Mimami Kouichiro
Department of Anesthesiology, University of Occupational and Environmental Health, Kitakyushu 807 8555.
Masui. 2005 Nov;54(11):1224-33.
Tramadol [(1R, 2R) and (1S, 2S)-2-dimethyl-amino-methyl-1-(3-methoxyphenyl) -cyclohexanol hydrochloride] has been used clinically. It binds to micro-opioid receptors with lower affinity than morphine, which suggests that the antinociceptive action of tramadol may not be due to opioid receptor binding. Several lines of evidence have shown that tramadol inhibits the reuptake of monoamines, as do antidepressant drugs such as desipramine. Tramadol inhibits the reuptake of NE and serotonin. The mechanisms of action of tramadol have not been well understood. Recently, some evidences in the mechanisms of action of tramadol have been published. Tramadol inhibits the muscarinic receptor, serotonin receptor, and nicotinic acetylcholine receptor ion-channel, suggesting these receptors might be related to the mechanisms of action of tramadol. In this review, the mechanisms of action of tramadol were reviewed form these findings. Tramadol does not alter renal blood flow (RBF) in normal rats. This suggests that tramadol would be a safe analgesic maintaining RBF during the postoperative period. It would be necessary to study the effects of tramadol on orphan G-ptotein coupled receptor which is related to the pain.
曲马多[（1R，2R）和（1S，2S）-2-二甲基氨基甲基-1-（3-甲氧基苯基）-环己醇盐酸盐]已在临床上使用。它与微阿片受体结合的亲和力比吗啡低，这表明曲马多的抗伤害感受作用可能不是由于与阿片受体结合所致。几条证据表明，曲马多像地昔帕明等抗抑郁药一样，能抑制单胺的再摄取。曲马多抑制去甲肾上腺素（NE）和5-羟色胺的再摄取。曲马多的作用机制尚未完全明了。最近，已发表了一些关于曲马多作用机制的证据。曲马多抑制毒蕈碱受体、5-羟色胺受体和烟碱型乙酰胆碱受体离子通道，提示这些受体可能与曲马多的作用机制有关。在这篇综述中，根据这些发现对曲马多的作用机制进行了综述。曲马多不改变正常大鼠的肾血流量（RBF）。这表明曲马多在术后期间将是一种维持肾血流量的安全镇痛药。有必要研究曲马多对与疼痛相关的孤儿G蛋白偶联受体的影响。
