Research Service, San Francisco Veterans Affairs Health Care Center, 4150 Clement Street, San Francisco, CA 94121, USA; University of California San Francisco, 505 Parnassus Ave, San Francisco, CA 94143, USA.
Research Service, San Diego Veterans Affairs Health Care Center, USA; University of California San Diego, La Jolla, CA 92093, USA.
Brain Res. 2023 Apr 15;1805:148268. doi: 10.1016/j.brainres.2023.148268. Epub 2023 Feb 6.
Molecular mechanisms of the interaction between opioidergic and dopaminergic processing during pain-related experiences in the human brain are still incompletely understood. This is partially due to the invasive nature of the available techniques to visualize and measure metabolic activity. Positron Emission Tomography (PET) radioligand studies using radioactive substances are still the only available modality to date that allows for the investigation of the molecular mechanisms in the human brain. The most commonly studied PET radiotracers are [C]-carfentanil (CFN) and [C]- or [F]-diprenorphine (DPN), which bind to opioid receptors, and [C]-raclopride (RAC) and [F]-fallypride (FAL) tracers, which bind to dopamine receptors. The current meta-analysis examines pain-related studies that used aforementioned opioid and dopamine radioligands in an effort to consolidate the available data into the most likely activated regions. Our primary goal was to identify regions of shared opioid/dopamine neurotransmission during pain-related experiences using within-subject approach. Seed-based d Mapping (SDM) analysis of previously published voxel coordinate data showed that opioidergic activations were strongest in the bilateral caudate, thalamus, right putamen, cingulate gyrus, midbrain, inferior frontal gyrus, and left superior temporal gyrus. The dopaminergic studies showed that the bilateral caudate, thalamus, right putamen, cingulate gyrus, and left putamen had the highest activations. We were able to see a clear overlap between opioid and dopamine activations in a majority of the regions during pain-related experiences, though there were some unique areas of dopaminergic activation such as the left putamen. Regions unique to opioidergic activation included the midbrain, inferior frontal gyrus, and left superior temporal gyrus. Here we provide initial evidence for the functional overlap between opioidergic and dopaminergic processing during aversive states in humans.
在人类大脑与疼痛相关的体验中，阿片能和多巴胺能加工之间相互作用的分子机制仍不完全清楚。这部分是由于现有的可视化和测量代谢活性的技术具有侵入性。使用放射性物质的正电子发射断层扫描（PET）放射性配体研究仍然是迄今为止唯一可用的方式，可以研究人类大脑中的分子机制。最常研究的 PET 放射性示踪剂是 [C]-卡芬太尼（CFN）和 [C]-或 [F]-二苯并庚诺啡（DPN），它们与阿片受体结合，以及 [C]-raclopride（RAC）和 [F]-fallypride（FAL）示踪剂，它们与多巴胺受体结合。目前的荟萃分析检查了使用上述阿片类和多巴胺放射性配体的与疼痛相关的研究，努力将可用数据整合到最有可能被激活的区域中。我们的主要目标是使用基于个体的方法确定与疼痛相关的体验中共享阿片类/多巴胺神经传递的区域。以前发表的体素坐标数据的基于种子的 d 映射（SDM）分析表明，阿片能激活在双侧尾状核、丘脑、右侧壳核、扣带回、中脑、下额回和左侧颞上回最强。多巴胺研究表明，双侧尾状核、丘脑、右侧壳核、扣带回和左侧壳核的激活程度最高。我们能够看到在与疼痛相关的体验中，大多数区域的阿片能和多巴胺能激活之间存在明显的重叠，尽管多巴胺能激活有一些独特的区域，如左侧壳核。阿片能激活特有的区域包括中脑、下额回和左侧颞上回。在这里，我们为人类在痛苦状态下阿片能和多巴胺能加工之间的功能重叠提供了初步证据。
