Objective:To investigate the agonist and inhibitor effects of β2-adrenergic receptor(β2-AR) on learning and memory capacities and the level of acetylcholine in hippocampus of Alzheimer’s disease(AD)rats. Methods:Forty healthy male Sprague Dawley rats were randomly and equally divided into 4 groups,ie,saline-injected group,AD group,clenbuterol group and ICI118,551 group. The AD rat model was established by amyloid-β1-40(Aβ1-40) injection into hippocampus. Then the clenbuterol group and ICI118,551 group were peritoneal injected by clenbuterol of 0.5 mg/kg and ICI118,551 of 1 mg/kg respectively for 20 days after they were injected Aβ1-40 injection. The learning and memory ability were determined by Y-maze,and the activity of AChE and ChAT in hippocampus was tested by chemistry method. Nissle staining was used to verify neuron apoptosis. Results:Compared with the AD rats,the learning and memory ability of rats injected with clenbuterol were significantly decreased(P < 0.01),correspondingly,the activity of AChE and ChAT decreased. While in the rats of the ICI118,551 group,both their learning and memory ability and the activity of AChE and ChAT were increased compared with those in the AD rats(P < 0.05). Conclusion:The β2-AR agonist clenbuterol might aggravate the injury induced by Aβ1-40,while the β2-AR selective antagonist ICI 118,551 can improve AD pathological process. These results suggested that the level of acetylcholine in brain tissue may be involved in the possible mechanisms of AD.