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低氧增强清醒自发性高血压大鼠心血管-呼吸活动

田彦明, 马兰, 耿丹阳, 袁芳, 张翼, 王升^*

河北医科大学生理学教研室，石家庄 050017

摘要

激活外周化学感受器可以同时引起呼吸和心血管反射，此机制可能参与高血压形成过程中的交感神经过度激活。因此我们推测激活外周呼吸化学感受器可以显著增强高血压大鼠的心肺活动。本研究通过联合应用全身无创全体积描记术和无线生物信号遥测技术，观察急性低氧刺激对清醒自发性高血压大鼠(spontaneously hypertensive rat, SHR)和血压正常的对照Wistar-Kyoto (WKY)大鼠的肺通气、动脉血压和心率的影响。结果表明，急性低氧刺激引起SHR潮气量和每分通气量明显高于WKY大鼠，并且急性低氧引起SHR血压和心率的增加幅度更明显。切断支配大鼠颈动脉体的双侧窦神经后，SHR和WKY大鼠急性低氧通气反应均降低，并且两组间比较没有显著性差异。同时，在切断双侧窦神经后，急性低氧引起的两组动物的血压和心率变化均无显著性差异。本研究表明，急性低氧刺激显著增强SHR的心血管和呼吸效应，这可能与其颈动脉体外周呼吸化学感受器对低氧的敏感性增高有关。

关键词： 颈动脉体; 肺通气; 高血压; 低氧

分类号：Q46

Amplified cardiorespiratory activity by hypoxia in conscious spontaneously hypertensive rats

TIAN Yan-Ming, MA Lan, GENG Dan-Yang, YUAN Fang, ZHANG Yi, WANG Sheng^*

Department of Physiology, Hebei Medical University, Shijiazhuang 050017, China

Abstract

Activation of peripheral respiratory chemoreceptors provokes respiratory and cardiovascular reflexes, providing a novel understanding of pathogenic mechanism of hypertension. Here we hypothesize that activation of peripheral respiratory chemoreceptors by hypoxia causes enhanced cardiorespiratory activity in conscious spontaneously hypertensive rats (SHRs). Using whole body plethysmography in combination with radio telemetry, pulmonary ventilation, arterial blood pressure and heart rate were examined in SHRs and Wistar-Kyoto (WKY) rats. We found that exposure to hypoxia induced greater increases in tidal volume and minute ventilation volume in SHRs compared to WKY rats. In addition, hypoxia caused a robust increase in arterial blood pressure and heart rate in SHRs relative to WKY counterparts. After carotid body denervation, the hypoxic ventilatory response was significantly decreased in both SHRs and WKY rats, but without significant difference between the two strains; moreover, the differences of arterial blood pressure and heart rate changes during hypoxic exposure were statistically insignificant between SHRs and WKY rats. It is concluded that hypoxia remarkably potentiates cardiorespiratory activity in the SHRs, suggesting an enhanced sensitivity of carotid bodies to hypoxia.

Key words: Carotid body; ventilation; hypertension; hypoxia

收稿日期：2018-10-23　　录用日期：2019-02-14

通讯作者：王升　　E-mail: wangsheng@hebmu.edu.cn

DOI: 10.13294/j.aps.2019.0023

引用本文：

田彦明, 马兰, 耿丹阳, 袁芳, 张翼, 王升. 低氧增强清醒自发性高血压大鼠心血管-呼吸活动[J]. 生理学报 2019; 71 (4): 503-513.

TIAN Yan-Ming, MA Lan, GENG Dan-Yang, YUAN Fang, ZHANG Yi, WANG Sheng. Amplified cardiorespiratory activity by hypoxia in conscious spontaneously hypertensive rats. Acta Physiol Sin 2019; 71 (4): 503-513