Ventilatory afterdischarge in the awake goat.
Ventilatory afterdischarge in the awake goat.
复制标题
清醒山羊的通气后排出物。
DOI：
10.1152/jappl.1991.71.4.1511
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
Bisgard,GE
中科院分区：
文献类型：
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作者：
Engwall,MJ;Daristotle,L;Niu,WZ;Dempsey,JA;Bisgard,GE
通气性后放电（Ventilatory afterdischarge，VAD）是指在各种呼吸刺激消失后，呼吸活动持续逐渐减弱的现象。这种现象已在麻醉的猫、小猪和羔羊对颈动脉窦神经电刺激的反应中得到了充分的记录。我们试图确定是否VAD可以证明在站立清醒山羊（n = 7）通过使用体外电路提供方波生理刺激的颈动脉化学感受器（颈动脉体PO2 40托）。单独刺激颈动脉体5分钟后，吸入每分钟通气量、潮气量和呼吸频率减少的平均时间常数分别为27.7、34.5和25.5 s。提示清醒山羊模型中存在VAD。证实VAD的一个关键因素是在呼吸活动增加期间维持体循环动脉PCO2（等碳酸血症）。如果在过度通气期间允许动脉PCO2甚至略微降低，则VAD的幅度和持续时间会大大减弱。
Ventilatory afterdischarge (VAD) has been defined as a persistent gradually diminishing elevation of ventilatory activity that occurs after withdrawal of a variety of respiratory stimuli. The phenomenon has been well documented in the anesthetized cat, piglet, and lamb in response to electrical stimulation of the carotid sinus nerve. We sought to determine whether VAD could be demonstrated in the standing awake goat (n = 7) by use of an extracorporeal circuit to provide square-wave physiological stimulation of the carotid chemoreceptor (carotid body PO2 40 Torr). After 5 min of isolated carotid body stimulation, the mean time constants for diminishing inspired minute ventilation, tidal volume, and respiratory frequency were 27.7, 34.5, and 25.5 s, respectively. These results indicate that VAD does exist in the awake goat model. A critical factor for the demonstration of VAD is the maintenance of systemic arterial PCO2 (isocapnia) during the period of increased ventilatory activity. If arterial PCO2 is allowed to decrease even slightly during the hyperventilation, the magnitude and duration of VAD are greatly attenuated.