚。有人提出,RVLM 中的 EAA 受体介导前交感神经元和尾侧腹外侧髓质 (CVLM) 中间神经元的兴奋性输入,然后对 RVLM 前交感神经元提供平衡抑制。在本研究中,我们通过确定抑制 CVLM 神经元后,阻断 RVLM 中的 EAA 受体对平均动脉压 (MAP)、心率 (HR) 和肾交感神经活动 (RSNA) 的影响来检验这一假设。在麻醉大鼠中,在 CVLM 双侧注射蝇蕈醇可增加 MAP、HR 和 RSNA。随后在 RVLM 中双侧注射犬尿酸(Kyn,2.7 nmol)导致 MAP 适度降低约 20 mmHg,但与单独注射媒介物的效果相比,对 HR 或 RSNA 没有影响。在 RVLM 中注射 Kyn 或载体后大约 50 分钟,MAP 已稳定在接近其原始基线水平的水平,但 HR 和 RSNA 稳定在高于基线的水平。结果表明,即使来自 CVLM 的输入被阻断,去除 RVLM 神经元的强直 EAA 驱动对 RVLM 前交感神经元的强直活动影响也很小。因此,在这些条件下,RVLM 前交感神经元的强直活性取决于非 EAA 受体介导的兴奋性突触输入和/或这些神经元的自身活动。
The role of excitatory amino acid (EAA) receptors in the rostral ventrolateral medulla (RVLM) in maintaining resting sympathetic vasomotor tone remains unclear. It has been proposed that EAA receptors in the RVLM mediate excitatory inputs both to presympathetic neurons and to interneurons in the caudal ventrolateral medulla (CVLM), which then provide a counterbalancing inhibition of RVLM presympathetic neurons. In this study, we tested this hypothesis by determining the effect of blockade of EAA receptors in the RVLM on mean arterial pressure (MAP), heart rate (HR), and renal sympathetic nerve activity (RSNA), after inhibition of CVLM neurons. In anesthetized rats, bilateral injections of muscimol in the CVLM increased MAP, HR, and RSNA. Subsequent bilateral injections of kynurenic acid (Kyn, 2.7 nmol) in the RVLM caused a modest reduction of approximately 20 mmHg in the MAP but had no effect, when compared with the effect of vehicle injection alone, on HR or RSNA. By approximately 50 min after the injections of Kyn or vehicle in the RVLM, the MAP had stabilized at a level close to its original baseline level, but the HR and RSNA stabilized at levels above baseline. The results indicate that removal of tonic EAA drive to RVLM neurons has little effect on the tonic activity of RVLM presympathetic neurons, even when inputs from the CVLM are blocked. Thus the tonic activity of RVLM presympathetic neurons under these conditions is dependent on excitatory synaptic inputs mediated by non-EAA receptors and/or the autoactivity of these neurons.
动脉压力感受器和迷走神经对大鼠髓质交感兴奋神经元的输入。
DOI: 10.1152/ajpregu.1987.252.4.r699
发表时间: 1987
期刊: The American journal of physiology
影响因子: --
作者:
Sun,MK;Guyenet,PG
通讯作者: Guyenet,PG
GABA 介导的压力感受器抑制网状脊髓神经元。
DOI: 10.1152/ajpregu.1985.249.6.r672
发表时间: 1985
期刊: The American journal of physiology
影响因子: --
作者:
Sun,MK;Guyenet,PG
通讯作者: Guyenet,PG
DOI: 10.1161/01.hyp.35.1.413
发表时间: 2000-01-01
期刊: HYPERTENSION
影响因子: 8.3
作者:
Ito, S;Komatsu, K;Sved, AF
通讯作者: Sved, AF