Chen Jie, Varga Angelika, Selvarajah Srikumaran, Jenes Agnes, Dienes Beatrix, Sousa-Valente Joao, Kulik Akos, Veress Gabor, Brain Susan D, Baker David, Urban Laszlo, Mackie Ken, Nagy Istvan
Section of Anaesthetics, Pain Medicine and Intensive Care, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Chelsea and Westminster Hospital, 369 Fulham Road, London, SW10 9NH, UK.
Department of Anaesthesiology, Southwest Hospital, Third Military Medical University, Gaotanyan 19 Street, Shapingba, Chongqing 400038, P. R. China.
Sci Rep. 2016 Sep 22;6:33307. doi: 10.1038/srep33307.
The cannabinoid type 1 (CB1) receptor and the capsaicin receptor (TRPV1) exhibit co-expression and complex, but largely unknown, functional interactions in a sub-population of primary sensory neurons (PSN). We report that PSN co-expressing CB1 receptor and TRPV1 form two distinct sub-populations based on their pharmacological properties, which could be due to the distribution pattern of the two receptors. Pharmacologically, neurons respond either only to capsaicin (COR neurons) or to both capsaicin and the endogenous TRPV1 and CB1 receptor ligand anandamide (ACR neurons). Blocking or deleting the CB1 receptor only reduces both anandamide- and capsaicin-evoked responses in ACR neurons. Deleting the CB1 receptor also reduces the proportion of ACR neurons without any effect on the overall number of capsaicin-responding cells. Regarding the distribution pattern of the two receptors, neurons express CB1 and TRPV1 receptors either isolated in low densities or in close proximity with medium/high densities. We suggest that spatial distribution of the CB1 receptor and TRPV1 contributes to the complexity of their functional interaction.
1型大麻素（CB1）受体和辣椒素受体（TRPV1）在初级感觉神经元（PSN）的一个亚群中共同表达，并且存在复杂但很大程度上未知的功能相互作用。我们报告说，共表达CB1受体和TRPV1的PSN根据其药理学特性形成两个不同的亚群，这可能归因于这两种受体的分布模式。从药理学角度来看，神经元要么仅对辣椒素产生反应（COR神经元），要么对辣椒素以及内源性TRPV1和CB1受体配体花生四烯乙醇胺（ACR神经元）均产生反应。阻断或删除CB1受体只会降低ACR神经元中由花生四烯乙醇胺和辣椒素引发的反应。删除CB1受体还会降低ACR神经元的比例，而对辣椒素反应性细胞的总数没有任何影响。关于这两种受体的分布模式，神经元表达CB1和TRPV1受体时，要么以低密度孤立存在，要么以中/高密度紧密相邻。我们认为，CB1受体和TRPV1的空间分布导致了它们功能相互作用的复杂性。
