The lateral hypothalamus and anterior hypothalamic nucleus differentially contribute to rats' defensive responses in the elevated plus-maze and shock-probe burying tests
- 作者：Rebecca M. Hakvoort Schwerdtfeger ; Janet L. Menard
- 关键词：Defensive behavior ; Anxiety ; Threat stimuli ; Hypothalamus ; Limbic system ; GABA
- 刊名：Physiology and Behavior
- 出版年：2008
- 期刊代码：220_00319384
- 类别：med
- 出版时间：18 March 2008
- 卷：93
- 期：4-5
- 页码：697-705
- 文件大小：522 K
摘要
Lesions or pharmacological inhibition of the lateral septum reduce rats' open-arm avoidance in the elevated plus-maze and their burying behavior in the shock-probe test. The current study examined whether hypothalamic areas that receive direct input from the lateral septum also influence open-arm avoidance and defensive burying. Bilateral infusions of the GABA-A receptor agonist muscimol (20 ng) into the lateral hypothalamus selectively increased rats' open-arm avoidance without affecting shock-probe burying. In contrast, infusions of muscimol into the anterior hypothalamic nucleus suppressed burying without affecting rats' open-arm avoidance. These dissociations suggest that the lateral hypothalamus contributes to the exploration of potentially threatening environments, whereas the anterior hypothalamus influences defensive responses to proximal discrete threat stimuli.