Preventive effect of nicotine on learning and memory functions in Alzheimer rats

Objective To explore the role of nicotine pretreatment on Alzheimer disease (AD). Methods Totally 26 SD rats orally took 5 μg/ml nicotine in 2% sugar solution daily, and then 7 d later, they (nicotine AD group) and other 26 rats (AD group) received the injection of amyloid peptideβ25-35 into their hippocampus to establish AD rat model. Another 8 rats served as normal control. Functions of learning and memory were evaluated by Morris test. Results During the place navigation test, the latency of the nicotine AD group was decreased compared with the AD group, and the percentages of swimming time and swimming distance at the target quadrant were higher than the AD group. Conclusion Nicotine prevents the dysfunction of learning and memory induced by Aβ25-35. The mechanism may be related with neurotransmitter release promoted by nicotine.