摘要
以持续时间为5～10s 的连续单相方波脉冲(波宽0.5ms.频率50Hz,电流强度10～100μA,刺激应用异戌巴比妥钠麻醉、三碘季胺酚麻痹并切断双侧颈迷走神经的兔下丘脑乳头体核及其周围区域。可引起以快速性心律失常为主的心电图改变。此反应稳定,可重复性甚佳。刺激切断后的颈迷走神经中枢端,可以抑制上述心律失常的出现,肺内注气可获得与刺激颈迷走神经中枢端相似的效应.机械扩张胃或刺激膈下迷走神经,不能抑制上述心律失常的出现。刺激迷走神经的分支喉上神经.刺激坐骨神经或其分支腓深神经也不能抑制上述心律失常的出现.
(1)Various kinds of arrhythimias could be elicited by stimulation of the hypothalamic mamillary nucleus and its surrounding region with monophasic square pluses train (lasted for 5～10 sec,frequency 50 Hz,duration 0.5 ms,intensity 10～100μA) in rabbits bilaterally cervically vagotomized,anaesthelized with sodium amobarbital(33 mg/kg,i.v) and immobi- lized with faxedil.(2)The arrhythimia could be partially or completely arrested by stimula- tion of the central end of cervical vagus.The same inhibitory effect could be elicited by forced inflation of the lungs.(3)Forced distension of the stomach,stimulation of the subdiaphrag- matic portion of the vagi,of the superior laryngeal nerves,of sciatic nerve or.unilateral deep peroneal nerve could not arrested the arrhythimias.(4)A discussion on the central mecha- nism of inhibitory effect of stimulation of the vagus on the arrhythimias was given.
关键词
下丘脑
心律失常
迷走神经
hypothalamus
cardiac arrhythmias
vagus
