OBJECTIVETo investigate the protection mechanism of prepared Polygonum multiflorum (PPMT) in rat brain with sodium azide (NaN3) perfusion.

METHODRats were divided into six groups: control, model, PPMT, Duxil and PPMT + Duxil groups. The intracerebral microdialysis and high performance liquid chromatography-post column Immobilized enzyme reactor-electrochemical detection were used to continuously measure extracellular acetylcholine (ACh) and choline (Ch) levels in striatum of freely moving awake rats.

RESULTThe extracellular Ach, Ch levels of striatum stayed stable in the control group during the whole observing period, but the ACh levels in the model group were lower significant than that in the control group. The Ach levels of three drug groups were respectively higher significant than that of model group at some time points. While the extracellular Ch level in striatum of the model group increased singnificantly compared with the control group. The Ch levels of the three drug groups were lower significant than that of the model group respectively at certain time points. The effects of PPMT were similar with that of Duxil.

CONCLUSIONThe prepared P. multiflorum can improve the impaired cholinergic nerve function to exert the effects of brain protection by elevating extracellular Ach level and improving uptake of extracellular Ch. It may provide the experimental evidence to support the idea that P. multiflorum could be brain protective drug to treat retrogressive disease such as dementia.