Study On The Antidepressant Effect And Mechanisms Of Xiaoyao Powder In Olfactory Bulbectomized Depression Rats

Build the olfactory bulbectomized(OB) depression rat model, to study the antidepressant effects and5-HT molecular mechanism of Xiaoyao Powder to the OB depression rat model. Methods:1the depression model was produced by the OB op-eration on SD rats. The experimental animal were randomly divided into normal con-trol group, sham-operated control group, model control group, high dose of xiaoyao powder group, middle dose of xiaoyao powder group, low dose of xiaoyao powder group (30g/k^15g/kg^7.5g/kg) and amitriptyline positive control group(0.01g/kg). After14d recovery period, the experimental rats were supplied medicine (ig.) for4weeks. Weight, locomotor activity, consumption of a sweet solution and learning and memory ability by Morris water maze were observed. The content of monoamine neurotransmitters in hippocampus and cortex of the OB depression rats were detected by the ELISA method and the content of monoamine neurotransmitters in serum of the OB depression rats were detected by HPLC-ECD. The concentration of NO/NOS in the serum of the OB depression rats were detected by spectrophotometry. The ex-pressive levels of5-HT1AmRNA and5-HT2AmRNA in the hippocampus and cortex of the OB depression rats were detected by the method of RT-PCR. The expressive le-vels of5-HT1A receptor protein were detected by the method of western-blot. The changes of the cell structure in the CA3area of the hippocampus of the OB depres-sion rats and the effects of Xiaoyao powder to these changes were observed by the transmission electron microscope. The concentration of SOD and MDA in the liver and colon of the OB depression rats were detected. Results:1Comparing with the normal group, the weight of OB rats decreased obviously, and locomotor activities increased obviously, consumption of a sweet solution dropped and the learning and memory abilities dropped, the momoamine neurotransmitters content of the OB de-pression rats’ hippocampus, cortex and serum dropped, the expression of5-HT1AmRNA was increased, and the expression of5-HT2A mRNA dropped, the cells structure in CA3area of the hippocampus was abnormal. 2Comparing to the OB depression model group, the rats’weight of the groups of xiaoyao powder30g/kg,15g/kg,7.5g/kg cured after4w,the locomotor activities of the rats were cured,too. The consumption of a sweet solution of the rat of the groups of xiaoyao powder30g/kg,15g/kg were increased, after2w or3w the consumption of a sweet solution were improved, the learning and memory abilities the groups of xiaoyao powder30g/kg,15g/kg,7.5g/kg were improved. only the group of xiaoyao powder3Og/kg is obvious in the1st day training of space learning.3The momoamine neurotransmitter content of the OB depression rats’hippocampus, cortex and serum of the group of xiaoyao powder30g/kg,15g/kg,7.5g/kg after4w were cured, the group of xiaoyao powder30g/kg,15g/kg,7.5g/kg the expression of5-HT1AmRNA was increased, and the expression of5-HT2A mRNA dropped, just the5-HT1AmRNA in cortex of the7.5xiaoyao powder is obviously. The group of xiaoyao powder30g/kg,15g/kg,7.5g/kg the expression of5-HT1A protin in hippo-campus and cortex are increased,and xiaoyao powder30g/kg,15g/kg groups in hippo-campus and cortex were obvious. The group of xiaoyao powder30g/kg,15g/kg,7.5g/kg can improve the abnormal cells in CA3area of the hippocam-pus.4The group of xiaoyao powder30g/kg,15g/kg,7.5g/kg can improve the content of NO/NOS in the serum, and the group of30g/kg,15g/kg were obvious. The group of xiaoyao powder30g/kg,15g/kg,7.5g/kg can decreased the MDA content in the liver and colon of the OB depression rats, and increased the SOD content in the liver and colon of the OB depression rats.Conclusion:Xiaoyao-powder has good anti-depression effects to OB depression rats in changing the abnormal ethology and hippocampus neurons cellular structure, the anti-depression effects are related to regulating the level of momoamine neurotrans-mitters, increasing the NO level and antioxidant effects. Increasing5-HT level and the expression of5-HT1AmRNA and5-HT1A receptor protein, and regulating the balance of5-HT1A/5-HT2A were consider as one of the main anti-depression mechanism.