Adenosine A2B receptor

The adenosine A2B receptor, also known as ADORA2B, is a G-protein coupled adenosine receptor, and also denotes the human adenosine A2b receptor gene which encodes it.

Mechanism
This integral membrane protein stimulates adenylate cyclase activity in the presence of adenosine. This protein also interacts with netrin-1, which is involved in axon elongation.

Gene
The gene is located near the Smith-Magenis syndrome region on chromosome 17.

Ligands
Research into selective A2B ligands has lagged somewhat behind the development of ligands for the other three adenosine receptor subtypes, but a number of A2B-selective compounds have now been developed,         and research into their potential therapeutic applications is ongoing.

Agonists

 * BAY 60-6583
 * NECA (N-ethylcarboxamidoadenosine)
 * (S)-PHPNECA - high affinity and efficacy at A2B, but poor selectivity over other adenosine receptor subtypes
 * LUF-5835
 * LUF-5845 - partial agonist

Antagonists and inverse agonists

 * Compound 38: antagonist, high affinity and good subtype selectivity
 * ISAM-R56A: non-xanthinic high affinity selective antagonist (Ki: 1.50 nM)
 * ISAM-140: non-xanthinic selective antagonist (Ki = 3.49 nM).
 * ISAM-R324A: Soluble and metabolically stable non-xanthinic selective antagonist (Ki = 6.10 nM).
 * ATL-801
 * CVT-6883
 * MRS-1706
 * MRS-1754
 * OSIP-339,391
 * PSB-603: xanthinic antagonist
 * PSB-0788: xanthinic antagonist
 * PSB-1115: xanthinic antagonist
 * PSB-1901: xanthinic antagonist with picomolar potency