Cardiorespiratory reflex control in rats with left ventricular dysfunction.
Cardiorespiratory reflex control in rats with left ventricular dysfunction.
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左心室功能障碍大鼠的心肺反射控制。
DOI：
10.1152/ajpheart.1995.268.1.h218
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Thames,MD
中科院分区：
文献类型：
--
作者：
Jung,R;Dibner-Dunlap,ME;Gilles,MA;Thames,MD
心力衰竭患者表现出神经体液兴奋状态和心血管系统的异常压力反射控制。我们确定了在慢性心肌梗死引起的左心室功能不全（LVD）期间，在没有充血性心力衰竭的情况下，动脉压力反射是否受损，以及异常的中枢机制是否有助于这种损害。用苯肾上腺素增加动脉压，刺激有和无LVD的麻醉大鼠的压力感受器。记录腰交感神经和膈神经活动以及心率。根据梗死面积将大鼠分为不同的组。中度LVD的大鼠表现出交感神经、交感神经和心率反应的压力反射控制受损。压力反射增益与梗死面积呈负相关。通过电刺激主动脉减压神经获得的交感神经活动的中枢增益也受损。因此，在没有充血性心力衰竭的情况下，中度LVD大鼠的心肺系统压力反射控制受损。压力反射减弱可能是由于异常的传入机制，虽然中枢机制有助于受损的压力交感神经反射。
Patients with heart failure exhibit a neurohumoral excitatory state and abnormal baroreflex control of the cardiovascular system. We determined whether arterial baroreflexes are impaired during left ventricular dysfunction (LVD) caused by chronic myocardial infarction in the absence of congestive heart failure and whether abnormal central mechanisms contribute to this impairment. Baroreceptors were stimulated in anesthetized rats with and without LVD by increasing arterial pressure with phenylephrine. Lumbar sympathetic nerve and phrenic nerve activity as well as heart rate were recorded. Rats were divided into different groups based on infarct size. Rats with moderate LVD showed impaired baroreflex control of sympathetic, ventilatory, and heart rate responses. Baroreflex gains were inversely related to the size of the infarct. The central gain for sympathetic nerve activity, obtained by using electrical stimulation of the aortic depressor nerve, also was impaired. Baroreflex control of the cardiorespiratory system is thus impaired in rats with moderate LVD in the absence of congestive heart failure. The attenuated baroreflexes are likely due to abnormal afferent mechanisms, although central mechanisms contribute to the impaired barosympathetic reflex.