Grogaard J, Lindstrom D P, Stahlman M T, Marchal F, Sundell H
J Dev Physiol. 1982 Dec;4(6):353-70.
The cardiovascular response to administration of water to the larynx was studied in unanesthetized newborn lambs. The cardiovascular components of this laryngeal reflex response consisted of a decrease in heart rate associated with a decrease in cardiac output, an increase in systemic and pulmonary vascular resistance associated with increased blood pressure and blood flow redistribution. Blood flow decreased in carcass, kidneys, intestines, liver and spleen and increased in head, brain and heart. The magnitude of the separate components of the cardiovascular response correlated significantly with each other and with the respiratory response. Alpha-adrenergic blockade eliminated the blood pressure and blood flow redistribution response. Atropine blocked the heart rate response. The reflex-elicited decrease in cardiac output and the increase in systemic vascular resistance were augmented by beta-adrenergic blockade. The cardiovascular responses were diminished, but not abolished, when oxygenation and rhythmic ventilation were artificially maintained during laryngeal water stimulation. These results indicate the possible interaction with the arterial chemoreceptors, stimulated by the concomitant 26 torr decrease in arterial oxygen tension, as well as with the cessation of the pulmonary inflation reflex associated with the apnoea.
在未麻醉的新生羔羊中研究了向喉部注水时的心血管反应。这种喉部反射反应的心血管组成部分包括心率下降伴心输出量减少、全身和肺血管阻力增加伴血压升高和血流重新分布。躯体、肾脏、肠道、肝脏和脾脏的血流量减少，而头部、大脑和心脏的血流量增加。心血管反应各单独组成部分的幅度彼此之间以及与呼吸反应之间均存在显著相关性。α-肾上腺素能阻滞消除了血压和血流重新分布反应。阿托品阻断了心率反应。β-肾上腺素能阻滞增强了反射引起的心输出量减少和全身血管阻力增加。当在喉部水刺激期间人工维持氧合和节律性通气时，心血管反应减弱但未消除。这些结果表明，可能与动脉化学感受器相互作用，这是由动脉血氧张力同时下降26托所刺激的，以及与呼吸暂停相关的肺膨胀反射的停止有关。
