股动脉注射琥珀胆碱诱发肌梭传入对膈神经放电的影响

目的 观察肌梭传入活动是否对呼吸运动具有反射性调节作用。方法 实验用63只麻醉、制动、切断双侧颈迷走神经、肌松、人工呼吸的家兔，以膈神经放电作为呼吸观测指标，观察股动脉注射琥珀胆碱(Succinylcholine,Sch)诱发肌梭传入活动对呼吸的影响。结果 ①产生易化作用的有40例(63..49%)，其中23例(36..51%)呈吸气延长效应；17例(26..98%)呈抑呼增频效应。产生抑制效应的有11例(17..46%)，呈双相反应的4例(6..35%)，8例(12..70%)无明显作用。②吸气延长效应主要表现为吸气时程(Ti)延长，呼吸时程(Te)有缩短趋势，但差异无显著性，Ti/Te比值增加，呼吸频率(RF)变化不明显；抑呼增频效应主要表现为Te缩短，Ti变化不明显，Ti/Te比值增加，RF加快。③肌注布比卡因破坏肌梭后，同剂量的Sch使上述呼吸易化效应明显减弱。结论 股动脉注射Sch诱发的肌梭传入活动对呼吸运动具有明显的增强作用。

Effects of muscle spindle afferents invoked by intraarterial injection of succinylcholine on the phrenic nerve discharges

Objective To study wether muscle spindle afferents have the regulating effects on respiratory movement. Methods Experiments were performed on 36 anesthetized, immobilized, bilaterally vagotomized and artificially ventilated rabbits. Using the phrenic nerve discharge as the respiratory index, this experiment have assessed the effects of muscle spindle afferents invoked by intraarterial injection of succinylcholine(Sch) on respiration. Results ①In 40(63.49% ) cases which had the facilitated effects, 23 (36.51%) cases had the effect of prolonged inspiratory phase and 17 (26.98 % ) cases had the effect of attenuated expiratory phase and augmented respiratory frequency. In addition,there were 11(17.46% ) cases which had the attenuated effects,and 4(6.35% ) cases which had the biphasic effects,and 8(12.7% ) cases which had no effects;②The effect of prolonged inspiratory phase mainly showed the prolongation of inspiratory duration(Ti), but the effect of attenuated expiratory phase and augmented respiratory frequency mainly showed the decrease of expiratory duration (Te) and the augmentation of respiratory frequency(RF) ;③The above facilitated effects of Sch were significantly attenuated by intramuscular application of bupivacaine to destroy the muscle spindles. Conclusion These results suggest that muscle spindle afferents induced by intraarterial injection Sch have a significant facilitated effect on respiration.