The Experimental Study On The Biological Rhythm Expression Of Substance P In Allergic Airway Inflammation Mice

OBJECTIVE:To establish the murine models of allergic airway inflammation and observe the pathological changes.To investigate the difference in expression of substance P in upper and lower airways during different time periods and the biological rhythm in it.METHODS:Eighty-four 6⁸-week-old male mice were randomly divided into 14groups,which were airway inflammation groups?0:00group,04:00group,08:00group,12:00group,16:00group,20:00group,24:00group?and normal control groups?0:00group,04:00group,08:00group,12:00group,16:00group,20:00group,24:00group?.The allergic airway inflammation models of mice were established by intraperitoneal injection of OVA+Al?OH?₃+PBS,5%OVA for nasal challenge and aerosol inhalation with 2.5%OVA.The normal control groups replaced OVA with equal amount of saline.After the model was completed,the symptoms were recorded and scored by the superposition method and more than 5 was judged as successful model.We collected blood from the right ventricle and got the supernatant after centrifugation.The SP levels were measured by ELISA.The expression of SP in nasal mucosa,left lung tissue and left bronchial tissue during different time periods was obversed with RT-PCR and immunohistochemical technique.RESULTS:In allergic airway inflammation groups,the plasma SP levels were higher than normal control groups?P<0.05?,and 0:00 group?321.99±26.41?pg/ml,04:00group?310.76±23.1?pg/ml and 24:00group?335.62±25.82?pg/ml were higher than other experimental groups?P<0.05?.The expression of SPmRNA in nasal mucosa,left lung tissue and left bronchial tissue was higher than control groups?P<0.05?.By observing immunohistochemical sections,the expression of SP in allergic airway inflammation groups was higer than control groups.Conclusions:Substance P participates in the pathogenesis of allergic airway inflammation and shows biological rhythmic expression,the peaks are during04:00-08:00 in the morning,which indicates that neuropeptide palys an important role in the occurrence and development of allergic airway inflammation and helps us learn the biological rhythm deeply.It initially reveals the role and significance of neuropeptides in the biological rhythm and may provide new reference for treating allergic airway inflammation.