Objective:
Based on the progress in Integripetal Rhodiola Herb (IRH) Pharmacologicalresearch and pathogenesis of Alzheimer’s disease (AD)，we selected Hydergine as the control andaimed to explore the possible mechanisms of Chinese medicine IRH in Model Rats with AD byobserving the behavior changes of rat and detecting the expression level of brain tissuemonoamine oxidase (MAO)，the PSD-95 of hippocampus and shank-1 protein，which mayprovide the reference for traditional Chinese medicine treatment of AD.Methods (1) Making models: 5-month-old healthy male Wistar rats were taken a series of processing to become the AD rats models，which including intraperitoneal injection ofD-galactose，the gavage of ALCL3and disposable injection of Scopolamine.
Grouping:
The ratmodels were devided into three groups，the IRH group (Chinese medicine group)，the controlgroup of Hydergine (Western medicine group)，the control group of model（model group）.Besides，the blank control group was also set. (3) Dose：Traditional Chinese medicine group wasgiven irrigation stomach with Rhodiola crude drug 5g / (kg d) while the western medicinegroup was given hydergine by 1 mg / (kg d) . The distilled water were used in the blank controlgroup and model group according to the dose of 10mL/(kg d). The treatment lasted 4 weeks.(4)Index measurement: morris water maze learning，which including the spatial probe test andplace navigation test，was used to evaluate the rat behavior.
The MAO activity in rat braintissue was detected by biochemical assay. The levels of PSD-95 and shank-1 protein in rathippocampus were measured by immunohistochemical method.Results (1)The results of morris water maze learning: In place navigation test，the escapelatency of different time points in rats was significantly different(P<0.01). As the time goes by，the escape latency became more and more shorter. Compared with blank control groups，theescape latency in model groups was much longer(P<0.01). In Chinese medicine group andWestern medicine group，the escape latency was significantly shorten compared to model group(P<0.01，P<0.01，respectively).
The escape latency was not show different between Chinesemedicine group and Western medicine group(P>0.05). In spatial probe test，compared withmodel groups，the dwell time of purpose of quadrant，residence time of the active zone，dwelltime of the platform in others group were significantly longer (P<0.01).The difference was notexisted between Chinese medicine group and Western medicine group(P>0.05).(2) The testing ofMAO activity: The MAO activity in model group was much elevated compared to blank control group(P<0.01). After the treatment，the MAO activity in Chinese medicine and Westernmedicine groups was obviously decreased (P<0.01)，however the difference was not observedbetween Chinese medicine group and Western medicine group(P>0.05). (3)
The detecting ofproteins related to hippocampal synapses:
The levels of PSD-95 and shank-1 protein wereobviously decreased in model group(P<0.01). Compared with model group，the level of PSD-95and shank-1 protein were obviously increased in Chinese medicine group(P<0.01).However，the obvious difference was disappeared when comparing to Western medicine group(P>0.05).
Conclusion:
The AD rats models which made by intraperitoneal injection ofD-galactose，the gavage of ALCL3and disposable injection Scopolamine，can can bettersimulate the AD patients with pathologic physiology and behavior，and it is an ideal AD model.(2)IRH could improve the cognitive dysfunction of AD model rat，and then improving the abilityof learning and memory.(3) IRH may inhabit the MAO activity of brain tissue in AD rat，strengthen pair of DA、NE and other monoamine neurotransmitters in the regulation，therebydelaying the aging of nervous system，improving the ability of learning and memory in ADmodel rat. (4) The treatment of AD model rat by IRH may be associated with upregulation ofhippocampal area PSD-95, shank-1protein expression, regulation of LTP and LTD, affectssynaptic plasticity, and improve the ability of learning and memory of rats related.