Effect of Yuanzhisan on Learning and Memory Abilities and Food Intake of AD Rats Based on Ghrelin Level of Cerebrointestinal Peptide / 中国实验方剂学杂志

ABSTRACT

Objective:Through the preparation of Alzheimer's disease （AD） rat model， the effect of Yuanzhisan on the expression of Ghrelin was observed， and the possible mechanisms in preventing and treating AD were discussed. Method:A total of 120 SD rats were randomly divided into sham-operated group， model group， donepezil group（1.02 mg·kg-1）， and high， medium and low-dose Yuanzhisan groups （12，6，3 g·kg-1）， with 20 rats in each group， including half male and half female. The rats in sham-operated group were injected with normal saline （NS）， and the rats in other groups were injected with β-amyloid 1-40 （Aβ1-40） in hippocampus to induce the AD rat model. During the 10-week continuous gavage， the food intake of rats in each group was observed and recorded. After the end of gavage， learning and memory abilities of rats were tested by Morris water maze. The whole brain and the gastric body and antrum were collected， the pathologic changes in the CA1 area of hippocampus was assessed by hematoxylin-eosin （HE） staining， and the expression of Ghrelin was detected by immunohistochemistry. Result:Compared with the sham-operated group， the escape latency time of model group rats increased （P<0.01），while times across platform， retention time in effective area and movement distance decreased （P<0.01）. The disorder of neurons， the decrease of the neuronal number， and the pyknosis of nucleus were observed in hippocampal CA1 area. The food intake of male and female rats decreased significantly （P<0.05，P<0.01）. The expression of Ghrelin in hippocampal CA1 area and gastric mucosa decreased significantly （P<0.01）. Compared with the model group， the escape latency time of rats in each treatment group was significantly shortened （P<0.05，P<0.01），whereas times across platform， retention time in effective area and movement distance increased （P<0.05，P<0.01）. The pathologic change was improved markedly， and the daily food intake of rats in high and medium-dose Yuanzhisan groups increased significantly （P<0.05，P<0.01）. The protein expression of Ghrelin in hippocampal CA1 area and gastric mucosa increased significantly in each Yuanzhisan group （P<0.05，P<0.01）. Conclusion:Yuanzhisan can effectively improve the learning and memory abilities of AD rats and increase the daily intake， which may be related to its up-regulation of Ghrelin content in hippocampal CA1 area and gastric mucosa.