Stimulant effects of adenosine antagonists on operant behavior: differential actions of selective A2A and A1 antagonists.

Rationale: Adenosine A(2A) antagonists can reverse many of the behavioral effects of dopamine antagonists, including actions on instrumental behavior. However, little is known about the effects of selective adenosine antagonists on operant behavior when these drugs are administered alone.

Objective: The present studies were undertaken to investigate the potential for rate-dependent stimulant effects of both selective and nonselective adenosine antagonists.