中国科学院心理健康重点实验室知识库

抑郁症是一种复杂的情绪疾病,能够影响多种感知觉模态的加工,其中也包括对疼痛感知的调节.临床研究发现,抑郁状态能够提高疼痛感受,且抑郁患者抱怨疼痛的频率显著增高.抑郁症和慢性疼痛都是难以治愈的疾病,两种疾病的共病,不仅给患者带来了极大的痛苦,还给社会带来了沉重的医疗负担.然而,在一些实验室研究中却观察到了矛盾的现象,抑郁患者常常表现出对实验室疼痛刺激的敏感性降低,对热刺激、电刺激或机械刺激的反应减弱.这种矛盾的存在表明抑郁症对于疼痛感知的调节可能较为复杂.动物实验中也存在一些矛盾的结果.有些研究发现,抑郁情绪能够增强疼痛,但是还有些研究却证实了抑郁动物对于疼痛刺激的敏感性降低,这种多样性的调节作用可能源自于抑郁模型的差异以及疼痛类型的不同.本实验室自2010年起进行了一系列的动物研究,发现抑郁情绪能够增强福尔马林持续痛,同时减弱对于某些诱发痛刺激的反应,这些结果提示抑郁情绪对于疼痛的调节作用会因疼痛模式的差异而不同.疼痛包括感觉-辨别、情绪-动机以及认知-评价3种维度,抑郁情绪对疼痛的影响可能正是其对于这3种维度的调节作用之和.本综述将对抑郁调节疼痛感知的动物研究进行评述,为深入探索抑郁调节疼痛感知的机制提供参考.

Depression is a complicated affective disorder and the most common cause of disability. Globally, more than 350 million people suffer from depression at present. The patients with depression may have a set of the mental symptoms, including depressed mood, anhedonia and anergia. They may also express irritability, disrupted sleep and/or appetite, poor concentration and even suicidal tendency. Depression is highly comorbid with pain. Studies have proved that nearly 65% patients with depression also suffer from pain, and elevated pain perception has been found in depressed patients. Both depression and chronic pain are incurable diseases. The concurrence of depression and pain not only causes great suffering to the patients, but also brings a heavy medical burden to the society. However, laboratory studies have found bidirectional modulation of depression on pain. Some researchers observed that experimentally-induced negative mood increased self-reported pain in chronic back pain patients, while others reported that subjects with depressive disorders displayed elevated threshold and tolerance when exposed to thermal- and electrical-evoked pain. The intricate relationship between pain and depression has been concerned for many years. Animal models are useful tools to investigate the neuronal mechanisms of the depression and pain comorbidity. As were in human subjects, experiments in animals also yielded contradictory results. Some studies proved enhanced pain perception in depressive-like animals, but some others found that depression could reduce the sensitivity to pain stimulation. There are many kinds of depression models, such as chronic restraint stress, chronic social stress, unpredictable chronic mild stress, olfactory bulbectomy, Wistar-Kyoto rat, and reserpine-induced monoamine depletion. The difference of these models may contribute to the divergent effects of depression on pain. Since 2010, our laboratory has conducted a series studies about the comorbidity of depression and pain. Using animal models of unpredictable chronic mild stress and olfactory bulbectomy, our previous work demonstrated that depression could enhance the persistent inflammatory pain response but reduce the noxious stimulus-evoked withdrawal behavior in rats. These results supported that another important factor of the divergent effects may be the pain modality. Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage. Researchers have described three dimensions of pain: sensory-discrimination, affective-motivation and cognitive-evaluation. The effects of depression on different pain modalities may be associated with different processing patterns of these three dimensions. In this review, we will discuss the interaction between depression and pain modalities in some animal models. We hope that this review could provide guidance for the future researches about the comorbidities of depression and pain.

国家自然科学基金(31271092,31671140,31500857,31171067,31471061);; 中国科学院心理健康院重点实验室项目(KLMH2016K02,KLMH2014G01)资助