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 A_2a 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.