Central command does not supress baroreflex control of cardiac sympathetic nerve activity at the onset of spontaneous motor activity in the decerebrate cat
Central command does not supress baroreflex control of cardiac sympathetic nerve activity at the onset of spontaneous motor activity in the decerebrate cat
复制标题
在去大脑猫自发运动活动开始时，中央命令不会抑制心脏交感神经活动的压力反射控制
DOI：
10.1152/japplphysiol.00299.2016
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发表时间：
2016
影响因子：
3.3
通讯作者：
Idesako M
中科院分区：
文献类型：
--
作者：
Matsukawa K;Ishii K;Asahara R;Idesako M
我们的实验室报告说，中央命令钝化的敏感性，主动脉压力感受器心率（HR）反射在开始自愿静态运动的动物。我们已经研究了压力反射控制的心脏交感神经活动（CSNA）和/或心迷走神经压力反射敏感性是否改变自发发生的运动行为，这是监测与胫神经活动瘫痪，去大脑猫的发病。运动开始后，CSNA立即出现峰值增加（126 ± 17%），随后HR和平均动脉压（MAP）增加。随着升压反应的发展，CSNA和HR下降接近基线，尽管自发运动活动没有终止。硝酸甲酯阿托品（0.1- 0.2mg/kg，iv）对中枢影响不大，可延迟HR的初始增加，但不改变HR和CSNA的反应幅度，而增加升压反应。在自发运动活动开始时，对腹主动脉短暂闭塞引起的压力感受性反射诱导的CSNA和HR降低进行了挑战。自发运动活动减弱了主动脉阻断引起的HR压力反射降低，但没有改变CSNA的压力反射抑制作用。同样，阿托品取消了HR的压力反射降低，但不影响CSNA的压力反射抑制。因此，这是可能的，中央命令增加CSNA和减少心脏迷走神经流出在自发运动活动的开始，同时保持CSNA的压力反射控制。因此，中央指令必须减弱心迷走神经压力感受性反射敏感性对MAP的过度上升，估计从毒蕈碱阻滞的效果。
Our laboratory has reported that central command blunts the sensitivity of the aortic baroreceptor-heart rate (HR) reflex at the onset of voluntary static exercise in animals. We have examined whether baroreflex control of cardiac sympathetic nerve activity (CSNA) and/or cardiovagal baroreflex sensitivity are altered at the onset of spontaneously occurring motor behavior, which was monitored with tibial nerve activity in paralyzed, decerebrate cats. CSNA exhibited a peak increase (126 ± 17%) immediately after exercise onset, followed by increases in HR and mean arterial pressure (MAP). With development of the pressor response, CSNA and HR decreased near baseline, although spontaneous motor activity was not terminated. Atropine methyl nitrate (0.1-0.2 mg/kg iv) with little central influence delayed the initial increase in HR but did not alter the response magnitudes of HR and CSNA, while atropine augmented the pressor response. The baroreflex-induced decreases in CSNA and HR elicited by brief occlusion of the abdominal aorta were challenged at the onset of spontaneous motor activity. Spontaneous motor activity blunted the baroreflex reduction in HR by aortic occlusion but did not alter the baroreflex inhibition of CSNA. Similarly, atropine abolished the baroreflex reduction in HR but did not influence the baroreflex inhibition of CSNA. Thus it is likely that central command increases CSNA and decreases cardiac vagal outflow at the onset of spontaneous motor activity while preserving baroreflex control of CSNA. Accordingly, central command must attenuate cardiovagal baroreflex sensitivity against an excess rise in MAP as estimated from the effect of muscarinic blockade.