This book, with its 16 chapters, documents the present state of knowledge of the adenosine A3 receptor. It covers a wide range of information, including data from studies of theoretical, molecular and cellular pharmacology, signal transduction, integrative physiology, new drug discoveries and clinical applications. It fills an important gap in the literature since no alternative source of such information is currently available. Although the A3 receptor is increasingly being recognized for its increasing number of biological roles throughout the body and many A3 receptor ligands have proven useful in elucidating peripheral and central pathologies, many issues remain unresolved. Moreover, research activity in this field continues to grow exponentially, resulting.