膈下迷走神经切断对条件性味觉厌恶大鼠脑内Fos表达的影响

Effects of subdiaplragnmtic vagotomy on brain Fos expression of conditioned taste aversion rats

目的：探讨膈下迷走神经切断与条件性味觉厌恶（CTA）对大鼠脑内Fos表达的影响及其交互作用。方法：将雄性SD大鼠随机分为CTA迷走神经切断组、CTA假手术组、正常迷走神经切断组和正常假手术组，对各组大鼠施予口腔插管手术，向2个CTA组大鼠口腔内给以蔗糖溶液联合腹腔注射使其获得CTA，于膈下切断迷走神经，然后进行免疫组织化学反应。结果：建立CTA使中缝苍白核（RPa）内Fos表达水平升高，且与切断迷走神经无关；建立CTA和迷走神经切断均可使孤束核内侧部（SolM）Fos表达水平升高；迷走神经切断使臂旁核中央外侧亚核（cls）内Fos表达水平升高，但与CTA无关；CTA与迷走神经切断对SolM和cls内Fos表达水平存在交互作用，迷走神经切断使对照组大鼠的Fos表达水平升高，但对获得CTA大鼠无影响。结论：大鼠获得CTA后，条件性味觉刺激可诱导RPa和SolM内Fos表达水平升高，且不依赖于迷走神经传人。

Objective： To explore effects between subdiaphragmatic vagotomy and conditioned taste aversion （CTA） on Fos expression in the brain of rats and their interaction. Mettunfs： With 2 X 2 factorial design, twenty SD male rats were random- ly divided into CTA-vagotomy, CTA-sham, control-vagotomy and control-sham groups. All rats were performed oral intu- bation surgery. The rats in two CTA groups were perfused with sucrose solution into oral cavity pairing with intraperitone- ally injected LiCI to establish CTA and vagotomy, and then immunohistochemical method was used to visualize Fos expres- sion. Results： The Fos expression in raphe pallidus （RPa） of rats with CTA was more than that of rats without CTA, which was independent of vagotomy. The Fos expression in medial part of solitary tract nucleus （SolM） was increased by both CTA and vagotomy. The Fos expression in central lateral subnucleus of PBN （cls） of the rats with vagotomy was more than that of the rats without vagotomy, which was independent of CTA. There was an interaction between CTA and vagotomy for the Fos expression in SolM and cls, and the Fos expression was increased by vagotomy in control rats but not in CTA rats. Conclusion： After rats obtain CTA, conditioned taste stimulus can increase the Fos expression in RPa and SolM, which is independent of afferent informations from the vagus nerve.