Zhang Y Q, Liu L
Department of Physiology, Shandong Medical University, Jinan.
Sheng Li Xue Bao. 1991 Oct;43(5):499-503.
Experiments were performed on 42 urethane-anesthetized rabbits of both sexes. The rabbits were either spontaneously breathing or gallamine paralyzed and artificially ventilated. Efferent phrenic nerve activity was recorded with bipolar silver electrodes. The experiment results were as follows: Unilateral mechanical lesion of focal block by microinjection of lidocaine (2%, 1 microliter) in the ventromedial region of nucleus facialis (VMNF) consistently caused apneustic-type breathing associated with no significant changes in the rate of rise of inspiratory activity. The expiratory time (Te) was only slightly affected or not changed at all. Some increase in Te was present only when a very strong apneustic effect was evoked. Respiratory effects of focal block by lidocaine in the region of VMNF were not accompanied by changes in blood pressure. No significant changes in respiratory rhythm were observed when lidocaine is microinjected in the nearby regions of VMNF. The results suggest that VMNF appears to be involved in an inspiratory off-switch mechanism.
实验在42只经氨基甲酸乙酯麻醉的雌雄家兔身上进行。家兔要么自主呼吸，要么用三碘季铵酚麻痹并进行人工通气。用双极银电极记录膈神经传出活动。实验结果如下：通过在面神经核腹内侧区（VMNF）微量注射利多卡因（2%，1微升）进行局灶性阻滞的单侧机械损伤，始终会导致长吸式呼吸，吸气活动上升速率无显著变化。呼气时间（Te）仅受到轻微影响或根本没有变化。只有在诱发非常强烈的长吸效应时，Te才会有所增加。利多卡因在VMNF区域进行局灶性阻滞的呼吸效应并未伴有血压变化。当在VMNF附近区域微量注射利多卡因时，未观察到呼吸节律有显著变化。结果表明，VMNF似乎参与了吸气切断机制。
