Jakus J, Tomori Z, Bosel'ová L, Nagyová B, Kubinec V
Department of Physiology, Faculty of Medicine, Comenius University, Martin.
Physiol Bohemoslov. 1987;36(4):329-40.
The effect of brain stem transection at different levels of the pons Varolii and the medulla oblongata on respiration and on cough and the aspiration and expiration reflex elicited by mechanical stimulation of the relevant parts of the respiratory tract was studied in experiments on 13 anaesthetized, unparalyzed cats. The results of 142 respiratory reflex elicitation tests showed that: 1. Compared with the control state, transection of the upper and middle part of the pons Varolii and transection at the level of the pontomedullary junction reduced the respiration rate (p less than 0.001), increased the duration of inspiration and expiration (p less than 0.001, transection 10 mm rostrally to the obex) and gave rise to apneustic breathing (8 mm), or to tonic, respiration-modulated activity of the phrenic nerve and diaphragm (6 mm). 2. Successive transection of the pons and the pontomedullary junction region led chiefly to a drop in maximum expiratory pleural pressure values (p less than 0.01-0.001) during cough and the expiration reflex and to a drop in maximum inspiratory pleural pressure values during the aspiration reflex (p less than 0.02-0.001). 3. Transection of the upper part of the medulla oblongata always led to permanent arrest of rhythmic respiration, during which cough and the expiration reflex could not be elicited while the aspiration reflex persisted (though in a weakened form). This state was followed by gasping, during which only a highly elicitable aspiration reflex persisted. 4. It can be assumed from the above findings that the central mechanisms responsible for the development of powerful expiratory efforts in cough and the expiration reflex could be localized in the pons Varolii, while those integrating the aspiration reflex are probably localized mainly in the medulla oblongata.
在13只麻醉且未瘫痪的猫身上进行实验，研究在脑桥不同水平以及延髓横断脑干对呼吸、咳嗽以及机械刺激呼吸道相关部位引发的吸气和呼气反射的影响。142次呼吸反射诱发试验的结果表明：1. 与对照状态相比，脑桥上部和中部横断以及脑桥延髓交界处横断会降低呼吸频率（p<0.001），增加吸气和呼气持续时间（p<0.001，在闩前方10毫米处横断），并导致长吸式呼吸（8毫米处横断），或膈神经和膈肌的紧张性、呼吸调制活动（6毫米处横断）。2. 脑桥和脑桥延髓交界区的连续横断主要导致咳嗽和呼气反射期间最大呼气胸膜腔内压值下降（p<0.01 - 0.001），以及吸气反射期间最大吸气胸膜腔内压值下降（p<0.02 - 0.001）。3. 延髓上部横断总是导致节律性呼吸永久停止，在此期间无法引发咳嗽和呼气反射，而吸气反射持续存在（尽管形式减弱）。这种状态之后是喘息，在此期间只有高度可诱发的吸气反射持续存在。4. 从上述发现可以推测，负责咳嗽和呼气反射中强力呼气努力发展的中枢机制可能位于脑桥，而整合吸气反射的机制可能主要位于延髓。
