Fatahi Zahra, Zibaii Mohammad Ismail, Haghparast Abbas
Neuroscience Research Center, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran.
Behav Brain Res. 2017 Sep 29;335:19-25. doi: 10.1016/j.bbr.2017.08.008. Epub 2017 Aug 7.
The basolateral amygdala (BLA) plays a critical role in the neural circuitry of stress and mediates the effects of stress on memory related processes. Moreover, this area has an important role in drug-seeking and relapse of approach behavior to drug-associated cues. Therefore, in the present study, we aimed to investigate the effects of acute and subchronic stress in saline- and/or morphine-treated rats in conditioned place preference paradigm on the neural activity in the BLA. Male Wistar rats were divided into two saline- and morphine-treated supergroups. Each supergroup contained control, acute stress (AS) and subchronic stress (SS) groups. In all of the groups, conditioned place preference paradigm was done and thereinafter the spontaneous firing activity was recorded by in vivo single unit recording for 20min. Results showed that in saline-and/or morphine-treated animals, both AS and SS increased neural activity of projection neurons and this increase in morphine-treated animals was more considerable than that of saline-treated animals. Besides, firing rate of interneurons in both supergroups decreased during AS and SS. Decrease of interneurons activity after application of SS in morphine-treated animals was more than that of saline-treated animals. These finding revealed that both of AS and SS increased firing rate of projection neurons but decreased neural activity of interneurons in the BLA. However, effect of AS and SS on the firing rate of BLA neurons in morphine-treated animals was more remarkable than that of saline-treated animals.
基底外侧杏仁核（BLA）在应激神经回路中起关键作用，并介导应激对记忆相关过程的影响。此外，该区域在寻求药物和对药物相关线索的趋近行为复发中具有重要作用。因此，在本研究中，我们旨在研究在条件性位置偏爱范式下，急性和亚慢性应激对生理盐水和/或吗啡处理的大鼠BLA神经活动的影响。雄性Wistar大鼠被分为生理盐水和吗啡处理的两个超级组。每个超级组包含对照组、急性应激（AS）组和亚慢性应激（SS）组。在所有组中，均进行条件性位置偏爱范式，然后通过体内单单位记录20分钟来记录自发放电活动。结果表明，在生理盐水和/或吗啡处理的动物中，AS和SS均增加了投射神经元的神经活动，且吗啡处理动物的这种增加比生理盐水处理动物更显著。此外，在AS和SS期间，两个超级组中间神经元的放电率均降低。在吗啡处理的动物中，应用SS后中间神经元活动的降低比生理盐水处理的动物更明显。这些发现表明，AS和SS均增加了投射神经元的放电率，但降低了BLA中间神经元的神经活动。然而，AS和SS对吗啡处理动物中BLA神经元放电率的影响比生理盐水处理动物更显著。
