Fredholm B B, Arslan G, Halldner L, Kull B, Schulte G, Wasserman W
Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Naunyn Schmiedebergs Arch Pharmacol. 2000 Nov;362(4-5):364-74. doi: 10.1007/s002100000313.
Four adenosine receptors have been cloned from many mammalian and some non-mammalian species. In each case the translated part of the receptor is encoded by two separate exons. Two separate promoters regulate the A1 receptor expression, and a similar situation may pertain also for the other receptors. The receptors are expressed in a cell and tissue specific manner, even though A1 and A2B receptors are found in many different cell types. Emerging data indicate that the receptor protein is targeted to specific parts of the cell. A1 and A3 receptors activate the Gi family of G proteins, whereas A2A and A2B receptors activate the Gs family. However, other G proteins can also be activated even though the physiological significance of this is unknown. Following the activation of G proteins several cellular effector pathways can be affected. Signaling via adenosine receptors is also known to interact in functionally important ways with signaling initiated via other receptors.
已经从许多哺乳动物和一些非哺乳动物物种中克隆出四种腺苷受体。在每种情况下，受体的翻译部分由两个独立的外显子编码。两个独立的启动子调节A1受体的表达，其他受体可能也存在类似情况。这些受体以细胞和组织特异性的方式表达，尽管在许多不同的细胞类型中都发现了A1和A2B受体。新出现的数据表明，受体蛋白靶向细胞的特定部位。A1和A3受体激活G蛋白的Gi家族，而A2A和A2B受体激活Gs家族。然而，其他G蛋白也可能被激活，尽管其生理意义尚不清楚。G蛋白激活后，几种细胞效应途径可能会受到影响。已知通过腺苷受体的信号传导也会以功能上重要的方式与通过其他受体启动的信号传导相互作用。
