Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Department of Neurology, Institute for Neuroscience, Ghent, Belgium.
Laboratory for Clinical and Experimental Neurophysiology, Neurobiology and Neuropsychology (LCEN3), Ghent University, Department of Neurology, Institute for Neuroscience, Ghent, Belgium.
Brain Stimul. 2015 Jan-Feb;8(1):13-20. doi: 10.1016/j.brs.2014.09.013. Epub 2014 Sep 28.
Depression is the most common psychiatric comorbidity in epilepsy patients. The lack of success with current pharmacological interventions for this patient population, highlights the importance of optimizing non-pharmacological neuromodulatory treatments such as vagus nerve stimulation (VNS). Studies on the antidepressant effect of VNS in epilepsy patients may be confounded by concurrent anti-epileptic drug therapy. To date, studies in epilepsy models overcoming this problem are lacking.
We investigated whether VNS affects anhedonia, a key symptom of major depression, in the kainic acid rat model for temporal lobe epilepsy.
Anhedonia was assessed in kainic acid (KA) and saline (SAL) injected rats using the saccharin preference test (SPT). To exclude differences in taste perception, the quinine aversion test (QAT) was performed. Both groups were randomly subdivided in a VNS and a SHAM group, yielding 4 experimental arms: KA-VNS, KA-SHAM, SAL-VNS and SAL-SHAM. Both VNS groups received 2 weeks of VNS, while the SHAM groups were not stimulated. Thereafter, the SPT and QAT were repeated.
Saccharin preference was significantly reduced in the KA compared to the SAL rats (P < 0.05), without differences in quinine aversion. Two weeks of VNS significantly increased the saccharin preference in the KA-VNS group (P < 0.05), while it had no effect on quinine aversion. No effects of VNS or SHAM were found in the other groups.
The KA rats displayed anhedonia which was significantly decreased by VNS, indicating that this neuromodulatory treatment could likewise diminish depressive symptoms in patients suffering from temporal lobe epilepsy and comorbid depression.
抑郁症是癫痫患者最常见的精神共病。当前针对这一患者群体的药物干预效果不佳，凸显出优化非药物神经调节治疗（如迷走神经刺激术[VNS]）的重要性。VNS 对癫痫患者抗抑郁作用的研究可能因同时进行的抗癫痫药物治疗而受到干扰。迄今为止，缺乏克服这一问题的癫痫模型研究。
我们研究了迷走神经刺激术（VNS）是否会影响海人酸（KA）诱导的颞叶癫痫大鼠模型的快感缺失，这是重性抑郁的一个关键症状。
通过蔗糖偏好测试（SPT）评估 KA 和盐水（SAL）注射大鼠的快感缺失。为排除味觉感知差异，进行了奎宁厌恶测试（QAT）。将两组随机分为 VNS 和假刺激（SHAM）组，产生 4 个实验臂：KA-VNS、KA-SHAM、SAL-VNS 和 SAL-SHAM。两组 VNS 组均接受 2 周的 VNS，而 SHAM 组不进行刺激。然后，重复 SPT 和 QAT。
与 SAL 组相比，KA 组的蔗糖偏好明显降低（P < 0.05），但奎宁厌恶无差异。2 周的 VNS 显著增加了 KA-VNS 组的蔗糖偏好（P < 0.05），而对奎宁厌恶无影响。其他组未发现 VNS 或 SHAM 的影响。
KA 大鼠表现出快感缺失，VNS 显著降低了这种快感缺失，表明这种神经调节治疗同样可以减轻患有颞叶癫痫和伴发抑郁的患者的抑郁症状。
