Department of Biology Department, Unit 8264, Stetson University, 421 North Woodland Boulevard, DeLand, FL 32723, USA.
Chem Senses. 2013 Oct;38(8):705-17. doi: 10.1093/chemse/bjt039. Epub 2013 Aug 26.
Projections from the central amygdala (CeA) and lateral hypothalamus (LH) modulate the activity of gustatory brainstem neurons, however, the role of these projections in gustatory behaviors is unclear. The goal of the current study was to determine the effects of electrical stimulation of the CeA or LH on unconditioned taste reactivity (TR) behaviors in response to intra-oral infusion of tastants. In conscious rats, electrical stimulation of the CeA or LH was delivered with and without simultaneous intra-oral infusion of taste solutions via an intra-oral cannula. Immunohistochemistry for the Fos protein was used to identify neurons in the gustatory brainstem activated by the electrical and/or intra-oral stimulation. In the absence of intra-oral infusion of a tastant, electrical stimulation of either the CeA or the LH increased the number of ingestive, but not aversive, TR behaviors performed. During intra-oral infusions of taste solutions, CeA stimulation tended to increase aversive behaviors whereas LH stimulation dramatically reduced the number of aversive responses to quinine hydrochloride (QHCl). These data indicate that projections from the CeA and LH alter TR behaviors. A few of the behavioral effects were accompanied by changes in the number of Fos-immunoreactive neurons in the gustatory brainstem, suggesting a possible anatomical substrate for these effects.
杏仁中央核（CeA）和外侧下丘脑（LH）的投射调节味觉脑干神经元的活动，然而，这些投射在味觉行为中的作用尚不清楚。本研究的目的是确定 CeA 或 LH 的电刺激对口腔内灌注味觉刺激物时非条件味觉反应（TR）行为的影响。在清醒大鼠中，通过口腔内套管同时进行口腔内味觉溶液灌注和 CeA 或 LH 的电刺激。用 Fos 蛋白免疫组织化学来鉴定电刺激和/或口腔刺激激活的味觉脑干神经元。在没有口腔内灌注味觉刺激物的情况下，CeA 或 LH 的电刺激增加了摄取性但不是厌恶性 TR 行为的数量。在口腔内灌注味觉溶液期间，CeA 刺激往往会增加厌恶行为，而 LH 刺激则大大减少了对盐酸奎宁（QHCl）的厌恶反应次数。这些数据表明，CeA 和 LH 的投射改变了 TR 行为。一些行为效应伴随着味觉脑干中 Fos-免疫反应性神经元数量的变化，这表明这些效应可能有解剖学基础。
