Activation of adenosine A1 receptors in the nucleus accumbens impairs inhibitory avoidance memory

Potent and highly selective adenosine A1 and A2 receptor agonists were bilaterally injected into the nucleus accumbens of mice 10 min prior to inhibitory avoidance training. Retention of the inhibitory avoidance response was assessed 24 h after training. Intra-ACB activation of A1 receptors, but not A2a receptor activation, significantly impaired the performance of mice during the subsequent retention test. Furthermore, the retention deficit produced by activation of A1 receptors was significantly attenuated by pretreating mice with a highly selective A1 receptor antagonist. These findings suggest that endogenous adenosine may modulate information processing in the ventral striatum via adenosine A1 receptors.