Autonomic mechanisms underpinning the stress response in borderline hypertensive rats
Autonomic mechanisms underpinning the stress response in borderline hypertensive rats
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支持边缘性高血压大鼠应激反应的自主神经机制
作者：
O. Sarenac;M. Lozić;S. Drakulić;D. Bajić;J. Paton;D. Murphy;N. Japundzic
本研究研究了成年临界高血压大鼠和正常盐饮食的血压正常对照动物的血压（BP）和心率（HR）短期变异性和自发压力反射功能。通过无线电遥测记录动脉脉压。分别用频谱分析法和序列法测定收缩压、舒张压、心率变异性和压力感受性反射。在所有实验条件下（基线和应激），临界高血压大鼠表现出较高的血压，增加压力反射敏感性和重置，相对于对照组动物。急性振动应激（单次暴露于200个周期/min的振动平台）使两种品系的血压升高，而慢性振动应激（暴露于振动平台3天）仅使临界高血压大鼠的收缩压升高。低频和高频HR变异性仅在对照动物中增加，以响应急性和慢性振动器（单次暴露于限制器）应激。急性束缚应激使两种品系的血压、心率、血压和心率的低频和高频变异性增加的程度大于急性振动应激。只有血压正常的大鼠表现出低频率与高频率HR变异性的比率降低，表明迷走神经心脏控制占主导地位。在临界高血压大鼠中，而不是在对照动物中，慢性束缚应激（9天暴露于束缚器）增加了低频和高频BP和HR变异性及其比值，表明向交感心血管控制转变。结论：临界性高血压大鼠在基础状态和应激状态下血压的维持与压力感受性反射敏感性增强和重调有关。交感迷走神经控制的不平衡仅在临界高血压大鼠暴露于应激源时才明显。
This study investigates blood pressure (BP) and heart rate (HR) short‐term variability and spontaneous baroreflex functioning in adult borderline hypertensive rats and normotensive control animals kept on normal‐salt diet. Arterial pulse pressure was recorded by radio telemetry. Systolic BP, diastolic BP and HR variabilities and baroreflex were assessed by spectral analysis and the sequence method, respectively. In all experimental conditions (baseline and stress), borderline hypertensive rats exhibited higher BP, increased baroreflex sensitivity and resetting, relative to control animals. Acute shaker stress (single exposure to 200 cycles min‐1 shaking platform) increased BP in both strains, while chronic shaker stress (3‐day exposure to shaking platform) increased systolic BP in borderline hypertensive rats alone. Low‐ and high‐frequency HR variability increased only in control animals in response to acute and chronic shaker (single exposure to restrainer) stress. Acute restraint stress increased BP, HR, low‐ and high‐frequency variability of BP and HR in both strains to a greater extent than acute shaker stress. Only normotensive rats exhibited a reduced ratio of low‐ to high‐frequency HR variability, pointing to domination of vagal cardiac control. In borderline hypertensive rats, but not in control animals, chronic restraint stress (9‐day exposure to restrainer) increased low‐ and high‐frequency BP and HR variability and their ratio, indicating a shift towards sympathetic cardiovascular control. It is concluded that maintenance of BP in borderline hypertensive rats in basal conditions and during stress is associated with enhanced baroreflex sensitivity and resetting. Imbalance in sympathovagal control was evident only during exposure of borderline hypertensive rats to stressors.
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临界高血压大鼠的心血管和肾脏对应激的反应。
DOI：
10.1152/ajpregu.1988.255.3.r431
发表时间：
1988
期刊：
The American journal of physiology
影响因子：
--
作者：
Sanders,BJ;Cox,RH;Lawler,JE
通讯作者：
Lawler,JE
临界高血压大鼠的中枢α2-肾上腺素受体反应性。
影响因子：
4.9
作者：
DiBona,GF;Jones,SY
通讯作者：
Jones,SY
BHR 中行为压力对冠状动脉舒张的影响随着年龄的增长而改变。
DOI：
10.1152/ajpregu.1999.276.2.r435
发表时间：
1999
期刊：
The American journal of physiology
影响因子：
--
作者：
Giulumian,AD;Clark,SG;Fuchs,LC
通讯作者：
Fuchs,LC
临界高血压压力反射控制的无创评估。
DOI：
10.1161/01.hyp.28.2.238
发表时间：
1996
期刊：
Hypertension (Dallas, Tex. : 1979)
影响因子：
--
作者：
Watkins,LL;Grossman,P;Sherwood,A
通讯作者：
Sherwood,A