损毁迷走神经背核翻转室旁核降低胃内压的观察

选用ＳＤ大鼠３８只，乌拉坦麻醉下观察电刺激下丘脑室旁核（ＰＶＮ）对大鼠胃内压的影响以及侧脑室注射阿托品和双侧迷走神经背核被损毁后翻转ＰＶＮ降低胃内压（ＩＧＰ）的效应。其结果是：（１）电刺激ＰＶＮ可明显降低胃内压（刺激前ＩＧＰ为０．６２±０．０１ｋＰａ，刺激后ＩＧＰ降至０．３９±０．０１ｋＰａ．Ｐ＜０．０１）；胃内压变化率为３７．１％。（２）侧脑室内微注射阿托品可明显减弱电刺激ＰＶＮ对ＩＧＰ的影响，有５只大鼠出现胃位相性收缩波。（３）直流损毁双侧迷走神经背核后，则电刺激ＰＶＮ引起的ＩＧＰ下降效应明显减弱，出现胃内压翻转效应（由刺激前的０．６０±０．１７ｋＰａ升高至０．８０±０．３ｋＰａ，Ｐ＜０．０５）；胃内压变化率为＋３３．３％。有８只大鼠出现胃位相性收缩波增强。本实验结果表明：中枢胆碱能神经系统可能参与ＰＶＮ对ＩＧＰ的作用，且迷走神经背核可能是调节途径的重要结构之一。

Investigation on Overturning PVN Decreasing IGP Effect After Destroying DMV

The effect of electrical stimulation of PVN on intragastric pressure (IGP) was examined on 38 Spragne-Dawled rats anaesthetized with urethane. The results were as follows: (1) stimulation of PVN could induce an obveous decrease of IGP. (2) This effect was blocked partially by atropine icv. 5 rats (5/13) showed the phasic contraction of stomach significantly. (3) After bilateral destruction of dorsa motor nucleus of vagus, the effect of stimulation of PVN was overturned and IGP increased obviously. 8 rats (8/12) were found the obvious phasic contracton of stomach. In view of the present investigation, it is suggested that (1) in CNS, cholinergic fibres are invlved in the effect of stimulation of PVN on reducing IGP; (2) the action of dorsa motor nucleus of vagus is also probably involved in this effect of PVN stimulation.