The search for cannabinoid receptors other than CB1R and CB2R has been ongoing for over a decade. A number of orphan receptors have been proposed as potential cannabinoid receptors primarily based on phylogenic arguments and reactivity towards known endocannabinoids and phytocannabinoids. Seven putative cannabinoid receptors are described and discussed, and evidence for and against their inclusion in this category are presented.

中文翻译：

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内源性大麻素信号通路：超越 CB1R 和 CB2R

对 CB1R 和 CB2R 之外的大麻素受体的研究已经持续了十多年。主要基于系统发育论点以及对已知内源性大麻素和植物大麻素的反应性，许多孤儿受体被提议作为潜在的大麻素受体。描述和讨论了七种假定的大麻素受体，并提出了支持和反对将其纳入这一类别的证据。