G 偶联蛋白受体 (GPCR) 是药理学和医学的终极避难所，因为超过 40% 的市售药物直接针对这些受体。通过细胞表面表达，它们是细胞与外界沟通的最前沿。随着这种通讯传递者中的代谢物被认为是 GPCR 的配体，它们变得越来越重要。 HCAR1 是乳酸的 GPCR 转运蛋白。它是与 Gαi 偶联的 A 类 GPCR，可减少细胞 cAMP 以及下游 Gβγ 信号传导。它首先被发现可以抑制脂肪分解，最近被发现与多种细胞过程有关，包括神经活动、血管生成、炎症、视力、心血管功能、干细胞增殖，并参与促进不同病症（例如癌症）的发病机制。除了来自质膜的信号传导之外，HCAR1 还表现出核定位，其中具有不同的定位偏向活性。尽管 HCAR1 的不同功能正在被发现，但其细胞和分子机制仍不清楚。在这里，我们对 HCAR1 进行了全面的回顾，其中涵盖了有关该主题的文献，并讨论了它在各种生物现象中的重要性和相关性。

G-coupled protein receptors (GPCR) are the ultimate refuge of pharmacology and medicine as more than 40% of all marketed drugs are directly targeting these receptors. Through cell surface expression, they are the forefront of cellular communication with the outside world. Metabolites amongst the conveyors of this communication are becoming more prominent with the recognition of them as ligands for GPCRs. HCAR1 is a GPCR conveyor of lactate. It is a class A GPCR coupled to Gαi which reduces cellular cAMP along with the downstream Gβγ signaling. It was first found to inhibit lipolysis, and lately has been implicated in diverse cellular processes, including neural activities, angiogenesis, inflammation, vision, cardiovascular function, stem cell proliferation, and involved in promoting pathogenesis for different conditions, such as cancer. Other than signaling from the plasma membrane, HCAR1 shows nuclear localization with different location-biased activities therein. Although different functions for HCAR1 are being discovered, its cell and molecular mechanisms are yet ill understood. Here we provide a comprehensive review on HCAR1, which covers the literature on the subject, and discussing its importance and relevance in various biological phenomena.