Simbulan D, Tadaki E, Kozaki Y, Eguchi K, Kumazawa T
Department of Nervous and Sensory Functions, Nagoya University, Japan.
Jpn J Physiol. 1990;40(2):253-72. doi: 10.2170/jjphysiol.40.253.
Vagal influence on the facilitation of phrenic neural activity during respiratory phase-locked, gastrocnemius muscle nerve nociceptive electrical stimulation was examined in anesthetized, glomectomized, paralyzed, and artificially ventilated cats. (1) In the vagi-intact state, respiratory reflex facilitation was characterized by a sharp rise in peak amplitude, maximum rate of rise or slope, and mean rate of rise of integrated phrenic nerve activity. This was greater during inspiratory phase-locked (T1-locked) muscle nerve electrical stimulation than during expiratory phase-locked (TE-locked) muscle nerve electrical stimulation. "Evoked post-inspiratory phrenic activity" during the early expiratory phase was also observed during TE-locked muscle nerve electrical stimulation. (2) Bilateral vagotomy significantly attenuated the respiratory facilitation during both T1- and TE-locked muscle nerve electrical stimulation. In particular, the "evoked post-inspiratory phrenic activity" during TE-locked muscle nerve electrical stimulation was also attenuated or almost completely abolished. (3) Conditioning electrical stimulation of the vagus nerve revealed facilitatory reflexes which co-exist with inspiratory inhibitory reflexes. (4) The "evoked post-inspiratory phrenic activity" during TE-locked muscle nerve electrical stimulation, which was attenuated or abolished after vagotomy, was restored after vagal T1-locked conditioning stimuli combined with TE-locked muscle nerve electrical stimulation. The results suggest that vagal facilitatory reflexes augment the respiratory reflex facilitation during muscle nociceptive stimulation.
在麻醉、切除肾小球、麻痹并进行人工通气的猫身上，研究了迷走神经对呼吸锁相期间膈神经活动促进作用的影响，此时腓肠肌神经受到伤害性电刺激。（1）在迷走神经完整状态下，呼吸反射促进作用的特征是膈神经活动的峰值幅度、最大上升速率或斜率以及积分膈神经活动的平均上升速率急剧上升。吸气锁相（T1锁相）肌肉神经电刺激期间的这种促进作用比呼气锁相（TE锁相）肌肉神经电刺激期间更大。在TE锁相肌肉神经电刺激期间，呼气早期还观察到“诱发的吸气后膈神经活动”。（2）双侧迷走神经切断术显著减弱了T1锁相和TE锁相肌肉神经电刺激期间的呼吸促进作用。特别是，TE锁相肌肉神经电刺激期间的“诱发的吸气后膈神经活动”也减弱或几乎完全消失。（3）对迷走神经进行条件性电刺激显示，促进性反射与吸气抑制性反射共存。（4）TE锁相肌肉神经电刺激期间的“诱发的吸气后膈神经活动”，在迷走神经切断术后减弱或消失，在迷走神经T1锁相条件刺激与TE锁相肌肉神经电刺激相结合后恢复。结果表明，迷走神经促进性反射增强了肌肉伤害性刺激期间的呼吸反射促进作用。
