Effect Of Xiaoyao Powder On Chronic Unpredictable Mild Stress-induced Gan-Stanancy Syndrome In Rats

BackgroundWith the accelerating pace of modern life, work stress, social competition and other reasons have make people’s mental pressure increasing. In modern clinical disease, liver depression syndrome is a common phenomenon. Along with the establishment of the bio-psycho-social medical model, liver depression syndrome plays an important role in various diseases.The study about liver depression syndrome has draw much attention.Years of research and exploration results show that the liver depression syndrome correlates with stress closely, it involves the body’s nervous, endocrine, circulatory, digestive, immune system. The research of stress from foreign involed the hypothalamic-pituitary-adrenal cortex system (HPA) and the locus coeruleus-sympathetic-adrenal medullary system (LC-NE),that is so more comprehensive than our country. In China, although the research in the neuroendocrine system is the hot spots of liver depression syndrome in recent years, but mostly concentrated on the HPA axis, the hypothalamic-pituitary-thyroid axis (HPTA) or hypothalamus pituitary-gonadal axis (HPGA), about the LC-NE has not been reported. Therefore, our research group will take the LC-NE axis and the HPA axis, the hypothalamic pituitary-thyroid axis (HPTA) or the hypothalamic-pituitary-gonadal axis (HPGA) as the point, hoping to more fully reveal liver depression syndrome nature.From the published literature, depression and liver depression Syndrome are corresponded directly by most physicians. Depression is a kind of emotional disorders, manifested as a long-lasting depression, with physical discomfort and sleep disorders.. Belongs to Chinese medicine,"depressive" category.Pathogenesis of depression is very complex, it has not yet been fully elucidated, it is generally agreed that is the result of the interaction of biological, psychological, social (cultural) factors. About hypothesis of depression, the incidence of neural and biochemical mechanisms are more. Catecholamines is one of the more generally accepted hypothesis. Catecholamines is an important hub of endogenous neurotransmitter, TH is the rate-limiting enzyme of catecholamine biosynthesis.Locus coeruleus-norepinephrine system is related to emotions, behavior, state-dependent cognitive processes and states of consciousness,it participate in awareness and attention. Chronic stress and locus coeruleus function are closely related to depression.ObjectivesInvestigate the regulation of xiaoyao powder on behavioral and tyrosine hydroxylase changes of chronic unpredictable stress-induced rat model of liver depression syndrome.Methods1. To replicate the effective rat model of liver depression syndrome using chronic constraint stress.360rats were randomly divided into four groups:control group, depression model group, Xiaoyao Powder group and fuxiting group.2. Drug InterventionRats from group C were given Xiaoyao Powder in the same ways.Dose level for Xiaoyao Powder in the rats was set according to the day dose for a normal adult;It was10g/kg body weight everyday, group D were given Fluoxetine5mg/kg per day; while the other two groups were given2ml physiological saline per day at16:00.3.We may evaluate the model by the observation of behavior, fluid consumption test and the curative effects. 4. HE staining and Nissl staining method to observe the morphological changes in LC about14days groups.5. Observe the Expression of TH in LC by immunohistochemical method.6. Observe the Expression of TH in LC by Western blotting.7. Observe the Expression of TH in LC by Real-time fluorescence quantitative (real-time PCR).8. The obtained data were statistically analyzed with SPSS16.0software.Results1. behavior,weight and sucrose consumption resultsIn7days groups,14days groups and21days groups, the weight,sucrose consumption, crossing and standing times of the rats in model group decreased significantly (compared with control group, P<0.05); Continually administrated the weight,sucrose consumption, crossing and standing times in the model group treated with Xiaoyao Powder and fluoxetine increased significantly, but1day group and3days groups were not significant。2. nissl staining resultsSwelling, shrinkage of nerve cells of the rat in locus coeruleus after chronic stress, the Xiaoyao powder and fluoxetine can improve the performance, this effect of Xiaoyao powder is more pronounced.3. test results of immunohistochemical stainingIt shows cell number was less than group A (P<0.05). By Xiaoyaosan and fluoxetine intervention, the expression of TH in C group and D group has upward trend.4. western blot analysisThe expression of TH protein in normal group is lower liver depression group, Xiaoyao powder group and fluoxetine group are greater than the liver depression group,It was statistically significant (P<0.05).5. test of PCRTH gene expression is lowder than the normal group.Xiaoyao powder and the Fluoxetine make THmRNA up-regulated, it shows significant (P<0.05).Conclusion1. we copied depression rat model learning from home and abroad,a variety of different conditions were randomly combined with.That shows chronic unpredictable stress can induced depression-like behavior.2. Xiaoyao Powder had an antagonized effect on liver depression, it embodied in the increase in sugar intake, improved the horizontal and vertical movements.3. The expression of TH weakens after chronic stress, Xiaoyaosan and fluoxetine can enhance the function of central TH by increasing the expression of tyrosine hydroxylase in the locus coeruleus. This may be one of the antidepressant mechanism.