Abstract: Abstract: Objective Vascular dementia (VD) is one of the most common forms of dementia with a progressive decline in memory and cognitive function. In the present study, we investigated the effect of dl-3-n-Butylphthalide (dl-NBP) on learning and memory impairment induced by chronic cerebral hypoperfusion in rats. Methods Male Wistar rats fed with high fat were orally administered 40 mg/kg dl-NBP daily for 30days after bilateral permanent occlusion of the common carotid arteries. Morris water maze (MWM）test was employed to assess spatial memory and learning. The LTP induced by high frequency stimulation (HFS) at CA3-CA1 synapses of the hippocampus was recorded for measuring the slope of field excitatory postsynaptic potential (fEPSP). Results The LTP in the CA1 region of the hippocampus was enhanced more obviously in dl-NBP treatment group than that in VD group. The average amplitude of LTP was significantly increased by 120.5± 7.3% in dl-NBP treated group and 108.4±16.9% in VD group compared to those of basal condition, respectively. There was statistical significance between the two groups (P<0.01). The MWM test revealed that there were significant differences between two groups in the acquisition phase and in the retention phase, implying a considerable improvement of spatial memory in VD+dl-NBP group compared with that of VD group. Conclusion The data suggested that dl-NBP had beneficial effect on the spatial learning and memory of VD rats, also suggested the therapeutic potential for cognitive deficits of dementia induced by chronic cerebral hypoperfusion.

Key words: dl-3-n-Butylphthalide (dl-NBP), Vascular dementia (VD), long-term potentiation(LTP), Morris water maze(MWM)