Cardiovascular responses elicited by continuous versus intermittent electrical stimulation of the aortic depressor nerve in conscious rats
Cardiovascular responses elicited by continuous versus intermittent electrical stimulation of the aortic depressor nerve in conscious rats
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DOI：
10.1016/j.lfs.2016.02.033
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发表时间：
2016-03-01
期刊：
影响因子：
6.1
通讯作者：
Salgado, Helio C.
中科院分区：
文献类型：
--
作者：
Brognara, Fernanda;Martins Dias, Daniel P.;Salgado, Helio C.
目的：在有意识的大鼠中，短期（秒或分钟）持续电激活主动脉降压神经（ADN）已成功用于研究实验性高血压、心力衰竭和外周炎症的气压传入功能。本研究的目的是表征较长时间（60分钟）连续或间歇电压力反射激活引起的血流动力学反应。主要方法：Wistar大鼠左ADN周围植入电极，股动脉内置入导管。记录随机分配进行连续或间歇电刺激的受试者的收缩压、舒张压、平均动脉压和心率。在长时间（60 min）连续（n = 6）或间歇（5 s开/3 s关；n = 10） ADN电刺激（0.5 mA; 0.25 ms; 30 Hz）时，检测有意识大鼠心血管反应的时间过程。主要发现：持续刺激下的快速（20秒）降压反应更大，但在心动过缓反应中没有发现差异。只有持续刺激才能维持降压反应，而两种方案均未观察到持续的心动过缓。意义：这些发现表明，持续刺激ADN在较长时间（60分钟）的刺激下更有效地降低动脉压。然而，连续或间歇两种治疗方案都不能引起持续的心动过缓。(C) 2016 Elsevier Inc.版权所有。
Aims: Short-term (seconds or minutes) continuous electrical activation of the aortic depressor nerve (ADN) in conscious rats has been successfully used to investigate baroafferent function in experimental hypertension, heart failure, and peripheral inflammation. The aimof this studywas to characterize the hemodynamic responses elicited by longer periods (60 min) of continuous or intermittent electrical baroreflex activation.Main methods: Wistar rats were implanted with an electrode around the left ADN and a catheter into a femoral artery. The systolic, diastolic and mean arterial pressure and heart rate were recorded in subjects randomly assigned to continuous or intermittent electrical stimulation. The time-course of cardiovascular responses in conscious rats was examined during longer-term (60 min) continuous (n = 6) or intermittent (5 s ON/3 s OFF; n = 10) electrical stimulation (0.5 mA; 0.25 ms; 30 Hz) of the ADN.Key findings: The prompt (20 s) hypotensive response was greater under continuous stimulation, but no difference was detected in the bradycardic response. The hypotensive response was sustained only by continuous stimulation while no sustained bradycardia was observed in either protocol.Significance: These findings indicate that continuous stimulation of the ADN is more effective in reducing arterial pressure over a longer period (60 min) of stimulation. Nevertheless, both protocols-continuous or intermittent were unable to elicit a sustained bradycardia. (C) 2016 Elsevier Inc. All rights reserved.