Both aging and age-associated neurodegenerative diseases are related with various degrees of behavioral impairments, and among the prime candidates responsible for producing the neuronal changes mediating these behavioral deficits, appear to be free radicals and the oxidative agents which they generate. Free radicals such as vit. E may be important factors in maintaining neuronal integrity and preventing cell death. In this research, effects of vit. E on memory retention was evaluated. vit. E (10, 20, and 50 ?g/rat) and prazocin (0.1, 1, and 0.5 ?g/rat) were injected intracerebroventricularly. The effect of drugs on memory retention was studied by passive avoidance task and time of step-through latency (STL) was measured. The results indicated that vit. E (50 ?g/rat) increases and prazocin (0.5, and 1 ?g/rat) decreases memory retention in a dose - dependent manner. The pretreatment of prazocin (0.1, 0.5, and 1 ?g/rat) attenuated increasing response induced by vit. E (50 ?g/rat). The results showed that vit.E may induce its memory retention effects through activation of ?1-adrenoceptors.