Establishment Of Psychological Stress Asthmatic Rat Model And The Mechanism Of The Method Of Modulating Liver And Lung

Objective Asthma is a typical psychosomatic disease,and emotional factors play a key role in its pathogenesis.Studies have shown that changes in mood may cause neurohornnonal-endocrine-immune imbalance,and HPA axis is one of the main regulatory pathways.Under the condition of psychological stress,the airway inflammation obviously enhanced,and the sensitivity to glucocorticoid decreased.The mechanism may be related to the decrease of expression and function of GR.In this study,we established the model of psychological stress asthmatic rats with the characteristics of clinical intelligence and pathogenesis.The related indexes were used to detect the effect of emotion on the function of HPA in asthmatic rats and the relationship with the airway inflammation.The changes of macrophages,behavior and serum,lavage fluid and lung tissue were observed in model rats treating with Xiaochuanning granule to explore the regulation of the method of modulating liver and lung on HPA axis and airway inflammation of psychological stress asthmatic rat,to clarify the mechanism of the method of modulating liver and lung.Method In the animal experiment,SD rat were randomly divided into control group,stress group,asthmatic group,stress asthmatic group,western medicine group and Traditional Chinese Medicine group.The model of psychological stress asthmatic rat was established by sensitization and challenge with ovalbumin(OVA)and immobilization in restrained box.The model was evaluated from macroscopic characterization,behavioral and pulmonary function.The function of HPA axis in the models and its relationship with airway inflammation were deeply studied.TCM group were treated with XiaoChuanNing granules,which were compared with those of other groups.The concentration of related-index,the expression of positive cells and the protein in the lung tissue,serum and bronchoalveolar lavage fluid were researched to observe the regulation of the method of modulating liver and lung on HPA axis and immune inflammation imbalance.Result 1)The results of animal experiments showed that the psychological stress asthmatic rat model,induced by OVA mixture with restraint,was proved to besuccessful.And stress asthmatic rat showed low mood,loss of interest,dull hair,loose stools,reducing food intake,slowly weight gain,and sceatched noses and abdominal skin,coughed,sneezed and wheezed in the throat when stimulated.Compared with control group,the points of vertical movement decreased significantly(P<0.05,P<0.01).Preference for sucrose,the times of active moves in tail suspension test(TST)of stress asthmatic rat obviously decreased(P<0.01),and the duration of immobility increased significantly(P<0.01).Pulmonary function indicators,including peak expirory flow(PEF),PEF25-75%,forced expiratory volume in 0.3s[FEV(0.3)]/forced expiration volume capacity(FVC)significantly declined(P<0.05,P<0.01,P<0.01),while mean inspiratory airway resistance(Ri),and mean expiratory airway resistance(Re)increased remarkably(P<0.05,P<0.01).Peripheral blood eosinophil cells increased(P<0.01),and infiltration of inflammatory cell in lung tissue was obvious.Compared with the stress group or asthmatic group,the signs and indicators of stress asthmatic group were all much worse.2)Compared with the normal group,the levels of CRH,ACTH and CORT in serum and BALF were significantly higher than those in the normal group(P<0.01),and the levels of IgE,IL-4 and IL-17 were significantly increased(P<0.01).IFN-? content decreased significantly(P<0.01).The expression and content of IL-4 and IL-17 positive cells were significantly increased(P<0.01),and the expression of IFN-y positive cells was significantly decreased(P<0.01),While the content of IFN-? in lung tissue was not significantly decreased,the difference was not statistically significant(P>0.05).Compared with the stress group or the asthma group,the HPA axis and the airway inflammation indexes of the stress asthma group were deteriorated.Relevant studies showed that the content of CORT in serum and broncho alveolar lavage fluid was negatively correlated with IFN-?,but positively correlated to IgE,IL-4 and IL-17;and the level of GR in bronchial lung tissue was opposite,which was negatively correlated to the content of IFN-? and IL-4 and IL-17.The CORT content were negatively correlated to the proportion of sugar and sugar consumption,and GR content was positively correlated to sugar consumption,the proportion of sugar,turning times and vertical movement,but negatively with the static time.3)After the treatment with XiaoChuanNing granules,the rat showed a decline in activity,slow response,hair dull in early time,But late time,it showed more active,increased food intake,increased interest in the surroundings.In the process of stimulation,the rat performed breathing faster,deepening abdominal contraction,scratching the head and the belly hair.Compared with the model group,the points of vertical movement increased significantly in TCM group(P<0.01).Preference for sucrose,the times of active moves in tail suspension test(TST)obviously increased(P<0.01),and the duration of immobility decreased significantly(P<0.01).Pulmonary function indicators,including PEF,FEF25-75%,FEV0.3/FVC slightly increased,while the Ri and Re decreased,remarkably(P<0.01).Peripheral blood eosinophil cells were significantly reduced(P<0.01);infiltration of inflammatory cell in lung tissue was significantly reduced.The levels of CRH,ACTH and CORT in the serum and bronchoalveolar lavage fluid in the TCM group were significantly lower than those in the asthmatic group(P<0.01),while the GR was significantly higher than that in the asthmatic group(P<0.01).The levels of IL-4 and IL-17 in serum,bronchoalveolar lavage fluid and bronchial lung tissue were significantly decreased(P<0.01),and the expression of IFN-y positive cells in lung tissue was significantly decreased(P<0.01);but the content was not significantly decreased(P>0.05).The results of correlation study showed that the CORT content was negatively correlated with IFN-? and positively correlated with IgE,IL-4 and IL-17.The content of GR in lung tissue was positively correlated with IFN-y level;but IL-17 and other inflammatory indicators were negatively correlated.The CORT content was negatively correlated with sugar consumption,sugar water ratio,the turning times and the number of vertical movement,but positively correlated to the static time(P>0.05).Conclusion 1)The psychological stress asthmatic rat model,induced by OVA mixture with restraint,was proved to besuccessful.It is in accordance with clinical characteristics of bronchial asthma with liver qi stagnation pattern.2)Emotional factors may cause the function of HPA axis hyperactivity,expression of GR downregulation in lung tissue,resulting in increased airway inflammation.3)Through experimental results,it was suggested that the method of regulating liver and lung can significantly relieve the anxiety and depression of psychological stress asthmatic rat,and reduce the level of related-index of HPA axis in serum and lavage,enhance GR expression in lung tissue,reduce airway inflammation.It prompts that the methods of regulating liver and lung may achieve the regulation of psychological stress asthma by regulating the HPA axis.