Overview
- Peptide (C)KKVSASSGDPQKYYGKE, corresponding to amino acid residues 213-229 of human A1AR (Accession P30542). 3rd intracellular loop.
- Rat brain and kidney lysates (1:200).
- Western blot analysis of rat brain (lanes 1, 3) and rat kidney (lanes 2, 4) lysates:1,2. Anti-Adenosine A1 Receptor Antibody (#AAR-006), (1:200).
3,4. Anti-Adenosine A1 Receptor Antibody, preincubated with Adenosine A1 Receptor Blocking Peptide (#BLP-AR006).
- Rat cortex and medial septum frozen sections.
- Rat primary dorsal root ganglion (DRG) culture.
Adenosine is an endogenous nucleoside generated locally in tissues under conditions of hypoxia, ischemia, or inflammation. It modulates a variety of physiological functions in many tissues including the brain and heart.1,2 Adenosine exerts its actions via four specific adenosine receptors (also named P1 purinergic receptors): Adenosine A1 Receptor (A1AR), Adenosine A2A Receptor (A2AAR), Adenosine A2B Receptor (A2BAR), and Adenosine A3 Receptor (A3AR). All are integral membrane proteins and are members of the G protein-coupled receptor superfamily. They share a common structure of seven putative transmembrane domains, an extracellular amino terminus, a cytoplasmic carboxyl terminus, and a third intracellular loop that is important for binding G proteins.1-3 The adenosine receptors can be distinguished on the basis of their differential selectivity for adenosine analogs.1-3
A1AR is widely distributed and has been well characterized. High expression of A1AR is found in the brain (mainly in the cortex, cerebellum, and hippocampus), dorsal horn of the spinal cord, adrenal gland, and atria, and to a lower extent in several other tissues including adipose tissue, the colon, and kidney.2,4
A1AR modulates the activity of several ion channels. Activation of A1AR (by adenosine, its major agonist) inhibits N-type Ca2+ channels via a voltage-dependent, pertussis toxin (PTX)-sensitive pathway in neurons of the rat major pelvic ganglia (MPG).5
Since A1AR is the most prominent adenosine receptor in adipocytes, it has become a natural target for research on obesity, which is a major health problem.6,7 A possible role in cell proliferation and carcinogenesis has also been suggested for A1AR.8-10