Baekey David M, Dick Thomas E, Paton Julian F R
Department of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Case Western Reserve University, 11100 Euclid Avenue, Room 622 - Mailstop 5067, Cleveland, OH 44106-5067, USA.
Exp Physiol. 2008 Jul;93(7):803-16. doi: 10.1113/expphysiol.2007.041400. Epub 2008 Mar 14.
Previous studies have indicated a major role for the pons in the genesis of the respiratory pattern. The respiratory rhythm is coupled to the cardiovascular system to ensure optimal matching of minute ventilation and cardiac output. Since much of this coupling results from cross-talk between brainstem circuits, we have assessed the role of the pons in both the co-ordination of respiratory and cardiovascular efferent activities and the baroreceptor reflex efficacy. Using the arterially perfused in situ rat preparation, we recorded neural activities from the left phrenic nerve, central end of the vagus nerve, thoracic sympathetic chain (T8-T10) and heart rate. Respiratory sinus arrhythmia, respiratory modulation of sympathetic nerve activity (and Traube-Hering waves in arterial pressure) and postinspiratory discharges recorded from vagal efferents were eliminated after pontine transection. We also found that although the sympathetic arterial baroreflex remained intact, respiratory gating of the baroreceptor reflex (i.e. both bradycardia and sympathoinhibition) was abolished after pontine removal. We propose that neural activity of the pons is essential for physiological coupling of centrally generated respiratory and cardiovascular efferent activities.
以往的研究表明，脑桥在呼吸模式的产生中起主要作用。呼吸节律与心血管系统相耦合，以确保每分通气量与心输出量的最佳匹配。由于这种耦合很大程度上源于脑干回路之间的相互作用，我们评估了脑桥在呼吸和心血管传出活动协调以及压力感受器反射效能中的作用。利用动脉灌注的原位大鼠标本，我们记录了左侧膈神经、迷走神经中枢端、胸交感神经链（T8-T10）的神经活动以及心率。脑桥横断后，呼吸性窦性心律不齐、交感神经活动的呼吸调节（以及动脉血压中的Traube-Hering波）和迷走神经传出纤维记录到的吸气后放电均消失。我们还发现，尽管交感神经动脉压力反射保持完整，但脑桥切除后，压力感受器反射的呼吸门控（即心动过缓和交感神经抑制）被消除。我们认为，脑桥的神经活动对于中枢产生的呼吸和心血管传出活动的生理耦合至关重要。
