Bush David E A, Caparosa Ellen M, Gekker Anna, Ledoux Joseph
W. M. Keck Foundation Laboratory of Neurobiology, Center for Neural Science, New York University New York, NY, USA.
Front Behav Neurosci. 2010 Oct 26;4:154. doi: 10.3389/fnbeh.2010.00154. eCollection 2010.
Beta-adrenergic receptors (βARs) have long been associated with fear disorders and with learning and memory. However, the contribution of these receptors to Pavlovian fear conditioning, a leading behavioral model for studying fear learning and memory, is still poorly understood. The aim of this study was to investigate the involvement of βAR activation in the acquisition, consolidation and expression of fear conditioning. We focused on manipulations of βARs in the lateral nucleus of the amygdala (LA) because of the well-established contribution of this area to fear conditioning. Specifically, we tested the effects of intra-LA microinfusions of the βAR antagonist, propranolol, on learning and memory for auditory Pavlovian fear conditioning in rats. Pre-training propranolol infusions disrupted the initial acquisition, short-term memory (STM), and long-term memory (LTM) for fear conditioning, but infusions immediately after training had no effect. Further, infusion of propranolol prior to testing fear responses did not affect fear memory expression. These findings indicate that amygdala βARs are important for the acquisition but not the consolidation of fear conditioning.
β-肾上腺素能受体（βARs）长期以来一直与恐惧障碍以及学习和记忆相关联。然而，这些受体对巴甫洛夫式恐惧条件反射（一种用于研究恐惧学习和记忆的主要行为模型）的作用仍知之甚少。本研究的目的是调查βAR激活在恐惧条件反射的获得、巩固和表达过程中的参与情况。由于杏仁核外侧核（LA）对恐惧条件反射的作用已得到充分证实，我们重点研究了该区域βARs的调控情况。具体而言，我们测试了向大鼠LA内微量注射βAR拮抗剂普萘洛尔对听觉巴甫洛夫式恐惧条件反射学习和记忆的影响。训练前注射普萘洛尔会干扰恐惧条件反射的初始获得、短期记忆（STM）和长期记忆（LTM），但训练后立即注射则没有效果。此外，在测试恐惧反应之前注射普萘洛尔并不影响恐惧记忆的表达。这些发现表明，杏仁核βARs对恐惧条件反射的获得很重要，但对其巩固并不重要。
