| Objective:To establish the experimental animal model with benign hyperplasia of granulation tissue airway stenosis,induce granulation tissue hyperplasia through mechanical injury of New Zealand rabbit airway mucosa to formate airway stenosis.Method:(1)A total of 24 New Zealand rabbits of which weight in the range of 2.7-3.2kg, randomly divided into the model group and the sham operation group.There are 4 rabbits in each group;(2)For the model group,the anterior wall of the trachea were evenly brushed 30 times by the use of hard nylon brush.For the sham operation group, only cross cutting the tracheal, no scraping.(3)Materials were drawn from all groups respectively at 7,10,13 days after tracheotomy to gross observe the changes of specimens;(4)HE staining was applied to the specimens,pathologic histological changes were observed by optical microscope.Results:(1)Macroscopic observation:1)The part of trachea cross-section in the sham operation group present as pale white. No stenosis or granulation tissue were observed in this group;2)The part of trachea cross-section in the model group had prominent hyperemia and presented as dark red. Stenosis and granulation tissue were observed in this group.The degree of stenosis increased with the time of modeling;(2)HE staining showed that:1) The tracheal mucosal was intact in sham operation group,and it had different degrees of detachment and loss in all of model groups;2) The thickness from the tracheal cartilage junction plane to the submucosal increases with the molding time in the model groups, and all of them were significantly longer than the sham operation group.Conclusion:The modeling method by wiping with the hard nylon brush has the advantages such as convenience, good repeatability, high success rate, easy popularization and so on, can provide a mature and stable experimental animal model for exploring the formation mechanism of the benign hyperplasia of granulation tissue airway stenosis and the method of treatment.Objective:Using treatment on airway granulation tissue hyperplasia by cryoablation, to observe the effect of different time of cryoablation on the proliferation of airway granuloma,and explore the best cryoablation time so as to provide experimental data for the standardization of treatment of patients with benign granulation tissue hyperplasia of airway stenosis.Method:(1)The experimental model of granulation tissue proliferation of tracheal stenosis after modeling 10d was selected,they were randomly divided into treatment group, model control group (only scraping, not cryoablation),another sham operation group (only tracheal transection, without scraping or cryoablation), According to the time of cryoablation it was divided in following 3 groups:30sec group, lmin group and 2min group.8 rabbits in each group;(2)On the 10th day after modeling, according to the different groups,carry out the corresponding time of cryoablation, the model control group and sham operation group were again performed tracheal transection and suture;(3)Materials were drawn at the 7th day for cryoablation, HE staining and measure the vertical distance which from the tracheal cartilage junction plane to the submucosal;(4)The expression of CD34 protein and CD34 mRNA in tracheal tissue of each groups were determined by immunohistochemical staining and RT-qPCR analysis.then the statistical analysis was carried out.Result:(1)Macroscopic observation:1)The trachea cross section of the sham operation group was smooth, which was close to the normal trachea tissue, which was pale white, without the growth of granulation tissue;2) Different degrees of granulation tissue hyperplasia and lumen stenosis were seen at the cross section of the trachea in the model control group and the treatment group.(2) Histopathological observation:1)The mucous membrane of the anterior midline of trachea was obviously thinner than that of both sides;2)The trachea epithelium of the sham operation group was intact; the model control group and the treatment group were all showed that the epithelium of the trachea was lost, loss and local squamous metaplasia;3)The tracheal cartilage in the model group and the 1 minute group was thicker than the sham operation group, the 30 second group and the 2 minute group;4)On the 17th day after modeling, model control group and treatment group were found in fibroblasts, inflammatory cells decreased,capillary occlusion and decrease,collagen fibers increased and become coarse and so on.(3)The measurement results of the submucosal layer under the optical microscope:1)The submucosal layer of the sham operation group was thinner than that of the other groups, and the difference was significant (P<0.05);2)The submucosal layer of the 30 second group was thinner than that of the other treatment group (1 minutes group,2 minutes group) and model control group, and the differences was statistically significant (P<0.05);3)There was no significant difference in the submucosal layer of 1 minutes group and that of model control group (P>0.05);4)The submucosal layer of 2 minutes group was thinner than that of model control group, and the difference was statistically significant (P<0.05).(4)Measurement results of the average optical density of CD34 protein expression:1)The average light density of CD34 protein expression in sham operation group was lower than that in other groups, and the difference was statistically significant (P<0.05);2)The average light density of CD34 protein expression in 30 second group was significantly lower than that in other treatment groups (1 minutes group,2 minutes group) and model control group, and the difference was statistically significant (P<0.05);3)The average light density of CD34 protein expression in 1 minutes and 2 minutes group was higher than that in model control group, and the difference was statistically significant (P<0.05).(5)Measurement results of the relative expression of CD34 gene:1) The relative expression of CD34 gene in the sham operation group was lower than model control group, and the difference was statistically significant(P<0.05);2)The relative expression of CD34 gene in 30 second group was significantly lower than that in other treatment groups (1 minutes group,2 minutes group) and model control group,and the difference was statistically significant (P<0.05);3)The relative expression of CD34 gene in 1 minutes group was higher than that in model control group, and the difference was statistically significant (P<0.05);4)The relative expression of CD34 gene in 2 minutes group was significantly lower than the model control group,and the difference was statistically significant (P<0.05).Conclusions:1)30sec and 2min of the cryoablation showed inhibition to the formation of granulation tissue; 1min of the cryoablation has no significant inhibition of granulation tissue formation and studying the mechanism of it should be done in future;2)In all treatment groups,30sec has the most obvious inhibition to granulation tissue, which may be the best time to cryoablation;3)The expression amount of CD34 can be used as a index to reflect the degree of granulation tissue proliferation. |
PDF Full Text Request