Effect of ginsenoside-Rg2 on learning and memory of vascular dementiarats

Abstract

Abstract: AIM: To investigate the effect of ginsenoside-Rg2 on learning and memory of vascular dementia rats and its underlying mechanisms, especially the expression of NMDA AMPA receptors. METHODS: Vascular dementia(VD)of rat was induced by permanent occlusion of bilateral common carotid arteries(2OV).The rats were given different doses of ginsenoside-Rg2(2.5, 5.0, 10.0 mg kg)as while as operation. The spontaneous movement and the delayed non-matching-to-position task(DNMPT)in the water maze were used to examine the behavior changes on learning and memory;the mRNA of four different subtypes of NMDA AMPA receptors, including NR1 、 NR2A 、NR2B and GluR2 in hippocampus were determined by the RT-PCR method. RESULTS: The spontaneous movement and spatial learning and memory of VD rats were all decreased.After ginsenoside-Rg2 administration, the spontaneous movement and the spatial learning andmemory were improved;the latency of information swim(IS)and choice swim(CS)decreased, and choice accuration in choice swim increased.The expression of NR1 mRNA was enhanced while NR2A, NR2B and GluR2 were attenuated in hippocampus of VD rats.These pathological changes could be reversed by treatment with ginsenoside-Rg2. CONCLUSION: Ginsenoside-Rg2 can patently improve the spatial learning andmemory of VD rats.The mechanism may be related to the regulation of ginsenoside-Rg2 on the expression of NMDA AMPA receptors in hippocampus.

Key words: vascular dementia, ginsenoside-Rg2, water maze, learning and memory

CLC Number:

R965.2

ZHANG Li, PAN Zhi-yuan, JIN Yi, LONG Chao-liang, WANG Hai. Effect of ginsenoside-Rg2 on learning and memory of vascular dementiarats[J]. Chinese Journal of Clinical Pharmacology and Therapeutics, 2008, 13(3): 276-282.

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