The Effects Of Qinbai Qingfei Concentrated Pellets On NEP And SP Changs In Lung Tissue Of Infected Cough Rats

Purpose:On the basis of the experimental research,the amount of neutral endopeptidase(NEP)and substance P in the lung tissue of PIC rats will be measured.And the significance of NEP and SP changes of neuorenic inflammation in post-infectious cough airway.Meanwhile,the regulatory effects of Qinbai Qingfei Concentrated Pellets towards NEP and SP will be observed.Methods:1.Establish the PIC animal model by using cigarette-smoking and small dose of endotoxin to simulating gram negative bacterial infection and capsaicin aerosolized inhalation.2.The SD rats were randomly divided into 6 groups:blank control group,model group,high-dose group,middle-dose group,low-dose group,and montelukast positive control group,to observe the frequency of cough,pathological changes of lung tissue,and the amount of NEP and SP in lung tissue(ELISA Methods).Results:1.Cough frequency:The cough frequency of model group was significantly increased compared with the blank control group,the difference was statistically significant(P<0.01).C-ompared with the model group,the cough frequency of Qinbai high-dose group,Qinbai middle-dose group and positive control group was significantly reduced,the difference was statistically significant(P<0.05).There was no significant difference between the high-dose group,the middle-dose group and the positive control group(P>0.05).There was no significant difference in the number of cough between the low-dose group and the model group(P>0.05).2.Pulmonary pathology:Pathological changes around and around the center of lobectomy are more obvious than the edges in tracheobronchial diseases and the lesion of alveoli of model group.And there was no significant difference in bronchial lesions in each group while alveolar epithelial cells showed necrosis and degeneration.The alveolar wall was not enlarged and edematous,and the congestion and vasculitis of the blood vessels were improved.3.Immunohistochemical staining results: From the NEP aspect,deep yellow positive reactant were observed in lung tissue of rats of Qinbai high-dose and middle-dose groups,while lighter color reactant were observed in model group,low-dose group and positive control group.For SP,compared with the blank group,deep yellow positive reactant were observed in lung tissue of rats of model group and Qinbai low-dose group,while lighter color were observed in Qinbai high-dose group,Qinbai middle-dose group and positive control group.4.Results of semiquantitative immunohistochenmistry assay: For SP expression:The model group was significantly enhanced compared with the blank group,the difference is significant(P<0.01);Compared with the model group,the high-dose group,the middle-dose group and the positive control group were significantly weakened,the difference is significant(P<0.05);There was no significant difference between the low-dose group and the model group(P>0.05);The expression of SP in the high-dose group was significantly lower than the middle-dose group and the positive control group(P<0.05);There was no significant difference between the positive control group and the model-dose group(P>0.05).For NEP expression,the model group was significantly reduced compared with the blank group,the difference is significant(P<0.01);Compared with the model group,the expression of NEP in the middle and high dose group was significantly higher,the difference is significant(P<0.05);There was no significant difference between the low dose group and the positive control group(P>0.05);The expression of NEP was stronger in the high-dose group than that in the middle dose group(P<0.05).Conclusion:1.Qinbai Qingfei Concentrated Pellets improved the pulmonary pathological changes of post-infectious ough rats.2.Qinbai Qingfei Concentrated Pellets decrease the amount of SP and increase the amount of NEP in lung tissue of post-infectious cough rats which indicates that the therapeutic effect can be achieved by increasing the content of NEP and decreasing the content of SP.