ABSTRACT
There are many similarities between memory impairment in patients suffering from Alzheimer and animals treated by Cannabinoids. The agonists of Cannabinoid receptors affect on a variety of memories and leanings. The present study aims to investigate the role of alpha-1-adrenergic receptors in central region of amygdala in state-dependent learning induced by WIN55,212-2 [cannabinoid agonist] in rats. Cannulae placement was performed bilaterally in the central amygdala region of male rats. The rats were trained in the avoidance learning apparatus [step-down model]. 24 hours after training, the memory was tested by measuring the lag time for stepping down the platform. Injection of WIN55, 212-2 intra central amygdala [dose-dependent, 0.25, 0.5 micro g/rat] post-training reduced lag time/latency for stepping down. Injection induced amnesia was reversed by pre-test administration of the same dose of WIN55, 212-2. It is called state-dependent learning. Pre-test intra-central injection of alpha-1-adrenoceptor agonist, Phenylephrine [0.5, 0.25 micro g/rat] improved post-training WIN55, 212-2 [0.5 micro g/rat] intra central injection induced retrieval impairment. But intra injection of Prazosin [0.5 micro g/rat] 2 minutes before injection of WIN55, 212-2 [0.5 micro g/rat] on the testing day inhibited WIN55, 212-2 state-dependent learning. The results suggest that alpha-1-adrenergic receptors in central region of amygdala are involved in learning which dependent on the state induced by WIN55, 212-2