RESUMO
<p><b>OBJECTIVE</b>To study the effect of the Qingxin Kaiqiao fang on learning and memory ability and shape hippocampal nerve cells in Alzheimer disease (AD).</p><p><b>METHOD</b>One handred and fifty mice were divid into five groups: blank group, model group, two groups of treatment by Qingxin Kaiqiao fang (14.82, 7.41 g x kg(-1)), piracetan comparison group (0.42 g x kg(-1)). The model group was orally given AlCl3 (200 mg x kg(-1)) every day. For Qingxin Kaiqiaofang and piracetan groups, AlCl3 treatment was given for 6 days at the beginning, followed by giving orally AlCl3 in the morning and drug in the afternoon for 8 weeks. Then, learning and memory aility, the contents of nitric oxide (NO), NO synthase (NOS) and acetylcholinesterase (AchE) in brain, and morphology of hippocampal nerve cells were investigated.</p><p><b>RESULT</b>Learning and memory ability of Qingxin Kaiqiaofang groups was improved, compared with comparison group; the difference was significant (P < 0.05, P < 0.01). The drug could prevent hippocampal nerve cells from damaged obviously. The contents of NO, NOS and AchE in mice of treatment groups were lower than those of comparison group; the difference was significant (P < 0.05, P < 0.01).</p><p><b>CONCLUSION</b>Qingxin Kaiqiaofang can improve learning and memory ability of AD mice, prote chippocampal nerve cells, and treat Alzheimer disease.</p>