ADENOSINE RECEPTORS INVOLVED IN THE BRONCHOCONSTRICTOR EFFECT OF ADENOSINE

Adenosine may play a role in the airflow obstruction in asthma and chr onic obstructive pulmonary disease. Although the mechanism of adenosin e-induced bronchoconstriction has been well explored, little is known about the identity of adenosine-receptors involved. Studies on rabbit and rat airways suggest that multiple receptors (A(1), A(2B), and A(3) receptors) may be involved in the bronchoconstrictor of adenosine. Ma st cell mediators contribute to adenosine-induced bronchoconstriction. Studies on isolated mast cell lines have revealed the presence of A(2 B) and A(3) receptors. The in vitro contraction of human bronchi is me diated by an adenosine receptor (A(1) or A(2)?). A(2) receptors have b een demonstrated by ligand binding in human peripheral airways. The pr esence of the A(3) receptor has been shown by in situ hybridization in eosinophils and mesenchymal tissue. The development of potent and spe cific adenosine receptor agonists and antagonists will increase our kn owledge on this issue and may offer new therapeutic approaches to obst ructive airway diseases. (C) 1997 Wiley-Liss, Inc.