ADENOSINE RECEPTOR LIGANDS - DIFFERENCES WITH ACUTE VERSUS CHRONIC TREATMENT

Adenosine receptors have been the target of intense research with resp ect to potential use of selective ligands in a variety of therapeutic areas. Caffeine and theophylline are adenosine receptor antagonists, a nd over the past three decades a wide range of selective agonists and antagonists for adenosine receptor subtypes have been developed. A com plication to the therapeutic use of adenosine receptor ligands is the observation that the effects of acute administration of a particular l igand can be diametrically opposite to the chronic effects of the same ligand. This 'effect inversion' is discussed here by Ken Jacobson and colleagues, and has been observed for effects on cognitive processes, seizures and ischaemic damage.