Objective: To observe the effect of total glycosides of Acanthopanax senticosus on memory acquisition deficit induced by rapid eye movement sleep deprivation(REMSD)and illustrate the underlying mechanism of long-term potentiation(LTP) and synaptic plasticity. Method: Male SD ratswere used in this study. Rats were deprived of REM sleep by modified multiple platform method (MMPM).The REM sleep loss before learning could result in memory acquisition deficit in rats. Then we investigated the effect of total glycosides of A.senticosus on memory acquisition deficit rats with hexagonal maze paradigm. At last

the population spike (PS)amplitudein the hippocampus (CA1) region of the rats was recordedwith electrophysiological technic in vivo. Result: Compared with control group

the ability of learning and memory as well as PS amplitude obviously descended in model group(P<0.01). Those in two doses of total glycoside of A.senticosus(200

100 mg·kg-1)were enhanced significantly compared with model group(P<0.01 or P<0.05) in a dose-dependent manner. Conclusion: REMSD before learning could cause memory acquisition deficit. Total glycosides of A.senticosus could protect the memory deficitcaused by REMSD. The protective effect may be related to the enhanced synaptic plasticity in the hippocampus CA1 regionof rats.