Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Department of Physiology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran.
Neurosci Lett. 2022 Mar 23;774:136519. doi: 10.1016/j.neulet.2022.136519. Epub 2022 Feb 11.
In the present study, to evaluate the role of the basolateral amygdala (BLA) in morphine addiction, the BLA was stimulated electrically, or inactivated temporarily using lidocaine. The electrical stimulation (ES) was delivered to BLA with low or high intensities (LI or HI: 25 or 150 µA, respectively), and five minutes before morphine administration with effective or ineffective doses, lidocaine was microinjected into the BLA. Using a 5-day conditioned place preference (CPP) paradigm, the dependence on morphine was evaluated. The results showed that LI-ES of BLA induced CPP in both the acquisition and expression phases, in the control and the ineffective dose of morphine groups. HI-ES had no effect on CPP acquisition but induced aversion in the expression, with both effective and ineffective doses of morphine. Inactivation of BLA using lidocaine, inhibited morphine-induced CPP in both acquisition and expression phases. The results of the present study indicate the prominent role of BLA in morphine addiction and dependence. Considering the contradictory results of different intensities of ES, it can be inferred that there are different neural circuits in this area of the brain, in relation to the reward responses.
在本研究中，为了评估外侧杏仁核（BLA）在吗啡成瘾中的作用，我们对 BLA 进行了电刺激或使用利多卡因进行暂时失活。电刺激（ES）以低强度（LI：25 µA）或高强度（HI：150 µA）施加于 BLA，并且在给予有效或无效剂量的吗啡之前五分钟，将利多卡因微注射到 BLA 中。使用 5 天条件性位置偏爱（CPP）范式评估对吗啡的依赖。结果表明，BLA 的 LI-ES 在获得和表达阶段均诱导了控制组和吗啡无效剂量组的 CPP。HI-ES 对 CPP 的获得没有影响，但对表达阶段产生了厌恶，同时对有效和无效剂量的吗啡均产生了这种作用。使用利多卡因失活 BLA 抑制了吗啡在获得和表达阶段引起的 CPP。本研究的结果表明 BLA 在吗啡成瘾和依赖中起重要作用。考虑到 ES 不同强度的结果存在差异，可以推断出与奖励反应有关的大脑这一区域存在不同的神经回路。
