Ethanol withdrawal commonly leads to anxiety-related disorder, a central factor toward negative reinforcement leading to relapse. The lateral habenula (LHb), an epithalamic nucleus, has emerged to be critical for both reward and aversion processing. Recent studies have also implicated the hyperactivity of LHb, adding to the emergence of negative emotional states during withdrawal from addictive drugs. Herein, we have studied the effects of glutamate transporter inhibitor (PDC), GluN2B-containing NMDAR antagonist (Ro25-6981), and intracellular calcium chelator (BAPTA-AM) injection in LHb on ethanol withdrawal symptoms. We found that ethanol 4 g/kg 20 % w/v intragastric (i.g.) for 10 days followed by 24 h of withdrawal showed a significant increase in somatic signs characterized by vocalization, shaking, and scratching. It also increased locomotor activity and anxiety-like behavior, collectively showing expression of ethanol withdrawal symptoms. The intra-LHb administration of PDC (0.5 ng) worsened the effect of ethanol withdrawal, whereas Ro25-6981 (2 and 4 ng) and BAPTA-AM (6.5 and 13 ng) significantly reversed ethanol withdrawal-induced behavior evident by a decrease in somatic signs, locomotor activity, and anxiety-like behavior. Further, pretreatment of Ro25-6981 and BAPTA-AM reduced the neuronal loss, whereas PDC increased it compared to the vehicle-treated group, as evidenced by NeuN staining. Altogether, our results suggest that increased glutamate, GluN2B activation, and likely calcium increase indicative of glutamate excitotoxicity-induced neuronal loss in LHb possibly endorse the emergence of ethanol withdrawal symptoms, while their inhibition might help in alleviating the ethanol withdrawal symptoms.

乙醇戒断通常会导致焦虑相关的障碍，这是导致复发的负强化的核心因素。外侧缰核 (LHb) 是一种上丘脑核，对奖励和厌恶处理都至关重要。最近的研究还涉及 LHb 的过度活跃，增加了在戒断成瘾药物期间出现的负面情绪状态。在此，我们研究了 LHb 中谷氨酸转运蛋白抑制剂 (PDC)、含 GluN2B 的 NMDAR 拮抗剂 (Ro25-6981) 和细胞内钙螯合剂 (BAPTA-AM) 注射液对乙醇戒断症状的影响。我们发现，乙醇 4 g/kg 20% w/v 灌胃 (ig) 10 天，然后停药 24 小时，表现出以发声、摇晃和抓挠为特征的躯体体征显着增加。它还增加了运动活动和焦虑样行为，共同表现出乙醇戒断症状。PDC (0.5 ng) 的 LHb 内给药使乙醇戒断效果恶化，而 Ro25-6981 (2 和 4 ng) 和 BAPTA-AM (6.5 和 13 ng) 显着逆转乙醇戒断诱导的行为，明显减少体征、运动活动和焦虑样行为。此外，与载体处理组相比，Ro25-6981 和 BAPTA-AM 的预处理减少了神经元损失，而 PDC 增加了它，如 NeuN 染色所证明的。总而言之，我们的结果表明，谷氨酸、GluN2B 激活和可能的钙增加表明谷氨酸兴奋性毒性诱导的 LHb 神经元损失可能支持乙醇戒断症状的出现，