Experimental Research On Expression Of Anion Exchanger 2 In Airway Epithelial Cells Of Guinea Pig Model Of Allergic Asthma.

[Objective]: To study expression and its implication of AE2 protein and mRNA in epithelium of asthmatic guinea pigs. [Method]: To use 20 guinea pigs and divide them into two groups at random without distinction of sex. One group names Control group( n=10) and the other Asthma one(n=10). The antigen-sensitized and -challenged guinea pig model of allergic asthma is made after consecutive 3d challenge. To detect pre-and post-challenge respiratory freqency until 3d postchallenge; To observe eosinophil(EOS) infiltration around bronchial mucous membrane and pulmonary tissue in asthmatic model; The number of eosinophils in bronchoalveolar lavage fluid is also observed; To detect the concentratin of serum IgE and count eosinophil of blood. Using the epithelium in airway of guinea pig, to examine the levels of AE2 protein and mRNA by means of western blotting and RT-PCR technique. [Results]: ①the detection of respiratory frequency: The ovalbumin (OVA)-sensitized guinea pigs and the Control group both have a steady breath on the 14th day in experiment , there are obvious differences after exciting. The Control group(105.4±7.63bpm ) do not relatively have a significant difference (p> 0.05 ) with the Asthma group (108.8±6.92bpm) before exciting; The Control group (106.8±5.67bpm ) relatively has a significant difference (p<0.01 ) with the Asthma group (130.5 ±7.86bpm ) after challenge; Not having significant difference (p> 0.05 ) to compare in the same Control group, the Asthma group relatively has a significant difference (p<0.01 ).②the detection of serum IgE and count eosinophil of blood: Compared with the concentration of IgE of the Control group (72.7±27.79 ) that (390.6±154.16 ) of the Asthma group has significant difference (p<0.01); There is significant difference (p <0.01) between the Control group( 0.051±0.017)and the Asthma group (0.265±0.024 )in EOS count.③pulmonary tissue pathologically morphological change: We find, under the optics microscope,that the Control group, guinea pig lung tissue slices bronchus membranes'epithelial cells arrange neatly. There are no epithelial cells to come off and no inflammation cells out of the ducts, a little lymphocytes are seen in ducts ,not finding eosinophil infiltration .But the asthma group has a distinct picture: the epithelial cells of bronchus membranes arrange disorderlily . Some epithelium come off into the airway ducts .In alveolus interval we can see more lymphocytes and eosinphilic granulocytes soakage .The basolateral membranes become thicker. Bronchus duct is hard to get at all even to dwindle, the mucus blocks the airway ducts partly ④the levels of AE2 protein and mRNA:western blotting reveals that AE2 protein has a basic expression in the Control group. AE2 protein expression of the Asthma group(168287.0 ±28663.68) decreases obviously compared with the Control group(244350.4±29358.02)(P<0.01). This is true of AE2 mRNA expression. Compared with the Control group(0.852±0.0107), the level of AE2 mRNA of the Asthma group decreases obviously(0.790±0.0104)(P<0.01). [Conclusions]: 1,Guinea pig's allergic bronchus asthma models appear obvious dyspnea, wheeze; EOS and serum IgE obviously rise in the blood and BALF;Obvious pathologically morphological change appears. 2,AE2 protein and mRNA have their basic expression in normal guinea pig.In guinea pig asthma models,expressions of their epithelium AE2 protein and mRNA downregulate.