Diffrence And Singnificance Of Stat4 And Stat6 In Rats Model With Chroinc Bronchitis And Chronic Obstructive Pulmonary Disease

Objective:explore the difference and expression of signal transducers and activators of transcription 4(STAT4)and STAT6 in lung tissue from rats model with chronic bronchitis and chronic obstructive pulmonary disease (COPD).To analyze the relationship between the expression of this two cytokines, Immunity state and Thl/Th2 imbalance. In order to find a new way of therapeutics through study the pathogenesy of COPD in molecule level.Methods:40 wistar male rats (the age were about 5-6 weeks old, the weight were about 120-180g)were divided into 3 groups randomly:The control group(8 rats), the chronic bronchitis group(16 rats) and the COPD group(16 rats).using smoking way to build chronic bronchitis and COPD rats model. Two times a day at the beganning, about 30-50 minutes long and using 14 cigarettes each time. Adding two more cigarettes at the following days until up to 20 each time. It was about 7 weeks to build the chronic bronchitis rats model, about 14 weeks to COPD model. the control group were feeded 14 weeks normally. Taking out the middle right lung tissue after finished, and then stained with hematoxylin and eson (H-E).the pathologic changes were observed by optical microscope. At last,STAT4 and STAT6 protein were detected with immunohistochemistry. All dates were analysis by software SPSS13.0.Results:(1) The characteristic pathological manifestions of chronic bronchitis can be found in the lung tissue of the right rats model group. In COPD group we can find: the air spaces were enlarged, walls thinned and septal, the adjacent alveoli become confluent,creating large air space.In chronic bronchitis group:the degeneration of bronchoepithelial,hyperemia and edema of mucous,hypertrophy and hyperplasia of mucous glands and goblets cell,the wall of bronchitis become thickening, infiltrating by mononuclear cells and other inflammation cells. (2) STAT4 and STAT6 protein were chiefly expressed in epithelial cells. The STAT4 level of COPD group(0.81±0.11) were statistically higher than of the chronic bronchitis group (0.67±0.18, p=0.016,),and the level of chronic bronchitis group were statistically higher than of the control group(0.48±0.15 p=0.019). Different with STAT4, the STAT6 level of control group(0.84±0.44)were statistically higher than of the chronic bronchitis group (0.73±0.11 p=0.011), also higher than of the COPD group (0.63±0.79 p=0.000),and the level of chronic bronchitis group were higher compare with COPD group (p=0.042) statistically. There was a negative correlation between the content of STAT4 and STAT6 in all groups (r=-0.604,p=0.001)Conclusions:(1) It has shown enhances immunoreactivity for STAT4 in chronic bronchitis group and COPD group respectively. the STAT4 levels of Those two groups were much higher than of the control group. It shown that T helper lymphocytes-1(Th1) is predominant T- lymphocyte,Thl/Th2 system is imbalance,it also shown that STAT4 protein play an important role in advancement of COPD disease. (2) The STAT6 levels of chronic bronchitis group and COPD group is lower than of the control group, it shown that the differentiation of T helper lymphocytes-2 is depressed, which intensify the imbalance of Th1/Th2, STAT6 also has an important action in the advancement of COPD disease.(3) STAT4 and STAT6 are two key pointing cytokines that control differentiation of Th1 and Th2, it help to reveal the pathogenesis of COPD to study those two cytokines profoundly, it also can provide a new target for therapy Methods which through balance the abnormal state of immune system of COPD.